首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   97篇
  免费   5篇
儿科学   5篇
妇产科学   2篇
基础医学   6篇
口腔科学   3篇
临床医学   7篇
内科学   25篇
皮肤病学   2篇
神经病学   5篇
特种医学   9篇
外科学   17篇
综合类   10篇
预防医学   3篇
眼科学   1篇
药学   1篇
肿瘤学   6篇
  2024年   1篇
  2023年   1篇
  2022年   1篇
  2021年   4篇
  2018年   6篇
  2017年   2篇
  2016年   1篇
  2015年   1篇
  2014年   5篇
  2013年   4篇
  2012年   5篇
  2011年   7篇
  2010年   4篇
  2009年   2篇
  2008年   2篇
  2007年   5篇
  2006年   5篇
  2005年   4篇
  2004年   2篇
  2003年   3篇
  2002年   1篇
  1999年   1篇
  1998年   3篇
  1997年   9篇
  1996年   4篇
  1995年   2篇
  1994年   2篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1989年   1篇
  1988年   2篇
  1987年   3篇
  1986年   1篇
  1985年   2篇
  1982年   1篇
  1981年   1篇
  1976年   1篇
排序方式: 共有102条查询结果,搜索用时 15 毫秒
81.

Aims

The laparoscopic approach to tumour nephrectomy in children is controversial. We therefore reviewed our institution's cases of tumour nephrectomy (laparoscopic, open, and converted) to better understand which is suitable for this approach, what factors prevent it, and whether one can excise tumours greater than the CCLG recommendation of 300 ml.

Methods

All tumour nephrectomies performed between 2002 and 2016 were identified using our surgical database. Further data were gathered from radiology and pathology databases. Those with nonrenal tumours or having a partial nephrectomy were excluded. Tumour maximum diameters, volumes, and ratios to contralateral kidneys were calculated. A Mann–Whitney U was used to compare the groups.

Results

Forty-three cases were included. Fifteen procedures were completed laparoscopically (35%), and a further 3 converted. The median age at surgery was 2.5 years (range 0–10) in the laparoscopic group and 2 years (range 0–15) in the open group. There was a significant difference (P < 0.05) between the laparoscopic and open groups for: median maximum diameter (10cm vs 12.25cm), median volume (155 ml vs 459 ml), maximum diameter ratio (1.22 vs 1.75), and volume ratio (3.8 vs 11.2).

Conclusion

Tumours in the laparoscopic group were significantly smaller, but it was possible to excise tumours more than 300 ml. Difficulties in excision related to tumour size relative to the abdomen. Therefore, a ratio of tumour to contralateral kidney may be a better guide to safe excision than an overall volume cutoff. From our series, the laparoscopic approach is likely to be achievable if the volume ratio is ≤ 8.1.

