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51.
STUDY OBJECTIVE: To investigate the effect of Pseudomonas aeruginosa infection on clinical parameters in Chinese patients with noncystic fibrosis and steady-state bronchiectasis. DESIGN: Prospective, cross-sectional clinicomicrobiological study with informed consent. SETTING: Consecutive outpatient recruitment from a specialist bronchiectasis respiratory clinic. PATIENTS: Outpatients (n = 100; 62 women; 55.1+/-16.7 years old; FEV1/FVC 1.4+/-0.7/2.1+/-0.9 L), who had stable respiratory symptoms for more than 3 weeks. MEASUREMENTS AND RESULTS: Respiratory pathogens isolated from the sputum were: Pseudomonas aeruginosa (33), Haemophilus influenzae (10), Moraxella catarrhalis (2), other Gram-negative bacilli (5), Streptococcus pneumoniae (6), Staphylococcus aureus (5), mycobacteria (3), and yeast (1). Clinical parameters in patients with positive isolation of P aeruginosa were compared with those without the organism in the sputum culture (non-P aeruginosa). In the P aeruginosa group, the FEV1/FVC ratio and sputum volume were lower (p < 0.005) and higher (p < 0.0001), respectively, than those of the non-P aeruginosa group. The FEV1/FVC ratio (< 60%) and sputum volume (grading > 5) were independently associated with a positive sputum isolation of P aeruginosa with odds ratios of 3.1 (confidence interval [CI] 1.2 to 8.4; p < 0.01) and 4.7 (CI 1.6 to 13.3; p < 0.001), respectively. CONCLUSIONS: P aeruginosa is the predominant respiratory pathogen isolated in the sputum of Chinese patients with steady-state bronchiectasis, and its isolation is associated with high sputum output (> or = 75th quartile) and moderately severe airflow obstruction (FEV1/FVC < 60%).  相似文献   
52.
OBJECTIVE: To assess the ability of certain derivatives of beta-cyclodextrin to treat sheep affected by tunicaminyluracil toxicity, using tunicamycin poisoning as a model system. DESIGN: Controlled treatment trial. ANIMALS: One hundred and sixty Merino wethers were used in the studies. PROCEDURE: Groups of sheep were experimentally poisoned with tunicamycin. Derivatives of beta-cyclodextrin, with or without magnesium sulphate and magnesium gluconate, were administered to treatment groups daily for 2 to 3 days. Treatment groups were compared with untreated groups in terms of survival. RESULTS: A significant increase in survival was observed following treatment of tunicamycin-affected sheep with hydroxypropyl-beta-cyclodextrin (HP beta-CD) and magnesium sulphate in solution (P < 0.05). In subsequent trials, formulation of the cyclodextrin in the form of a magnesium gluconate gel suspension demonstrated significant protection (P < 0.01) and was equally as effective as the cyclodextrin in solution, but required half the frequency of administration, even when the treatment was not commenced until 24 h after the final toxin dose. Beta-cyclodextrin-epichlorohydrin copolymer also improved the survival rate. After toxin administration, the sheep lost significantly less weight if treatment with HP beta-CD was commenced early (P < 0.001). CONCLUSION: Protection studies using these two beta-cyclodextrin derivatives suggest that they may be effective in increasing the survival of sheep poisoned by tunicamycin and warrant further testing in field outbreaks of annual ryegrass toxicity.  相似文献   
53.
This study compared PCR and an assay for cytomegalovirus (CMV) pp65 antigenemia (CMV-vue; INCSTAR Corp.) with a quantitative shell vial culture (QSVC) technique for the detection of CMV in serial blood specimens from 46 solid-organ transplant recipients. In a comparison based on 535 specimens tested by PCR and QSVC, CMV was detected by PCR in 41 and by QSVC in 37 of 43 recipients at risk of CMV infection. The mean number of days after transplantation of initial detection of CMV was 29.9 for PCR and 34.0 for QSVC (P = 0.01). The antigenemia assay was performed on 395 specimens, including 304 of those also tested by PCR. In these specimens, CMV was detected by the antigenemia assay, QSVC, and PCR in 30, 32, and 35 (respectively) of 38 patients at risk, with no statistically significant difference in the time to detection. Each of the assays detected CMV in similar proportions of patients with and without clinically significant CMV infection. PCR stayed positive longer after transplantation than the other assays but frequently returned to negative when more than 6 months had elapsed after transplantation. The antigenemia assay and PCR stayed positive longer after institution of antiviral therapy than QSVC. PCR can provide highly sensitive detection of CMV viremia, but a PCR assay for CMV is not yet available in kit form. The pp65 antigenemia assay and shell vial culture are quantifiable and comparable in sensitivity. Either is recommended for rapid detection of CMV in blood specimens from solid-organ transplant recipients.  相似文献   
54.
The DBP5 gene encodes a putative RNA helicase of unknown function in the yeast Saccharomyces cerevisiae. It is shown here that Dbp5p is an ATP-dependent RNA helicase required for polyadenylated [poly(A)+] RNA export. Surprisingly, Dbp5p is present predominantly, if not exclusively, in the cytoplasm, and is highly enriched around the nuclear envelope. This observation raises the possibility that Dbp5p may play a role in unloading or remodeling messenger RNA particles (mRNPs) upon arrival in the cytoplasm and in coupling mRNP export and translation. The functions of Dbp5p are likely to be conserved, since its potential homologues can be found in a variety of eukaryotic cells.  相似文献   
55.
56.
