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81.
82.
OBJECTIVE: Our purpose was to measure the impact of a single-layer or double-layer closure on uterine rupture at subsequent delivery. STUDY DESIGN: This is an observational cohort study of all women undergoing a trial of labor from 1988 to 2000 in a tertiary care center, after a single low transverse cesarean delivery. Factors most highly associated with uterine rupture were identified by using univariate regression analysis. Multivariate logistic regression analysis was used to adjust for selected confounding variables. RESULTS: Of the 2142 women who met the study criteria, 1980 (92.4%) had maternal records and original operative reports reviewed. After adjustments were made for confounding variables, the odds ratio for uterine rupture in women with a single-layer closure was 3.95 (95% CI, 1.35-11.49). CONCLUSION: A single-layer closure of the previous lower segment incision was the most influential factor and was associated with a 4-fold increase in the risk of uterine rupture compared with a double-layer closure.  相似文献   
83.
BACKGROUND/OBJECTIVES: The mechanical aerosol generator, MAGhaler, is a new chlorofluorocarbon-free inhalation device. The objective of this trial was to show equivalent efficacy and safety of beclomethasone dipropionate (BDP) delivered via the MAGhaler and the metered-dose inhaler (MDI) in patients with mild to moderate bronchial asthma. Moreover, user-friendliness and acceptance of the two devices were compared. METHODS: This was a double-blind, reference-controlled, 12-week trial in 171 patients with asthma receiving BDP (1,000 microg/day) delivered via either the MAGhaler or the conventional MDI. Respiratory function parameters, clinical symptoms, concomitant intake of salbutamol or fenoterol, adverse events (AEs), laboratory values, and concomitant medications and diseases were recorded. The primary efficacy parameter was mean forced expiratory volume in 1 s (FEV1), measured after 4, 8, and 12 weeks of therapy. RESULTS: The equivalence of the two devices was confirmed (p = 0.003) on the basis of the ratios of the mean FEV1 in weeks 4 to 12. Mean (+/- SD) FEV1 (MAGhaler was 2.24 +/- 0.60 l (baseline), 2.61 +/- 0.90 litres (week 4), and 2.62 +/- 0.87 litres (weeks 4-12). Mean FEV1 (MDI) was 2.28 +/- 0.59 litres (baseline), 2.53 +/- 0.82 litres (week 4), and 2.56 +/- 0.77 litres (weeks 4-12). In total, 33 AEs occurred in 26 (30.2%) patients (MAGhaler) and 51 AEs in 36 (42.4%) patients (MDI). Most of the AEs were of mild or moderate intensity. The relationship to treatment could not be excluded for 11 AEs in 11 patients (MAGhaler) and 23 AEs in 18 patients (MDI). Three serious AEs, all unrelated to treatment, occurred in 3 patients (MAGhaler: 2, MDI: 1). There were no clinically relevant changes in other safety parameters. Most patients either preferred the MAGhaler or rated the two devices as equally acceptable. CONCLUSION: The new MAGhaler was equivalent to the standard MDI in terms of the safety and efficacy of BDP. The improved user-friendliness and acceptance of the MAGhaler over the conventional MDI represent an important advance in the clinical management of bronchial asthma.  相似文献   
84.
Efroni S  Harel D  Cohen IR 《Genome research》2003,13(11):2485-2497
One of the problems biologists face is a data set too large to comprehend in full. Experimenters generate data at an ever-growing pace, each from their own niche of interest. Current theories are each able, at best, to capture and model only a small part of the data. We aim to develop a general approach to modeling that will help broaden biological understanding. T-cell maturation in the thymus is a telling example of the accumulation of experimental data into a large disconnected data set. The thymus is responsible for the maturation of stem cells into mature T cells, and its complexity divides research into different fields, for example, cell migration, cell differentiation, histology, electron microscopy, biochemistry, molecular biology, and more. Each field forms its own viewpoint and its own set of data. In this study we present the results of a comprehensive integration of large parts of this data set. The integration is performed in a two-tiered visual manner. First, we use the visual language of Statecharts, which makes specification precise, legible, and executable on computers. We then set up a moving graphical interface that dynamically animates the cells, their receptors, the different gradients, and the interactions that constitute thymic maturation. This interface also provides a means for interacting with the simulation.  相似文献   
85.
A prospective study was conducted to determine the association between pneumococcal carriage among 36 infants and young toddlers cared for at home and carriage among their older siblings who attended 8 day-care centers (DCCs); 71 pneumococcal strains acquired by the younger siblings were compared with those present in the DCCs for 6 months. In 76% of cases, > or =1 strain identical by serotype and antibiogram was isolated in the older siblings' DCC versus 32%-63% in all other DCCs (P<.001). When phenotypically identical strains were compared by pulsed-field gel electrophoresis, the similarity between strains from older siblings' DCCs and the younger siblings' isolates was striking. This was not found when isolates from other DCCs were compared. Vaccinating DCC attendees with a 7-valent pneumococcal conjugate vaccine may play a key role in controlling the spread of antibiotic-resistant pneumococci, because the most resistant serotypes are included in the vaccine.  相似文献   
86.
