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Effective prevention of recurrent urinary tract infections (UTIs) and possible acute pyelonephritis is of major importance during pregnancy. During 39 pregnancies, 33 women with a history of recurrent UTIs (and, in some instances, pyelonephritis) received postcoital prophylaxis consisting of a single oral dose of either cephalexin (250 mg) or nitrofurantoin macrocrystals (50 mg). While 130 UTIs occurred during a mean observation period of 7 months before prophylaxis, only a single UTI occurred during pregnancy after prophylaxis; this difference was highly significant. Thus the use of one of these effective regimens is strongly recommended for any pregnant woman with a history of recurrent UTIs. The treatment's effectiveness can be explained by two features of the two antibacterial agents involved: both reach high bactericidal concentrations in the urinary tract and induce no (or minimal) resistance in the introital gram-negative bacterial flora. 相似文献
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Infected renal stones can be treated by extracorporeal shock wave lithotripsy but it still is not clear whether successful stone fragmentation and the disappearance of all macroscopic stone fragments guarantee eradication of the infection. Therefore, a prospective study was done in 135 patients with renal or upper ureteral stones associated with persistent urinary tract infection. The urinary infection was localized in each patient by bilateral ureteral catheterization. Upper tract infection in the kidney containing the stone was found in 75.6 per cent of the cases. A total of 94 patients completed treatment with extracorporeal shock wave lithotripsy and were followed for 3 to 16 months (mean followup 6.4 months). A marked correlation between the incidence of residual macroscopic stone fragments and the presence of persistent infection was noted. Of the 51 patients who became free of stones 48 (94 per cent) had sterile urine. Only 3 of the 51 patients had persistent infection in the treated kidney despite complete disappearance of the stones. In 45 of the 59 patients with stones smaller than 2 cm. (76 per cent) the infection was eradicated, whereas of the 35 with larger stones the urine became sterile in only 13 (37 per cent). We conclude that extracorporeal shock wave lithotripsy can be endorsed for treatment of small infected stones but it is inadequate for treatment of stones larger than 2 cm. unless combined with percutaneous nephrolithotripsy or chemical dissolution of the residual infected fragments. 相似文献
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Arenaviruses: Cellular Response to Long-Term In Vitro Infection with Parana and Lymphocytic Choriomeningitis Viruses 总被引:4,自引:2,他引:4 下载免费PDF全文
L. D. Staneck R. S. Trowbridge R. M. Welsh E. A. Wright C. J. Pfau 《Infection and immunity》1972,6(4):444-450
Persistent infections were established in suspension cultures of BHK21/13S cells with both Parana and lymphocytic choriomeningitis viruses. Four generations after infection with either virus, more than 90% of the cells scored as infective centers, with concomitant peaks in extracellular virus yields. In both cultures the synthesis of detectable plaque-forming units (PFU) ceased about the 50th generation postinfection, and this condition was maintained until the 350th cell generation when the cultures were discontinued. The generation time of each culture was identical to that of uninfected parent controls, and at no time were cytopathic effects evident. In spite of the absence of infectivity, over 90% of the cells sampled at various times contained viral antigen demonstrable by immunofluorescence. When either of these persistently infected cell lines was substituted for normal cells in the standard plaque assay, very low efficiencies of plating were observed for homotypic and heterotypic viruses. Plaque formation by several heterologous viruses was virtually unaffected. The mechanism of homotypic plaque exclusion in both cell lines was shown to occur beyond the virion adsorption stage. The original infecting virus genome persisted in both cell lines after standard virus was no longer detectable. This was shown with the lymphocytic choriomeningitis virus-infected cells after storage in liquid nitrogen. After thawing, such cells were found to synthesize standard virus for a brief period. Although the Parana virus-infected cells did not behave this way, the growth medium from these cells would initiate PFU synthesis in normal cells within 36 hr after infection. 相似文献
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Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
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This study analyses the influence of female and male patient age and human
menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and
live birth rates with ovulation stimulation using HMG in combination with
intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI
treatment cycles in 184 patients carried out at a university fertility
centre were analysed in a retrospective fashion. The main outcomes measured
were clinical pregnancy rates and live birth rates. Increased female
partner age (> or = 35) and male partner age (> or = 40) were found
to negatively influence pregnancy rates with HMG/ IUI therapy. In addition,
this study demonstrated a critical threshold of HMG requirements beyond
which pregnancy did not occur. No pregnancies occurred in treatment cycles
requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular
maturity, irrespective of patient age. In conclusion, female partner age,
male partner age, and HMG requirements all significantly influence
pregnancy rates with HMG/IUI therapy.
相似文献
10.
INTRODUCTION: Core biopsy of the breast has become the method of choice for tissue diagnosis of screen detected microcalcifications and some mass lesions in many breast assessment centres. Biopsy results are not available until the following day. Imprint cytology of fresh breast core samples allows same-day reporting and patient counselling.
AIM: To determine the accuracy of core imprint cytology when compared with core biopsy diagnosis when used in a breast assessment centre setting.
METHODS: Core imprints (CI) were prepared and reported on all fresh core biopsies (CB) performed at the Sir Charles Gairdner Hospital Breast Centre from May to December 2000. Fresh core samples were placed on a glass microscope slide. Core radiographs were taken for microcalcification lesions (MC). A laboratory technician gently and quickly rolled the cores on the slide with fine forceps. The cores were fixed in formalin, processed and reported next day. The imprint slide was air dried and stained with DiffQuik. CI were reported using four categories: Insufficient, Benign, Indeterminate and Malignant. Counselling and planning for management were possible on the same day in women with malignant diagnoses. Clinicians were advised not to discuss negative or indeterminate CI results with women and to defer to the final CB report.
RESULTS: Cores were performed on 381 lesions. There were 83 carcinomas (38 in MC and 45 in masses) and 56 were called malignant on CI (absolute sensitivity 67.5%; 78.9% for MC and 57.8% for masses). 3 malignancies on CB were negative on CI giving a false negative rate of 3.6%. There were no false positive diagnoses. The predictive value of a benign diagnosis was 95.3%. There were no adverse effects in the histology of CB.
CONCLUSION: CI was an accurate method of providing an immediate diagnosis of malignancy in two thirds of malignancies confirmed on CB. 相似文献
AIM: To determine the accuracy of core imprint cytology when compared with core biopsy diagnosis when used in a breast assessment centre setting.
METHODS: Core imprints (CI) were prepared and reported on all fresh core biopsies (CB) performed at the Sir Charles Gairdner Hospital Breast Centre from May to December 2000. Fresh core samples were placed on a glass microscope slide. Core radiographs were taken for microcalcification lesions (MC). A laboratory technician gently and quickly rolled the cores on the slide with fine forceps. The cores were fixed in formalin, processed and reported next day. The imprint slide was air dried and stained with DiffQuik. CI were reported using four categories: Insufficient, Benign, Indeterminate and Malignant. Counselling and planning for management were possible on the same day in women with malignant diagnoses. Clinicians were advised not to discuss negative or indeterminate CI results with women and to defer to the final CB report.
RESULTS: Cores were performed on 381 lesions. There were 83 carcinomas (38 in MC and 45 in masses) and 56 were called malignant on CI (absolute sensitivity 67.5%; 78.9% for MC and 57.8% for masses). 3 malignancies on CB were negative on CI giving a false negative rate of 3.6%. There were no false positive diagnoses. The predictive value of a benign diagnosis was 95.3%. There were no adverse effects in the histology of CB.
CONCLUSION: CI was an accurate method of providing an immediate diagnosis of malignancy in two thirds of malignancies confirmed on CB. 相似文献