全文获取类型
收费全文 | 16440篇 |
免费 | 1196篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 142篇 |
儿科学 | 438篇 |
妇产科学 | 446篇 |
基础医学 | 2083篇 |
口腔科学 | 675篇 |
临床医学 | 1698篇 |
内科学 | 3159篇 |
皮肤病学 | 227篇 |
神经病学 | 1631篇 |
特种医学 | 636篇 |
外国民族医学 | 1篇 |
外科学 | 2028篇 |
综合类 | 72篇 |
一般理论 | 33篇 |
预防医学 | 1714篇 |
眼科学 | 140篇 |
药学 | 1178篇 |
中国医学 | 14篇 |
肿瘤学 | 1338篇 |
出版年
2023年 | 122篇 |
2022年 | 80篇 |
2021年 | 212篇 |
2020年 | 227篇 |
2019年 | 306篇 |
2018年 | 484篇 |
2017年 | 439篇 |
2016年 | 436篇 |
2015年 | 375篇 |
2014年 | 428篇 |
2013年 | 821篇 |
2012年 | 1031篇 |
2011年 | 1107篇 |
2010年 | 560篇 |
2009年 | 429篇 |
2008年 | 1093篇 |
2007年 | 1144篇 |
2006年 | 1004篇 |
2005年 | 921篇 |
2004年 | 858篇 |
2003年 | 876篇 |
2002年 | 815篇 |
2001年 | 488篇 |
2000年 | 561篇 |
1999年 | 376篇 |
1998年 | 129篇 |
1997年 | 103篇 |
1996年 | 92篇 |
1995年 | 100篇 |
1994年 | 108篇 |
1993年 | 70篇 |
1992年 | 168篇 |
1991年 | 140篇 |
1990年 | 136篇 |
1989年 | 130篇 |
1988年 | 117篇 |
1987年 | 99篇 |
1986年 | 87篇 |
1985年 | 110篇 |
1984年 | 126篇 |
1983年 | 71篇 |
1982年 | 94篇 |
1981年 | 67篇 |
1980年 | 58篇 |
1979年 | 50篇 |
1978年 | 41篇 |
1977年 | 36篇 |
1974年 | 28篇 |
1973年 | 36篇 |
1971年 | 28篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Posterior dislocations of the sternoclavicular joint are uncommon, but are potentially quite serious. Radiologic diagnosis and management are frequently difficult. The specialized projections available are not widely known, and the role of plain films is poorly understood. The incidence, pathomechanics, and clinical manifestations of such dislocations are presented and the radiologic diagnosis is discussed. 相似文献
22.
R. de Wit G. Stoter D. T. Sleijfer S. B. Kaye P. H. de Mulder W. W. ten Bokkel Huinink P. J. Spaander M. de Pauw R. Sylvester 《British journal of cancer》1995,71(6):1311-1314
We have investigated whether an alternating induction chemotherapy regimen of PVB/BEP is superior to BEP in patients with poor-prognosis testicular non-seminoma. A total of 234 eligible patients were randomised to receive an alternating schedule of PVB/BEP for a total of four cycles or four cycles of BEP. Poor prognosis was defined as any of the following: lymph node metastases larger than 5 cm, lung metastases more than four in number or larger than 2 cm, haematogenic spread outside the lungs, such as in liver and bone, human chorionic gonadotrophin > 10,000 IU l-1 or alphafetoprotein > 1000 IU l-1. The complete response (CR) rates to PVB/BEP and BEP were similar, 76% and 72% respectively (P = 0.58). In addition, there was no significant difference in relapse rate, disease-free and overall survival at an average follow-up of 6 years. The 5-year progression-free and survival rates in both treatment groups were approximately 80%. The PVB/BEP regime was more toxic with regard to bone marrow function; the frequencies of leucocytes below 1000 microliters-1, leucocytopenic fever and platelets below 25,000 microliters-1, throughout four cycles were 28% vs 5% (P < 0.001), 16% vs 5% (P = 0.006), and 10% vs 1% (P = 0.001) respectively. Neuropathy also occurred more often in the PVB/BEP arm: 47% vs 25% (P = 0.001). This study shows that an alternating regimen of PVB/BEP is not superior to BEP and that it is more myelo- and neurotoxic. 相似文献
23.
