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81.
An analysis of all early onset neonatal Group B streptococcal (GBS) infections at the Royal Women's Hospital, Melbourne was made for the 10-year period 1979-1988. There were 104 cases with 29 neonatal deaths (28%). One or more predisposing perinatal risk factors was evident in 82% of cases (premature labour 79%, prolonged membrane rupture (greater than 12 hours) 57%, premature rupture of the membranes 69%, maternal sepsis 29%). Overall, 88% of GBS infections were evident within 24 hours of birth, suggesting an intrapartum pathogenesis for infection.  相似文献   
82.
We reviewed charts of 261 children seen at Children's Hospital of Wisconsin from 1957 to 1987 with culture-proven meningococcemia or meningococcal meningitis, and we analyzed trends in mortality and disease severity for that interval. Overall case fatality was 10%, ranging from 9% in the period 1957 to 1963, to 16% in the period 1980 to 1987 (P = 0.15). The percent of patients admitted with severe disease increased from 14% to 38% (P = 0.001). When stratified by disease severity, case-fatality rates did not change with time. We conclude that technologic advances of the past 30 years had no measurable impact on mortality from meningococcal infection in our hospital and that crude case-fatality rates can be misleading if disease severity is not considered.  相似文献   
83.
One hundred fifty-five inborn infants with a birth weight <- 1,500 gm were prospectively evaluated for germinal layer/intraventricular hemorrhage. Maternal characteristics, obstetric factors, and neonatal condition in the immediate newborn period were analyzed as possible risk factors for germinal layer/intraventricular hemorrhage. Early germinal layer/intraventricular hemorrhage or hemorrhages identified during the first 24 hours of life were observed in 85 (55%) of these infants. Another 37 (24%) had germinal layer/intraventricular hemorrhage after 24 hours of age (late germinal layer/intraventricular hemorrhage). None of the maternal and obstetric variables, including labor, mode of delivery, and presentation, appeared to increase the risk of germinal layer/intraventricular hemorrhage. The immediate neonatal condition, birth weight, gestational age, and intrauterine growth, all influenced the occurrence of germinal layer/intraventricular hemorrhage, especially early germinal layer/intraventricular hemorrhage. We suggest that future studies to investigate the role of maternal or obstetric factors in the pathogenesis of germinal layer/intraventricular hemorrhage should discriminate early from late germinal layer/intraventricular hemorrhage. Obstetric factors are more likely to influence the early onset of germinal layer/intraventricular hemorrhage; their effect, if any, becomes less discernible later.  相似文献   
84.
Physical activity, body mass index, and ovulatory disorder infertility   总被引:12,自引:0,他引:12  
Few studies have examined whether activity and adiposity levels typical of American women affect their risk of ovulatory disorder infertility, and none has examined moderate and vigorous intensity exercise separately. We investigated these associations in the Nurses' Health Study II, comparing prospectively collected data on adiposity and activity for 830 cases of incident ovulatory infertility and 26,125 pregnancies. We observed a U-shaped association between body mass index (BMI) and relative risk of ovulatory infertility, with increased risk for BMI below 20.0 or above 24.0 kg/m2. On the basis of the BMI distribution of U.S. women, these findings suggest that 12% (95% confidence interval = 7-20%) of ovulatory infertility in the U.S. may be attributable to underweight (BMI <20.0) and 25% (95% CI = 20-31%) to overweight (BMI > or = 25.0). An increase in vigorous activity (but not moderate activity) was associated with reduced relative risk of ovulatory infertility. Each hour per week of vigorous activity was associated with a 7% (95% CI = 4-10%) lower relative risk of ovulatory infertility. After adjustment for BMI, a 5% (95% CI = 2-8%) reduction in relative risk per hour of weekly activity remained. These data suggest that, among American women, more ovulatory infertility is attributable to overweight and a sedentary lifestyle than to underweight and overexertion.  相似文献   
85.
86.
目的 探讨速溶山楂饮料调节高脂血症患者脂质紊乱、提高抗氧化酶活力和增强免疫功能的作用。方法  6 0名年龄 (5 7 9± 8 0 )岁高脂血症受试者 ,采用交叉试验方案 ,每名受试者参加 2次试验。半数受试者于第 1次试验补充速溶山楂饮料 (含 3g山楂干粉、相当于 30g鲜果 ,溶于 10 0ml水及饮料载体 ,1d 2次 ) ,另半数补充对照液 (0 75g瓜儿胶和少量淀粉作为饮料载体 ,1d 2次 )。持续 31d ,间隔 2 8d后 ,开始第 2次试验 ,受试者原补充速溶山楂饮料者 ,改为对照 ;原补充对照改为速溶山楂饮料。结果 补充速溶山楂饮料能显著降低血清总胆固醇 (9 6 % )、甘油三酯 (12 1% )、低密度脂蛋白 (18% ) ;而明显增加超氧化物歧化酶 (SOD)活力 (7 5 % )水平。受试者补充含瓜儿胶对照液虽然对某些血清脂质也有一定的改善作用 ,但效果不如速溶山楂饮料显著 ;而且 ,受试者仅在补充速溶山楂饮料时血清甘油三酯水平显著降低、抗氧化酶SOD水平显著提高 ,补充对照液无作用。结论 补充速溶山楂饮料能有效降低血清总胆固醇、甘油三酯、低密度脂蛋白、丙二醛水平 ,升高ApoA Ⅰ水平、SOD活性和NK细胞活力 ;综合测试表明 :补充速溶山楂饮料和对照比 ,调整血脂、提高抗氧化酶活力效果更显著。  相似文献   
87.