Cardiac embolism accounts for a large proportion of ischemic stroke. Revascularization using systemic or intra-arterial thrombolysis is associated with increasing risks of cerebral hemorrhage as time passes from stroke onset. We report successful mechanical thrombectomy from a distal branch of the middle cerebral artery (MCA) using a novel technique. A 72-year old man suffered an acute ischemic stroke from an echocardiographically proven ventricular thrombus due to a recent myocardial infarction. Intra-arterial administration of 4 mg rt-PA initiated at 5.7 hours post-ictus failed to recanalize an occluded superior division branch of the left MCA. At 6 hours, symptomatic embolic occlusion persisted. Mechanical extraction of the clot using an Attracter-18 device (Target Therapeutics, Freemont, CA) resulted in immediate recanalization of the MCA branch. Attracter-18 for acute occlusion of MCA branches may be considered in selected patients who fail conventional thrombolysis or are nearing closure of the therapeutic window for use of thrombolytic agents.  相似文献   
87.
The growing availability of sequences of bacterial genomes has revealed a number of open reading frames predicted by sequence alignment to encode antibiotic resistance proteins. The presence of these putative resistance genes within bacterial genomes raises important questions regarding potential reservoirs of resistance elements and their evolution. Here we examine four gene products encoding predicted aminoglycoside-aminocyclitol antibiotic modifying enzymes, two phosphotransferases and two acetyltransferases, derived from analysis of the genome sequence of Mycobacterium tuberculosis strain H37Rv with the goal of assigning biochemical function by purification of each protein and characterization of their ability to modify aminoglycoside antibiotics. Only one of these enzymes, the previously characterized aminoglycoside acetyltransferase AAC(2')-Ic, displayed compelling aminoglycoside modifying activity. While the putative phosphotransferase encoded by the Rv3225c gene did display low levels of aminoglycoside kinase activity, the predicted kinase encoded by the Rv3817 gene lacked any such activity. A potential aminoglycoside 6'-acetyltransferase, encoded by the Rv1347c gene, did not show antibiotic acylation activity but did demonstrate selective thioesterase activity with numerous acyl-CoAs. This activity, together with the genomic environment of the Rv1347c gene in a likely polyketide synthesis cluster, suggests a role for this protein in secondary metabolism and not in antibiotic modification. It was thus shown that only one of four putative aminoglycosides modifying enzymes derived from the whole genome sequencing of M. tuberculosis H37Rv showed sufficient predicted enzyme activity to be annotated as an aminoglycoside resistance element. This study demonstrates the necessity of biochemical annotation methods as a follow up to in silico sequence alignment-based methods of assigning gene product function.  相似文献   
88.
Patients with ventriculo-peritoneal shunts are predisposed to various complications, including the appearance of seizures over time. The high rate of complications prompted an interest in alternative procedures such as endoscopic third venticulostomy (ETV) in selected patients. From 1996 to 1998, 42 patients underwent ETV in our center. Of the 27 operated children who were followed for an average of 32 months, none experienced seizures during that time. We conclude that, in addition to other benefits, ETV minimizes the risk of epilepsy following shunt insertion, probably due to the lack of direct cortical insult.  相似文献   
89.
Recent research demonstrates the importance of inflammatory parameters in the etiology and prognosis of the acute coronary syndrome (ACS). This study explored relations between psychological factors and immunological parameters routinely measured among ACS patients. Forty-two ACS patients completed questionnaires assessing perceived-control, emotional support, hostility, and life-events 2-4 days after hospitalization. Data on total leukocytes and percentages (%) of monocytes, %neutrophils, and %lymphocytes upon admission to hospital were collected from computerized medical charts as well as various biomedical information and risk-factors (e.g., diagnosis, left-ventricle-LV functioning, smoking, and hypertension). Of all significant biomedical variables, LV-function and arrival-time correlated uniquely with total leukocytes. Controlling for LV-function and arrival-time, hostility and life-events positively correlated with %monocytes, and perceived-control and emotional-support inversely correlated with %monocytes. Emotional-support was positively correlated and life-events were negatively correlated with %neutrophils. Macrophages play a pivotal role in plaque instability, the trigger of an ACS. This initiating role, and our finding of a relationship between recruitment of monocytes and a poor psychosocial profile, predictive of ACS, are consistent with a PNI component in the pathophysiology of ACS.  相似文献   
90.
BACKGROUND: This study evaluated the ability of a modified cell separator (Cobe Spectra Apheresis) system to isolate monocytes (MOs) by elutriation. The evaluation was performed in two independent international laboratories. The capacity of collected MOs to differentiate into dendritic cells (DCs) was also assessed. STUDY DESIGN AND METHODS: MNCs from platelet apheresis residues were elutriated on a modified cell separator (Cobe Spectra Apheresis system) using a custom disposable set. Cells were separated according to their size and density. Recovery and purity of the collected cell product were evaluated by impedance counting and flow cytometry. DCs were differentiated in culture from the elutriated MOs and characterized by their surface markers and stimulatory capacity in a mixed WBC reaction assay. RESULTS: Six apheresis mononuclear cell products were used by each laboratory. The separation was achieved in less than 1 hour. Collected MOs had the potential to differentiate into DCs. CONCLUSION: The modified cell separator is an easy and fast device to obtain highly enriched MOs with a DC differentiation potential. The system is closed and employs a single-use disposable set and is more amenable to good tissue practice. This method could become a valuable tool for DC-based active immunotherapy.  相似文献   
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