全文获取类型
收费全文 | 19850篇 |
免费 | 1635篇 |
国内免费 | 89篇 |
专业分类
耳鼻咽喉 | 250篇 |
儿科学 | 572篇 |
妇产科学 | 316篇 |
基础医学 | 2497篇 |
口腔科学 | 293篇 |
临床医学 | 2116篇 |
内科学 | 4905篇 |
皮肤病学 | 287篇 |
神经病学 | 1442篇 |
特种医学 | 715篇 |
外科学 | 3258篇 |
综合类 | 278篇 |
一般理论 | 9篇 |
预防医学 | 1336篇 |
眼科学 | 738篇 |
药学 | 1184篇 |
中国医学 | 54篇 |
肿瘤学 | 1324篇 |
出版年
2023年 | 95篇 |
2022年 | 153篇 |
2021年 | 323篇 |
2020年 | 201篇 |
2019年 | 381篇 |
2018年 | 412篇 |
2017年 | 325篇 |
2016年 | 321篇 |
2015年 | 358篇 |
2014年 | 543篇 |
2013年 | 834篇 |
2012年 | 1186篇 |
2011年 | 1163篇 |
2010年 | 702篇 |
2009年 | 697篇 |
2008年 | 1160篇 |
2007年 | 1217篇 |
2006年 | 1240篇 |
2005年 | 1160篇 |
2004年 | 1131篇 |
2003年 | 1076篇 |
2002年 | 1017篇 |
2001年 | 337篇 |
2000年 | 333篇 |
1999年 | 295篇 |
1998年 | 215篇 |
1997年 | 201篇 |
1996年 | 165篇 |
1995年 | 204篇 |
1994年 | 160篇 |
1993年 | 137篇 |
1992年 | 250篇 |
1991年 | 202篇 |
1990年 | 197篇 |
1989年 | 181篇 |
1988年 | 186篇 |
1987年 | 184篇 |
1986年 | 167篇 |
1985年 | 146篇 |
1984年 | 146篇 |
1983年 | 151篇 |
1982年 | 142篇 |
1981年 | 132篇 |
1980年 | 127篇 |
1979年 | 117篇 |
1978年 | 108篇 |
1977年 | 117篇 |
1976年 | 91篇 |
1975年 | 63篇 |
1974年 | 86篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
Monitoring the protective effects of minocycline treatment with radiolabeled annexin V in an experimental model of focal cerebral ischemia. 总被引:3,自引:0,他引:3
Xian Nan Tang Qing Wang Maya A Koike Danye Cheng Michael L Goris Francis G Blankenberg Midori A Yenari 《Journal of nuclear medicine》2007,48(11):1822-1828
Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia. 相似文献
73.
Bruno Fautrel Thao Pham Gaël Mouterde Xavier Le Loët Philippe Goupille Francis Guillemin Philippe Ravaud Alain Cantagrel Maxime Dougados Xavier Puchal Jean Sibilia Martin Soubrier Xavier Mariette Bernard Combe pour le Club rhumatismes et inflammation pour la Socit franaise de rhumatologie 《Revue du Rhumatisme》2007,74(12):1301-1311
74.
Prophylactic laparoscopic-assisted total gastrectomy for hereditary diffuse gastric cancer. 总被引:2,自引:0,他引:2
Wesley P Francis Daniald M Rodrigues Nolan E Perez Fulvio Lonardo Donald Weaver John D Webber 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(1):142-147
BACKGROUND: Ten percent of gastric cancer (GC) cases are familial, with one third resulting from a mutation in the tumor suppressor gene CDH1. Loss of this important structure can result in hereditary diffuse gastric cancer (HDGC), which carries a high mortality if early diagnosis is not made. Despite its clear genetic origin, optimal management of HDGC family members is controversial, as the utility and efficacy of current cancer screening programs for mutation carriers are unproven. METHODS: A 53-year-old Caucasian woman was initially seen for genetic screening because multiple family members had mutations of the CDH1 gene. Her pedigree analysis demonstrated 4 generations of gastric cancer, and 2 of the generations carried the CDH1 germline mutation, consistent with HDGC. At endoscopy, the patient's gastric mucosa was normal and random biopsies were also normal. The patient underwent a laparoscopic total gastrectomy. RESULTS: The gross examination of her stomach appeared normal. On histologic examination, however, the stomach was found to have diffuse (signet ring cell) adenocarcinoma in-situ with 11 microscopic foci of invasive adenocarcinoma limited to the lamina propria. CONCLUSION: Our case is the first reported prophylactic total gastrectomy utilizing a laparoscopic approach, and it highlights the importance of taking a thorough family history and obtaining a pedigree analysis. Endoscopic screening in HDGC cannot rule out diffuse GC, because the stomach and biopsies can be normal despite the presence of adenocarcinoma. Therefore, our case supports the recommendation for prophylactic gastrectomy in HDGC. 相似文献
75.
