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91.
It is still unclear whether i.v. immunoglobulins (Ig) can facilitate the reproductive prognosis of women who have suffered recurrent pregnancy loss. We report the results of a multicentre placebo- controlled study on the effect of Ig administration on pregnancy outcome in 46 women who had suffered at least three recurrent miscarriages. All were screened to exclude chromosomal or Mullerian abnormalities, the presence of antinuclear antibodies, lupus anticoagulant (LA) or elevated titres of anticardiolipin antibodies which may have revealed an underlying autoimmune problem. To avoid a selection bias towards ongoing pregnancies, i.v. Ig or placebo were administered between weeks 5 and 7 of gestation for 2 consecutive days as soon as each woman knew she was pregnant and before embryonic heart activity could be detected. A further infusion was administered at week 8 when ultrasonography confirmed an ongoing embryonic development. In all, 68% of the women who received Ig went to term versus 79% of those who received a placebo (not significant), with no significant differences in the pregnancy course or the perinatal outcome. These results suggest either that women with recurrent miscarriages who have no recognized cause of pregnancy loss have a good reproductive prognosis without any treatment or that the emotional care associated with the administration of a placebo can indirectly facilitate the progression of pregnancy.   相似文献   
92.
The reported incidence of grades II to IV acute graft-versus-host disease (GVHD) after hematopoietic cell transplantation with HLA-identical sibling donors has increased considerably during the past 15 to 20 years at our center. The purpose of this study was to evaluate the potential reasons for this change. We reviewed organ stages and overall grades of GVHD for 2220 patients who received a first marrow or peripheral blood cell transplant from an HLA-identical sibling or an HLA-allele-matched unrelated donor with the use of a posttransplantation immunosuppressive regimen that included both methotrexate and cyclosporine between 1985 and 2001. The most striking change was an increased incidence of stage 1 gut involvement from 10% to 20% before 1992 to 50% to 60% since 1992, both with related and unrelated donors. This change increased the incidence of grade II GVHD with sibling donors, such that the overall incidence of grade II to IV GVHD is now 60% to 70%. Among patients with chronic myeloid leukemia in chronic phase, the increasingly frequent diagnosis of acute GVHD since 1992 has not been associated with decreased survival. A high diagnostic sensitivity and increased awareness that gut GVHD can occur without skin involvement account for the increased incidence of acute GVHD at our center.  相似文献   
93.
The development of tubal obstruction and subsequent infertility is a major sequelum of upper genital tract infection with Chlamydia trachomatis; however, little is known about the pathogenesis of the infection. In this investigation, the authors present a detailed study of the progression of ascending chlamydial infection in female guinea pigs resulting from intravaginal inoculation of the Chlamydia psittaci agent of guinea pig inclusion conjunctivitis (GPIC). Isolation of chlamydiae from different tissues of the genital tract revealed definitive evidence for ascending infection that was not dose-related. By 7 days after infection, GPIC was isolated from the endometrium and oviducts of 78% of the animals. Pathologic changes analogous to those seen in human chlamydial disease, including polymorphonuclear, mononuclear, and plasma cell infiltration, were seen in the endometrium and oviducts, although not all isolation positive animals developed overt tubal disease. Long-term fibrosis, often in combination with hydrosalpinx, was noted in the mesosalpingeal tissue in 20% of the animals. Thus, the guinea pig:GPIC system represents a model for ascending chlamydial infection resulting from vaginal inoculation of normal guinea pigs that closely approximates the disease as seen in humans and can be used to study the pathogenesis of chlamydial genital infection.  相似文献   
94.
Genetics of rheumatoid arthritis   总被引:4,自引:0,他引:4  
The haplotype sharing distribution in affected sib pairs are used to demonstrate the linkage of a susceptibility gene for rheumatoid arthritis (RA) to the HLA region. Family and population studies suggest heterogeneity in the etiology of RA.  相似文献   
95.
A randomized double-blind trial with a 7-valent pneumococcal conjugate vaccine was conducted in The Netherlands among 383 children, aged 1 to 7 years, with a history of recurrent acute otitis media. No effect of vaccination on the pneumococcal colonization rate was found. However, a shift in serotype distribution was clearly observed (R. Veenhoven et al., Lancet 361:2189-2195, 2003). We investigated the molecular epidemiology of 921 pneumococcal isolates retrieved from both the pneumococcal vaccine (PV) and control vaccine (CV) groups during the vaccination study. Within individuals a high turnover rate of pneumococcal restriction fragment end labeling genotypes, which was unaffected by vaccination, was observed. Comparison of the genetic structures before and after completion of the vaccination scheme revealed that, despite a shift in serotypes, there was clustering of 70% of the pneumococcal populations. The remaining isolates (30%) were equally observed in the PV and CV groups. In addition, the degree of genetic clustering was unaffected by vaccination. However, within the population genetic structure, nonvaccine serotype clusters with the serotypes 11, 15, and 23B became predominant over vaccine-type clusters after vaccination. Finally, overall pneumococcal resistance was low (14%), and, albeit not significant, a reduction in pneumococcal resistance as a result of pneumococcal vaccination was observed. Molecular surveillance of colonization in Dutch children shows no effect of pneumococcal conjugate vaccination on the degree of genetic clustering and the genetic structure of the pneumococcal population. However, within the genetic pneumococcal population structure, a clear shift toward nonvaccine serotype clusters was observed.  相似文献   
96.
