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71.
Transient global and transient focal ischemia induced the 72 kDa heat shock protein (hsp72) in neurons in cortex, striatum, and other regions known to be injured during transient ischemia. A novel finding was the induction of hsp72 in islands (cylinders in three dimensions) of cells composed of astrocytes around the perimeter and neurons in the interior. Since histology showed pale staining in these regions, it is proposed that these islands represent areas of focal infarction in the distribution of small cortical and lenticulostriate arteries. Although the factors responsible for hsp72 induction during ischemia and infarction are unknown, these results suggest differences in mechanisms of hsp72 induction in astrocytes compared to neurons.  相似文献   
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We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA.  相似文献   
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Patients with clinical signs of alpha 1-antitrypsin deficiency in the neonatal period usually present with prolonged obstructive jaundice. We report a patient with alpha 1-antitrypsin deficiency who presented with gallbladder enlargement in the neonatal period. This gallbladder enlargement may be due to cystic duct hypoplasia or atresia, which has been reported in association with alpha 1-antitrypsin deficiency. The diagnosis of alpha 1-antitrypsin deficiency should be considered in neonates with gallbladder enlargement and prolonged obstructive jaundice.  相似文献   
78.
Testing feces for occult blood is widely recommended as a means of detecting subclinical colorectal tumors. Guaiac tests such as Hemoccult® are the most widely used, but chemical sensitivity is relatively low and the tests are affected by dietary peroxidases, the state of fecal hydration, and certain drugs. The newly devised HemoQuant® and immunologic techniques appear more sensitive and specific, but they require further evaluation before widespread clinical usage can be recommended.Occult blood screening has both merits and weaknesses. Testing does uncover subclinical colorectal cancer, often at a relatively early stage, but whether this actually improves the prognosis remains to be proven. Benign neoplastic polyps are also detected, although it is debatable whether this is a valid rationale for screening. Test sensitivity for malignancy varies from good to moderate, but is poor for benign polyps. Specificity is usually around 97%–98%, yet the predictive value of a positive test for cancer is only about 10%: hence most test-positive individuals are needlessly subjected to invasive colonic investigations. Reported figures on public compliance with occult blood testing vary widely from excellent to poor. Published costs of screening are usually quite low, but these overlook important indirect and hidden expenses and are therefore misleading.On balance, the problems of occult blood testing currently appear to outweight the merits. This could change, however, with the newer testing techniques and with awaited mortality data from controlled clinical trials now underway.  相似文献   
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The prevalence for anorexia nervosa is estimated at 0.5% in the young girls and the highest incidence was found between ten to 19 years. Among women, the prevalence for anorexia nervosa is estimated between 0 to 1.5%. The lifetime prevalence varies between 0.6 and 4%. The methodological limitations relate to the variety of the instruments to diagnose an eating disorder and the lack of definition approved for eating disorders not otherwise specified. The empirical models of the pathogenesis of eating disorders continue to stress the role of social pressure to thinness, this one being transmitted by the media, the family environment and the peers. The methodological limitations continue to pose a challenge in the interpretation of the modulation by the sociocultural factors of the etiologic ways for anorexia nervosa. A complex multifactor aetiology is considered, implying the interaction of genetic predisposition and certain specific environmental risk factors, in particular social factors.  相似文献   
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A tailored proficiency test programme in high-resolution gamma-spectrometric analysis has been established for the radionuclide laboratories designated to support the verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). It entails certified reference samples that contain fission products relevant to the CTBT. The sample geometries and materials correspond to aerosol filter samples from the high-volume samplers of the radionuclide stations of the International Monitoring System (IMS) and the related calibration sources are matrix and geometry matched to the reference samples.  相似文献   
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