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351.
The authors describe 7 male patients from two unrelated families who presented with what appears to be a heretofore undiagnosed X-linked variant of Ehlers-Danlos syndrome. Unlike the eight previously reported types, this variant is manifested by specific skeletal abnormalities, including occipital exostoses, widening and bowing of multiple long bones at tendinous and ligamentous insertion sites, and deformed clavicles. Major clinical complications include genitourinary problems, chronic diarrhea with malabsorption, and/or syncopal episodes. Laboratory tests suggest that this variant may represent the true lysyl-oxidase-deficient form of Ehlers-Danlos syndrome.  相似文献   
352.
FTY720: altered lymphocyte traffic results in allograft protection   总被引:21,自引:0,他引:21  
  相似文献   
353.
Ecto-5'nucleotidase (5'NT) activity of peripheral blood (PB) lymphocytes was determined in 31 patients with serum monoclonal gammopathies (MG). Twenty-one patients had a diagnosis of multiple myeloma (MM), and ten patients had monoclonal gammopathy of undetermined significance (MGUS). The proliferative activity of the bone marrow plasma cells (LI%) was investigated in 28 of these MG patients by means of tritiated thymidine uptake evaluated by simultaneous autoradiography and cytoplasmic immunofluorescence. 5'NT activity was significantly lower in MG patients as compared with normal controls. MM patients had lower 5'NT activity than MGUS patients, but the difference was not significant. By contrast, MM had significantly higher LI% than MGUS patients. There was a linear regression of 5'NT on LI% which was statistically significant: the higher the LI%, the lower the 5'NT. Because the LI% is an accurate prognostic and monitoring factor in MG, this correlation indicates that 5'NT may be of assistance in predicting the clinical progress of MG patients. In seven MGs, the PB T and B lymphocytes were studied separately. The T cell subpopulation was 5'NT deficient compared to the normal controls, shown as a significant linear regression of T cell 5'NT on the LI%. This suggests that in MG there may be an alteration of nonneoplastic T lymphocytes correlated with tumor growth. The OKT8+ lymphocytes were mainly responsible for the 5'NT deficiency of unseparated T lymphocytes.  相似文献   
354.
Objective: To evaluate the relationship between maternal serum α-fetoprotein (MSAFP) and the risk of persistent placenta previa.

Methods: We conducted a retrospective cohort study of singleton pregnancies with sonographic evidence of placenta previa at 15?–?20 weeks' gestation, between October 1991 and August 2000. Only pregnancies with MSAFP determination at 15?–?20 weeks' gestation and non-anomalous live-born infants ??24 weeks' gestation were included. Pregnancies in which Cesarean delivery was performed for placenta previa were considered persistent; this was the primary outcome.

Results: Of 275 women with previa at 15?–?20 weeks' gestation, 33 (12%) had previa at delivery. Trend analysis revealed a greater likelihood of persistent previa with increasing MSAFP values (p?=?0.01). Mid-trimester MSAFP <?1 multiple of the median (MoM) was associated with a decreased incidence of persistence of 4%, significantly less than the risk at ??1 MoM (16%; p?=?0.01).

Conclusions: There is an association between increasing MSAFP values and greater likelihood of persistent placenta previa. An MSAFP value <?1 MoM is associated with a reduction in the risk of persistence of previa to delivery.  相似文献   
355.

BACKGROUND:

The validity of surveillance systems has rarely been a topic of investigation.

OBJECTIVE:

To assess potential biases that may influence the validity of contemporary antimicrobial-resistant (AMR) pathogen surveillance systems.

METHODS:

In 2008, reports of laboratory-based AMR surveillance systems were identified by searching Medline. Surveillance systems were appraised for six different types of bias. Scores were assigned as ‘2’ (good), ‘1’ (fair) and ‘0’ (poor) for each bias.

RESULTS:

A total of 22 surveillance systems were included. All studies used appropriate denominator data and case definitions (score of 2). Most (n=18) studies adequately protected against case ascertainment bias (score = 2), with three studies and one study scoring 1 and 0, respectively. Only four studies were deemed to be free of significant sampling bias (score = 2), with 17 studies classified as fair, and one as poor. Eight studies had explicitly removed duplicates (score = 2). Seven studies removed duplicates, but lacked adequate definitions (score = 1). Seven studies did not report duplicate removal (score = 0). Eighteen of the studies were considered to have good laboratory methodology, three had some concerns (score = 1), and one was considered to be poor (score = 0).

