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91.
Copy number of the 16S rRNA gene in Coxiella burnetii 总被引:1,自引:0,他引:1
Coxiella burnetii is an obligate intracellular bacterium with a doubling time of 5–7 hours. Chromosomal DNA from C. burnetii was digested with various restriction enzymes previously determined to not cut within the genomic 16S rRNA gene, or with a combination of these noncutting enzymes in conjunction with AflIII, a restriction enzyme that cuts twice within the 16S rRNA gene. Restriction fragments were resolved electrophoretically and probed with a radiolabeled DNA fragment containing the 3 AflIII portion of the C. burnetii 16S rRNA gene. Only a single DNA fragment in these digests hybridized to the probe, indicating that there is a single genomic copy of the 16S rRNA gene in C. burnetii and thus only a single copy of the rRNA operon. 相似文献
92.
Graham C. Smith Michael H. Winterborn Christopher M. Taylor Nigel Lawson Mark Guy 《Pediatric nephrology (Berlin, Germany)》1994,8(2):148-150
Retinol-binding protein (RBP) is a low molecular weight protein freely filtered at the glomerulus. The fractional tubular reabsorption of RBP is 99.97% and increased excretion is therefore a sensitive marker of tubular dysfunction. We obtained early-morning urine specimens from 151 well children, from newborn to 16 years of age. RBP was measured using an enzyme-linked immunosorbent assay, albumin by a radioimmunoassay and creatinine by a modified Jaffé reaction. Protein excretion was assessed by calculating the protein: creatinine ratio for early-morning urine samples. We found a fall in both RBP and albumin excretion with increasing age, particularly in the 1st year of life, with a much wider variation in values from the infants studied. The mean excretion of RBP for children aged 0–6 months [51.4 (0.6–4,719) g/mmol] was significantly higher (P<0.001) than the mean for children aged 6 months to 16-years [15.0 (3.8–60) g/mmol]. It has been shown that measurement of tubular proteinuria using the RBP: creatinine ratio is useful in the assessment of children with renal disease and we propose a value two standard deviations above the geometric mean for the age of the patient as an upper limit of normal. 相似文献
93.
Dunn RB Guy PM Hardman CS Lewis PA Vetter NJ 《Clinical performance and quality health care》1995,3(3):151-155
OBJECTIVE: To determine whether there was any benefit from a single house call by a health visitor (a public health nurse) to an elderly person after discharge home from a geriatric hospital. METHODS: A randomized controlled trial with blind assessments at 28 days was conducted. Subjects included residents of Bath, England, with an average age of 83 years, who were discharged consecutively from a geriatric hospital to their homes. Intervention was a single visit by a health visitor 72 hours after discharge, to ensure the patient was settled at home, or normal post-discharge care. Outcome measures taken at 28 days by a research nurse included survival, hospital readmissions, nursing home admissions, cognitive and physical function, services requested and supplied, and drug therapy. RESULTS: There were no important differences between the intervention and control groups at 28 days on any of the outcome measurements. The control subjects did better than the study subjects on many of the outcome measures. CONCLUSION: A house call by a health visitor to elderly patients after discharge from geriatric wards does not measurably improve the quality of the discharge. 相似文献
94.
Guy Sallet Winfried M. K. Amoaku Bart A. Lafaut Patrick Brabant Jean Jacques De Lacy 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(11):677-689
Background: Fluorescein angiography (FA) has been widely used in the diagnostic evaluation of cboroidal tumors. Indocyanine green angiography (ICG-A), which permits better visualization of choroidal vasculature than FA, has been recently introduced into clinical practice. Only few reports exist on the ICG-A characteristics of choroidal tumors. Methods: The fluorescein and indocyanine green angiograms of 61 patients were assessed. These included 14 patients with choroidal nevi, 30 with malignant melanomas, 7 with suspected melanomas or atypical nevi, 5 with hemangiomas and 5 with metastases. Results: The outline of pigmented tumors was more accurate on ICG-A than on FA. Characteristic patterns were seen in all intra-ocular tumors with ICG-A, so it was possible to distinguish hemangiomas from malignant lesions. Characteristic features of malignant melanomas include abnormal vascular pattern and marginal late dye leakage. None of the benign lesions showed these features. In suspected melanomas, the presence of abnormal choroidal vascular patterns and/or late dye leakage on ICG-A may indicate malignancy. Conclusion: The study suggests that ICG-A can yield additional information that is useful in differentiating amongst choroidal tumors. Better delineation of pigmented lesions with ICG-A allows more accurate treatment planning and follow-up. 相似文献
95.