The introduction of science into the practice of medicine in the early 20th century was a transforming event for the profession. Now, breakthroughs in science and know how make it possible to transform care once again and to fix the broken U.S. health care system. To realize this potential, new models of prospective health care must be created and validated. Prospective health care would determine the risk for individuals to develop specific diseases, detect the disease's earliest onset, and prevent or intervene early enough to provide maximum benefit. Each individual would have a personalized health plan to accomplish this. Current knowledge is already sufficient to implement this approach, but there are no effective practice models, delivery systems, and appropriate reimbursement mechanisms. The authors describe the mechanisms of managing care prospectively, describe the components of a personalized health plan, and show how prospective care could relate to a community or group of covered individuals. They conclude by stressing that all interested parties, including academic health centers, insurers, and payers, will need to work together to develop innovative applications of new technologies and appropriate delivery models. At their own institution, pilot programs to foster prospective health care have already begun, and another initiative to develop models to use genomic medicine is also underway. Bipartisan political support will also be needed to help achieve rational reimbursement between providers and payers, so that prospective care can fulfill its promise of being the best cost-effective model to improve the nation's health.  相似文献   
97.
Two prospective studies were undertaken to evaluate a commercial indirect fluorescent-antibody (IFA) stain for the detection of Pneumocystis carinii in respiratory specimens from individuals at risk for or with the acquired immunodeficiency syndrome. The first study compared IFA with Diff-Quik (DQ; a rapid Giemsa-like stain) for detecting P. carinii in 95 induced sputa obtained from 77 asymptomatic patients who had survived one previous episode of P. carinii pneumonia and who were being treated prophylactically with aerosolized pentamidine. Only one induced sputum specimen was found to contain P. carinii; organisms were detected by both stains. The second study compared the performance of the IFA stain versus DQ, modified toluidine blue O, and Gomori methenamine silver stains for detecting P. carinii in symptomatic individuals at risk for or with acquired immunodeficiency syndrome. Of 182 specimens examined, P. carinii was detected in 105 by one or more stains; the DQ stain detected 73 (70%), the modified toluidine blue O stain detected 75 (71%), the Gomori methenamine silver stain detected 76 (72%), and the IFA stain detected 95 (90%). The IFA stain was more sensitive (P less than 0.01) than the other traditional stains for detecting P. carinii; however, a subsequent clinical evaluation revealed that a subset of IFA-positive-only specimens were from patients whose clinical symptoms resolved without specific anti-P. carinii therapy.  相似文献   
98.
Taylor GM  Zullo AJ  Larson GM  Sanders DA 《Virology》2003,316(1):184-189
Retrovirus packaging cell lines that express the Moloney murine leukemia virus gag, pol, and env genes and a retroviral vector genome can produce virus particles that are capable of transducing cells. Normally if the packaging cell line does not produce a functional viral fusion glycoprotein, such as the retroviral envelope protein or a foreign viral glycoprotein, then the viruses will be incapable of transducing cells. We have found that incubating envelope protein-deficient virus particles bound to cells with chlorpromazine leads to transduction. Chlorpromazine (CPZ) is a membrane-active reagent that is commonly used to induce the hemifusion to fusion transition when membrane fusion is mediated by partially defective viral glycoproteins. The concentration and pH dependence of the promotion of transduction by CPZ is consistent with a role for CPZ micelle formation in viral entry. These data indicate that caution is warranted when experiments concerning membrane fusion completion promoted by CPZ are analyzed.  相似文献   
99.
The ileoanal J pouch: radiographic evaluation   总被引:1,自引:0,他引:1  
Hillard  AE; Mann  FA; Becker  JM; Nelson  JA 《Radiology》1985,155(3):591-594
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.  相似文献   
100.
We have reviewed the electromyographic (EMG) studies of 17 patients with chronic progressive external ophthalmoplegia (CPEO). In 13 of 17 patients, conventional concentric needle EMG demonstrated a "myopathic" pattern, usually predominating in the shoulder muscles. Single-fiber EMG showed increased jitter and/or blocking in at least one muscle in 13 of 16 patients. Jitter was increased in the frontalis muscle in 10 of 13 patients and in an arm muscle in 5 of 12. When both muscles were tested, jitter was greater in the frontalis muscle in 5 patients and in the arm muscle in 2. These observations demonstrate that it may be difficult to distinguish myasthenia gravis from CPEO by EMG. The frequency with which abnormal jitter is found in CPEO suggests that, in addition to a mild generalized myopathy, a primary defect in neuromuscular transmission may be present.  相似文献   
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