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151.

Background  

Pneumococcal diseases remain a major cause of morbidity and mortality worldwide. Updated data on drug-resistance from different populations may be important to recognize changes in disease patterns. This study assessed current levels of penicilin resistance among Streptococcus Pneumoniae causing pneumonia in Spanish middle age and older adults.  相似文献   
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We review the association between surgically resolvable aortic disease and horseshoe kidney with a discussion of diagnostic problems and therapeutic options.Male patient 81 years of age with horseshoe kidney and an abdominal aortic aneurysm that was discovered by chance in an abdominal ultrasound during a check-up for his prostate condition.A retroperitoneal approach was used in order to resect the aneurysm and perform an aorto-aortic bypass with no complications occurring. Two years after the diagnosis, the patient is still asymptomatic from a vascular point of view.The co-presence of horseshoe kidney and aortic disease needing surgical correction is infrequent, but it significantly increases the technical complexity of aortic reconstruction. A literature review is included.  相似文献   
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Adipose tissue fatty acid composition, serum lipid profile, and dietary intake of 37 patients on maintenance hemodialysis were studied. In August 1982, 1984, and 1986, analyses were carried out in 15 normotriglyceridemic (NTG) and 22 hypertriglyceridemic (HTG; type IV hyperlipidemia) patients. No correlations were found between dietary intake of polyunsaturated fatty acids (PUFAs), ratio of polyunsaturated to saturated fatty acids (P-S ratio), and carbohydrate content on the one hand and serum lipid concentrations on the other in the two groups. Adipose tissue linolenic acid correlated negatively with serum cholesterol in both groups. Strong correlations were found between dietary intake of PUFAs and adipose tissue linoleic acid content, between PUFAs and the double-bond index, between P-S ratio and adipose tissue linoleic acid content, and between P-S ratio and the double-bond index. No significant differences in dietary intake or adipose tissue fatty acid composition were observed between NTG and HTG patients. Thus, no evidence was found for exogenous dietary influences on serum lipid concentrations. The adipose tissue linoleic acid content did reflect the dietary intake of PUFAs.  相似文献   
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OBJECTIVE.--To determine behavioral and demographic risk factors for human immunodeficiency virus (HIV) infection in central Africa. DESIGN.--Cross-sectional survey. SETTING.--Kigali, Rwanda. PARTICIPANTS.--A representative sample of 1458 childbearing women aged 19 to 37 years who were recruited from outpatient prenatal and pediatric clinics at the only community hospital in the city. MAIN OUTCOME MEASURE.--Antibodies to HIV assessed by enzyme immunoassay and confirmed by Western blot or indirect immunofluorescence. RESULTS.--The HIV seroprevalence was 32% overall. Infection rates were higher in women who were single, in those in steady relationships that began after 1981, and in the 33% of women reporting more than one lifetime sexual partner. Women in legal marriages or monogamous partnerships had lower rates of infection, but even low-risk women had prevalences on the order of 20%. History of venereal disease in the past 5 years, although the strongest risk factor in a multiple logistic analysis (odds ratio, 2.7; 95% confidence interval, 2.0 to 3.7), was reported by only 30% of those infected. Having a male sexual partner who drank alcohol or who had higher income were significant risk factors for HIV infection in the multivariate analysis, but use of oral contraceptives and having an uncircumcised partner were not. CONCLUSIONS.--The epidemic of the acquired immunodeficiency syndrome in Rwanda has spread beyond high-risk groups to the general population of women without known risk factors. For most of these women, a steady male partner is the source of their HIV risk and therefore a vital target for intervention efforts.  相似文献   
158.
In previous studies it was observed that endodontic silver cones placed in fine canals became dislodged as a result of corrosion. To investigate the corrosion of high purity silver, potentiostatic and potentiodynamic electrochemical techniques were used. Triangular potential sweeps made in physiological solutions and human plasma showed similar potential-current relationships. However, in human plasma, peak currents were lower and peak potentials were more anodic than those observed in the physiological solutions. The electron microprobe analysis and the EDAX of the film formed in the biological fluids revealed the presence of silver and chloride and a certain amount of carbon. The addition of small quantities of Na2S to the physiological solutions favoured metal dissolution and promoted the formation of a mixed film of AgCL and Ag2S. According to these results chloride and sulphide anions seem to be particularly aggressive towards the metal surface in implanted silver cones. Precautions to avoid direct contact of the cones with saliva and tissue fluids must be taken. Fractures and discontinuities present in the cement considerably increase the corrosion risks.  相似文献   
159.
A percentage of human T lymphocytes forms rosettes with autologous erythrocytes and this property has been considered as a marker for post-thymic precursor suppressor cells capable of providing suppression under the influence of inducer cells. We quantitated autologous rosette-forming T cells (ARFC) in the peripheral blood of 37 patients with chronic HBV infection: 8 healthy carriers, 9 chronic persistent hepatitis (CPH-B) and 20 chronic active hepatitis (CAH-B). Two control groups were studied, one consisting of 26 healthy individuals and the other of 8 individuals with non-HBV-associated CAH. Patients with non-HBV-associated CAH had a significant reduction in the proportion of ARFC, whereas CAH-B patients fell into 2 distinct patterns, one with increased and the other with decreased proportions of ARFC. This was unrelated to the degree of biochemical activity of the disease or to degree of viral replication as defined by HBeAg status and HBV-DNA in the serum. Healthy carriers and CPH-B had no changes in ARFC. Simultaneous quantitation of OKT4 and OKT8+ cells was done and a positive correlation was found between the proportions of ARFC and the proportions of OKT8+ cells. The possible significance of this correlation and the relevance of the bimodal distribution of autologous rosette-forming cells in CAH-B are discussed.  相似文献   
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