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121.
Trichomonas vaginalis causes a common genitourinary infection which is frequently asymptomatic. At present, pregnant women are not usually screened for the infection unless they are symptomatic. In the present study, we screened and obtained samples for culture from all pregnant women attending a prenatal clinic with the InPouch TV culture system and compared results with those of standard culture in Diamond's medium and slide wet mount examination. The InPouch TV culture system was as reliable as Diamond's medium in detecting T. vaginalis and may be useful and effective in a pregnancy clinic setting.  相似文献   
122.
Fifty-seven schizophrenic patients were initially assessed after admission to hospital, at which time their parents completed a Camberwell Family Interview, generating "expressed emotion" (EE) scores. Relapse over the next nine months was not predicted by household EE status or by individual EE scales. Multivariate analyses suggested that a poor course after hospitalization was best predicted by a poor course before admission and by living in a one-parent household. High household EE status was a predictor only in one multivariate analysis after course of illness and one-parent household status had been entered, suggesting an interaction effect. We query the causal proposition linking high EE and relapse and suggest instead that a poor illness course may elicit high EE in relatives, particularly in one-parent households, and, thus, may make the principal contribution to the proposed link.  相似文献   
123.
Recently, 2-halogenated deoxyadenosine analogs (F, Cl, and Br) have been shown to have antitumor activity. These analogs are phosphorylated by cells and are believed to exert their cytotoxic action at the nucleoside triphosphate level. In this work the interaction of these nucleoside triphosphate analogs with potential targets, such as DNA polymerase alpha, beta, and gamma, DNA primase, and ribonucleotide reductase was examined in detail. All of these compounds competitively inhibited the incorporation of dAMP into DNA by DNA polymerase alpha, beta, or gamma. F-dATP was able to completely substitute for dATP using DNA polymerase alpha and gamma, but not with DNA polymerase beta. Cl-dATP and Br-dATP substituted poorly for dATP using DNA polymerase alpha and beta. Extension of a 32P-labeled primer by DNA polymerase alpha, beta, or gamma on a single-stranded M13 template showed that these compounds were incorporated into the 3' end of the growing DNA chain and that elongation beyond the incorporated analogs was significantly retarded for Cl-dATP and Br-dATP using either DNA polymerase alpha or beta. DNA primase using poly(dC) as template was inhibited by these compounds at a concentration 4 to 5 times greater than that required for 2-F-araATP. The 2-halogenated dATP analogs were potent inhibitors of ADP reduction by ribonucleotide reductase. In conclusion, the cytotoxic action of 2-Cl-deoxyadenosine and 2-Br-deoxyadenosine may partially be mediated through the mechanism of "self-potentiation," by depression of the deoxynucleoside triphosphate pools due to inhibition of ribonucleotide reductase, which would facilitate their incorporation into DNA and result in the inhibition of DNA synthesis.  相似文献   
124.
The phosphoinositide signaling pathway, which mediates neurotransmitter responses, was studied in Xenopus oocytes by recording membrane currents evoked using lightflash photolysis of caged inositol trisphosphate (caged IP3) to produce rapid and reproducible transients in intracellular IP3 levels. Photolysis of caged IP3 evoked currents which were carried largely by chloride ions and depended upon intracellular, but not extracellular, calcium. A given light flash evoked larger responses when the amount of caged IP3 loaded into the oocyte was increased, and illumination of the vegetal hemisphere gave larger responses than the animal. Long (10 sec) light exposures produced oscillatory currents, resembling responses to serotonin and other agonists, which became larger, more transient, and of shorter latency as the light intensity was increased. Brief (ca. 100 msec) flashes evoked a single "spike" of current. The caged IP3 response showed a threshold, in that light flashes had to be greater than a certain intensity and duration before currents could be detected. Associated with this, sub- and suprathreshold light flashes caused a long-lasting (seconds or minutes) potentiation of responses to subsequent test flashes. The lightflash response was also potentiated by a preceding intracellular injection of IP3 and by extracellular application of an agonist thought to induce IP3 liberation. However, intracellular injections of calcium depressed the response. We conclude that the liberation of calcium from intracellular stores varies nonlinearly with the intracellular level of IP3. This phenomenon may explain earlier observations, including the long latency of currents evoked by low doses of agonists such as acetylcholine and serotonin, and the nonlinear facilitation seen between these agonists. Further, it suggests a mechanism for "chemical integration," which may be important in the functioning of neurons and other cells which use IP3 as an intracellular messenger.  相似文献   
125.
Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
126.
Measurement of human serum molecules with two-site ELISA can be biased by the presence of human heterophilic anti-animal immunoglobulin antibodies (HAIA) that cause false-positive signals by cross-linking the monoclonal (mAb) and/or polyclonal antibodies (pAb) used for the pre- (capture) and post-analyte steps (detection). To evaluate a novel ELISA format designed to avoid interference by HAIA, a target-specific non-immunoglobulin (Ig) affinity protein (affibody) was used to replace one of the antibodies. First, a human IgA-binding affibody (Z(IgA)) selected by phage display technology from a combinatorial library of a single Staphylococcus aureus protein A domain was used. The detection range of IgA standard using an ELISA based on Z(IgA) for capture and goat pAb against IgA (pAb(IgA)) for detection was comparable with that of using pAb(IgA) for both capture and detection. Secondly, another affibody (Z(Apo)) was combined with mAb and used to detect recombinant human apolipoprotein A-1. The affibody/antibody ELISAs were also used to quantify human serum levels of IgA and apolipoprotein A1. To verify that human serum did not cause false-positive signals in the affibody/antibody ELISA format, the ability of human serum to cross-link affibodies, mAb (mouse or rat) and/or pAb (goat) displaying non-matched specificities was assessed; affibodies and antibodies were not cross-linked whereas all combinations of mAb and/or pAb were cross-linked. The combination of affibodies and antibodies for analysis of human serum molecules represents a novel two-site ELISA format which precludes false-positive signals caused by HAIA.  相似文献   
127.
