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21.
    
Diarrhea is a non-specific symptom which may be associated with Addison's disease and several causes had been demonstrated in the aetiology. We describe a patient with Addison's disease who was suffering from chronic diarrhea for three months. She was diagnosed as having collagenous colitis and successfully treated with Sulphasalazine, 2 g/day. Collagenous colitis is an uncommon cause of chronic diarrhea and the association of collagenous colitis with Addison's disease has not previously been described. We think that collagenous colitis may play a role in the aetiology of diarrhea in patients with Addison's disease and therefore we suggest a full colonoscopic examination in other patients with Addison's disease and diarrhea to determine the incidence of collagenous colitis in the aetiology of diarrhea.  相似文献   
22.
    
The visitation committee medicine and health studies in 1997 visited all eight Dutch medical schools. A quality judgement was formed based on the results of a self-analysis of these schools and extensive research on the spot. The conclusion was that all schools inspected turn out physicians who can be trusted to do their work well. However, the committee judges the curricula of some of the schools to be very traditional: too much oriented towards the basic sciences with hardly any room for contributions of the students themselves.  相似文献   
23.
    
The presence of the neuropathological alterations of Alzheimer's disease (AD) in essentially all older Down syndrome (DS) patients suggests that the examination of younger DS patients may clarify the early pathological progression of AD. We examined the hippocampus and parahippocampal-inferior temporal gyri of 42 DS patients (ages 4 days to 38 years) for the deposition of amyloid beta protein (Abeta) using both a modified Bielschowsky stain and immunohistochemistry for Abeta protein. The parahippocampal and inferior temporal gyri demonstrated Abeta staining in cases as young as 8 years of age. As age and degree of Abeta deposition increased, staining included the CA-1/subiculum and dentate molecular layer followed then by the remainder of the CA hippocampal regions. The first neuritic plaques were observed in the CA-1/subiculum, despite this being a later region of Abeta deposition. Although Abeta staining increased with age, there was substantial variability in the severity of Abeta deposition within age groups. These results suggest that within the hippocampal/parahippocampal region there is a progressive stereotypic deposition of Abeta. The variable severity of Abeta deposition within age groups suggests that other factors, besides DS, may be contributing to the timing and severity of Abeta deposition.  相似文献   
24.
    
OBJECTIVE: The authors describe new ocular and electroretinographic (ERG) features in Menkes disease. DESIGN: The study design is a case report. PARTICIPANTS: The authors studied two patients with Menkes disease. INTERVENTION: The authors performed complete ophthalmologic and ERG evaluations in both patients. MAIN OUTCOME MEASURES: The parameters used were slit-lamp biomicroscopy and ERG recordings. RESULTS: Aberrant lashes and anterior stromal hypoplasia of the iris are new findings, and profound delays in b-wave implicit time in well-developed photopic responses may be added as new ERG features. CONCLUSIONS: Patients with Menkes disease may have aberrant lashes, anterior stromal hypoplasia, and retinal degeneration.  相似文献   
25.
    
Macrophage activation and tumor necrosis factor-alpha (TNF-alpha) production are critical in tuberculosis immunity but may result in increased human immunodeficiency virus (HIV) expression and accelerated HIV disease progression in HIV-infected persons. Pentoxifylline inhibits expression of TNF-alpha and HIV. A double-blind, placebo-controlled study of adjunctive therapy with pentoxifylline (1800 mg/day) as a timed-release formulation was done in Ugandan HIV-infected patients with pulmonary tuberculosis. Subjects had early HIV disease (mean CD4 cell count, 380/microL) and did not receive other antiretroviral drugs. Pentoxifylline resulted in decreased plasma HIV RNA and serum beta 2-microglobulin and, in a subset of moderately anemic patients, improved blood hemoglobin levels. Trends were noted toward reduced TNF-alpha production in vitro and improved performance scores, but these did not reach statistical significance. No effect was noted on body mass, CD4 cell count, or survival. Additional studies of more potent TNF-alpha inhibitors in HIV-positive subjects with tuberculosis are warranted.  相似文献   
26.
    
