做最强的自己，与子征战兮路漫长

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Stockholm个大头！我又不是被绑架了～～

！！！UID: 2349378

绑架的时间长了就会爱上绑匪

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饿地神那，宰了饿吧

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１５０词一个单元，推荐按照杨鹏方法记忆。

https://bbs.gter.net/thread-758679-1-1.html

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Polychlorinated Biphenyls (PCBs)

http://www.wanfangdata.com.cn/qikan/periodical.Articles/zhldwszyb/zhld2005/0504/050432.htm

Health effectsThe toxicityof PCBs to animals was first noticed in the 1970s when emaciatedseabird corpses with very high PCB body burdens were washed up onbeaches. The source(s) of the PCBs was (were) unknown though, becauseseabirds may die at sea and be washed ashore from a very wide area.Where they were found was no reliable indicator of where they had died.
The toxicity of PCBs varies considerably among congeners. Thecoplanar PCBs, known as non-ortho PCBs because they are not substitutedat the ring positions ortho to (next to) the other ring, (i.e. PCBs 77, 126, 169, etc), tend to have dioxin-likeproperties, and generally are among the most toxic congeners. BecausePCBs are almost invariably found in complex mixtures, the concept oftoxic equivalency factors (TEFs) has been developed to facilitate riskassessment and regulatory control, where more toxic PCB congeners areassigned higher TEF values. One of the most toxic compounds known, 2,3,7,8-tetrachlorodibenzo[p]dioxin, is assigned a TEF of 1. [3]
[edit] Symptoms

• Humans

The most commonly observed health effects in people exposed to large amounts of PCBs are skin conditions such as chloracne and rashes,but these were known to be symptoms of systemic poisoning dating backto the 1920s. Studies in exposed workers have shown changes in blood and urine that may indicate liverdamage. PCB exposures in the general population are not likely toresult in skin and liver effects. Most of the studies of health effectsof PCBs in the general population examined children of mothers who wereexposed to PCBs.

• Animals

Animals that ate food containing large amounts of PCBs for shortperiods of time had mild liver damage and some died. Animals that atesmaller amounts of PCBs in food over several weeks or months developedvarious kinds of health effects, including anemia; acne-like skin conditions (chloracne); and liver, stomach, and thyroid gland injuries (including hepatocarcinoma). Other effects of PCBs in animals include changes in the immune system,behavioral alterations, and impaired reproduction. PCBs are not knownto cause birth defects in humans, although those that have dioxin-like activity are known to cause a variety of teratogenic effects in animals.

• Effects during pregnancy/breastfeeding

Women who were exposed to relatively high levels of PCBs in theworkplace or ate large amounts of fish contaminated with PCBs hadbabies that weighed slightly less than babies from women who did nothave these exposures. Babies born to women who ate PCB-contaminatedfish also showed abnormal responses in tests of infant behavior. Someof these behaviors, such as problems with motor skills and a decreasein short-term memory, lasted for several years. Other studies suggestthat the immune system was affected in children born to and nursed bymothers exposed to increased levels of PCBs. The most likely wayinfants will be exposed to PCBs is from breast milk.Transplacental transfers of PCBs were also reported. Because an infantwill receive more than ten times the amount of PCBs from breast milkthan it will for the rest of its life [citation needed], it is being debated whether the benefits of breast-feeding are greater than the risks from exposure to PCBs.Studies have shown that PCBs alter estrogen levels in the body andcontribute to reproduction problems. In the womb, males can befeminized or the baby may be intersex, neither a male nor a female.Also, both sets of reproductive organs may develop. More instances ofthis are being reported. Biological magnification of PCBs has also ledto polar bears and whales that have both male and female sex organs andmales that cannot reproduce. This effect is also known as endocrine disruption. Endocrine Disrupting Chemicals (EDC's) pose a serious threat to reproduction in top-level predators.[edit] Cancer linkA few studies of workers indicate that PCBs were associated with specific kinds of cancer in humans, such as cancer of the liver and biliary tract. Rats that ate food containing high levels of PCBs for two years developed liver cancer. The Department of Health and Human Services (DHHS) has concluded that PCBs may reasonably be anticipated to be carcinogens. The US Environmental Protection Agency (EPA) and the International Agency for Research on Cancer(IARC) have determined that PCBs are probably carcinogenic to humans.PCBs are also classified as probable human carcinogens by the National Cancer Institute, World Health Organization, and the Agency for Toxic Substances and Disease Registry. Recent research by the National Toxicology Program has confirmed that PCB126 (Technical Report 520) and a binary mixture of PCB126 and PCB153 (Technicial Report 531) are carcinogens.
[edit] Mechanism of actionAs discussed, PCBs exhibit a wide range of toxic effects. Theseeffects may vary depending on the specific PCB. Toxicity of coplanarPCBs (such as dioxin) and mono-ortho-PCBs are thought to be primarilymediated via binding to aryl hydrocarbon receptor (AhR).[4][5] Because AhR is a transcription factor, abnormal activation may disrupt cell function by altering the transcription of genes. The concept of toxic equivalency factors (TEF) is based on the ability of a PCB to activate AhR.
However, not all effects may be mediated by the AhR receptor. Forexample, di-ortho-substituted non-coplanar PCBs interfere withintracellular signal transduction dependent on calcium; this may lead to neurotoxicity.[6] Ortho-PCBs may disrupt thyroid hormone transport by binding to transthyretin.[7]

