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61.
Antiphospholipid antibodies--our experience   总被引:1,自引:0,他引:1  
Antiphospholipid antibodies (APA) have aroused multispeciality interests. In our study of 200 cases worked up for APA, we have used a few simple coagulation tests to detect lupus anticoagulant (LA) and ELISA to detect anticardiolipin antibodies. The positivity rate for LA among cases with recurrent pregnancy loss was 4.16% and for aCL 20.8%. The positivity rate for LA in patients with venous thrombosis was 6.2%, in arterial thrombosis was 7.14% and in SLE patients was 58.3%. In conclusion APAs are to be looked for in cases of recurrent pregnancy loss, thrombosis in people < 45 years of age without risk factors and SLE patients to assess the thrombotic risk and to decide on anti coagulant therapy for further management.  相似文献   
62.
The heat shock protein (HSP) response of Salmonella typhi following exposure to elevated growth temperatures was studied. Three major proteins with molecular sizes of 58, 68, and 88 kDa were abundantly expressed when S. typhi cells were shifted from 37 to 45 degrees C and to 55 degrees C. These proteins were also constitutively expressed at 37 degrees C. Western blotting and immunoprecipitation studies with anti-HSP monoclonal antibodies revealed that the 58- and 68-kDa proteins were analogous to the GroEL and DnaK proteins, respectively, of Escherichia coli. These HSPs are also abundantly present in the outer membrane fraction of disrupted cells and, to a lesser extent, in the cytosol. Immunoblotting experiments with sera from patients with a culture-positive diagnosis of typhoid fever showed the presence of antibodies to these HSPs. Nine of twelve sera reacted with the 58-, 68-, and 88-kDa proteins, while three sera reacted only with the 68- and 88-kDa proteins. All 10 sera from healthy individuals showed no binding to these HSPs. In light of the well-documented roles of HSPs in the pathogenesis of microbial infections and as immunodominant antigens, these findings may be relevant for a better understanding of disease processes and for the future development of diagnostic and preventive strategies.  相似文献   
63.
Epithelial–mesenchymal interactions are key to skin morphogenesis and homeostasis. We report that maintenance of the hair follicle keratinocyte cell fate is defective in mice with mesenchymal deletion of the CSL/RBP-Jκ gene, the effector of “canonical” Notch signaling. Hair follicle reconstitution assays demonstrate that this can be attributed to an intrinsic defect of dermal papilla cells. Similar consequences on hair follicle differentiation result from deletion of Wnt5a, a specific dermal papilla signature gene that we found to be under direct Notch/CSL control in these cells. Functional rescue experiments establish Wnt5a as an essential downstream mediator of Notch–CSL signaling, impinging on expression in the keratinocyte compartment of FoxN1, a gene with a key hair follicle regulatory function. Thus, Notch/CSL signaling plays a unique function in control of hair follicle differentiation by the underlying mesenchyme, with Wnt5a signaling and FoxN1 as mediators.  相似文献   
64.
The use of the polymerase chain reaction (PCR) in molecular diagnosis is now accepted worldwide and has become an essential tool in the research laboratory. In the laboratory, a rapid detection, serotyping and quantitation, one-step real-time RT-PCR assay was developed for dengue virus using TaqMan probes. In this assay, a set of forward and reverse primers were designed targeting the serotype conserved region at the NS5 gene, at the same time flanking a variable region for all four serotypes which were used to design the serotype-specific TaqMan probes. This multiplex one-step RT-PCR assay was evaluated using 376 samples collected during the year 2003. These groups included RNA from prototype dengue virus (1-4), RNA from acute serum from which dengue virus was isolated, RNA from tissue culture supernatants of dengue virus isolated, RNA from seronegative acute samples (which were culture and IgM negative) and RNA from samples of dengue IgM positive sera. The specificity of this assay was also evaluated using a panel of sera which were positive for other common tropical disease agents including herpes simplex virus, cytomegalovirus, measles virus, varicella-zoster virus, rubella virus, mumps virus, WWF, West Nile virus, Japanese encephalitis virus, S. typhi, Legionella, Leptospira, Chlamydia, and Mycoplasma. The sensitivity, specificity and real-time PCR efficiency of this assay were 89.54%, 100% and 91.5%, respectively.  相似文献   
65.

Introduction

The histological changes during the development of the human uterus throughout the fetal period exhibit varying cellular patterns in the lining epithelium. The present study documents these progressive changes during fetal uterine maturation.

Methods

70 fetal uteri whose age varies from 14th to 40th gestational weeks without any external anomalies were studied.

Results

At 14 weeks, the uterine lining epithelium is predominantly pseudostratified columnar, the nuclei being arranged at varying levels. However, the lower part of cervix shows epithelium comprising of a mosaic of flat or slightly raised polygonal cells which gradually changes to stratified squamous epithelium with advancing gestation. From 32 weeks onwards, the pseudostratification of uterine epithelium changes to simple columnar epithelium progressively. At 14 weeks, two distinct layers of mesenchymal cells are apparent, elongated cells in abundance at the subserosal layer and sparsely arranged rounded cells towards the lumen. Endometrial glands appear by the 17th week.

