全文获取类型
收费全文 | 1699篇 |
免费 | 187篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 75篇 |
妇产科学 | 45篇 |
基础医学 | 215篇 |
口腔科学 | 36篇 |
临床医学 | 262篇 |
内科学 | 293篇 |
皮肤病学 | 31篇 |
神经病学 | 201篇 |
特种医学 | 157篇 |
外科学 | 149篇 |
综合类 | 121篇 |
预防医学 | 127篇 |
眼科学 | 14篇 |
药学 | 105篇 |
中国医学 | 1篇 |
肿瘤学 | 47篇 |
出版年
2021年 | 21篇 |
2020年 | 10篇 |
2019年 | 23篇 |
2018年 | 21篇 |
2017年 | 18篇 |
2016年 | 18篇 |
2015年 | 36篇 |
2014年 | 54篇 |
2013年 | 55篇 |
2012年 | 79篇 |
2011年 | 66篇 |
2010年 | 60篇 |
2009年 | 62篇 |
2008年 | 73篇 |
2007年 | 66篇 |
2006年 | 53篇 |
2005年 | 56篇 |
2004年 | 43篇 |
2003年 | 54篇 |
2002年 | 33篇 |
2001年 | 49篇 |
2000年 | 36篇 |
1999年 | 40篇 |
1998年 | 62篇 |
1997年 | 56篇 |
1996年 | 44篇 |
1995年 | 30篇 |
1994年 | 37篇 |
1993年 | 28篇 |
1992年 | 25篇 |
1991年 | 52篇 |
1990年 | 37篇 |
1989年 | 24篇 |
1988年 | 34篇 |
1987年 | 43篇 |
1986年 | 31篇 |
1985年 | 30篇 |
1984年 | 20篇 |
1983年 | 18篇 |
1982年 | 24篇 |
1981年 | 16篇 |
1980年 | 9篇 |
1979年 | 18篇 |
1978年 | 32篇 |
1977年 | 14篇 |
1976年 | 24篇 |
1975年 | 21篇 |
1974年 | 10篇 |
1972年 | 9篇 |
1967年 | 9篇 |
排序方式: 共有1901条查询结果,搜索用时 12 毫秒
71.
72.
Ji‐Jie Pang Zhuo Yang Roy A. Jacoby Samuel M. Wu 《The Journal of comparative neurology》2018,526(12):1896-1909
Some mammalian rod bipolar cells (RBCs) can receive excitatory chemical synaptic inputs from both rods and cones (DBCR2), but anatomical evidence for mammalian cone‐RBC contacts has been sparse. We examined anatomical cone‐RBC contacts using neurobiotin (NB) to visualize individual mouse cones and standard immuno‐markers to identify RBCs, cone pedicles and synapses in mouse and baboon retinas. Peanut agglutinin (PNA) stained the basal membrane of all cone pedicles, and mouse cones were positive for red/green (R/G)‐opsin, whereas baboon cones were positive for calbindin D‐28k. All synapses in the outer plexiform layer were labeled for synaptic vesicle protein 2 (SV2) and PSD (postsynaptic density)‐95, and those that coincided with PNA resided closest to bipolar cell somas. Cone‐RBC synaptic contacts were identified by: (a) RBC dendrites deeply invaginating into the center of cone pedicles (invaginating synapses), (b) RBC dendritic spines intruding into the surface of cone pedicles (superficial synapses), and (c) PKCα immunoreactivity coinciding with synaptic marker SV2, PSD‐95, mGluR6, G protein beta 5 or PNA at cone pedicles. One RBC could form 0‐1 invaginating and 1‐3 superficial contacts with cones. 20.7% and 38.9% of mouse RBCs contacted cones in the peripheral and central retina (p < .05, n = 14 samples), respectively, while 34.4% (peripheral) and 48.5% (central) of cones contacted RBCs (p > .05). In baboon retinas (n = 4 samples), cone‐RBC contacts involved 12.2% of RBCs (n = 416 cells) and 22.5% of cones (n = 225 cells). This suggests that rod and cone signals in the ON pathway are integrated in some RBCs before reaching AII amacrine cells. 相似文献
73.