[ 本帖最后由 zhangheng1020 于 2007-11-6 02:26 编辑 ]

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Health effects

The toxicity of PCBs to animals was first noticed in the 1970s when emaciated seabird corpses with very high PCB body burdens were washed up on beaches. The source(s) of the PCBs was (were) unknown though, because seabirds may die at sea and be washed ashore from a very wide area. Where they were found was no reliable indicator of where they had died.

The toxicity of PCBs varies considerably among congeners. The coplanar PCBs, known as non-ortho PCBs because they are not substituted at the ring positions ortho to (next to) the other ring, (i.e. PCBs 77, 126, 169, etc), tend to have dioxin-like properties, and generally are among the most toxic congeners. Because PCBs are almost invariably found in complex mixtures, the concept of toxic equivalency factors (TEFs) has been developed to facilitate risk assessment and regulatory control, where more toxic PCB congeners are assigned higher TEF values. One of the most toxic compounds known, 2,3,7,8-tetrachlorodibenzo[p]dioxin, is assigned a TEF of 1. [3]

[edit] Symptoms

    * Humans

    The most commonly observed health effects in people exposed to large amounts of PCBs are skin conditions such as chloracne and rashes, but these were known to be symptoms of systemic poisoning dating back to the 1920s. Studies in exposed workers have shown changes in blood and urine that may indicate liver damage. PCB exposures in the general population are not likely to result in skin and liver effects. Most of the studies of health effects of PCBs in the general population examined children of mothers who were exposed to PCBs.

    * Animals

    Animals that ate food containing large amounts of PCBs for short periods of time had mild liver damage and some died. Animals that ate smaller amounts of PCBs in food over several weeks or months developed various kinds of health effects, including anemia; acne-like skin conditions (chloracne); and liver, stomach, and thyroid gland injuries (including hepatocarcinoma). Other effects of PCBs in animals include changes in the immune system, behavioral alterations, and impaired reproduction. PCBs are not known to cause birth defects in humans, although those that have dioxin-like activity are known to cause a variety of teratogenic effects in animals.

    * Effects during pregnancy/breastfeeding

    Women who were exposed to relatively high levels of PCBs in the workplace or ate large amounts of fish contaminated with PCBs had babies that weighed slightly less than babies from women who did not have these exposures. Babies born to women who ate PCB-contaminated fish also showed abnormal responses in tests of infant behavior. Some of these behaviors, such as problems with motor skills and a decrease in short-term memory, lasted for several years. Other studies suggest that the immune system was affected in children born to and nursed by mothers exposed to increased levels of PCBs. The most likely way infants will be exposed to PCBs is from breast milk. Transplacental transfers of PCBs were also reported. Because an infant will receive more than ten times the amount of PCBs from breast milk than it will for the rest of its life [citation needed], it is being debated whether the benefits of breast-feeding are greater than the risks from exposure to PCBs.

    Studies have shown that PCBs alter estrogen levels in the body and contribute to reproduction problems. In the womb, males can be feminized or the baby may be intersex, neither a male nor a female. Also, both sets of reproductive organs may develop. More instances of this are being reported. Biological magnification of PCBs has also led to polar bears and whales that have both male and female sex organs and males that cannot reproduce. This effect is also known as endocrine disruption. Endocrine Disrupting Chemicals (EDC's) pose a serious threat to reproduction in top-level predators.

