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71.

Background  

Lipid rafts have been shown to play a role in T cell maturation, activation as well as in the formation of immunological synapses in CD4+ helper and CD8+ cytotoxic T cells. However, the differential expression of lipid raft components between CD4+ and CD8+ T cells is still poorly defined. To examine this question, we analyzed the expression of GM1 in T cells from young and aged mice as well as the expression of the glycosylphosphatidylinositol (GPI)-linked protein Thy-1 and cholesterol in murine CD4+ and CD8+ T cell subpopulations.  相似文献   
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Transplantation of any organ has some inherent risk of disease transmission, such as infection and malignancy. The present study aims to describe 2 cases of choriocarcinoma transmission after kidney and liver transplantation originating from the same patient. The donor was a 17-year-old woman who died of cerebral hemorrhage. Both organ recipients died of metastatic choriocarcinoma few months after the transplantation, within days after starting chemotherapy. Retrospective hCG (human chorionic gonadotropin hormone) analysis in donor's blood stored at the time of donation had a result of 9324 mIU/mL. Despite its rarity, clinicians should be aware of the risk of transplant-related choriocarcinoma from female donors in childbearing age. In some cases, hCG dosage should be performed before donation.  相似文献   
74.
BackgroundIntrahepatic lithiasis (IHL) is a rare disease in the western world. Complications associated with IHL include acute cholangitis, liver atrophy, secondary biliary cirrhosis, and risk for intrahepatic cholangiocarcinoma. Liver resection is considered the treatment of choice for IHL. The objective of this study was to analyze patients who underwent liver resection for non-Asian hepatolithiasis.Methods127 patients with symptomatic non-Asian hepatolithiasis underwent resection in six institutions. Demographic data, clinical presentation, diagnosis, classification according to stone location, presence of atrophy, bile duct stricture, biliary cirrhosis, incidence of cholangiocarcinoma, treatment and postoperative course were evaluated.Results52 patients (40.9%) were male and the mean age was 46.1 years. Sixty-six patients (51.9%) presented with history of cholangitis. Stones were located in the left lobe in 63 (49.6%), and right lobe in 28 patients (22.0%). Atrophy was observed in 31 patients (24.4%) and biliary stenosis in 18 patients (14.1%). The most common procedure performed was left lateral sectionectomy in 63 (49.6%) patients, followed by left hepatectomy in 36 (28.3%), right hepatectomy in 19 (15.0%), and associated hepaticojejunostomy in 28 (22.0%). Forty-two patients (33.0%) presented postoperative complications and the most common were biliary fistula (13.3%) and surgical site infection (7.0%). Postoperative mortality was 0.7%. Intrahepatic cholangiocarcinoma was observed in 2 patients (1.5%). Recurrence was identified in 10 patients (7.8%), mostly with bilateral stones and/or hepaticojejunostomy.ConclusionLiver resection is the standard treatment for symptomatic unilateral or complicated IHL with good operative results. Risk of cholangiocarcinoma was low in non-Asian patients.  相似文献   
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76.
BackgroundObstructive sleep apnea–hypopnea syndrome (OSAHS) is present in 80% of patients evaluated for bariatric surgery (BS). Extensive evaluation is not widely available, but treatment is mandatory for severe cases. The Snore, Tiredness, Observed apneas and Pressure - Body mass index, Age, Neck circumference and Gender (STOP-Bang) and Epworth questionnaires and neck-to-height ratio (NHtR) are accessible clinical tools to screen for sleep and metabolic disturbances, but their utility to detect severe OSAHS in patients with severe obesity has not been determined.ObjectivesTo evaluate the cutoff point of those clinical tools that may predict severe OSAHS, confirmed by polysomnography in patients referred for BS.SettingTertiary referral center in Mexico City.MethodsWe applied the STOP-Bang and Epworth questionnaires, evaluated anthropometric characteristics, and collected samples for arterial gasometry and metabolic parameters from 68 patients with severe obesity, who were then referred for polysomnography before their evaluation for BS.ResultsOf the 68 patients participating in the study, 67.7% were female, with a median age of 43 years (35–49 years) and a body mass index (BMI) of 45.5 kg/m2 (42.4–50.9 kg/m2; 28.3% had a BMI ≥ 50 kg/m2). A STOP-Bang cutoff >5 points had a sensitivity of 60% and specificity of 90% for detecting severe OSAHS (area under the curve [AUC] = .962); meanwhile, an NHtR >.25 had a sensitivity of 90% and specificity of 52.5% (AUC = .759). The Epworth scale score >11 points had a sensitivity of 57.1% and specificity of 83.3% (AUC = .802).ConclusionClinical data may be useful to detect severe sleep apnea in high-risk populations, allowing for rapid referral and better use of resources.  相似文献   
77.
