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31.
A polymerase chain reaction (PCR) assay was developed for detection of Chlamydia trachomatis DNA. One primer set was used, from the published sequence of the common C. trachomatis plasmid. Detection of amplified sequences was carried out by agarose gel electrophoresis. Analysis of 106 clinical samples tested by cell culture and PCR showed a sensitivity of 100% when PCR was compared with cell culture.  相似文献   
32.
OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery.  相似文献   
33.
A strain of Aspergillus fumigatus has been isolated from sediments of a mussel bed. When cultured in hyper saline conditions (with sea-water), it produces a cytotoxic and immunosuppressive toxin, gliotoxin, which is excreted in an exudate. In order to know if this toxin could represent a risk for shellfish consumers, an experiment of bioaccumulation of gliotoxin in mussel has been carried out. After 6 days of contamination, toxin was accumulated in the meat of the mussels, at a level up to 2.9 microg/mg of extract weight, with a mode of contamination different to the classical digestive process described for a majority of marine toxins, but similar to the contamination mode of domoic acid.  相似文献   
34.
Prediction of hemorrhagic transformation (HT) in patients treated by intravenous recombinant tissue-type plasminogen activator (rt-PA) is a challenging issue in acute stroke management. HT may be correlated with severe hypoperfusion. Signal changes may be observed at susceptibility-weighted magnetic resonance imaging (MRI) within large perfusion defects. A signal drop within cerebral veins at T2*-weighted gradient-echo MRI may be expected in severe ischemia, and may indicate subsequent risk of HT. The authors prospectively searched for an abnormal visibility of transcerebral veins (AVV) within the ischemic area in patients with hemispheric ischemic stroke, before they were treated with intravenous rt-PA therapy. Any correlation between AVV and baseline clinical or MRI findings, or further HT, was noted. An AVV was present in 23 of 49 patients (obvious, n = 8; moderate, n = 15), and was supported by severe hemodynamic changes at baseline MRI. The AVV was correlated with the occurrence of parenchymal hematoma type 2 at computed tomography during the first week (r = 0.44, P = 0.002). Five of six type 2 parenchymal hematomas occurred in association with obvious AVV. At multiple regression analysis, two baseline MRI factors had an independent predictive value for HT risk during the first week: the AVV and the cerebral blood volume ratio (Nagelkerke R2 = 0.48).  相似文献   
35.
Biochemical results concerning 64 patients suspected of mitochondrial myopathies are presented. Four clinical groups were studied including 21 encephalomyopathies, 42 ocular myopathies, 8 isolated myopathies and 3 cardiomyopathies. In 26 cases, the coexistence of a normal mitochondrial DNA and a mutated mitochondrial DNA (heteroplasmy) was found (19 simple deletions, 4 multiple deletions and 3 punctual mutations) and all cases presented with ocular disorders (excepted 2 cases with MERRF). Furthermore, 1 complex I deficiency (1 ocular myopathy), 1 complex IV deficiency (1 adult encephalomyopathy type Leigh), 3 complexes I + IV deficiencies (2 cases with a cardiomyopathy and 1 familial MELAS) and 2 pyruvate (1 adult from of Leigh's encephalomyopathy) dehydrogenase deficiencies (clinically and genetically different) did not show evidence of mitochondrial DNA mutation.  相似文献   
36.
Extreme bradycardia during sleep apnea caused by myxedema   总被引:1,自引:0,他引:1  
A 52-year-old man with myxedema was evaluated for anterior chest pain that was considered to be compatible with myocardial ischemia. The night after admission he developed extreme bradycardia, hypotension, and apneic episodes lasting up to 25 s. Continuous positive airway pressure and administration of medroxyprogesterone acetate prevented further episodes and relieved much of the somnolence and lethargy that had contributed to the evidence for myxedema. Alveolar hypoventilation caused by decreased sensitivity to carbon dioxide, inadequate central neural drive, peripheral muscle force, and obesity all may have contributed to the apnea. Chest pain has not recurred, and results of electrocardiography have remained normal following full thyroid hormone replacement. The early recognition of myxedema causing sleep apnea will allow specific treatment to avoid the cardiovascular risks related to prolonged apnea and will help avoid confusion with other etiologies of cardiovascular abnormalities.  相似文献   
37.
