全文获取类型
收费全文 | 5135篇 |
免费 | 223篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 120篇 |
儿科学 | 145篇 |
妇产科学 | 229篇 |
基础医学 | 657篇 |
口腔科学 | 29篇 |
临床医学 | 340篇 |
内科学 | 1351篇 |
皮肤病学 | 186篇 |
神经病学 | 301篇 |
特种医学 | 127篇 |
外科学 | 655篇 |
综合类 | 42篇 |
一般理论 | 1篇 |
预防医学 | 263篇 |
眼科学 | 76篇 |
药学 | 442篇 |
中国医学 | 4篇 |
肿瘤学 | 409篇 |
出版年
2023年 | 18篇 |
2022年 | 89篇 |
2021年 | 212篇 |
2020年 | 60篇 |
2019年 | 100篇 |
2018年 | 120篇 |
2017年 | 95篇 |
2016年 | 108篇 |
2015年 | 130篇 |
2014年 | 168篇 |
2013年 | 229篇 |
2012年 | 381篇 |
2011年 | 430篇 |
2010年 | 196篇 |
2009年 | 116篇 |
2008年 | 310篇 |
2007年 | 376篇 |
2006年 | 347篇 |
2005年 | 328篇 |
2004年 | 337篇 |
2003年 | 352篇 |
2002年 | 255篇 |
2001年 | 42篇 |
2000年 | 36篇 |
1999年 | 31篇 |
1998年 | 30篇 |
1997年 | 35篇 |
1996年 | 23篇 |
1995年 | 23篇 |
1994年 | 13篇 |
1993年 | 24篇 |
1992年 | 25篇 |
1991年 | 16篇 |
1990年 | 20篇 |
1989年 | 23篇 |
1988年 | 23篇 |
1987年 | 27篇 |
1986年 | 15篇 |
1985年 | 18篇 |
1984年 | 15篇 |
1983年 | 17篇 |
1982年 | 10篇 |
1981年 | 16篇 |
1979年 | 15篇 |
1978年 | 10篇 |
1977年 | 15篇 |
1974年 | 9篇 |
1970年 | 8篇 |
1967年 | 8篇 |
1966年 | 11篇 |
排序方式: 共有5377条查询结果,搜索用时 140 毫秒
1.
T Hogenkamp T F Wienker F Majewski A Gal 《Klinische Monatsbl?tter für Augenheilkunde》1987,191(4):307-309
Retinitis pigmentosa (RP) is the most common hereditary dystrophic disease of the retina. About 10% of the affected families show the X-linked trait. The close link observed between the gene locus (RP2) and a polymorphic DNA marker (DXS7) on the proximal short arm of the X-chromosome permits an indirect genotype diagnosis and can be helpful in carrier detection and genetic counseling. A case is presented in which the carrier risk of a female consultant dropped from 50% a priori to less than 2% by the use of clinical findings and DNA analysis. 相似文献
2.
3.
Proprioception is a term covering together joint position sense, kinesthesia and integration of these stimuli in the central nervous system which is needed to keep homeosthasis of joints during motion. The aim of this study is to present authors originally created measuring device working according to the principles of Barrett, aiming at evaluation of proprioception of the knee. The construction of this device is based on the Summer chair, model UPR-01B, working in connection with Bosh goniometer DWM-40L measuring angles with a precision of 0,1 degree. The device presented in this study fulfills all criteria required for this kind of apparatus and may be an alternative to other constructs produced commercially and available on the market. 相似文献
4.
Antioxidative and anti-inflammatory effects of repaglinide in plasma of diabetic animals. 总被引:5,自引:0,他引:5
Anna Gumieniczek Hanna Hopka?a Jacek Roliński Agnieszka Bojarska-Junak 《Pharmacological research》2005,52(2):162-166
Oxidative stress, defined as an imbalance between the production of reactive oxygen species (ROS) and antioxidant defense, is considered to be an important pathogenic factor in diabetes mellitus and its complications. In diabetic state, ROS might also be implicated in promoting a state of systemic inflammation. Recently, it was demonstrated that antioxidant therapy could be used to stop the initiation and propagation of this inflammatory response. Repaglinide is a new oral antidiabetic agent with a possible antioxidant activity. Therefore, in the present study, a possible therapeutic value of repaglinide in ameliorating the oxidative and inflammatory processes was tested in diabetic animals. In the study, the levels of total antioxidant status (TAS), ascorbic acid (AA), protein carbonyl groups (PCG) and interleukin-6 (IL-6) were determined in plasma of diabetic rabbits after 4 and 8 weeks of repaglinide treatment (1mg daily). Ex vivo analysis revealed that there were significant differences in these markers between hyperglycemic and control animals (P<0.05). Some of these parameters were ameliorated by repaglinide treatment. In diabetic rabbits treated with repaglinide, protein oxidation was diminished by 17.8% after 8 weeks of experiment. The level of AA in plasma of diabetic treated animals was higher than in non-treated diabetic groups (by 9.4 and 22.6% after 4 and 8 weeks, respectively). In diabetic treated animals, the TAS level was also significantly increased (by 23.6 and 16.7%). However, in diabetic rabbits, repaglinide did not affect the concentration of IL-6. 相似文献
5.
6.