Dinesh Singh Ajit K. Banerji Bilikere S. Dwarakanath Rajendra P. Tripathi Jaganath P. Gupta T. Lazar Mathew Turuga Ravindranath Viney Jain 《Strahlentherapie und Onkologie》2005,355(1):507-514
Background and Purpose:
Higher rates of glucose utilization and glycolysis generally correlate with poor prognosis in several types of malignant tumors. Own earlier studies on model systems demonstrated that the nonmetabolizable glucose analog 2-deoxy-D-glucose (2-DG) could enhance the efficacy of radiotherapy in a dose-dependent manner by selectively sensitizing cancer cells while protecting normal cells. Phase I/II clinical trials indicated that the combination of 2-DG, at an oral dose of 200 mg/kg body weight (BW), with large fractions of γ-radiation was well tolerated in cerebral glioma patients. Since higher 2-DG doses are expected to improve the therapeutic gain, present studies were undertaken to examine the tolerance and safety of escalating 2-DG dose during combined treatment (2-DG + radiotherapy) in glioblastoma multiforme patients. 相似文献76.
Psychosocial factors at work and perceived health among agricultural meat industry workers in France
Christine Cohidon Patrick Morisseau Francis Derriennic Marcel Goldberg Ellen Imbernon 《International archives of occupational and environmental health》2009,82(7):807-818
Objective The objective of this study was to describe the perceived health status of the meat industry employees—i.e., working in the
slaughtering, cutting, and boning of large animals and poultry—and its relation to their organisational and psychosocial constraints
at work.
Methods This postal survey included all 3,000 employees of the meat industry (beef, pork and poultry) in four districts in Brittany,
France, whose companies were affiliated with the agricultural branch of the national health insurance fund. The questionnaire
asked for social and demographic data and information describing their job and the organisation of their work. The psychosocial
factors at work were described according to Karasek’s questionnaire (demand, latitude and social support at work). Perceived
health was measured with the Nottingham Health Profile perceived health indicator.
Results This study shows the high prevalence of poor health reported by the workers in this industry. This poor perceived health was
worse in women and increased regularly with age. Among the psychosocial factors studied, high quantitative and qualitative
demand at work, inadequate resources for good work and to a lesser extent, inadequate prospects for promotion appear especially
associated with poor perceived health. Other factors often associated with poor perceived health included young age at the
first job and work hours that disrupt sleep rhythms (especially for women).
Conclusion Our results show that this population of workers is especially vulnerable from the point of view of perceived physical and
psychological health and is exposed to strong physical, organisational and psychosocial constraints at work. They also demonstrate
that poor perceived health is associated with some psychosocial (such as high psychological demand and insufficient resources)
and organisational factors at work. These results, in conjunction with those from other disciplines involved in studying this
industry, may help the companies to develop preventive activities. 相似文献
77.
78.
A N Nicolaides S K Kakkos M Griffin M Sabetai S Dhanjil T Tegos D J Thomas A Giannoukas G Geroulakos N Georgiou S Francis E Ioannidou C J Doré 《European journal of vascular and endovascular surgery》2005,30(3):275-284
OBJECTIVES: This study determines the risk of ipsilateral ischaemic neurological events in relation to the degree of asymptomatic carotid stenosis and other risk factors. METHODS: Patients (n=1115) with asymptomatic internal carotid artery (ICA) stenosis greater than 50% in relation to the bulb diameter were followed up for a period of 6-84 (mean 37.1) months. Stenosis was graded using duplex, and clinical and biochemical risk factors were recorded. RESULTS: The relationship between ICA stenosis and event rate is linear when stenosis is expressed by the ECST method, but S-shaped if expressed by the NASCET method. In addition to the ECST grade of stenosis (RR 1.6; 95% CI 1.21-2.15), history of contralateral TIAs (RR 3.0; 95% CI 1.90-4.73) and creatinine in excess of 85 micromol/L (RR 2.1; 95% CI 1.23-3.65) were independent risk predictors. The combination of these three risk factors can identify a high-risk group (7.3% annual event rate and 4.3% annual stroke rate) and a low risk group (2.3% annual event rate and 0.7% annual stroke rate). CONCLUSIONS: Linearity between ECST per cent stenosis and risk makes this method for grading stenosis more amenable to risk prediction without any transformation not only in clinical practice but also when multivariable analysis is to be used. Identification of additional risk factors provides a new approach to risk stratification and should help refine the indications for carotid endarterectomy. 相似文献
79.
Isabelle Legroux-Gerot Jean Vignau Francis Collier Bernard Cortet 《Revue du Rhumatisme》2005,72(12):1256-1262
The objective of this study was to evaluate the epidemiology, diagnosis, pathophysiology, and treatment of bone loss related to anorexia nervosa. Earlier onset and longer duration of anorexia nervosa are associated with more severe bone loss. Osteoporosis develops in 38 to 50% of cases. Bone mineral density measurement by dual-energy X-ray absorptiometry is useful for assessing bone mass, and bone marker assays provide information on bone turnover. Bone loss in anorexia nervosa is probably multifactoriel. Estrogen deficiency was long felt to be the major factor. However, in contrast to postmenopausal osteoporosis, bone loss associated with anorexia nervosa is related mainly to inadequate bone formation, with only a slight increase in bone resorption. This suggests a role for nutritional factors, such as disturbances in the growth hormone-somatomedin C axis (GH/IGF-I) related to malnutrition. The best treatment strategy for correcting bone mass in patients with anorexia nervosa is not agreed on. Resumption of menstrual cycles and weight gain seem necessary but not always sufficient. Studies found no benefits with estrogen therapy, but this was usually given as estrogen–progestin contraceptives. No vast studies evaluating hormone replacement therapy have been reported. Bone formation enhancers such as IGF-I seem to provide the best results, most notably when used in combination with estrogens. This suggests that complex treatment strategies combining bone formation enhancers and bone resorption inhibitors may deserve evaluation. 相似文献
80.