Discussion

Except for the lower part of cervix, pseudostratified columnar epithelium lines the fetal uterus. As gestation progresses, pseudostratification gradually changes to simple columnar epithelium. The palmate folds of the epithelium appear by 17 weeks in cervical canal. The smooth muscle bundle appears by 24 weeks of gestation. Undifferentiated mesenchymal cells around paramesonephric duct develop into both smooth muscles and endometrial cells.  相似文献   
66.

Background

Angina affects more than 50 million people worldwide. Secondary prevention interventions such as cardiac rehabilitation are not widely available for this population. An Internet-based version could offer a feasible alternative.

Objective

Our aim was to examine the effectiveness of a Web-based cardiac rehabilitation program for those with angina.

Methods

We conducted a randomized controlled trial, recruiting those diagnosed with angina from general practitioners (GPs) in primary care to an intervention or control group. Intervention group participants were offered a 6-week Web-based rehabilitation program (“ActivateYourHeart”). The program was introduced during a face-to-face appointment and then delivered via the Internet (no further face-to-face contact). The program contained information about the secondary prevention of coronary heart disease (CHD) and set each user goals around physical activity, diet, managing emotions, and smoking. Performance against goals was reviewed throughout the program and goals were then reset/modified. Participants completed an online exercise diary and communicated with rehabilitation specialists through an email link/synchronized chat room. Participants in the control group continued with GP treatment as usual, which consisted of being placed on a CHD register and attending an annual review. Outcomes were measured at 6-week and 6-month follow-ups during face-to-face assessments. The primary outcome measure was change in daily steps at 6 weeks, measured using an accelerometer. Secondary outcome measures were energy expenditure (EE), duration of sedentary activity (DSA), duration of moderate activity (DMA), weight, diastolic/systolic blood pressure, and body fat percentage. Self-assessed questionnaire outcomes included fat/fiber intake, anxiety/depression, self-efficacy, and quality of life (QOL).

Results

A total of 94 participants were recruited and randomized to the intervention (n=48) or the usual care (n=46) group; 84 and 73 participants completed the 6-week and 6-month follow-ups, respectively. The mean number of log-ins to the program was 18.68 (SD 13.13, range 1-51), an average of 3 log-ins per week per participant. Change in daily steps walked at the 6-week follow-up was +497 (SD 2171) in the intervention group and –861 (SD 2534) in the control group (95% CI 263-2451, P=.02). Significant intervention effects were observed at the 6-week follow-up in EE (+43.94 kcal, 95% CI 43.93-309.98, P=.01), DSA (–7.79 minutes, 95% CI –55.01 to –7.01, P=.01), DMA (+6.31 minutes, 95% CI 6.01-51.20, P=.01), weight (–0.56 kg, 95% CI –1.78 to –0.15, P=.02), self-efficacy (95% CI 0.30-4.79, P=.03), emotional QOL score (95% CI 0.01-0.54, P=.04), and angina frequency (95% CI 8.57-35.05, P=.002). Significant benefits in angina frequency (95% CI 1.89-29.41, P=.02) and social QOL score (95% CI 0.05-0.54, P=.02) were also observed at the 6-month follow-up.

Conclusions

An Internet-based secondary prevention intervention could be offered to those with angina. A larger pragmatic trial is required to provide definitive evidence of effectiveness and cost-effectiveness.

