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71.
PURPOSE OF REVIEW: To identify recent progress and emerging problems in addressing syphilis among men who have sex with men. RECENT FINDINGS: A resurgence of syphilis has occurred among men who have sex with men in many developed countries. Infection has been associated with HIV coinfection, multiple partners, and recreational drug use. Unlike HIV, oral sex appears to be a common route of syphilis transmission. Many prevention approaches have shown, at best, modest success. Variable clinical presentation and potentially inconclusive lab tests make diagnosis confusing. SUMMARY: As the infection remains relatively rare, clinicians treating men who have sex with men should maintain a high index of suspicion for syphilis lesions, and should screen their sexually active patients for latent disease. Debates about syphilis control and treatment continue. The clinical manifestations, serologic responses, efficacy of treatment, and complications of syphilis have always been complicated. HIV coinfection adds to the confusion.  相似文献   
72.
Fatigue, pain, distress, and anorexia are four commonly encountered symptoms in cancer. To evaluate the usefulness of a single-item screening for these symptoms, 597 ambulatory outpatients with solid tumors were administered a self-report screening instrument within the first 12 weeks of chemotherapy. Patients rated the severity of each symptom on a 0-10 scale, at its worst over the past three days, with higher ratings associated with higher symptom levels. From this sample, 148 patients also completed a more comprehensive assessment of these symptoms. Two criteria were used to determine optimal cut-off scores on the screening items: 1) the sensitivity and specificity of each screening item to predict clinical cases using receiver-operating characteristics analysis and 2) the proportion of patients at each screening score who reported that some relief of the target symptom would significantly improve their life. Optimal cut-off scores ranged from 4 to 6 depending on the target symptom (area under the curve range=0.68-0.88). Use of single-item screening instruments for fatigue, pain, distress, and anorexia may assist routine clinical assessment in ambulatory oncology practice. In turn, such assessments may improve identification of those at risk of morbidity and decreased quality of life due to excess symptom burden.  相似文献   
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This study examined racial/ethnic differences in spiritual well-being (SWB) among survivors of cancer. We hypothesized higher levels of Peace and Faith, but not Meaning, among Black and Hispanic survivors compared to White survivors, differences that would be reduced but remain significant after controlling for sociodemographic and medical factors. Hypotheses were tested with data from the American Cancer Society’s Study of Cancer Survivors-II. The FACIT-Sp subscale scores, Meaning, Peace, and Faith assessed SWB, and the SF-36 Physical Component Summary measured functional status. In general, bivariate models supported our initial hypotheses. After adjustment for sociodemographic and medical factors, however, Blacks had higher scores on both Meaning and Peace compared to Hispanics and Whites, and Hispanics’ scores on Peace were higher than Whites’ scores. In contrast, sociodemographic and medical factors had weak associations with Faith scores. The pattern with Faith in bivariate models persisted in the fully adjusted models. Racial/ethnic differences in Meaning and in Peace, important dimensions of SWB, were even stronger after controlling for sociodemographic and medical factors. However, racial/ethnic differences in Faith appeared to remain stable. Further research is needed to determine if racial/ethnic differences in SWB are related to variations in quality of life in survivors of cancer.  相似文献   
76.
The motor protein Kinesin-1 drives intracellular transport along microtubules, with each of its two motor domains taking 16-nm steps in a hand-over-hand fashion. The way in which a single-motor domain moves during a step is unknown. Here, we use Förster resonance energy transfer (FRET) between fluorescent labels on both motor domains of a single kinesin. This approach allows us to resolve the relative distance between the motor domains and their relative orientation, on the submillisecond timescale, during processive stepping. We observe transitions between high and low FRET values for certain kinesin constructs, depending on the location of the labels. These results reveal that, during a step, a kinesin motor domain dwells in a well-defined intermediate position for ≈3 ms.  相似文献   
77.
冠状动脉搭桥术早期并发症及死亡率(附196例报告)   总被引:1,自引:0,他引:1  
1985年1月~1987年12月作者于荷兰格罗宁根医学科学院心胸外科主做了196例冠状动脉搭桥术。术后早期死亡2例(1.0%)、内出血3例(1.5%)、胸骨裂开2例(1.0%)、心律紊乱40例(20.4%)、围手术期心肌梗塞5例(2.6%),本文就术后早期并发症进行了讨论。  相似文献   
78.
The proximity of child's kidneys from the cutaneous surface allows a particularly sensitive exploration by doppler sonography, which in addition has the major advantage of being a non-invasive, non-irradiating and painless technique. However there are two limitations to this technique: the lack of cooperation of some children and the still limited availability of high quality equipment in intensive care units. Indeed most of the applications described in this paper (ie. pyelonephritis, renovascular hypertension, tumors, acute renal insufficiency and renal vein thrombosis) require, besides an experienced operator, expensive power doppler equipment including high frequency and high resolution probes.  相似文献   
79.
Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow.  相似文献   
80.
Impaired gut barrier function has been reported in a wide range of diseases and syndromes and in some functional gastrointestinal disorders. In addition, there is increasing evidence that suggests the gut microbiota tightly regulates gut barrier function and recent studies demonstrate that probiotic bacteria can enhance barrier integrity. Here, we aimed to investigate the effects of Lactobacillus rhamnosus CNCM I-3690 on intestinal barrier function. In vitro results using a Caco-2 monolayer cells stimulated with TNF-α confirmed the anti-inflammatory nature of the strain CNCM I-3690 and pointed out a putative role for the protection of the epithelial function. Next, we tested the protective effects of L. rhamnosus CNCM I-3690 in a mouse model of increased colonic permeability. Most importantly, we compared its performance to that of the well-known beneficial human commensal bacterium Faecalibacterium prauznitzii A2-165. Increased colonic permeability was normalized by both strains to a similar degree. Modulation of apical tight junction proteins expression was then analyzed to decipher the mechanism underlying this effect. We showed that CNCM I-3690 partially restored the function of the intestinal barrier and increased the levels of tight junction proteins Occludin and E-cadherin. The results indicate L. rhamnosus CNCM I-3690 is as effective as the commensal anti-inflammatory bacterium F. prausnitzii to treat functional barrier abnormalities.  相似文献   
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