Over 100 years ago, Florence Nightingale showed caregivers how to analyze mortality data to improve their clinical processes. The nurses of today are facing a new performance measurement challenge. Consumers of health care services want information that will help them compare quality among providers. This article describes the types of nursing performance measures most appropriate to include on these public-oriented report cards and several issues that influence report card design and dissemination.  相似文献   
57.
Magnesium chloride (MgCl2) has been proposed for the treatment of seizures of different etiologies. The present study investigated the effect of MgCl2 on aldrin-induced seizures. Initially, 50 male rats received 60 mg aldrin/kg po and the effects were classified as muscular twitches, clonic convulsions or tonic-clonic convulsions. Another group of 40 rats dosed with 60 mg aldrin/kg po received 0, 4, 8, or 12 mg MgCl2/kg i.m. The percentage of tonic-clonic convulsant rats that resulted from MgCl2 treatment were 90% at 0 mg/kg, 50% at 4 mg/kg, 40% at 8 mg/kg and 20% at 12 mg MgCl2/kg. The percentage of survivors in the group receiving 12 mg MgCl2/kg was 80% while the control group had 20% survival. The clonic convulsions were not modified by MgCl2 treatment. Blood and brain concentrations of aldrin and dieldrin (metabolite of aldrin) did not differ among groups. The MgCl2 administration decreased the neuroexcitability induced by aldrin and increased survivability.  相似文献   
58.
PURPOSE: Interpretation time of serial staging chest CT cases, which each contained current and previous examinations, with a simple prototype workstation called filmstack was experimentally compared with interpretation time with a film alternator. MATERIALS AND METHODS: The filmstack displayed a "stack" of sections for each examination; user controls allowed rapid selection of preset attenuation windows and both synchronized and unsynchronized scrolling. Eight radiologists were timed as they used the filmstack and the film alternator to interpret four ergonomically complex serial CT cases. RESULTS: All reports dictated on the basis of findings with filmstack and film were of acceptable clinical accuracy. The time to examine a case with filmstack was significantly faster than the time with film, including the time to load and unload the alternator (99% confidence [P = .01]). There was no statistically significant difference in interpretation time between filmstack and prehung film. CONCLUSION: Use of a low-cost stacked CT workstation with a single 1,024 x 1,024 monitor is an effective means of interpreting cases that require comparison of multiple CT examinations.  相似文献   
59.
During the last few years, morphological, immunohistochemical, and genetic findings have placed anaplastic large cell lymphoma (ALCL) as a distinct clinicopathologic entity, and several reports have focused on the existence of different subtypes of the tumor. Particular attention has been paid to the ALCL-Hodgkin's-like (HL) subtype, which seems to be on the border between Hodgkin's disease (HD) and high-grade non-Hodgkin's lymphoma (HG-NHL). From September 1994 to July 1997, during the course of an Italian multicentric trial, 40 ALCL-HLs were randomized to receive as front-line chemotherapy MACOP-B (methotrexate with leucovorin, doxorubicin, cyclophosphamide, vincristine, prednisone, and bleomycin-a third-generation HG-NHL regimen) or ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine-a scheme specific for HD). All patients with bulky disease in the mediastinum at diagnosis underwent local radiotherapy after the chemotherapeutic program. Complete response (CR) was achieved in 17 of the 19 (90%) patients who were treated with MACOP-B, and in 19 of the 21 (91%) patients who were administered ABVD. The probability of relapse-free survival, projected at 32 months, was 94% for the MACOP-B subset and 91% for the ABVD subset. The majority of patients with mediastinal bulky disease obtained CR (evaluated with 67Ga single photon emission computed tomography [SPECT]) after their radiotherapy. The present study suggests that ALCL-HL, in line with its borderline status, responds in an equivalent way to third-generation chemotherapy for HG-NHL and to conventional HD treatment in terms of both CR and relapse-free survival rates. However, as to the latter, a longer follow-up period may be needed before stating the absolute equivalence of the two regimens used.  相似文献   
60.
OBJECTIVE: Our purpose was to evaluate and compare the perioperative morbidity and the long-term results of the Raz colposuspension and the Bologna operation for the treatment of stress urinary incontinence in women. STUDY DESIGN: Data of 188 women who underwent either a Bologna operation (group 1) or a Raz colposuspension (group 2) for the treatment of stress urinary incontinence between January 1, 1987 and December 1, 1995 were analysed retrospectively regarding history, preoperative evaluation, associated surgical procedures, complications and cure and failure rate. POPULATION AND METHODS: 80 patients were treated with the Bologna operation and 108 with the Raz colposuspension. Patients with prior anti-incontinence surgery, and patients with a preoperative diagnosis of urge incontinence were excluded from the study. Success was defined both subjectively (complete absence of complaint of stress urinary incontinence) and objectively (no evidence of loss of urine on cough provocation during physical examination). Survival curves were generated in each group for time to event data: "time to recurrent stress incontinence" and compared by the logrank test. A multivariate analysis using a Cox proportional hazards regression model was performed to indentify possible outcome predictors. RESULTS: The success rate of group 1 was significantly higher than that of group 2 (p = 0.00001). The median of success was 51 months in group 1 and 21 months in group 2 (p = 0.00001). The incidence of intraoperative complications in each group (inadvertent cystostomy, hemorrhage) did not differ. The multivariate analyses using the Cox regression model showed that the most highly correlated variable with the surgical cure rate was the type of surgical anti-incontinence procedure adopted: Bologna or Raz (p = 0.00001) CONCLUSION: In our hands, the Bologna operation has a higher cure rate than the Raz colposuspension. For us, when treating patients with stress urinary incontinence by the vaginal route, the Bologna operation is indicated when sufficient anterior vaginal tissue is available to create vaginal bands.  相似文献   
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