Trial Registration

International Standard Randomized Controlled Trial Number (ISRCTN): 90110503; http://www.controlled-trials.com/ISRCTN90110503/ISRCTN90110503 (Archived by WebCite at http://www.webcitation.org/6RYVOQFKM).  相似文献   
67.
This study investigated the effect of 10 or 100 mg/kg/day quercetin on the uterus of ovariectomized adult female rats receiving sex-steroid replacement regime mimicking changes in hormonal profiles during the reproductive cycle. Following seven days of treatment with estrogen and progesterone with or without quercetin, uteri were harvested for histological and proliferative cell nuclear antigen (PCNA) protein and mRNA expression and PCNA protein distribution analyses. Our findings indicated that co-administration of 10 mg/kg/day quercetin with estrogen and progesterone caused a significant decrease in the size of uterine lumen and epithelial heights with lower PCNA protein and mRNA expression as compared to estrogen plus progesterone-only treatment (P < 0.05). Concomitant treatment with estrogen and progesterone with 100 mg/kg/day quercetin resulted in a marked increase in the number of glands with increased PCNA protein and mRNA expression. Significantly higher PCNA distribution was observed in the stroma and glands as compared to estrogen plus progesterone-only treatment (P < 0.05). In conclusion, at 10 mg/kg/day, quercetin affects uterine morphology but not proliferation, however at 100 mg/kg/day, quercetin induced significant stromal and glandular proliferation which could predispose the uterus towards neoplastic development.  相似文献   
68.
A standardized serum bactericidal assay (SBA) is required to evaluate the functional activity of antibody produced in response to Neisseria meningitidis serogroup A and C vaccines. We evaluated assay parameters (assay buffer, target strains, growth of target cells, target cell number, complement source and concentration, and methods for growth of surviving bacteria) which may affect the reproducibility of SBA titers. The various assay parameters and specificity of anticapsular antibody to five serogroup A strains (A1, ATCC 13077, F8238, F9205, and F7485) and four serogroup C strains (C11, G7880, G8050, and 1002-90) were evaluated with Centers for Disease Control and Prevention meningococcal quality control sera. The critical assay parameters for the reproducible measurement of SBA titers were found to include the target strain, assay incubation time, and complement. The resulting standardized SBA was used by 10 laboratories to measure functional anticapsular antibody against serogroup A strains F8238 and serogroup C strain C11. In the multilaboratory study, SBA titers were measured in duplicate for 14 pairs of sera (seven adults and seven children) before and after immunization with a quadrivalent polysaccharide (A, C, Y, and W-135) vaccine. The standardized SBA was reliable in all laboratories regardless of experience in performing SBAs. For most sera, intralaboratory reproducibility was +/- 1 dilution; interlaboratory reproducibility was +/- 2 dilutions. The correlation between median titers (interlaboratory) and enzyme-linked immunosorbent assay total antibody concentrations was high for both serogroup A (r = 0.86; P < 0.001; slope = 0.5) and serogroup C (n = 0.86; P < 0.001; slope = 0.7). The specified assay, which includes the critical parameters of target strain, incubation time, and complement source, will facilitate interlaboratory comparisons of the functional antibody produced in response to current or developing serogroup A and C meningococcal vaccines.  相似文献   
69.
We reported the first use of group B meningococcal conjugate vaccines in a nonhuman primate model (S. J. N. Devi, C. E. Frasch, W. Zollinger, and P. J. Snoy, p. 427-429, in J. S. Evans, S. E. Yost, M. C. J. Maiden, and I. M. Feavers, ed., Proceedings of the Ninth International Pathogenic Neisseria Conference, 1994). Three different group B Neisseria meningitidis capsular polysaccharide (B PS)-protein conjugate vaccines and an Escherichia coli K92 capsular polysaccharide-tetanus toxoid (K92-TT) conjugate vaccine are here evaluated for safety and relative immunogenicities in juvenile rhesus monkeys with or without adjuvants. Monkeys were immunized intramuscularly with either B PS-cross-reactive material 197 conjugate, B PS-outer membrane vesicle (B-OMV) conjugate, or N-propionylated B PS-outer membrane protein 3 (N-pr. B-OMP3) conjugate vaccine with or without adjuvants at weeks 0, 6, and 14. A control group of monkeys received one injection of the purified B PS alone, and another group received three injections of B PS noncovalently complexed with OMV. Antibody responses as measured by enzyme-linked immunosorbent assay varied among individual monkeys. All vaccines except B PS and the K92-TT conjugate elicited a twofold or greater increase in total B PS antibodies after one immunization. All vaccines, including the K92-TT conjugate, elicited a rise in geometric mean B PS antibody levels of ninefold or more over the preimmune levels following the third immunization. Antibodies elicited by N-pr. B-OMP3 and B-OMV conjugates were directed to the N-propionylated or to the spacer-containing B PS antigens as well as to the native B PS complexed with methylated human serum albumin. None of the vaccines caused discernible safety-related symptoms.  相似文献   
70.

Aim:

The aim of this study was to evaluate the effect of disfigurement due to cancer and its treatments on quality of life.

Materials and Methods:

A total of 120 patients from the inpatient/outpatient department of oncology who had undergone various forms of treatment for cancer were included in this study. The WHOQuality of Life BREF (WHOQL-BREF) version was administered to the patients to assess their quality of life.

Results:

Patients’ overall quality of life score ranged from 34 to 79 with an average of 53.18 (SD 11.94) and a large number of patients had scored from 40 to 54 on the WHOQOL-BREF.The study showed a significant difference between gender groups (t = 3.899, P < 0.05), with a significant difference in the mean quality of life between different categories of the prominent stigma (f = 4.018, P < 0.05) and the nature of stigma. Disfigurement clearly was a stressful experience for both sexes, but substantially more distressing for women. Majority of the patients experienced poor quality of life in all dimensions, namely, physical health, psychological health, social relationships, environmental health, and other sociodemographic variables.

Conclusion:

Living with a disfiguring body which is visibly different is not always easy. A sudden change either due to cancer or its treatment or due to side effects leads to significant social maladjustment, elevated anxiety, depression, and poor quality of life among the cancer survivors with body disfigurement which calls for multiprofessional involvement in addressing various psychosocial issues.  相似文献   
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