Gunnar Franzn Olav G. Klausen Ronald T. Grenko John Carstensen Bo Nordenskjld 《The Laryngoscope》1991,101(6):669-673
A retrospective study was performed on 20 patients with adenoid cystic carcinomas of major salivary glands to see if DNA. patterns correlated with their prognoses. Fourteen tumors were found to be DNA. diploid; 6 were DNA aneuploid. Histologically, all DNA-aneu-ploid tumors had solid components, compared with only 5 of the DNA-diploid tumors. All of the DNA-aneuploid tumors recurred, in contrast to only 2 of the DNA-diploid tumors; the difference was highly significant (P<0.001). All of the patients with no recurrences had DNA-diploid tumors. In our study, DNA measurements of adenoid cystic carcinomas gave statistically significant information about prognosis and correlated to histological grading. We propose that evaluation of DNA content may be performed before planning the treatment of adenoid cystic carcinomas. 相似文献
24.
J H Beijnen L T Vlasveld J Wanders W W ten Bokkel Huinink S Rodenhuis 《The Annals of pharmacotherapy》1992,26(4):488-490
OBJECTIVE: A case in which a possible cisplatin interference with lithium pharmacokinetics is evaluated. DATA SYNTHESIS: A 36-year-old woman with disseminated cervical cancer and multiple metastatic lesions in both kidneys was being treated with five courses of bleomycin, vindesine, mitomycin C, and cisplatin. The patient had also been taking lithium carbonate for the management of a manic-depressive disorder. Serum and urinary lithium concentrations were measured daily during the first course of chemotherapy and on a periodic basis during and between the consecutive courses. Lithium concentrations remained within the therapeutic range during the first course and increased later in association with deterioration of the patient's renal function secondary to progressive disease in both kidneys. This required dose adjustments of lithium. CONCLUSIONS: Lithium therapy should be guided by serial serum concentrations in such patients. 相似文献
25.
Pia Hovbrandt Agneta Ståhl Susanne Iwarsson Vibeke Horstmann Gunilla Carlsson 《European journal of ageing》2007,4(4):201-211
Due to decreased functional capacity as well as high environmental demands there is a risk of diminishing activity outside
home in very old age (age 80+). In order to explore differences according to functional limitations (FL) among very old people
with respect to frequency of activity, perceived health, overall perception of neighbourhood environment, and perceived problems
in the pedestrian environment, data derived from a postal questionnaire survey to very old people living in an urban area
in Sweden were used. This explorative study is based on the sub-sample of people aged 80+ who reported outdoor activities
(n = 97). Four groups of respondents with different types of FL were identified: with no FL (n = 23), with only movement-related FL (n = 26), with only perception/cognition-related FL (n = 16), and with both movement- and perception/ cognition-related FL (n = 32). The majority of the respondents reported rather high frequency of activity outside home. When examining differences
between the four groups, the analysis indicated how the complexity of FL and perceived problems in the pedestrian environment
impacted on their activity performance. Persons with both movement- and perception/cognition-related FL were less satisfied
with their frequency of activity, experienced their health more negatively and experienced more problems in the pedestrian
environment than in the other groups. The findings from this study indicate the importance of considering combinations of
FL in creating supportive environments for activity and health. 相似文献
26.