Level of evidence

Level 3.  相似文献   
82.
Hypercalciuria of intestinal origin has been linked with bone loss in calcium nephrolithiasis and idiopathic osteoporosis. This retrospective data analysis was performed to explore potential pathogenetic link between intestinal hyperabsorption of calcium and postmenopausal osteoporosis. Data were retrieved from postmenopausal women who were evaluated for osteoporosis or osteopenia at the Mineral Metabolism Clinic of UT Southwestern Medical Center. A total of 319 patients underwent the test of calciuric response to oral calcium load to obtain an indirect measure of intestinal calcium absorption. Serum and urinary biochemistry and L2–L4 bone mineral density (BMD) were compared between five quintiles of calciuric response. There was a statistically significant trend toward a rise in 24-h urinary calcium and a decrease in urinary deoxypyridinoline (DPD) and BMD, with increasing order of quintiles. The presentation of those in the 1st quintile was consistent with vitamin D insufficiency or deficiency, with impaired calcium absorption, secondary hyperparathyroidism, and stimulated bone turnover (high normal urinary DPD). In contrast, patients in the 5th quintile displayed a picture of absorptive hypercalciuria of stone disease, with intestinal hyperabsorption of calcium, high or high normal urinary calcium and suppressed bone turnover (low or low normal urinary DPD). Thus, the assessment of intestinal calcium absorption in a seemingly homogeneous group of postmenopausal women with osteoporosis or osteopenia revealed a spectrum of calciuric response whose extremes may represent two physiologically distinct subtypes that have important diagnostic and therapeutic implications.  相似文献   
83.
84.
85.
86.
Long-term fluoride therapy for osteoporosis has been shown to increase the thickness of vertebral trabeculae as seen on spinal radiographs. To determine if this qualitative finding represents a measurable increase in spinal bone density, quantitative computed tomography was utilized to measure trabecular vertebral body density (TVBD) in the lumbar spine of 18 female osteoporotic patients, all of whom had been treated with sodium fluoride, 77 +/- 13 mg/day (mean +/- SD), and calcium, 1000 mg/day, for 57 +/- 24 months. TVBD in these fluoride treated osteoporotic patients (132 +/- 82 mg/cm3) was found to be significantly greater than mean TVBD for an age-matched group of untreated female osteoporotic patients (51 +/- 21 mg/cm3, n = 89, p less than 0.001). The value for TVBD in the long-term fluoride treated osteoporotics was not only similar to previously published values for TVBD (104 +/- 30 mg cm3) in normal females of similar age, but was also above the calculated TVBD "fracture threshold" of 100 mg/cm3 for females. Only one of the 18 fluoride treated osteoporotics continued to have spinal fractures during therapy, accounting for 4 fractures per 87.2 patient years of observation, a value which is significantly lower than the published incidence of 76 fractures per 91 patient years for untreated osteoporotic patients (p less than 0.001). Together, these findings demonstrate that long-term fluoride and calcium therapy for osteoporosis increases TVBD in the majority of patients within a reasonable time frame and significantly reduces the risk for spinal fractures.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
87.
To estimate the prevalence of toxoplasma antibodies in schoolchildren and their association with clinical and environmental data, antibody titres were measured in 1276 children aged 4 to 18 years attending primary and secondary schools. Environmental and clinical data were obtained by questionnaire. Altogether 12.8% (163/1276) of children had antibodies to Toxoplasma gondii with no difference between the sexes. Seroprevalence was higher in country children (16.6% (50/302)) than town children (10.2% (75/737)). The proportion testing positive increased with age in both town and country children. No association with cat ownership was found. Toxoplasma seropositivity was associated with a positive toxocara titre, having had a bitch whelp in the past two years, and having an unwormed dog at home. Lack of energy or tiredness in the last 12 months were the only clinical features associated with a positive titre.  相似文献   
88.
Rao  CV; Chou  D; Simi  B; Ku  H; Reddy  BS 《Carcinogenesis》1998,19(10):1815-1819
The present experiments were aimed at developing novel dietary fibers to aid in reduction of colon cancer risk. We assessed the effects of coffee (non-fiber fraction), coffee fiber (arabino-galactose polymer) and inulin (oligo-fructose) in male F344 rats using formation of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in the colon as the measure of preventive efficacy (or lack of such). At 5 weeks of age, groups of rats were fed the AIN-76A (control) and experimental diets that contained 1% coffee, 10% coffee fiber, 10% inulin, 10% pectin (positive control for fiber) or 200 p.p.m. piroxicam (a known ACF inhibitor). At 7 weeks of age, all animals were s.c injected with AOM (15 mg/kg body wt) once weekly for 2 weeks. All rats were killed 8 weeks after the last AOM injection and ACF were counted. The contents of the cecum were analyzed for bacterial beta-glucuronidase activity and short-chain fatty acids (SCFAs). Dietary administration of coffee fiber significantly suppressed AOM-induction of colonic ACF, in terms of total number, as well as crypt multiplicity and number of ACF/cm2 colon (P < 0.01-0.001). Inulin diet had no significant effect on total ACF, but had reduced the number of ACF/cm2 (P < 0.05). Whereas coffee had no effect on ACF formation, 10% pectin diet and 200 p.p.m. piroxicam significantly suppressed colonic ACF (P < 0.001) as had been expected. A significant reduction of cecal beta-glucuronidase activity was observed in the rats fed coffee, coffee fiber and pectin diets. Further, coffee fiber, inulin and pectin increased cecal SCFA levels 3- to 5-fold. These results suggest that coffee fiber can prevent colon cancer risk. Further studies are warranted to determine the full potential of this fiber in pre-clinical efficacy studies.   相似文献   
89.
OBJECTIVE: To assess the natural history of respiratory symptoms not labelled as asthma in primary schoolchildren. DESIGN: Repeat questionnaire survey of subgroups identified from a previous questionnaire survey after a two year delay. SUBJECTS: The original population of 5321 Sheffield children aged 8-9 years yielded 4406 completed questionnaires in 1991(82.8%). After excluding children with a label of asthma, there were 370 children with current wheeze, 129 children with frequent nocturnal cough, and a random sample of 222 children with minor cough symptoms and 124 asymptomatic children. RESULTS: Response rates in the four groups were 233 (63.0%), 77 (59.7%), 160 (72.1%), and 90 (72.6%) respectively. Of those who initially wheezed, 114 (48.9%) had stopped wheezing and 42 (18.0%) had been labelled as having asthma. Those with more frequent wheezing episodes (p < 0.02) and a personal history of hay fever (p < 0.01) in 1991 were more likely to retain their wheezy symptoms. In the children with frequent nocturnal cough in 1991, 20.1% had developed wheezing, 42.9% had a reduced frequency of nocturnal coughing, and 14.2% had stopped coughing altogether two years later. One sixth had been labelled as having asthma. Children with nocturnal cough were more likely to develop wheezing if they had a family history of atopy (p = 0.02). Only 3.8% and 3.3% of those with minimal cough and no symptoms respectively in 1991 had developed wheeze by 1993 (1.9% and 1.0% labelled as asthma). CONCLUSIONS: Most unlabelled recurrent respiratory symptoms in 8-10 year olds tend to improve. Unlabelled children who have persistent symptoms have other features such as frequent wheezing attacks and a family or personal history of atopy. If a screening questionnaire were to be used to identify such children, a combination of questions should be employed.  相似文献   
90.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号