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   203篇
  免费   4篇
  国内免费   1篇
耳鼻咽喉   2篇
儿科学   8篇
妇产科学   4篇
基础医学   10篇
口腔科学   1篇
临床医学   12篇
内科学   30篇
皮肤病学   3篇
神经病学   13篇
特种医学   8篇
外科学   82篇
综合类   4篇
预防医学   8篇
眼科学   9篇
药学   6篇
肿瘤学   8篇
  2024年   1篇
  2022年   4篇
  2021年   4篇
  2020年   3篇
  2019年   4篇
  2018年   1篇
  2017年   1篇
  2016年   6篇
  2015年   8篇
  2014年   7篇
  2013年   9篇
  2012年   8篇
  2011年   11篇
  2010年   7篇
  2009年   5篇
  2008年   8篇
  2007年   2篇
  2006年   16篇
  2005年   22篇
  2004年   23篇
  2003年   25篇
  2002年   13篇
  2001年   3篇
  2000年   2篇
  1999年   1篇
  1998年   1篇
  1997年   2篇
  1996年   1篇
  1994年   1篇
  1992年   1篇
  1990年   1篇
  1988年   2篇
  1987年   3篇
  1986年   1篇
  1969年   1篇
排序方式: 共有208条查询结果,搜索用时 15 毫秒
1.
Summary The excretion of thioethers was determined in the urine of workers involved in road paving operations and in the preparation of asphalt mixing in an asphalt plant. An occupationally nonexposed group served as control. From the results it was observed that there was no significant difference in urinary thioether levels between the exposed and nonexposed groups, however, smokers of both exposed groups had significantly higher urinary thioether levels than the nonexposed smoking workers. These results suggested that higher urinary thioether excretion could be only due to a difference in smoking behaviour. There were also significant differences in urinary thioether levels between the exposed smoking and nonsmoking workers. The authors suggest that these workers have a low mutagenic/carcinogenic risk and smoking is responsible for the majority of thioether excretion, as has been found by other investigators.  相似文献   
2.
Methods: Second primary cancers constitute approximately 9–10% of malignancies diagnosed in the United States. We aimed to show the risk and incidance of second primary tumor occuring associated to urologic tumors and show the distrubution of tumors in Tracia region. We retrospectively examined the patients' files with the diagnosis of malignant disease between the years 1985–2000. Hazard function analysis was performed to estimate the relative risk of secondary malignancy occuring. Age, sex and tumor number were examined to find out if they affect on mortality rate. Results: A total number of 25 MPMNs were diagnosed. In 52 percent of the cases the second primary neoplasm developed within six months. The relative risk of development of a second neoplasm is found as increasing 1.111 times per month. The incidence of secondary malignancy occuring in the patients with one tumor was found as 6.31%. Age (p < 0.001) and tumor number (p < 0.001) are found as statistically effective predictor on mortality rate where the sex is not. Conclusions: In the patients with a primary tumor not only the metastasis must be investigated but also second primary tumors should be taken in to consideration. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
3.
4.
The peroxisome proliferator-activated receptor gamma (PPAR gamma) is a critical regulator of adipogenesis. PPAR gamma+/- mice are resistant to high-fat diet-induced obesity and thus PPAR gamma may mediate physiological responses to dietary fat in other mammals. The aim of this study was to determine whether the human PPAR gamma proline to alanine substitution polymorphism (Pro12Ala) modifies the association between dietary fat and adiposity and plasma lipids. Subjects (n=2141) were controls selected for three case-control studies nested within the Nurses' Health Study, a large ongoing prospective cohort study. Associations between intake of total fat, fat subtypes and BMI were different in PPAR gamma 12Ala variant allele-carriers compared with non-carriers. Among homozygous wild-type Pro/Pro individuals, those in the highest quintile of total fat intake, had significantly higher mean body mass index (BMI) compared with those in the lowest quintile (27.3 versus 25.4 kg/m2, respectively; P-trend<0.0001) whereas among 12Ala variant allele-carriers there was no significant trend observed between dietary fat intake and BMI (P-trend=0.99; P-interaction=0.003). In contrast, intake of monounsaturated fat was not associated with BMI among homozygous wild-type women but was inversely associated with BMI among 12Ala variant allele-carriers (mean in lowest quintile=27.6 versus mean in highest quintile=25.5 kg/m2; P-trend=0.006; P-interaction=0.003). The relationship between dietary fat intake and plasma lipid concentrations also differed according to PPAR gamma genotype. These data suggest that PPAR gamma genotype is an important factor in physiological responses to dietary fat in humans.  相似文献   
5.