Per Hartvig S.Å. Eckernäs Leif Lindström Bengt Ekblom Ulf Bondesson Hans Lundqvist Christer Halldin Kjell Någren Bengt Långström 《Psychopharmacology》1986,89(2):248-252
By means of positron emission tomography the uptake and kinetics of N-(methyl-11C)clozapine in different brain regions have been studied in Rhesus monkeys. 11C-clozapine rapidly entered the brain and maximum radioactive uptake was seen 5–12 min after administration. Highest uptake was measured in the striatum. Other regions with an uptake higher than in the cerebellum were thalamus and mesencephalon. The radioactivity from different brain regions decreased with an elimination half-life of about 5 h and parallelled the plasma kinetics of unlabelled clozapine. The striatum/cerebellum ratio of 11C-clozapine-derived radioactivity remained constant during the period studied and did not change after pretreatment with atropine. In contrast, the striatum/cerebellum ratio was somewhat lower after pretreatment with N-methylspiperone (NMSP), indicating competition for the same binding sites in the striatum. After pretreatment with increasing doses of clozapine, a dose-dependent protection of binding sites in the striatum for 11C-NMSP was seen. It is concluded that clozapine is more loosely bound to dopamine receptors in the striatum than N-methylspiperone and that the kinetics of clozapine in the brain parallel that in the plasma. The binding properties of clozapine within the brain may explain some of the clinical properties of the drug. 相似文献
27.
Deep vein thrombosis and fibrinolysis. Defective urokinase type plasminogen activator release. 总被引:1,自引:0,他引:1
M Levi A W Lensing H R Büller P Prandoni G Dooijewaard S Cuppini J W ten Cate 《Thrombosis and haemostasis》1991,66(4):426-429
In the present study 57 consecutive patients with a first episode of venographically proven deep vein thrombosis were investigated to evaluate the release of tissue-type plasminogen activator (t-PA) and of urokinase-type plasminogen activator (u-PA) in response to DDAVP stimulation as well as the resting plasminogen activator inhibitor (PAI) concentration, comparing this to the results obtained in 66 similar patients with a clinical suspicion of thrombosis but with a normal venogram. All assays were performed without knowledge of the patient's status. Four patients in the deep vein thrombosis-group (7%) had an absent u-PA antigen response upon DDAVP infusion, while a normal response was observed in all control subjects. Patients and controls showed similar increases in t-PA antigen level upon DDAVP. High resting PAI antigen levels were encountered in 5 patients in the deep vein thrombosis-group (9%) and in 6 subjects in the control group (9%). The results from this controlled study indicate that a defective release of u-PA may occur in patients with deep vein thrombosis and may have pathogenetic significance. Furthermore it is concluded that elevation of PAI levels cannot be considered as a specific risk factor for venous thrombosis. 相似文献
28.
A case of nonseminomatous testicular cancer and enlarged mediastinal lymph nodes, which were interpreted as metastases, is reported. When there was no change after two courses of chemotherapy, a mediastinoscopy was performed and the results showed sarcoidosis. 相似文献
29.
Deep vein thrombosis: new non-invasive diagnostic tests 总被引:2,自引:0,他引:2
30.
R A Valdés Olmos W W ten Bokkel Huinink J C Greve C A Hoefnagel 《Clinical nuclear medicine》1992,17(3):163-167
In six patients with doxorubicin-related cardiotoxicity, the severity of decrease in left ventricle ejection fraction (LVEF) was associated with faster myocardial I-123 MIBG washout rates. In four patients with severely decreased LVEF (range 19% to 28%), the 4-hour washout rate varied from 43% to 56%. In two patients with moderate cardiotoxicity (LVEF 42% and 43%), the washout rates were 37% and 35%, respectively. In contrast, in another patient thought to have initial left ventricular dysfunction (LVEF dropped from 66% to 54%), the myocardial I-123 MIBG retention rate was not reduced (6% washout). Subsequent continuation of chemotherapy in this patient was without complication. Reduced I-123 MIBG uptake in the left ventricle generally correlated with areas with abnormal Fourier amplitude values, but in one of the patients with moderate cardiotoxicity, the I-123 MIBG uptake was not reduced in a region with loss of amplitude, indicating dysfunction but probably no myocardial denervation. Analysis of the regional myocardial retention in patients with cardiotoxicity showed no significant difference in the I-123 MIBG washout rates of both segments with or without loss of amplitude. These data suggest that in spite of a localized loss of ventricular function demonstrated by radionuclide angiocardiography, doxorubicin-related cardiotoxicity appears to be based on a global process of myocardial adrenergic derangement. 相似文献