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31.
In-vitro fertilization patients (n = 15) at risk of ovarian hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day of human chorionic gonadotrophin administration and 25 or more follicles of intermediate or large size) underwent aspiration of all follicles and cryopreservation of all fertilized oocytes at the pronuclear stage. Patients were monitored for up to 2 weeks post- retrieval. Subsequent transfer of cryopreserved-thawed embryos was performed in programmed cycles using exogenous oestrogen and progesterone for endometrial preparation. Two patients (13%) developed OHSS necessitating hospitalization and vaginal aspiration of ascitic fluid. Two other patients (13%) developed moderate OHSS requiring ascitic fluid vaginal aspiration in the office setting, with dramatic improvement of the condition. Subsequent transfer of cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per transfer and ongoing or delivery rates of 42 and 67% per transfer and per patient respectively. By eliminating pregnancy potential with cryopreservation of all prezygotes and examining the pregnancy potential with subsequent cryopreserved-thawed transfers, it is concluded that OHSS is reduced, but not eliminated for patients at risk. Subsequent transfer of cryopreserved-thawed prezygotes in a programmed cycle with exogenous steroids yields an excellent pregnancy rate.   相似文献   
32.
The aim of this study was to compare the efficacy of pure follicle stimulating hormone (FSH) with that of FSH/human menopausal gonadotrophin (HMG) combination in downregulated cycles. A total of 357 patients was evaluated retrospectively. Sixty percent of patients in the FSH group and 55% in the FSH/HMG group were new; the others were repeat patients. Ovulation was suppressed with leuprolide acetate in all patients, followed by either FSH (n = 218) or FSH/HMG (n = 119). There was no difference in patients' age, infertility factors, number of ampoules used, length of stimulation, oestradiol levels on day of human chorionic gonadotrophin (HCG) administration, number of oocytes recovered or the number of embryos transferred. Also, nuclear maturity at aspiration and fertilization rates were not different between the two groups. FSH stimulation resulted in a significantly higher percentage of mature oocytes that showed the typical 'mature' morphological characteristics (P < 0.0001). The clinical pregnancy rates per transfer were 40 and 28% in patients stimulated with pure FSH and FSH/HMG respectively (P < 0.05). The significantly higher number of immature oocytes matured in vitro in the FSH/HMG group (P = 0.001) suggests a possible effect on in-vitro maturation, due to luteinizing hormone present in HMG. The difference in mature oocyte quality may be an important determinant in the higher pregnancy rates for the FSH- stimulated patients.   相似文献   
33.
This communication deals with the question of which of the viral antigens constitutes the targets for cytotoxic T lymphocytes (CTL) generated against herpes simplex virus type 1 (HSV-1). The approach used was, first, to compare cytotoxicity of CTL against target cells infected with virus in the presence of tunicamycin and 2-deoxy-D-glucose, which are known to inhibit glycoprotein synthesis, and second, to compare cytotoxicity of CTL against target cells infected with wild-type HSV-1 with that against target cells infected with a temperature-sensitive mutant of HSV-1 which, at the nonpermissive temperature, exhibits diminished glycoprotein synthesis. The results show that glycoprotein expression is required for the demonstration of cytotoxic activity of CTL. The level of cytotoxicity against the temperature-sensitive HSV-1 target at the nonpermissive temperature was reduced and correlated with the level of expression of the major envelope glycoprotein region (VP123; molecular weight = 123,000) at the target cell surface as measured serologically by antibody binding studies. The results were interpreted to indicate that HSV-1-induced glycoproteins are the target antigens for anti-HSV CTL and that the principal viral antigens recognized by the CTL may be glycoproteins of the VP123 region.  相似文献   
34.

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   
35.
In this prospective study, the use of a culture-enhanced PCR assay for the detection of Mycoplasma pneumoniae, followed by hybridization with a specific probe (MP-HPCR) or without hybridization (MP-PCR), and the use of a nested PCR (MP-NPCR) were evaluated. Clinical samples (190 specimens) from 190 patients with respiratory complaints were incubated in culture broth overnight and then subjected to PCR. The results of the PCR were compared to those obtained by culture, the direct antigen test, and serologic testing by microparticle agglutination and by immunoblotting in unclear cases. The sensitivities were 19 CFU for MP-PCR, 1.9 CFU for MP-HPCR, and 0.019 CFU for MP-NPCR. PCR amplification of the β-globin gene was possible in 98% of cases: after dilution of the β-globin-negative samples, all samples were reactive. Correlation between negative MP-NPCR results and negative serology results was found in 89% of cases; a positive correlation was found with 10% of the patients. Samples from three immunocompromised patients were MP-NPCR positive but serologically negative. High respiratory colonization by M. pneumoniae (>105 CFU/ml) in patients with acute respiratory disease could be detected by culture, MP-PCR, and MP-NPCR. These results indicate that MP-PCR and MP-NPCR are reliable methods for the detection of M. pneumoniae in respiratory tract samples of patients with respiratory complaints.  相似文献   
36.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
37.
The incidence and severity of somatic symptoms were determined in 132 patients with major depressive disorder and 80 normal controls. The role of somatic symptoms was analyzed in relation to the unipolar-bipolar division, Research Diagnostic Criteria (RDC) subtypes, hypersomnia, and appetite increase. The data suggest that the rate and level of somatic symptoms increased with the severity of depression and age, only appetite loss differentiated unipolar from bipolar patients, and the classic somatic symptoms of depression were present in most RDC subtypes and not exclusively associated with the "endogenous" subtype. Hypersomnia or increased appetite identified two overlapping depressive subgroups; patients in both groups were young and characterized by high interpersonal sensitivity. Hypersomniac depressed patients were less anxious and agitated; patients with increased appetite were more hostile and showed a greater decrease in libido than age-matched and sex-matched patients with neither symptom.  相似文献   
38.
