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1.
神经生长因子对小鼠突触体内Ca^2+水平的调节作用 总被引:4,自引:1,他引:3
观察了多次海马内微注射NGF对小鼠突触体内游离钙水平的影响,并在离体情况下观察NGF对EGTA和CaCl2分别造成突触体内低钙和高钙状态的调节作用。结果如下:(1)在体实验表明,一定剂量的NGF可显著降低老年小鼠海马突触体内游离钙水平(P<005);(2)离体实验表明,当突触体游离钙水平降低时,适当剂量的NGF具有升高游离钙水平的作用;而突触体内游离钙水平升高时,则NGF有降低游离钙水平的作用。提示NGF对游离钙水平的双向调节作用可能是NGF改善老年性记忆衰退的作用机制。 相似文献
2.
In 1988, a cross-sectional survey was carried out in the Romagna region (Italy) to evaluate the association between knowledge of breast pathophysiology and preventive attitudes and screening tests practice for breast cancer. A self-administered questionnaire was distributed to a sample of asymptomatic women aged 20-64 years living in the city of Faenza (Northern Italy). Of the 657 responders, 58% reported that they practiced breast self-examination; 55% had had a professional breast examination, and only 9% had had a mammogram as a screening test. Logistic regression analysis (including variables such as age, education, employment) was performed to explore the relationship between screening tests practice and factors associated with their use. Breast self-examination practice (n = 590) was associated with preventive attitudes (aOR = 1.67, 95% CI = 1.09-2.53) and with a positive history of breast disease (aOR = 3.48, 95% CI = 1.72-7.04). Professional breast examination (n = 480) was related to preventive attitudes (aOR = 2.37, 95% CI = 1.51-3.71), knowledge of breast pathophysiology (aOR = 2.07, 95% CI = 1.31-3.28), and use of oral contraceptives (aOR = 1.81, 95% CI = 1.12-2.91). Mammography use (n = 540) was associated with preventive attitudes (aOR = 3.08, 95% CI = 1.40-6.76). The results show an inadequate utilization of screening tests in our population. Breast self-examination is strongly related to a positive history of breast disease, and this could reflect the lack of health educational programs aimed at the general population. 相似文献
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A congenital defect of the scrotal wall with consequent testicular exstrophy is an exceptional finding. The etiopathogenesis of this defect is debated. We report a newborn male with arthrogryposis who presented with an exstrophied testicle. The association of these two conditions seems to establish a cause-effect relationship mediated by mechanical factors, i.e., in utero compression of the scrotum by the feet. It is likely that a similar mechanism could also be advocated to explain the previous cases reported in the literature. 相似文献
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Alberto Salinas M.D. Harry M. Salinas B.Sc. Edwin Santiago Ph.D. Wilfredo García M.D. Queta Ferro R.D. Mariemma Antor M.Sc. 《Surgery for obesity and related diseases》2009,5(4):455-458
BackgroundSilastic ring vertical gastric bypass (SRVGB) with jejunal interposition is our standard operation for morbidly obese patients. We present the results of 5 years of follow-up in a cohort of patients who underwent SRVGB in 2001.MethodsThe records of all 160 consecutive patients who underwent SRVGB from January to December 2001 were reviewed. Of the 160 procedures, 143 were primary open cases, 14 were revisions from restrictive procedures, and 3 were laparoscopic cases. At 5 years, the body mass index and percentage of excess weight loss was available for 133 patients (83%) at office visits (n = 91, 68.4%), by telephone (n = 40, 30.1%), or by e-mail (n = 2, 1.5%).ResultsOf the 160 patients, 121 were women and 39 were men, with a mean age of 33.15 ± 10.0 years, percentage of ideal body weight of 195.7% ± 40.8%, and body mass index of 44.6 ± 9.3 kg/m2. The mean hospital stay was 3 ± 1 days. One patient (.6%) died of a pulmonary embolus. Early complications included 3 cases (1.87%) of upper gastrointestinal bleeding and 4 gastric leaks (2.5%): 2 (1.36%) from primary cases and 2 (14.29%) from revisional cases. Late complications included 32 patients (20%) with incisional hernias, 20 (12.5%) with anemia, 14 (8.8%) with dumping, 4 (2.5%) with gastrojejunal stricture, 2 (1.25%) with intestinal obstruction, and 2 (1.25%) requiring silastic ring surgical removal. The 5-year follow-up data were available for 133 patients (83%). The mean body mass index in this group was 27 ± 5 kg/m2, with a percentage of excess weight loss of 83% ± 18.3% at 5 years postoperatively.ConclusionThe results of our study have shown that SRVGB is an effective operation for promoting lasting weight loss, with acceptable mortality and complication rates. 相似文献
7.