Azo polymers based upon 2-hydroxyethyl methacrylate, methyl methacrylate, and methacrylic acid, and containing N,N-bis [(methacryloyloxyethyl)oxy(carbonylamino)]azobenzene as azo aromatic agent were evaluated in vivo as coatings for colon-specific drug delivery. The gastrointestinal absorption of theophylline from capsules coated with the azo polymers was examined in the proximal part of the small intestine and the cecum of male Wistar rats. The capsules were surgically inserted in the region of interest. The plasma concentration of the drug was higher when the capsules were inserted in the cecum as compared to the small intestine. The appearance of theophylline in the plasma when capsules were administered in the small intestine can be attributed to simple diffusion of the drug through the swollen polymer coating. Release and absorption from the cecum is the combined result of diffusion and degradation of the azo polymer coatings by bacterial azo reductase. 相似文献
96.
Rémy M Valli N Brethes D Labrugère C Porté-Durrieu MC Dobrova NB Novikova SP Gorodkov AJ Bordenave L 《Biomaterials》1999,20(3):241-251
In order to improve long-term patency of vascular grafts, the promising concept of endothelial cell seeding is actually under investigation. Our laboratory tested a polyester coated with albumin and chitosan which permits a rapid colonization by human umbilical vein endothelial cells (HUVEC) and it seems relevant to test in vitro the expression of adhesive molecules expressed by cells with regard to the inflammatory process. We studied intercellular adhesion molecule-1 (ICAM-1) expression and focused our work on the determination of ICAM-1 sites expressed per adherent cell lining the biomaterial, thus in situ, in comparison to control HUVEC on plastic wells: the results obtained by binding experiments were correlated to flow cytometry analyses and showed that the polyester does not induce a proinflammatory state and that HUVEC covering the structure are able to respond to a stimulus. 相似文献
97.
98.
Spivak B Lamschtein C Talmon Y Guy N Mester R Feinberg I Kotler M Weizman A 《Clinical neuropharmacology》1999,22(2):98-101
The aim of this retrospective study is to determine whether lipid levels rise in neuroleptic-resistant chronic schizophrenic patients during clozapine treatment and if this rise is correlated with a decrease in aggressive and suicidal behavior. Seventy neuroleptic-resistant schizophrenic patients treated with clozapine for at least 6 months were compared with 30 chronic schizophrenic patients treated with classic antipsychotic agents for the same length of time. Data on serum levels of cholesterol and triglycerides and on aggressive and suicidal behavior, as measured by the Overt Aggression Scale (OAS), were collected in both groups before treatment and 6 months later. A significant reduction in aggressive and suicidal behavior was noted in the clozapine-treated group but not in the classical antipsychotic-treated group. Clozapine treatment was associated with an elevation in serum triglyceride level, whereas classic antipsychotic treatment was associated with an increase in serum cholesterol level. We conclude that serum cholesterol level does not play a role in the clozapine-induced attenuation in aggressive and suicidal behavior in neuroleptic-resistant schizophrenic patients, though the accompanying elevation in triglycerides may be relevant to a behavioral effect. 相似文献
99.
Emre S Sebastian A Chodoff L Boccagni P Meyers B Sheiner PA Mor E Guy SR Atillasoy E Schwartz ME Miller CM 《The Mount Sinai journal of medicine, New York》1999,66(5-6):310-313
In liver transplant (LTx) recipients, gut-associated bacterial and fungal organisms produce significant postoperative morbidity and mortality. We sought to assess the role of selective digestive decontamination (SDD) in preventing postoperative infections in a large single-center cohort of liver recipients transplanted under two non-simultaneous protocols. In 212 consecutive patients transplanted between 1/1/91 and 7/31/92, SDD (gentamicin 80 mg, polymyxin B 100 mg, nystatin suspension 10 mL) was employed, starting after induction of anesthesia and continued until POD 21 (SDD Group). In 157 consecutive patients transplanted between 1/1/93 and 12/31/93, SDD was not used (non-SDD Group). Both groups received IV vancomycin and cefotaxime prophylaxis. All culture-positive infections within the first 30 days post-LTx were recorded and classified as bacterial or fungal. Infection-related mortality (patients who died of infectious complications without any technical complication) was recorded. Groups did not differ in patient demographics, United Network for Organ Sharing (UNOS) status, use of veno-venous bypass, total/warm ischemia, or length of ICU stay. Infections developed in fewer SDD patients (56/212; 26%) than non-SDD patients (69/157; 44%) (p<0.001). The incidence of gram-negative infection was less in the SDD group (11% vs. 26%, p<0. 001) as was gram-positive infection (16% vs. 26%, p<0.001). Among patients who developed infection, there was no difference between groups in infections per patient. Primary graft non-function (PNF) developed in 20 SDD patients (7/20 had infections) and 8 non-SDD patients (6/8 had infections) (p=0.06). There were no differences in incidence of fungal infections or of infection-related mortality between groups. In the SDD group, there were fewer abdominal (p<0. 001), lung (p<0.001), wound (p<0.01), and urinary tract infections (p<0.05). CONCLUSION: Use of SDD in liver recipients early after transplant was associated with significantly fewer infections in the early postoperative period. 相似文献
100.
Pharmaceutical Research - 相似文献