Squamous cell carcinoma of the vulva is a disease of significant clinical importance, which arises in the presence or absence of human papillomavirus. We used comparative genomic hybridisation to document non-random chromosomal gains and losses within human papillomavirus positive and negative vulvar cancers. Gain of 3q was significantly more common in human papillomavirus-positive cancers compared to human papillomavirus-negative cancers. The smallest area of gain was 3q22-25, a chromosome region which is frequently gained in other human papillomavirus-related cancers. Chromosome 8q was more commonly gained in human papillomavirus-negative compared to human papillomavirus-positive cancers. 8q21 was the smallest region of gain, which has been identified in other, non-human papillomavirus-related cancers. Chromosome arms 3p and 11q were lost in both categories of vulvar cancer. This study has demonstrated chromosome locations important in the development of vulvar squamous cell carcinoma. Additionally, taken together with previous studies of human papillomavirus-positive cancers of other anogenital sites, the data indicate that one or more oncogenes important in the development and progression of human papillomavirus-induced carcinomas are located on 3q. The different genetic changes seen in human papillomavirus-positive and negative vulvar squamous cell carcinomas support the clinicopathological data indicating that these are different cancer types.  相似文献   
88.

Background  

In Ireland, 30% of non-fatal overdoses involve paracetamol.  相似文献   
89.
1. Commercially available nucleic acid amplification assays (eg, polymerase or ligase chain reaction) are now the "gold standard" tests for genital chlamydial infection and also have a role in screening for gonococcal infection. 2. Single-dose oral antibiotics are available for treatment of Chlamydia trachomatis, Neisseria gonorrhoeae and Trichomonas vaginalis infections. 3. Strains of N. gonorrhoeae in urban Australia are often penicillin resistant, while strains from South East Asia and those in homosexually active men may show high-level resistance to quinolones. 4. Imiquimod, a novel immune-response modifier, is now available for effective, safe, self-administered treatment of genital warts. 5. The Pap smear remains the cornerstone of screening for precursor lesions of cervical cancer, but human papillomavirus genotyping may have a role in clinical decision-making for women with equivocal or early precancerous lesions. 6. Treatment of primary genital herpes changes the clinical course, and long-term suppressive therapy is effective for those with multiple recurrences. New technologies have made diagnosis and screening easier for patients and clinicians  相似文献   
90.
Background: When attempting to interpret CT scans after radiofrequency thermal ablation (RFA) of liver tumors, it is sometimes difficult to distinguish ablated from viable tumor tissue. Identification of the two types of tissue is specially problematic for lesions that are hypodense before ablation. The aim of this study was to determine whether quantitative Hounsfield unit (HU) density measurements can be used to document the lack of tumor perfusion and thereby identify ablated tissue. Methods: Liver spiral CT scans of 13 patients with 51 lesions undergoing laparoscopic RFA for metastatic liver tumors within a 2-year time period were reviewed. HU density of the lesions as well as normal liver were measured pre- and postoperatively in each CT phase (noncontrast, arterial, portovenous). Statistical analyses were performed using Student's paired t-test and ANOVA. Results: Normal liver parenchyma, which was used as a control, showed a similar increase with contrast injection in both pre- and postprocedure CT scans (56.4 ± 2.4 vs 57.1 ± 2.4 HU, respectively; p= 0.3). In contrast, ablated liver lesions showed a preablation increase of 45.7 ± 3.4 HU but only a minimal postablation increase of 6.6 ± 0.7 HU (p < 0.0001). This was true for highly vascular tumors (neuroendocrine) as well as hypovascular ones (adenocarcinoma). Conclusions: This is the first study to define quantitative radiological criteria using HU density for the evaluation of ablated tissues. A lack of increase in HU density with contrast injection indicates necrotic tissue, whereas perfused tissue shows an increase in HU density. This technique can be used in the evaluation of patients undergoing RFA. Received: 1 March 2000/Accepted: 4 April 2000/Online publication: 9 August 2000  相似文献   
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