CONCLUSION:

Contemporary AMR surveillance systems commonly have methodological limitations with respect to sampling and multiple counting and, to a lesser degree, case ascertainment and laboratory practices. The potential for bias should be considered in the interpretation of surveillance data.  相似文献   
356.

Background

Immigrants to Germany and their children are at particular risk for tuberculosis (TB).

Methods

35 Patients (10 male/25 female aged 2 - 59 years (median 33 years) originating mostly from high incidence countries in Asia (19 [54.3%]) in Africa (14 [40.0%] and East Europe (2 [5.7%]), attended at the Tropical Medicine unit were analysed.

Results

Primary clinical presentation was most frequently lymphadenitis (13 [37.1%]). other organs involved included bones (7 [20.0%]), central nervous system (5 [14.3%]), urogenital organs (3 [8.6%]), lung (3 [8.6%]), mediastinum, (2 [5.7%]) and abdomen (2 [5.7%]). ESR was abnormal in 21/28 (75.0%), CRP in 20/35 (57.1%), and protein electrophoresis in 22/26 (84.6%) cases. The tuberculin skin test was strongly positive in all 15 cases where the test had been performed. Tuberculosis interferon gamma release assay (TB-IGRA) was positive in all 35 cases (100%). PCR for nucleic acids of Mycobacterium (M.) tuberculosis complex was positive in only 7/20 (35.0%) cases. M. tuberculosis was identified in 32/35 (91.4%), M. bovis in 2 (5.7%) cases. 1 case was diagnosed clinically. All patients were negative for HIV. Typical histopathology was seen in the 29 cases, where biopsies had been taken. Chest-X-ray did not reveal specific pulmonary lesions in the majority of cases (22/35 [62.9%]). Diagnosis of TB was mostly delayed (4 to 299 weeks, [median 8]). The most frequent primary suspicion was a malignancy (17/35 [48.6%]) while TB was initially suspected in 5 cases only. Diagnosis of TB is impeded by its multifaceted presentation especially in immigrants.  相似文献   
357.
某部新兵入伍前自杀未遂的心理社会危险因素研究   总被引:1,自引:0,他引:1  
1 对象和方法 1.1 对象 采取多级整群抽样法,随机抽取某部新兵996名 (均为男性)作为调查对象,因执行任务而请假者10人,在收 回的986份有效问卷中,年龄16~22[平均(18.3±1.5)]岁; 高中及高中以上者845人,初中及初中以下者141人. 1.2 方法 调查内容有自编调查问卷、父母教养方式问卷[1] (EMBU)、青少年生活事件量表[2](ASLEC)和艾森克个性问 卷(EPQ).调查时先讲明目的,并要求独立完成;对不合作者尽 量说服鼓励其完成问卷,以尽量减少无应答所造成的偏倚.再 对初筛出的自杀未遂者进行逐个调查,确定自杀未遂的诊断及 自杀原因、方式、…  相似文献   
358.
359.
Previous studies that used peptide-MHC (pMHC) tetramers (tet) to identify self-specific T cells have questioned the effectiveness of thymic-negative selection. Here, we used pMHCI tet to enumerate CD8 T cells specific for the immunodominant gp33 epitope of lymphocytic choriomeningitis virus glycoprotein (GP) in mice transgenically engineered to express high levels of GP as a self-antigen in the thymus. In GP-transgenic mice (GP+), monoclonal P14 TCR+ CD8 T cells that express a GP-specific TCR could not be detected by gp33/Db-tet staining, indicative of their complete intrathymic deletion. By contrast, in the same GP+ mice, substantial numbers of polyclonal CD8 T cells identifiable by gp33/Db-tet were present. The gp33-tet staining profiles of polyclonal T cells from GP+ and GP-negative (GP) mice were overlapping, but mean fluorescence intensities were ∼15% lower in cells from GP+ mice. Remarkably, the gp33-tet+ T cells in GP+ mice failed to clonally expand after lymphocytic choriomeningitis virus infection, whereas those of GP mice did so. In Nur77GFP-reporter mice, dose-dependent responses to gp33 peptide-induced TCR stimulation revealed that gp33-tet+ T cells with high ligand sensitivity are lacking in GP+ mice. Hence, pMHCI tet staining identifies self-specific CD8 T cells but tends to overestimate the number of truly self-reactive cells.  相似文献   
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