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Susceptibility to beta-lactam antibiotics of strains of Enterobacteriaceae consecutively isolated in nine general hospitals during a period of 2 months (march and april) has been studied by the disk-agar diffusion method. The separation between susceptible and resistant strains was based on the measure of the inhibition zones centered by 2 disks: cephalothin and ticarcillin. Enterobacteriaceae were divided in 2 groups: strains isolated during the first 48 h of hospitalisation or isolated after. Fifty one per cent of the strains were isolated during the first 48 h: they did not belong to the residential flora of these hospitals. Klebsiella, Proteus indole positive, Providencia, Enterobacter, Serratia were more frequently isolated after 48 h of hospitalisation. Susceptible strains of Klebsiella, Proteus indole positive, Providencia, Serratia were more rarely isolated after 48 h of hospitalisation. E. coli whatever the duration of hospitalisation, is the less frequent susceptible bacterium.  相似文献   
94.
A retrospective analysis, covering a period of 20 years, of 2049 primo-isolates ofSalmonella typhimurium and 343 primo-isolates ofSalmonella enteritidis was performed at our laboratory. In 1991,S. enteritidis (43.8%) outnumberedS. typhimurium (32.1%) as the most frequently isolated Salmonella. The age group distribution ofS. enteritidis yielded peaks in the under-five and above-60 year age groups, whereasS. typhimurium only peaked in the under-five age group.S. enteritidis appeared to be twice as invasive asS. typhimurium. Both serotypes were more invasive in middle and older age groups than in under-fives.  相似文献   
95.
We compared three different microsurgical vasovasostomy techniques on the rat vas deferens using absorbable and non-absorbable sutures and a fibrin adhesive technique. The best method was an extramucosal technique over a splint using vicryl. The worst results were seen using adhesive.  相似文献   
96.
OBJECTIVES: Leakage around retrograde fillings is an important cause of endodontic surgery. This in vitro study sought to compare the following: (1) methylene blue dye leakage linked to retrofillings in human and sheep teeth with the degree of dye penetration when intermediate restorative materials and Chemfil were used as retrofillings, (2) the apical microleakage in filled with that in unfilled root canals, and (3) 2 storage techniques, incubator-based and subcutaneous implantation in rats. STUDY DESIGN: Tested were 198 human and 196 sheep teeth that were retrofilled with intermediate restorative material or Chemfil, then stored in an incubator or subcutaneously in rats for 10, 20, and 30 days before immersion in methylene blue dye for 24 hours. Linear dye penetration was evaluated, and the results were statistically analyzed by means of analysis of variance. RESULTS: Leakage between sheep and human teeth was significantly different (P <.05). Chemfil had significantly less leakage than intermediate restorative material after storage in rat (P <.05) for up to 20 days, but not after 30 days. No differences were found between leakage of unfilled and filled human root canal teeth. CONCLUSIONS: The sheep incisor is a poor experimental model of the human tooth, and both aging procedures demonstrate extensive leakage of retrofilling materials after long-term storage.  相似文献   
97.
Human ehrlichiosis is a recently recognized rickettsial disease. It is caused byEhrlichia chaffeensis, an intraleucocytic Gram-negative, obligate intracellular bacterium, grouped within the genusEhrlichiae. Most human cases of ehrlichiosis have been diagnosed in the USA. Two cases have been reported outside of the USA, one in Europe and one in Africa. From 1 January to 30 June 1992, 765 sera from blood donors or other asymptomatic subjects in 8 African countries, including Ivory Coast, Burkina Faso, Mali, Central African Republic, Angola, Zimbabwe, Mozambique and Commores Islands, were tested by indirect immunofluorescence for the presence ofE. chaffeensis antibodies. Positive sera were confirmed by Western immunoblotting. Only two of 765 sera tested were positive. One serum obtained from Burkina Faso had an IgG titer of 1:200 and one from Mozambique had an IgG titer of 1:80. Human ehrlichiosis seems to occur infrequently in Africa, although many more sera from additional African countries need to be evaluated.  相似文献   
98.
Obesity in youth and middle age and risk of colorectal cancer in men   总被引:5,自引:0,他引:5  
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services.  相似文献   
99.
We report the case of a child presenting with abdominal Burkitt's lymphoma in whom a relapse presented as orbital and muscle involvement. This clinical feature is extremely rare. Two muscle and one orbital biopsies were necessary to obtain proper diagnosis. A new extension check-up showed bone marrow invasion and normal cerebrospinal fluid. This relapse was successfully treated by conventional chemotherapy and consolidated with high-dose chemotherapy, total body irradiation and autologous bone marrow transplantation. Eighteen months after transplantation, the child may be considered as definitively cured.  相似文献   
100.
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