The serum prostate-specific antigen (PSA) of 58 men with benign prostatic hypertrophy (BPH) and 17 men with carcinoma of the prostate (CaP) was correlated with the weight of prostatic tissue resected at transurethral prostatectomy (TURP). A significant correlation was identified between the weight of resected BPH tissue and the serum PSA (p less than or equal to 0.001; r = 0.54). No such correlation was seen in the CaP patients. By arbitrarily dividing the serum PSA by the prostate weight, it was possible to devise an index. This index corrected PSA in relation to prostatic size and unlike PSA in isolation did not differ significantly between normal controls and those with BPH. The index in CaP was significantly greater than that of either controls or BPH (p less than or equal to 0.001). Furthermore the index of metastatic CaP (M1) was significantly higher than that of nonmetastatic disease (MO) (p = 0.05). The higher index found in CaP would seem to be related to the bulk metastatic tumor, either manifest or occult. Comparing the index of CaPs to that found in normal and benign disease (a constant) offers a possible means of estimating the extent of local and metastatic tumor mass. 相似文献
8.
Distribution of Hepatitis B Virus Genotypes in Two Different Pediatric Populations from Argentina 总被引:12,自引:2,他引:10
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V. A. Mbayed J. L. Lpez P. F. S. Telenta G. Palacios I. Badía A. Ferro C. Galoppo R. Campos 《Journal of clinical microbiology》1998,36(11):3362-3365
Differences in pathogenesis and the probability of becoming a chronic carrier depend on the age at which hepatitis B virus (HBV) infection is acquired, ranging from 82% in infants less than 6 months of age to 15 to 30% in older children. HBV genotypes from 22 pediatric patients from two areas that differ in prevalence have been determined. Phylogenetic analysis shows a clear difference between the genotype distribution in Buenos Aires, a low-prevalence area, and that found in Gualeguay, Entre Ríos, a high-prevalence area. While the analysis allocated the sequences in the Buenos Aires group to genotypes A (36%), D (9%), and F (55%), the Gualeguay group presented exclusively genotype A isolates with very low nucleotide divergence, which suggests a strong founder viral population. The high prevalence of genotype F in the Buenos Aires group and its high intragroup heterogeneity agree with the American origin of this genotype. 相似文献
9.
L. Simonato J. J. Moulin B. Javelaud G. Ferro P. Wild R. Winkelmann R. Saracci 《American journal of industrial medicine》1994,25(5):625-633
A historical mortality study of a cohort of employees of a gold mining and refining company was carried out in Salsigne, France. A major goal of the study was to investigate the relationship between lung cancer mortality and exposure to arsenic, radon, silica, and other contaminants of the working environment. A twofold excess of lung cancer was found both among miners and smelters, mainly concentrated among workers who had experienced exposure to past levels of arsenic, radon, and silica. The consistency of the results in the mine and the refinery are suggestive of a carcinogenic risk from both soluble and insoluble arsenic, although the potential role of other factors cannot be dismissed. © 1994 Wiley-Liss, Inc. 相似文献
10.
MY Mancao LJ Sindel PH Richardson FM Silver 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(1):118-120
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup. 相似文献