6.
7.
Previous studies showed oxidative stress had an important impact on osteoclastic and osteoblastic functions. Oxidative stress or low levels of antioxidants are supposed to reduce BMD and cause osteoporosis. hcy, gamma glutamyltransferase (GGT), uric acid, albumin and total bilirubin are simple laboratory parameters that are related with oxidative stress. In this study we compare the serum hcy and antioxidant levels in patients with osteoporosis, osteopenia and control subjects. A total of 2190 elderly persons (1348 patients with osteoporosis, 643 patients with osteopenia and 199 control subjects) who were referred to the outpatient clinic of the Department of Internal Medicine, Division of Geriatric Medicine at Hacettepe University Hospital for comprehensive geriatric assessment were included in this cross-sectional study. Mean age of subjects were 72.30±6.34 in osteoporosis group, 71.92±6.90 in osteopenia and 71.86±5.88 in control group (p: 0.260). Multivariate regression analysis revealed that hypertension (HT) (OR: 0.675, 95% CI: 0.534-0.854, p: 0.001), diabetes mellitus (DM) (OR: 1.669, 95% CI: 1.301-2.142, p: <0.001), age (OR: 1.025, 95% CI: 1.006-1.044, p: 0.009), male gender (OR: 0.451, 95% CI: 0.358-0.569, p<0.001), uric acid (OR: 0.893, 95% CI: 0.837-0.952, p: 0.001), hcy (OR: 1.042, 95% CI: 1.023-1.061, p<0.001), albumin (OR: 0.521, 95% CI: 0.376-0.724, p<0.001), GGT (OR: 1.010, 95% CI: 1.003-1.017, p: 0.003), creatinine (OR: 0.630, 95% CI: 0.459-0.864, p: 0.004) were independent variables predicting the occurrence of osteoporosis. This study shows there is an imbalance between natural antioxidative and oxidative markers in patients with osteoporosis. Higher serum uric acid and albumin levels are associated with a lower prevalence of osteoporosis whereas higher hcy and GGT levels are associated lower BMD and higher osteoporosis prevalence.  相似文献   
8.
Aim: Urinary stone disease affects people of all ages. With its satisfactory efficacy ranges in all age groups and lack of side‐effects, extracorporeal shock wave lithotripsy (ESWL) has become the preferred treatment modality for uncomplicated renal and proximal calculi ≤20 mm. In the present study, we aimed to assess the safety and efficacy of the ESWL treatment in elderly patients. Methods: A retrospective study was carried out on patients aged over 65 years who underwent shock wave lithotripsy at our Department from 2009 to 2011, with a Siemens Lithostar electromagnetic shockwave lithotripter. A total of 231 patients (157 males, 74 females) out of 1694 (13.6%) were studied. The patients were divided into two groups (group 1 = 65–70; group 2 >70). The effect of age and other possible predicting factors (sex, stone localization and stone size) were investigated. Concomitant diseases and related complications were also evaluated. Results: An overall stone‐free rate (SFR) of 82.2% was found. The influence of sex on SFR was non‐significant. There was no significant difference when comparing SFR between the age groups. When patients were divided into those with renal and ureteral stones, the SFR were 94.4% and 67.6% (P < 0.01), respectively. The SFR of the stone size groups, ≤10 mm and >10 mm were 80% and 84.4%, respectively. Comorbidity was present in 148 patients. Complications were noted in 56 of 231 patients. Of 56 patients, 43 had minor complications and 13 major complications. Conclusion: ESWL seems to be an effective first‐line treatment choice for urinary stones in elderly patients with careful patient selection and personalized preparation. Geriatr Gerontol Int 2012; 12: 413–417.  相似文献   
9.
Calcaneal fractures are very common injuries, and closed reduction-percutaneous pinning, open reduction-internal fixation, and primary arthrodesis are the procedures used in the surgical treatment of these injuries. The aim of surgical treatment is to restore the normal biomechanics of the Achilles tendon and rearfoot by anatomic reduction of the articular surfaces. Minimization of the soft tissue complications commonly associated with the open treatment of calcaneal fractures can be achieved using indirect closed reduction and Kirschner wire or screw-assisted minimally invasive percutaneous osteosynthesis methods. In the present report, we describe a technique for the treatment of calcaneal fractures associated with soft tissues that are at risk of complications and present the cases of 3 patients treated with indirect, minimally invasive reduction of comminuted calcaneal fractures with the Endobutton® fixation device. From our experience with this method, we believe it will be useful in cases of acute calcaneal fracture with pronounced soft tissue injury localized to the hindfoot.  相似文献   
10.
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