McEwan L Taylor J Casswell M Entwistle R Jacoby K Gorry J Jacoby A Baker GA 《Epilepsy & behavior : E&B》2007,11(1):13-19
OBJECTIVE: The aim of this study was to investigate the knowledge and attitudes possessed by carers of people with epilepsy. METHODS: A postal survey of 2000 carers recruited from the membership list of a UK epilepsy charity was conducted using a standard set of questions. The questions covered their knowledge of epilepsy (e.g., estimating prevalence and identifying causes of epilepsy) and their attitudes (e.g., about the characteristics of people with epilepsy). RESULTS: Overall, 651 carers responded. Only 29% of carers were male, with the majority between 40 and 60 years of age. The majority of respondents (76%) overestimated the prevalence of epilepsy. Twenty-five percent believed that epilepsy was caused by stress. The majority of respondents believed that people with epilepsy were treated differently by others. Only a small percentage believed that people with epilepsy should be barred from such professions as teaching and nursing. CONCLUSIONS: Carers of people with epilepsy generally possessed high levels of knowledge about most aspects of epilepsy, and their attitudes toward those with epilepsy were benign. There were, however, particular groups who were more likely to hold more positive attitudes, and these included younger and better-educated individuals. Limitations of this study include that the sample was self-selected and that only a third of the people to whom the questionnaire was mailed responded. 相似文献
74.
75.
Jacoby A 《Current neurology and neuroscience reports》2008,8(4):339-344
This article discusses the concept of illness-related stigma and its relevance to consideration of the psychosocial impact
of epilepsy. It provides an overview of the recent literature on epilepsy-related stigma as it relates to the stigma experience
of people with epilepsy themselves and to the beliefs and attitudes held by other key target groups. The limitations of these
and previous studies are considered, and some advances in knowledge arising from them are highlighted. Finally, some suggestions
are made about possible areas for further investigation. 相似文献
76.
77.
Nonsurgical repositioning of central venous catheters 总被引:2,自引:0,他引:2
Long-term central venous catheters are placed for total parenteral nutrition and/or chemotherapy. These catheters are placed surgically and fixed to the subcutaneous tissues. Complications include infection, venous thrombosis, and mechanical problems. The authors developed a method to percutaneously reposition displaced central venous catheters. The procedure is performed with fluoroscopy and modified angiographic techniques. Fifteen patients underwent a total of 17 procedures. The initial success rate was 76%; the final success rate was 88%. Many central venous catheters can be salvaged with this low-morbidity procedure, which negates the need for surgical intervention. 相似文献
78.
目的运用饲喂低钙饲料的方法建立大鼠骨质疏松模型,结合骨密度、骨矿含量及uc OC/c OC等指标,探讨含VK2(MK-7)的益生菌粉、VD2及Ga的复配产品对防治骨质疏松的作用。方法 220 g~250 g雌性SD大鼠分为正常饲喂对照组、低钙饲料饲喂组、低剂量复配产品治疗组、高剂量复配产品治疗组,每组8只大鼠,试验进行前及试验结束后对每组大鼠进行DEXA测定,并对试验结束后每组大鼠的uc OC/c OC等血液指标进行测定。结果相对于正常对照组,低钙饲料饲喂组大鼠骨密度及骨矿含量值显著降低(P0.05)。灌胃复配产品高低剂量组大鼠骨密度及骨矿含量与低钙饲喂组相比显著提高(P005),且uc OC/c OC值显著降低(P0.05)。结论 VK2(MK-7)的益生菌粉、VD2的益生菌粉及Ga的复配产品具有防治骨质疏松的作用。 相似文献
79.
A Papadopoulou MO Rawashdeh GA Brown AS McNeish IW Booth 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(1):79-83
The short- and long-term effects of an elemental diet in children with acute Crohn's disease were compared with those of prednisolone in historical controls. Clinical remission was induced in 25 of 30 and in 18 of 28 episodes treated for six weeks with an elemental diet and prednisolone. Patients with proximal disease had longer remission after treatment with an elemental diet (p < 0.05) than did patients with colonic disease after treatment with prednisolone (p < 0.01). Disease activity index score improved in both groups compared with the pretreatment scores (p < 0.05). However, the improvement in the elemental diet group was significantly better than in the prednisolone group (p < 0.001). Changes in linear growth were better after treatment with an elemental diet compared with steroids (p < 0.001). Serum albumin and haematocrit concentrations all improved significantly in the children treated with an elemental diet (p < 0.001) but not in those treated with steroids. Thus an elemental diet was better than prednisolone in proximal disease and confirmed improved growth and nutritional status. 相似文献
80.
IJ Griffin TJ Cole KA Duncan AS Hollman MDC Donaldson 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(5):544-549
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty. 相似文献