Summary The effects of changes in oxygen supply and oxygen demands on fiber cross-sectional areas, capillary dersities and capillary to fiber ratios were determined in three skeletal muscles of rat. The muscles examined were the vastus lateralis, soleus, and diaphragm. Reduced oxygen supply was produced by subjecting rats to ambient hypoxia, and increased oxygen demands were produced by subjecting rats to low ambient temperatures or treatment with thyroxin. Capillaries were visualized by injecting fluorescent dyes into the circulation. Muscles were quick frozen at resting lengths to preserve normal fiber geometry and were subsequently sectioned on a cryostat. All of the muscles sampled from animals in the experimental groups had elevated capillary densities. However, capillary to fiber ratios were not increased significantly in any muscle, for any experimental condition. Thus, all of the observed differences in capillarity were due to changes in the intrinsic rate of muscle fiber growth. Further, the relations of capillary density and capillary to fiber ratio to fiber area were the same as those obtained during normal maturation, suggesting that capillary growth is closely linked to the intrinsic rate of fiber growth.  相似文献   
78.
Between 1953 and 1989 eighty cases of non-traumatic brain abscess were treated in our department. We have re-examined the clinical and neuroradiological features of this pathological process and present our therapeutic approach and results. We believe that the optimal treatment for brain abscess consists of surgical removal.The prognosis for these lesions has undergone a marked improvement over the last two decades in response to neuroradiological, microbiological and surgical advances. The most influential prognostic factor seems to be preoperative clinical status.  相似文献   
79.
Objectives To investigate the potential advantages of epidural anesthesia in an in vitro fertilization and embryo transfer program.Study Design Between January 1991 and December 1992, 148 infertile patients underwent transvaginal ultrasound guided oocyte retrieval. A total of 44 patients (group A) had 50 retrievals under epidural anesthesia, and 104 patients (group B, control group) 112 retrievals under intravenous sedation (propofol) with mask-assisted ventilation (nitrous oxide).Results In group A satisfactory anesthesia was achieved in 49 of the 50 cases (98%); one patient required additional intravenous administration of propofol owing to extreme anxiety. No complications were observed. Adversely, in group B nausea was observed in 16 cases (14%) and nausea and vomiting in 7 cases (6%). In group A the fertilization, cleavage and pregnancy rates were 67.2%, 92% and 20% respectively, while in group B the rates were 69.3%, 93% and 19.6% respectively; the differences are not statistically significant.Conclusions Epidural anesthesia is an effective method for transvaginal oocyte retrieval but does not improve the treatment outcome as compared to an intravenous sedation with mask-assisted ventilation using propofol and nitrous oxide.  相似文献   
80.
The bioequivalence of recombinant human growth hormone (rhGH) (somatropin) and its N-methionyl variant (Met-hGH) [Protropin((R)) (somatrem for injection)] was determined in 42 healthy male volunteers (n = 21 per treatment) who were randomized to receive either protein by subcutaneous administration of 0.1 mg kg(minus sign1). Serum samples were collected over 24 h after the injection, and the concentration of human growth hormone (hGH) were determined by an immunoradiometric assay. Bioequivalence of the two proteins was assessed by determining whether the 90% confidence limits for the ratio of geometric means using logarithmically transformed AUC and C(max) parameters (log(10)AUC(0--24), log(10)AUC(0--infty infinity), and log(10)C(max)) were within the 80--125% range. The bioequivalence of the two treatments was also tested by calculating a bioequivalance index (xi(2)) that measured the difference between the two mean concentration-time profiles. The 90% confidence intervals for the ratios of the geometric means for AUC were within the prescribed 80--125% range for bioequivalence. The upper limit of the 90% confidence interval for the ratio of the geometric means for C(max) fell slightly outside the 125% criterion even though the geometric mean itself, 106.6%, was very close to the ideal of 100%. There was a larger standard error associated with C(max) than with the AUCs, and this marginally larger confidence limit for C(max) resulted more from the variance among the subject than to the difference in the means. In fact, the bioequivalence index, xi(2), was 0.075, indicating that the mean curves after rhGH and Met-hGH are essentially superimposable.  相似文献   
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