38.
Adherence of bacteria to corneal epithelium is a prerequisite for corneal infection. We used two methods to study the binding of Pseudomonas aeruginosa and Staphylococcus aureus to rabbit corneal epithelial cells in culture. In the first method, rabbit corneal epithelial cells grown on glass slides were incubated with P. aeruginosa or S. aureus (10(7) CFU/ml) at room temperature for 90 min, and the bacterial binding to the epithelial cells was examined by light microscopy. Both P. aeruginosa and S. aureus bound to epithelial cells. P. aeruginosa was bound to the cell periphery whereas S. aureus was bound randomly to the cell surface. In the second method, suspension cultures of corneal epithelial cells were used. In contrast to the findings in cultures on slides, binding pattern with cells in suspension was similar for both species and resembled that for S. aureus in cultures on slides. A much greater number of P. aeruginosa (186 +/- 11 bacteria/epithelial cell) than S. aureus (30 +/- 1.5 bacteria/epithelial cell) bound to epithelial cells grown on glass slides. In contrast, a similar number of P. aeruginosa (25 +/- 5.1) and S. aureus (20 +/- 4.7) bound to epithelial cells grown in suspension cultures. Using either method, Escherichia coli and Streptococcus pyogenes did not bind significantly (less than 5/cell) to corneal epithelial cells. The above methods should prove useful for characterization of bacterial binding to corneal epithelial cells in culture.  相似文献   
39.
This prospective study was initiated 3 years ago to evaluate the outcome and to identify predictors of success or failure in patients admitted to a rehabilitation program for chronic low-back pain. Multiple parameters were evaluated, including psychologic data (MMPI, personal interview, pain drawing, etc.), physical measurements (flexibility, strength and endurance), and demographic data concerning the patient's home and working environment. Information was available on each patient admitted to the program prior to his admission, at completion of the program, 6 weeks following completion of the program and 3 months following completion of the program. A telephone interview was carried out 2 1/2 years following the patient's discharge from the program. Linear regression analysis was used to identify the important independent variables with regard to the dependent variables of relief of back pain, return to work and increased activities at home. Demographic data were of no value as a predictor with the exception of age and returning to work. The patients over the age of 50 returned to work with much less frequency than those less than 50. Psychologic information from the MMPI and similar tests were of no value. The personal preadmission interview of a trained psychologist, however, was a good predictor of an individual's eventual return to work and overall improvement. Worker's Compensation and other litigation was a negative factor in a patient's prognosis. The treatment team's prognosis at the time of discharge from the program was the best overall predictor of a patient's chance of success or failure in the longterm.  相似文献   
40.
BACKGROUND: Conventional and atypical antipsychotics have different affinities for D2 receptors, and these receptors are principally located in the striatum. Given that this cerebral structure was previously found to play a major role in procedural learning, the antipsychotic treatment in schizophrenia may be determinant for the procedural learning profile of these patients. OBJECTIVE: The current study was aimed at verifying whether procedural learning differs in patients with schizophrenia treated with conventional antipsychotics and patients treated with atypical antipsychotics. METHOD: Forty-five patients with schizophrenia were divided into 3 different groups according to their pharmacologic treatment: (1) haloperidol, a classical neuroleptic with high D2 receptor affinity; (2) clozapine, an atypical neuroleptic with practically no D2 receptor affinity; and (3) risperidone, an atypical neuroleptic that nevertheless shows high D2 receptor affinity. Patients were compared to 35 control subjects on a visuomotor procedural learning task (mirror drawing). RESULTS: All patients were able to learn the task. However, those treated with haloperidol showed some degree of learning impairment, while those treated with clozapine or risperidone did not show this impairment. In addition, performance per se, regardless of the learning, was found to be affected in the haloperidol and risperidone, but not in the clozapine groups. CONCLUSION: Procedural learning in schizophrenia may be differentially affected, depending on the pharmacologic profiles of the antipsychotics used for the treatment of this illness.  相似文献   
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