[edit] Cancer link

A few studies of workers indicate that PCBs were associated with specific kinds of cancer in humans, such as cancer of the liver and biliary tract. Rats that ate food containing high levels of PCBs for two years developed liver cancer. The Department of Health and Human Services (DHHS) has concluded that PCBs may reasonably be anticipated to be carcinogens. The US Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC) have determined that PCBs are probably carcinogenic to humans. PCBs are also classified as probable human carcinogens by the National Cancer Institute, World Health Organization, and the Agency for Toxic Substances and Disease Registry. Recent research by the National Toxicology Program has confirmed that PCB126 (Technical Report 520) and a binary mixture of PCB126 and PCB153 (Technicial Report 531) are carcinogens.

[edit] Mechanism of action

As discussed, PCBs exhibit a wide range of toxic effects. These effects may vary depending on the specific PCB. Toxicity of coplanar PCBs (such as dioxin) and mono-ortho-PCBs are thought to be primarily mediated via binding to aryl hydrocarbon receptor (AhR).[4][5] Because AhR is a transcription factor, abnormal activation may disrupt cell function by altering the transcription of genes. The concept of toxic equivalency factors (TEF) is based on the ability of a PCB to activate AhR.

However, not all effects may be mediated by the AhR receptor. For example, di-ortho-substituted non-coplanar PCBs interfere with intracellular signal transduction dependent on calcium; this may lead to neurotoxicity.[6] Ortho-PCBs may disrupt thyroid hormone transport by binding to transthyretin.[7]

http://library.med.utah.edu/WebPath/ATHHTML/ATH018.html

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http://path.upmc.edu/cases/index.html

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This large abdominal atherosclerotic aortic aneurysm below the renal arteries at the right and above the bifurcation at the left has been opened to reveal abundant layered mural thrombus within the aneurysm [Image contributed by Dr. John Nicholls, Hong Kong University].
http://library.med.utah.edu/WebPath/ATHHTML/ATH043.html

A mural thrombus is a thrombusattached to a large vessel wall. It is usually referring to the heartor aorta. The common causes of mural thrombi are myocardial infarction,myocarditis, aneurysms. 1

[ 本帖最后由 zhangheng1020 于 2007-11-6 15:26 编辑 ]

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These are "lines of Zahn" which are the alternating pale pink bands of platelets with fibrin and red bands of RBC's forming a true thrombus.
http://library.med.utah.edu/WebPath/ATHHTML/ATH031.html
Lines of Zahn are a characteristic of thrombi that appear when formed in the heart or aorta.They have visible and microscopic laminations produced by alternatingpale layers of platelets mixed with fibrin and darker layer containing red blood cells.Their significance implies thrombosis at a site of rapid blood flow. Inveins or smaller arteries, where flow is not as constant, they are lessapparent. They are named after German pathologist Friedrich Wilhelm Zahn (1845-1904).

