全文获取类型
收费全文 | 162711篇 |
免费 | 14723篇 |
国内免费 | 9024篇 |
专业分类
耳鼻咽喉 | 1584篇 |
儿科学 | 2299篇 |
妇产科学 | 1397篇 |
基础医学 | 15961篇 |
口腔科学 | 2722篇 |
临床医学 | 20175篇 |
内科学 | 20289篇 |
皮肤病学 | 2139篇 |
神经病学 | 7249篇 |
特种医学 | 6244篇 |
外国民族医学 | 50篇 |
外科学 | 15589篇 |
综合类 | 33683篇 |
现状与发展 | 38篇 |
一般理论 | 10篇 |
预防医学 | 14617篇 |
眼科学 | 3540篇 |
药学 | 17403篇 |
164篇 | |
中国医学 | 10069篇 |
肿瘤学 | 11236篇 |
出版年
2025年 | 108篇 |
2024年 | 1945篇 |
2023年 | 2370篇 |
2022年 | 4998篇 |
2021年 | 6464篇 |
2020年 | 5111篇 |
2019年 | 4074篇 |
2018年 | 4183篇 |
2017年 | 4394篇 |
2016年 | 4294篇 |
2015年 | 6789篇 |
2014年 | 8691篇 |
2013年 | 9227篇 |
2012年 | 13422篇 |
2011年 | 14409篇 |
2010年 | 11069篇 |
2009年 | 9517篇 |
2008年 | 10900篇 |
2007年 | 10748篇 |
2006年 | 9797篇 |
2005年 | 8701篇 |
2004年 | 6485篇 |
2003年 | 6328篇 |
2002年 | 4945篇 |
2001年 | 3949篇 |
2000年 | 3151篇 |
1999年 | 2192篇 |
1998年 | 1239篇 |
1997年 | 1269篇 |
1996年 | 860篇 |
1995年 | 789篇 |
1994年 | 611篇 |
1993年 | 442篇 |
1992年 | 486篇 |
1991年 | 425篇 |
1990年 | 363篇 |
1989年 | 274篇 |
1988年 | 259篇 |
1987年 | 234篇 |
1986年 | 175篇 |
1985年 | 163篇 |
1984年 | 103篇 |
1983年 | 65篇 |
1982年 | 52篇 |
1981年 | 42篇 |
1980年 | 26篇 |
1979年 | 52篇 |
1978年 | 43篇 |
1976年 | 24篇 |
1973年 | 29篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Background:Defecation of patients with rectal carcinoma after operation cannot be controlled freely,which brings patients many mental burdens.Cocolyster operation can improve obviously the symptom. 相似文献
12.
13.
Expression of antibody heavy- and light-chain genes by transfection permits the production of monoclonal antibodies with improved biological and antigen-binding properties. The immunoglobulin genes are placed in vectors containing a gene for encoding a protein that provides a biochemically selectable function in eukaryotic cells; these vectors are transfected into myeloma and hybridoma cells. Selection of drug-resistant cells permits the efficient isolation of the rare cells that express the transfected DNA. By placing heavy and light chains on plasmids with different selectable markers, one can deliver heavy- and light-chain genes simultaneously to the same cell. The transfected immunoglobulin genes are efficiently expressed and the proteins produced are a faithful mirror of the genes that were introduced. Using the standard techniques of genetic engineering and gene transfection, we can now produce antibodies of widely varying structures, including chimeric antibodies with segments derived from different species. These antibodies provide useful reagents to study structure-function relationships within the antibody molecule. Ultimately it will be possible to produce a new generation of antibody molecules with improved antigen-binding properties and effector functions. 相似文献
14.
