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161.
Acute inflammatory polyradiculitis represents an uncommon peripheral nerve complication during HIV infection. The case of an HIV-seropositive patient who was admitted to hospital for a cauda equina syndrome is reported. Despite early application of anticytomegalic medication, a cytomegalovrirus (CMV) infection spread out to the central nervous system (CNS), causing the patient's death. A post-mortem examination confirmed the diagnosis of CMV-encephalomyelomeningoradiculitis. To the authors' knowledge, such a progress of a CMV-related polyradiculitis to an encephalomyelomeningoradiculitis has not yet been described. The clinical features of this case will aid in the recognition of CMV-related neurological complications, and may permit earlier and perhaps more successful treatment.  相似文献   
162.
Small cell carcinoma of the larynx is an uncommon epithelial tumor, which is the most aggressive subtype of neuroendocrine carcinomas. Because of its nonspecific clinical and radiological manifestations, the diagnosis of small cell carcinoma of the larynx is essentially based on the light microscopic examination aided by electron microscopy or immunohistochemical staining. We report a case of supraglottic small cell carcinoma accompanied by large bilateral cervical lymph node metastasis ocurring in a 70-year-old man. On CT scans, no area of low attenuation indicating necrosis was demonstrated within such large metastatic lymph nodes. We suggest that small cell carcinoma of the larynx should be included in the diagnostic considerations when a laryngeal mass is accompanied by large cervical lymph nodes without necrosis shown by CT.  相似文献   
163.
Blood pressure (BP) during siesta declines to levels similar to those of night time sleep. The objective of the study was to assess the effect of siesta on 24-h ambulatory BP (ABP) data. Two different approaches were employed for the definition of day and night periods: (1) actual patient reported day and night intervals (ACT) with siesta period analysed as a third time period; and (2) arbitrary day and night time intervals (ARB) with the presence of siesta being ignored. A total of 203 24-h ABP recordings were analysed, with a siesta during ABP monitoring reported in 154 of them. Mean siesta BP was very close to ACT night time BP. Among recordings with a siesta, ACT daytime BP was higher and night time BP lower than the corresponding ARB BPs (P < 0.001). The magnitude of night time BP drop was greater with ACT intervals, resulting in a lower percentage of non-dippers (P < 0.001). Among 49 recordings without a siesta, differences between ACT and ARB BPs were less pronounced for daytime but not for night time. Differences in the magnitude of nocturnal BP drop between ACT and ARB periods, although statistically significant, did not affect the prevalence of non-dippers. In conclusion, analysis of 24-h BP profiles by using ARB instead of ACT day and night intervals results in underestimation of the nocturnal BP drop and overestimation of the proportion of non-dippers. This bias is more pronounced in patients who take a siesta during ABP monitoring.  相似文献   
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Shiga-like toxin type I (SLT-I) is a cytotoxin produced by certain strains of Escherichia coli. SLT-I is a bipartite molecule comprised of A (SLT-IA) and B (SLT-IB) subunits. In holotoxin, five B subunits are arranged in a pentameric ring and bind to globotriaosylceramide receptors on the surface of susceptible eukaryotic cells. The SLT-IB pentamer is noncovalently associated with one A subunit that has N-glycosidase activity and ultimately causes the death of targeted cells. Using a previously described overexpression vector, plasmid SBC32, we developed a two-step procedure for the purification of biologically active recombinant SLT-IB. Periplasmic proteins were extracted from E. coli JM105(pSBC32), fractionated by ammonium sulfate precipitation, and separated by isoelectric focusing in a pH 3-10 gradient. SLT-IB was present in fractions with pH values between 5.0 and 6.0, consistent with its reported pI of 5.8. SLT-IB was purified to homogeneity in a second step by native polyacrylamide gel electrophoresis. Purified SLT-IB was characterized for biological and biochemical activity. When analyzed by native polyacrylamide gel electrophoresis, the majority of SLT-IB had an apparent molecular weight of 38,900, consistent with a pentameric subunit association. Chemical cross-linking of SLT-IB with disuccinimidyl suberate resulted in species with molecular weights corresponding to dimeric, trimeric, tetrameric, and pentameric forms of B subunit. SLT-IB was not cytotoxic to Vero cells at concentrations as high as 10 micrograms/ml and protected Vero cells from native SLT-I. Purified SLT-IB maintained its ability to associate with SLT-IA to form holotoxin that exhibited toxicity similar to native toxin.  相似文献   
168.
Erythromycin, an antibiotic commonly used topically in the treatment of acne, is unstable in solution. The stability is influenced by the pH and by the presence of water. The influence of the pH on the stability of erythromycin was investigated even with the use of dimethyl isosorbide as co-solvent instead of water. The addition of zinc was attempted to ameliorate erythromycin stability as suggested in the literature. To investigate these three factors and their interactions, an optimization technique was carried out consisting of a 2(3) factorial analysis and a rotative central composite design. The erythromycin solutions were analysed with an HPLC method. The pH and the concentration of dimethyl isosorbide had a significant influence on the stability of erythromycin but the addition of zinc was not a significant factor. Moreover, there was a significant interaction between the pH and dimethyl isosorbide.  相似文献   
169.
The angiotensinogen gene is one of the very few related by linkage analysis to human hypertension, but the linkage has been consistently shown only among males. Moreover, polymorphisms in this gene predict an abnormal renal responsiveness to angiotensin II, a feature of non-modulation, but again, only among males. To pursue these related bridges between genetics and physiology, we evaluated the effects of sex on a second feature of non-modulation, the aldosterone response to infused angiotensin II during low sodium balance. We tested the resultant hypothesis-that non-modulation would be less frequent in women-by conducting identical protocols on 225 hypertensive inpatients (70 women, 155 men). Non-modulation was strikingly less frequent among women (26%; 95% confidence interval, 16% to 37%) than men (49%; 95% confidence interval, 40% to 57% (P = .001). We tested the hypothesis that sex steroids play a role by comparing young, premenopausal women (< 35 years) with women who were perimenopausal (45 to 55 years) and postmenopausal (> 55 years). Among the youngest women, the frequency of non-modulation was only 7%, significantly less than in young men (41%, P = .02). A steady increase in non-modulation frequency accompanied advancing age in women, reaching 47% in those older than 55 years, equal to the fraction of men affected. Age influenced non-modulation frequency in men far less. We conclude that a striking sex difference underlies the non-modulation phenotype and that female sex hormones may confer protection against a genotypic predisposition in women. This "override" of genotype, manifest by a very low frequency of non-modulation in young women, may participate in their known protection against cardiovascular disease.  相似文献   
170.
The study was aimed to reveal the character of interaction between the frontal and parietal areas of both brain hemispheres in patients with epileptic foci either in the frontal or parietal cortical areas. Right-handed patients were examined. Clinical, bioelectrical, and psychological techniques were applied. Functional relation between the frontal and parietal areas of the contralateral hemispheres were established on the basis of the obtained results. It is substantiated in the paper that described phenomenon of interhemispheric "criss-cross" is not pathognomonic for epilepsy. It reflects one of the forms of the brain functional plasticity aimed to organization of integrative brain activity at the new level.  相似文献   
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