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DisorderMechanismAntiphospholipid syndromeThereare circulating antibodies that bind plasma proteins with an affinityfor phospholipid surfaces, and this can cause thrombosis and in womenstillbirth. This syndrome is most often acquired in adulthood, eitherfrom an underlying disease or as an idiopathic condition. The twosubsets of this syndrome, as defined by laboratory testing, are: lupusanticoagulant (which may or may not be seen with SLE), andanti-cardiolipin antibodyFactor V Leiden mutationThisis the most common inherited form of hypercoagulability. The mutation,which leads to activated protein C resistance, is present in 5% ofCaucasians but is rare in persons of African and Asian ancestry.Heterozygotes have a mild risk for thrombosis, but the rare homozygoteshave a marked risk. A point mutation leads to impaired inactivation offactor V by activated protein C. Recurrent venous thrombosis can occur,starting even in young persons, and in women stillbirth.Elevated factor VIIIThiscondition is as common as factor V Leiden mutation. There may begenetic and environmental factors causing it. Oral contraceptive useincreases factor VIII levels. The result is deep venous thrombosis.Malignant neoplasmsNeoplasticcells may elaborate a factor, such as a thromboplastin-like substance,that can increase the risk for thrombosis. This is one form ofparaneoplastic syndrome, with the name Trousseau's syndrome. There canbe venous (more likely) or arterial thrombosis.Protein C, Protein S, antithrombin III deficienciesTheseconditions are autosomal dominant and lead to recurrent venousthrombosis, even starting in young persons. Thrombosis is oftenspontaneous, without other precipitating events. They can be detectedby laboratory testing for the respective coagulation factorSticky platelet syndromeThisis an autosomal dominant disorder that can lead to both arterial andvenous thrombosis. Stillbirth may occur in women. Stress is aprecipitating event.HomocystinemiaPersonswith elevated plasma homocysteine levels not only have increasedproblems with atherosclerosis, but also arterial and venous thrombosis.Stillbirth may occur in women.Prothrombin mutationTheprothrombin G20210A mutation increases the level and activity ofprothrombin that mildly increases the risk for arterial and venousthrombosis. The mutation occurs more often in persons of southernEuropean ancestry.Plasminogen abnormalitiesPlasminogen,which has an anticoagulant effect, can be deficient. The featuresresemble protein C or S deficiency. Also, tissue plasminogen activatorcan be deficient. Plasminogen activator inhibitor can be increased.Congenital dysfibrinogenemiaThis rare autosomal dominant disorder may cause either thrombosis or hemorrhage.

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The prominent folds of endometrium in this uterus opened to reveal the endometrial cavity are an example of hyperplasia. Cells forming both the endometrial glands and the stroma have increased in number. As a result, the size of the endometrium has increased. This increase is physiologic with a normal menstrual cycle.

Menstrual cycle                                        From Wikipedia, the free encyclopedia                       

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Menstrual cycle


The menstrual cycle is a recurring cycle of physiologic changes that occurs in the females of several mammals, including human beings and other apes.[1] Humans are the only species that has a menstrual cycle with concealed ovulation. Other placental mammals experience an estrus, or heat, where imminent ovulation is signaled to the males of the species.
The menstrual cycle is under the control of the hormone system and is necessary for reproduction. This article concentrates on the menstrual cycle as it occurs in human beings.

[ 本帖最后由 zhangheng1020 于 2007-11-6 17:45 编辑 ]

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http://library.med.utah.edu/WebPath/CINJHTML/CINJ016.html

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reference for my review


[ 本帖最后由 zhangheng1020 于 2007-11-7 17:08 编辑 ]

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RAPID COMMUNICATION
A Lethal Disease Model for Hantavirus Pulmonary Syndrome

Histologically, the lung, liver, and spleen had the most
significant and consistent changes. All hamsters had a
mild to moderate subacute interstitial pneumonia with
intraalveolar edema, protein, and fibrin that multifocally
filled alveolar spaces and expanded alveolar septal
walls (Figs. 2c and 2d). The inflammatory component
consisted primarily of macrophages and lymphocytes
with lesser numbers of neutrophils within septal walls
and surrounded the larger blood vessels with an increased
number of alveolar macrophages in alveolar
spaces. The edema was often profound around the large
blood vessels with markedly dilated lymphatics and expansion
of the perivascular interstitium. The lungs were
mildly to moderately congested and mesothelial cells
were often hypertrophied. There was a mild to moderate
subacute hepatitis in all hamsters. Randomly scattered
throughout the parenchyma were low numbers of hyperchromatic
hepatocytes with irregular cellular borders
containing karyorrhectic debris. Increased numbers of
lymphocytes were occasionally present surrounding
larger vessels. The splenic red pulp of all hamsters was
expanded by abundant numbers of large round cells with
an increased cytoplasmic to nuclear ratio. The morphology
of these cells is consistent with that of previously
reported in human cases; however, the histogenesis has
not been fully elucidated. There were a variety of other
lesions present in this initial group of hamsters. Some of
these changes were considered background lesions
arising from autolysis after death; others warrant further
investigation.

组织学变化和镜下的描述是重点。

[ 本帖最后由 zhangheng1020 于 2007-11-7 17:20 编辑 ]

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ACUTE PANCREATITIS ASSOCIATED WITH HAEMORRHAGIC FEVER WITH RENAL SYNDROME

前面是肾和肺脏的病变。这里我们看看病毒对胰腺的影响。

[ 本帖最后由 zhangheng1020 于 2007-11-7 17:24 编辑 ]