BACKGROUND: Dietary salt and fluid restriction is important in controlling fluid balance in patients on continuous ambulatory peritoneal dialysis (CAPD). However, it is often difficult to monitor patients' dietary total sodium intake (TSI). Usually, total sodium removal (TSR), the sum of urinary sodium removal (USR) and dialysate sodium removal (DSR), is suggested to represent TSI. In the present study, we investigated the reliability of using TSR as a surrogate to TSI in CAPD patients. METHODS: 40 clinically stable CAPD patients were closely followed for 3 months. Their TSI, USR, DSR, and fluid status were measured twice: at baseline and at the end of this study respectively. Fluid status was evaluated by bioimpedance analysis. Patients with increased sodium intake (group ISI) or decreased sodium intake (group DSI) (both >0.5 g/day or >21.74 mmol/day elemental sodium) were included in this study. RESULTS: There were 15 patients in group ISI and 9 patients in group DSI. During the follow-up, although TSI increased in group ISI and decreased in group DSI (p < 0.05), there were no significant changes in USR, DSR, or TSR in either group. No relationship was found between TSI and TSR. Changes in weight, blood pressure, urine volume, ultra-filtration, and small solute removal (Kt/V and creatinine clearance) were not statistically significant between the two groups. Fluid status deteriorated in group ISI and improved in group DSI (p < 0.05). CONCLUSIONS: Our study suggests that changes in total sodium intake do not lead to proportionate changes in total sodium removal in CAPD patients. Therefore, TSR (the sum of USR and DSR) should be used cautiously to monitor TSI in this patient population. 相似文献
15.
16.
17.
Twenty-seven in-patients with obstetric DIC in our hospital from Jan. 1971 to Dec. 1990 were analysed retrospectively. The incidence was 0.12% in the first decade and 0.02%, in the second, showing a difference of significance between them. The most common predisposing factors included amniotic fluid embolism, abruptio placenta and hemorrhagic shock. Bleeding from multi-organs in various extent and coagulation disorders occurred in all those 27 cases. [Besides anti-shock treatment, heparin was employed together with fibrinogen in 4 postpartum and 1 antepartum DIC patients, fibrinogen alone in 8 cases, and hysterectomy in 11 cases. 17 patients were saved and 9 died. It is important that early diagnosis and much attention paid to clinical characteristics together with serial laboratory tests. Key management should include prompt treatment and eradication of predisposing factors. Quick decision spite of to terminate the pregnancy and even hysterectomy should be done in some risks. 相似文献
18.
J. Lin W. Shiu W. T. Leung M. Tao N. Leung W. Y. Lau A. K. C. Li 《Cancer chemotherapy and pharmacology》1993,31(4):338-339
Summary A phase II study of high-dose ifosfamide in hepatocellular carcinoma was conducted among 17 Chinese patients. The dose of ifosfamide used was 2.5 g/m2 daily given as a continuous infusion for 5 days. In all, 15 patients were evaluable for tumour response. There was no complete or partial responder. The treatment was well tolerated. The most frequent toxicity was alopecia, which occurred in 11 patients, and 5 patients developed mild haematological toxicity. There was no evidence of liver or bladder toxicity. Overall, 14 patients were evaluable for survival. The median survival was 92 days (range, 30–568 days). We conclude that high-dose ifosfamide is well tolerated but ineffective in hepatocellular carcinoma in Chinese patients. 相似文献
19.
Membrane lipid composition and fluidity of a series of B16 melanoma cell variants with increased resistance to heat were analysed for changes within the lipid component that may contribute to the acquisition of heat resistance. Within one series of heat-resistant lines the cholesterol content of the cells decreased as their heat resistance increased. The most heat-resistant line, WH75, had 40 per cent less cholesterol than the parent line. No change in the composition of phospholipid fatty acids was found. An increased level of membrane fluidity in WH75 was demonstrated by electron paramagnetic resonance using 5- or 12-doxyl stearic acid. When challenged by heat the increase in membrane fluidity was similar for WH75 and for the parent line. Thus the increased heat resistance of the variants is probably not due to their ability to adapt to heat challenge by increasing membrane thermostability. The inverse relationship between heat resistance and cholesterol content was not demonstrated in two other series of heat-resistant variants. The cholesterol decrease, therefore, is not a universal response of cells as they acquire heat resistance. 相似文献
20.
周围性面神经麻痹称之面瘫,以口眼向一侧歪斜为主症,俗称口眼歪斜。本病如果治疗不及时或治疗不当,则久治不愈,给病人造成极大痛苦。若单用针刺治疗疗程较长,疗效不显著。我科在运用针灸按摩治疗本病的同时,对病人实施了针对性的全面的护理措施。现介绍如下。 相似文献