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91.
石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。  相似文献   
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The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding.  相似文献   
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Tuberculosis is a public health problem. The most common presentation is pulmonary disease. The diagnosis of any extrapulmonary forms are quite difficult. Clinical manifestations of gastrointestinal tuberculosis are non-specific and compatible with pathologies such as inflammatory bowel disease, advanced ovarian cancer, deep mycosis, yersinia infection and amebomas. Abdominal form is located at 6th place of the extrapulmonary forms, after lymphatic, genitourinary, osteoarticular, miliary and meningeal infections. Eventually, 25 to 75% of patients with abdominal tuberculosis will require surgery. These procedures should be limitated with the purpose to preserve small bowel. Resection should be limitated for complicated cases. The surgical indications include: Intestinal occlusion (15-60%), perforation (1-15%), abscesses and fistulas (2-30%) and hemorrhage (2%). CONCLUSIONS: In most of the cases, the diagnosis of peritoneal or intestinal tuberculosis is made during a laparoscopy or laparotomy even during surgery performed by different purposes. Excessive manipulation of the intraabdominal organs may produced unexpected bowel lesions, increasing morbidity and mortality. Medical treatment is highly effective in the resolution of moderate complications such as bowel obstruction. Resectional procedures should be reserved for complications like perforation, bleeding or stenosis non-suitable for stricturoplasty.  相似文献   
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BACKGROUND: Corynebacterium urealyticum is a cause of urinary tract infection and encrusting cystitis or pyelitis. Information about this infection in renal transplant recipients is based on case reports. We communicate the first prospective epidemiological study for this population. METHODS: We selected a cohort of 163 renal transplant recipients who were screened for urinary tract infection due to C. urealyticum. Long-term incubation and special media were used for culture of C. urealyticum. The cohort was observed for a mean of 26.2 months (standard deviation, 8.7; range, 1-36 months). Risk factors and outcomes were assessed. RESULTS: At baseline, 16 (9.8%) of 163 patients had C. urealyticum bacteriuria (6 were asymptomatic, 9 had acute cystitis, and 1 had encrusting pyelitis). Independent risk factors (assessed by multivariate analysis) for urinary tract C. urealyticum infection were: antibiotic administration during the previous month (odds ratio, 8.04; 95% confidence interval, 1.57-41.06; P = .012), history of nephrostomy (odds ratio, 51.59; 95% confidence interval, 3.62-736.06; P = .004), and skin colonization (odds ratio, 208.35; 95% confidence interval, 21.54-2015.22; P< .001). Presence of urinary tract infection symptoms for >1 month (odds ratio, 27.7; 95% confidence interval, 2.55-300.5; P = .006) and obstructive uropathy (odds ratio 25.9; 95% confidence interval, 4.43-152.31; P < .001) were more frequent during follow-up in patients with C. urealyticum bacteriuria. CONCLUSIONS: When specifically tested for, C. urealyticum bacteriuria is more prevalent than previously thought in renal transplant recipients, and it is closely related to obstructive uropathy. Future studies are necessary to establish the relevance of treating the infection during follow-up after renal transplantation.  相似文献   
96.
We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice.  相似文献   
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Introduction: The risk of mortality from cardiovascular disease (CVD) is higher in wintertime throughout the world, but it is not known if this reflects annual changes in diet or lifestyle, or an endogenous photoperiodic mechanism that is sensitive to changes in day length.

Methods: Phenotypic data on cardiometabolic and lifestyle factors were collected throughout a 4 year time period from 502,642 middle-aged participants in UK Biobank. To assess the impact of seasonal environmental changes on cardiovascular risk factors, we linked these data to the outdoor temperature and day length at the time of assessment. Self-reported information on physical activity, diet and disease status were used to adjust for confounding factors related to health and lifestyle.

Results: Mortality related to CVD was higher in winter, as were risk factors for this condition including blood pressure, markers of inflammation and body mass index (BMI). These seasonal rhythms were significantly related to day length after adjustment for other factors that might affect seasonality including physical activity, diet and outdoor temperature.

Conclusions: The risk of CVD may be modulated by day length at temperate latitudes, and the implications of seasonality should be considered in all studies of human cardiometabolic health.

  • Key messages
  • In this cross-sectional study in UK Biobank, we report annual variations in cardiovascular risk factors and mortality that were associated with day length independent of environmental and lifestyle factors.

  • These seasonal changes in day length might contribute to annual patterns in cardiovascular disease and mortality.

  相似文献   
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