Anna Plachcinska Jacek Kusmierek Maciej Kosmider Malgorzata Bienkiewicz Julian Liniecki 《European journal of nuclear medicine and molecular imaging》1995,22(3):193-200
A quantified evaluation of planar cardiac perfusion scintigrams (the objective of the study), obtained using technetium-99m methoxyisobutylisonitrile (MIBI) was performed on the basis of an analysis of circumferential profile curves, representing the perfusion as seen in three typical projections. The analysis involved the curves obtained both at rest and after stress, and was based on a comparison of their shape (trend) with the normal trend (normative evaluation). The latter was obtained by means of an original method of iterative fitting of individual curves into the database. The base consisted of curves recorded in 53 patients (separately in males and females) with normal perfusion of the left ventricle (group I, the reference group). A group of 90 patients suspected of having coronary artery disease (group II) was subdivided into two subgroups on the basis of coronary arteriography: (a) those with and (b) those without critical stenosis of at least one artery. Profile curves characterising the LV perfusion were obtained at rest and after stress. Defects of perfusion were quantified by comparison of individual curves with the normal trends. By means of multivariate analysis it was demonstrated that vectors of mean values characterising the scintigraphically assessed defects of LV perfusion in the two subgroups of group II differed very significantly (P<10–5). Applying methods of discriminant analysis, a classification of patients from group II was performed into those with probable defects of perfusion and those free of such defects. The sensitivity, specificity and accuracy of diagnosis of coronary ischaemia, based on quantified planar99mTc-MIBI scintigraphy, reached 86%, 87% and 87%, respectively. 相似文献
7.
8.
Edward Malec Katarzyna Januszewska Jacek Kolcz Tomasz Mroczek 《European journal of cardio-thoracic surgery》2003,23(5):728-33; discussion 733-4
OBJECTIVE: The aim of this study was to assess changes in early and late haemodynamic status after the Norwood procedure (NP), caused by the implementation of right ventricle-to-pulmonary artery shunt (RV-PA). METHODS: A consecutive series of 68 children with hypoplastic left heart syndrome underwent NP: Group 1 (n=31) with the application of a modified Blalock-Taussig shunt and Group 2 (n=37) with RV-PA. Haemodynamic data from the early postoperative period (72 h after the operation) and cardiac catheterisation data, as well as blood tests before the hemi-Fontan procedure (HF) were analysed. Univariate (chi(2) test, Mann-Whitney's and Student's t-tests) and multiple regression analysis were carried out. RESULTS: In Group 1, circulatory collapse requiring resuscitation occurred in 15 (48.4%) children, within 72 h after the procedure. The resuscitation was unsuccessful in nine (29%) cases. The operative mortality (30 days) was 35%. In Group 2, two (5%) children died within the early and two (5%) within the late postoperative period. The postoperative course in the remaining children from Group 2 was uneventful. In Group 2 there was a significantly higher mean diastolic pressure after NP (P<0.05). The arterial pulse pressure after NP was significantly lower in Group 2 (P<0.05). Before HF, the application of RV-PA was associated with a lower Qp:Qs ratio (P=0.020), lower aortic pulse pressure (P=0.004) and lower aortic oxygen saturation (P=0.039). CONCLUSIONS: A stable haemodynamic status due to independent coronary perfusion, higher diastolic and lower pulse pressure is the most advantageous effect of RV-PA, resulting in a lower mortality and morbidity after NP. A lower Qp:Qs ratio eliminates the danger of the ventricular volume overload and ensures good conditions for the development of the pulmonary circulation before HF. 相似文献
9.
A case of tracheal agenesis, a rare foregut malformation, is described. This malformation is combined with a tracheo-oesophageal fistula, furthermore with rectal and anal atresia, cardiac malformations, dysplastic kidneys, wedge-shaped vertebrae, and cerebellar hypoplasia. Since a tracheo-oesophageal fistula is a possible component of the VACTERL Association [(V) vertebral defects, (A) anal atresia, (C) cardial malformations, (T) tracheo-(E)-oesophageal fistula, (R) renal or (L) limb malformations], similar cases are reviewed from the literature and their relationship to this association is discussed. 相似文献
10.
Effects of a new pteridine derivative on urinary sodium, potassium and magnesium excretion in conscious saline-loaded rats.
下载免费PDF全文
![点击此处可从《British journal of pharmacology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
T. Netzer F. Ullrich H. Priewer M. Majewski E. Mutschler 《British journal of pharmacology》1992,106(1):222-226
1. Two recently synthesized pteridine derivatives (RPH 3036; RPH 3038) were tested in conscious saline-loaded rats and showed natriuretic and antimagnesiuretic properties but hardly reduced potassium excretion. 2. In the same model a dose-response curve was performed for RPH 3036. ED50 and Emax values were calculated for the natriuretic (ED50 = 13.4 mumol kg-1; Emax = 1.08 mmol kg-1) and antimagnesiuretic (ED50 = 11.3 mumol kg-1; Emax = -0.099 mmol kg-1) properties of RPH 3036. There were no significant changes of potassium and calcium excretion. 3. After a single dose of RPH 3036 (100 mumol kg-1) the time course of electrolyte excretion was analysed over 6 h. RPH 3036 did not show any significant effects on renal potassium and calcium excretion whereas a pronounced decrease (P less than 0.01) in renal magnesium excretion was evident during the 6 h. A moderate increase of sodium excretion was observed only after 3, 5 and 6 h. 4. A selective reduction of magnesium secretion in the late distal tubule and collecting duct was proposed as a possible mechanism of action of RPH 3036. This would explain the fast onset of action as well as the lack of antikaliuretic and anticalciuretic effects. The high selectivity of RPH 3036 makes it potentially valuable for the future investigation of renal magnesium transport. 相似文献