A randomized double-blind, placebo-controlled study was performed to determine the safety, efficacy, and effect of thalidomide on a variety of immunological and biochemical parameters in asymptomatic human immunodeficiency virus (HIV)-positive patients. Nineteen male patients with elevated markers of immune activation and CD4 cell counts above 400/mm3 were randomized to either placebo or thalidomide at 100 mg/day for 24 weeks. However, only 3 (of 10) patients receiving thalidomide completed all 24 weeks compared to 6 (of 9) patients receiving placebo. This was mainly due to fatigue (somnolence is a recognized side effect), although this was also seen to a lesser extent in the placebo group and so may not be drug attributable. No significant changes in CD4/CD8 count, activation markers, TNF-alpha, or TNFR1 were observed. However, a nonsignificant trend toward inhibition of mitogen-induced TNF-alpha production was observed in the thalidomide arm. The lack of systemic effect and the lower tolerance of thalidomide (at this dose) in asymptomatic patients highlights the need for pharmacokinetic analysis to address possible absorption problems and the need for more potent and less toxic TNF-alpha inhibitors to be developed for use in this type of study.  相似文献   
27.
    
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28.
    
A novel method was developed to evaluate the acrosomal status of mammalian spermatozoa. The method is based on the ability of the lectin Pisum sativum agglutinin (PSA) to bind specifically to glycoproteins of the acrosomal matrix released during the acrosome reaction. The amount of released acrosomal content is proportional to the fraction of spermatozoa that underwent acrosome reaction. The released glycoproteins present in the supernatant separated from the cells were detected via an ELISA-like assay. The authors suggest that one of these glycoproteins might be the acrosin as identified by anti-acrosin antibodies, using Western blot analysis. The new method (demonstrated here with ram and bull spermatozoa) correlates well with the results obtained by conventional methods. Its advantages are simplicity, objectiveness, rapidity, and low cost. In addition, many samples can be processed in parallel. The method can be used in experimental as well as clinical applications.  相似文献   
29.
    
The four isomers of 4-aminopyrrolidine-2,4-dicarboxylate (APDC) were prepared and evaluated for their effects at glutamate receptors in vitro. (2R,4R)-APDC (2a), an aza analog of the nonselective mGluR agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate (1S,3R)-ACPD, 1), was found to possess relatively high affinity for metabotropic glutamate receptors (mGluRs) (ACPD-sensitive [3H]glutamate binding IC50 = 6.49 +/- 1.21 microM) with no effects on radioligand binding to NMDA, AMPA, or kainate receptors up to 100 microM. None of the other APDC isomers showed significant mGluR binding affinity, indicating that this interaction is highly stereospecific. Both 1 and 2a were effective in decreasing forskolin-stimulated cAMP formation in the adult rat cerebral cortex (EC50 = 8.17 +/- 2.21 microM for 1; EC50 = 14.51 +/- 5.54 microM for 2a); however, while 1 was also effective in stimulating basal tritiated inositol monophosphate production in the neonatal rat cerebral cortex (EC50 = 27.7 +/- 5.2 microM), 2a (up to 100 microM) was ineffective in stimulating phosphoinositide hydrolysis in this tissue preparation, further supporting our previous observations that 2a is a highly selective agonist for mGluRs negatively coupled to adenylate cyclase. Microelectrophoretic application of either 1 or 2a to intact rat spinal neurons produced an augmentation of AMPA-induced excitation (95 +/- 10% increase for 1, 52 +/- 6% increase for 2a). Intracerebral injection of 1 (400 nmol) produced characteristic limbic seizures in mice which are not mimicked by 2a (200-1600 nmol, ic). However, the limbic seizures induced by 1 were blocked by systemically administered 2a in a dose-dependent manner (EC50 = 271 mg/kg, ip). It is concluded that (2R,4R)-APDC (2a) is a highly selective, systemically-active agonist of mGluRs negatively coupled to adenylate cyclase and that selective activation of these receptors in vivo can result in anticonvulsant effects.  相似文献   
30.
    
Hepatocellular carcinoma is an uncommon complication of primary biliary cirrhosis. Hepatocellular carcinoma occurs generally in the end stage of the disease. We report a case of asymptomatic primary biliary cirrhosis complicated by a hepatocellular carcinoma in a 66 year-old man.  相似文献   
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