Early gastric cancer.   总被引:1,自引:0,他引:1       下载免费PDF全文
Although common in Japan, early gastric cancer (EGC = gastric adenocarcinoma confined to the mucosa and submucosa of the stomach, with or without regional lymph node metastases) is thought to be an infrequent occurrence in the United States. However, a review of all "curative" resections for carcinoma of the gastric body and antrum at the University of Virginia between 1974 and 1982 revealed EGC in five of 31 patients (16%). The purpose of the present study was to compare EGC to more advanced gastric cancer (ADV; n = 26) to determine whether any presenting historical, laboratory, x-ray, or endoscopic features distinguished the two groups before surgery and to ascertain whether postoperative survival in the United States mimicked the Japanese experience. All surviving patients were contacted, all charts were abstracted, all pathologic specimens were reexamined, and all radiographs were reviewed blindly by an experienced radiologist. Statistical evaluation was accomplished using Kaplan-Meier plots, chi square analysis, and unpaired "t" tests, as appropriate. At presentation, patients with EGC were younger (44 +/- 6 vs. 67 +/- 2 years, p less than 0.01) with higher admission albumin levels (4.1 +/- 0.2 vs. 3.7 +/- 0.1 mgm/dl, p less than 0.01). Although not significantly different, admission hemoglobin tended to be higher (41 +/- 2 vs. 35 +/- 2%), the incidence of weight loss tended to be less (40 vs. 65%), duration of symptoms tended to be longer (21 +/- 11 vs. 8 +/- 3 months), and tumor diameter tended to be smaller (1.7 +/- 0.6 vs. 5.8 +/- 0.7 cm) in EGC. No differences were apparent with respect to endoscopic or radiographic appearance, tumor location (greater than 70% antrum), presence of regional lymph node metastases (EGC = 2/5; ADV = 20/26), or type of resection (subtotal gastrectomy in 4/5 EGC, in 19/26 ADV). On median 5-year follow-up, however, survival with EGC has been 100%. In contrast, the Kaplan-Meier estimate of 5-year survival in ADV is 15% (42% with muscularis invasion, 0% with serosal invasion, 12% with extra-gastric spread; p less than 0.01 vs. EGC). One suture line recurrence in EGC was successfully treated by re-resection. No ADV patient with recurrence survives (p less than 0.01). Thus, EGC behaves similarly in the United States and Japan; for example, prognosis is excellent even in the presence of lymph node metastases. Inability to distinguish EGC from ADV before surgery justifies an aggressive surgical approach to all patients with resectable gastric neoplasms.  相似文献   
39.
Although interest in the role of donor-specific antibodies (DSAs) in kidney transplant rejection, graft survival, and histopathological outcomes is increasing, their impact on steroid avoidance or minimization in renal transplant populations is poorly understood. Primary outcomes of graft survival, rejection, and histopathological findings were assessed in 188 patients who received transplants between 2012 and 2015 at the Scripps Center for Organ Transplantation, which follows a steroid avoidance protocol. Analyses were performed using data from the United Network for Organ Sharing. Cohorts included kidney transplant recipients with de novo DSAs (dnDSAs; n = 27), preformed DSAs (pfDSAs; n = 15), and no DSAs (nDSAs; n = 146). Median time to dnDSA development (classes I and II) was shorter (102 days) than in previous studies. Rejection of any type was associated with DSAs to class I HLA (P < .05) and class II HLA (P < .01) but not with graft loss. Although mean fluorescence intensity (MFI) independently showed no association with rejection, an MFI >5000 showed a trend toward more antibody-mediated rejection (P < .06), though graft loss was not independently associated. Banff chronic allograft nephropathy scores and a modified chronic injury score were increased in the dnDSA cohort at 6 months, but not at 2 years (P < .001 and P < .08, respectively). Our data suggest that dnDSAs and pfDSAs impact short-term rejection rates but do not negatively impact graft survival or histopathological outcomes at 2 years. Periodic protocol post-transplant DSA monitoring may preemptively identify patients who develop dnDSAs who are at a higher risk for rejection.  相似文献   
40.
止泻散敷脐治疗婴幼儿腹泻100例   总被引:1,自引:1,他引:0  
梁蜀筠  刘延英 《医学争鸣》2000,21(12):1500-1500
0 引言 腹泻乃小儿最常见病 ,尤以 2岁以下婴幼儿最为常见 .年龄越小 ,发病率越高 ,且多在夏、秋季发病 .小儿患病后惧怕打针 ,服药以及输液 ,给治疗带来一些困难 . 12 a来 ,我们用自拟的止泻散敷脐治疗婴幼儿泄泻 ,效果良好 .1 对象和方法1.1 对象  1998- 0 6 / 1999- 10婴幼儿腹泻发病高峰期门诊病例 10 0 (男 6 6 ,女 34 )例 ,年龄 2月龄~ 5岁 .肠炎 5 8例 ,单纯消化不良 42例 . 6 7例曾多次治疗 ,33例初诊 .凡接受治疗之患儿 ,一律停止用其他药物 .1.2 方法 药物组成 :川椒 12 g,干姜 12 g,小茴香 12 g,白芷 2 0 g,吴茱萸 5 g,…  相似文献   
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