Neisseria sicca osteomyelitis.   总被引:1,自引:0,他引:1       下载免费PDF全文
Neisseria sicca was identified as the cause of vertebral osteomyelitis in a male patient who had previously suffered a nonpenetrating, traumatic back injury. The identifying characteristics and antimicrobial susceptibility patterns are presented for this rare human pathogen, which heretofore has not been reported as a cause of infection localized to bone.  相似文献   
128.
Molecular epidemiological studies of hepatitis C virus (HCV) in the Caribbean may help to specify the origin and spread of HCV infection. Indeed, the Caribbean population is intermixed from European and African origins and geographically close to the American continent. We characterized HCV genotypes in the Caribbean island of Martinique. HCV genotypes were analyzed by sequencing or reverse hybridization in the 5' noncoding region (5'NC) in 250 HCV-monoinfected and 85 HCV-human immunodeficiency virus (HIV)-coinfected patients. In addition, sequencing in the nonstructural 5B (NS5B) gene was required to determine the subtype or to perform phylogenetic analysis in selected samples. Genotypes 1 to 6 were found, respectively, in 84.4, 6.8, 5.2, 2.8, 0.4, and 0.4% of 250 HCV-monoinfected patients and in 71.7, 7.1, 15.3, 5.9, 0, and 0% of 85 HCV-HIV-coinfected patients. HCV-1b was found in 66.4% of the HCV-monoinfected patients and was associated with blood transfusion, whereas HCV-1a was detected in 41.2% of the HCV-HIV-coinfected patients and was associated with intravenous drug use (IVDU). The HCV-3 strains belonged to subtype 3a and were linked to IVDU. Phylogenetic analyses were focused on HCV-2 and HCV-4, which are common in Africa. Two opposite patterns were evidenced. NS5B sequences from 19 HCV-2 isolates were affiliated with many different subtypes described either in Europe or in West Africa, suggesting an ancient radiation. In contrast, seven of the nine HCV-4 NS5B sequences ranged within HCV-4a and HCV-4d clusters spreading in continental France by the IVDU route. Epidemiological data demonstrate the recent introduction of HCV-4a and -4d subtypes into the Caribbean.  相似文献   
129.
BACKGROUND: 'Hospital At Home' schemes are set to increase in the United Kingdom (UK) in response to the NHS Plan. To date, little detailed work has been done on the acceptability of these schemes to patients and their carers. AIM: To compare Hospital at Home patient and carer satisfaction with hospital care. DESIGN OF STUDY: Pragmatic randomised controlled trial. SETTING: Consecutive patients assessed as suitablefor the Leicester Hospital at Home scheme were randomised to Hospital at Home or one of three acute hospitals in the city. METHOD: Patient satisfaction was assessed two weeks after randomisation, or at discharge if later using a six-item questionnaire. Patients' and carers' views of the services were assessed by semistructured interviews. RESULTS: One hundred and two patients were randomised to Hospital at Home and 97 to hospital. Forty-eight (47%) patients in the Hospital at Home arm and 35 (36%) in the hospital arm completed the satisfaction questionnaire, representing 96% and 85% of those eligible, respectively. Total scores were significantly higher in the Hospital at Home (median = 15) than in the hospital group (median = 12). (P<0.001, Mann-Whitney U-test.) Responses to all six questions favoured Hospital at Home, with all but one of these differences being statistically significant. In the Hospital at Homegroup, 24 patients and 18 of their carers were interviewed; in the hospital group 18 patients and seven of their carers were interviewed. Themes emerging from these interviews were that patients appreciated the more personal care and better communication offered by Hospital at Home and placed great value on staying at home, which was seen to be therapeutic. Patients largely felt safe in Hospital at Home, although some would have felt safer in hospital. Some patients and carers felt that better medical care would have been provided in hospital. Carers felt that the workload imposed by Hospital at Home was no greater than by hospital admission and that the relief from care duties at home would be counterbalanced by the added strain of hospital visiting. CONCLUSIONS: Patient satisfaction was greater with Hospital at Home than with hospital. Reasons included a more personal style of care and a feeling that staying at home was therapeutic. Carers did not feel that Hospital at Home imposed an extra workload.  相似文献   
130.
Utilizing real-time computer image analysis, individual spermatozoawere selected using microaspiration. Selection criteria werebased on potential hyperactivation motility characteristics;the amplitude of lateral head displacement >7.5 µm,curvilinear velocity >70 µm/s and linearity of <30%.For this pilot study, 16 patients (eight in each group) wererecruited. Using subzonal insemination (SUZI), up to five (mean= 4.4 ± 0.3) spermatozoa selected using computer-imagesperm selection (CISS) were microinjected, or up to 15 (mean= 12.8 ± 1.3 SD) unselected spermatozoa. In the groupwhich utilized CISS, 28 out of 49 (57%) oocytes were fertilizedcompared with 13 out of 52 (25%) utilizing conventional SUZI(P < 0.04); polyspermy was 20% (n = 10) and 2% (n = 1) respectively.CISS with SUZI showed increased efficiency in achieving fertilizationand is a novel approach to studying individual sperm functionin a sperm egg bioassay where gamete ratios are close to unity.  相似文献   
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