全文获取类型
收费全文 | 2375030篇 |
免费 | 194625篇 |
国内免费 | 4209篇 |
专业分类
耳鼻咽喉 | 34264篇 |
儿科学 | 72746篇 |
妇产科学 | 62929篇 |
基础医学 | 334865篇 |
口腔科学 | 67522篇 |
临床医学 | 215514篇 |
内科学 | 468569篇 |
皮肤病学 | 47930篇 |
神经病学 | 200771篇 |
特种医学 | 95956篇 |
外国民族医学 | 886篇 |
外科学 | 360384篇 |
综合类 | 56217篇 |
现状与发展 | 1篇 |
一般理论 | 977篇 |
预防医学 | 190606篇 |
眼科学 | 55462篇 |
药学 | 177526篇 |
4篇 | |
中国医学 | 4365篇 |
肿瘤学 | 126370篇 |
出版年
2018年 | 24204篇 |
2016年 | 20575篇 |
2015年 | 23278篇 |
2014年 | 33532篇 |
2013年 | 50828篇 |
2012年 | 68734篇 |
2011年 | 72272篇 |
2010年 | 42470篇 |
2009年 | 40860篇 |
2008年 | 68757篇 |
2007年 | 73097篇 |
2006年 | 73995篇 |
2005年 | 72039篇 |
2004年 | 69333篇 |
2003年 | 67012篇 |
2002年 | 66259篇 |
2001年 | 112450篇 |
2000年 | 116524篇 |
1999年 | 98333篇 |
1998年 | 27858篇 |
1997年 | 25522篇 |
1996年 | 25448篇 |
1995年 | 24609篇 |
1994年 | 23159篇 |
1993年 | 21552篇 |
1992年 | 79386篇 |
1991年 | 76393篇 |
1990年 | 73575篇 |
1989年 | 70841篇 |
1988年 | 65846篇 |
1987年 | 64800篇 |
1986年 | 61334篇 |
1985年 | 58399篇 |
1984年 | 44222篇 |
1983年 | 37657篇 |
1982年 | 22886篇 |
1981年 | 20332篇 |
1980年 | 19034篇 |
1979年 | 41299篇 |
1978年 | 28985篇 |
1977年 | 24346篇 |
1976年 | 22832篇 |
1975年 | 23964篇 |
1974年 | 29638篇 |
1973年 | 28042篇 |
1972年 | 26226篇 |
1971年 | 24151篇 |
1970年 | 22752篇 |
1969年 | 21087篇 |
1968年 | 19135篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.
902.
Dihydroxyacetone (DHA), a browning agent, protects photosensitive rats and humans against long ultraviolet radiation (UVA, 320-400 nm) and visible (blue) light. The photoprotective efficacy of DHA and structurally similar compounds was assessed as prevention of edema in the paws of psoralen-sensitized rats, after exposure to blacklight fluorescent lamps. Methylglyoxal produced a yellow-brown color and provided nearly the same protection as DHA, whereas monohydroxyacetone did not color the skin and afforded little or no protection. Glyceraldehyde provided a moderate amount of protection, which was enhanced by prior exposure of the agent to alkaline pH. A solution of 5-hydroxymethylfurfuraldehyde was yellow and provided minimal protection by staining the skin rather than browning it. We conclude that the ability to produce a brown color in skin is a useful criterion for screening compounds for photoprotective efficacy against UVA radiation. 相似文献
903.
VECURONIUM AND ATRACURIUM IN PATIENTS WITH END-STAGE RENAL FAILURE: A Comparative Study 总被引:2,自引:0,他引:2
LEPAGE J. Y.; MALINGE M.; COZIAN A.; PINAUD M.; BLANLOEIL Y.; SOURON R. 《British journal of anaesthesia》1987,59(8):1004-1010
Twenty patients with end-stage renal failure, undergoing kidneytransplantation, were assigned randomly to receive either vecuroniumor atracurium under evoked twitch tension control. The cumulative-dosetechnique was used to obtain 95% twitch depression (vecuronium:initial bolus 15 µg kg1, increments 6 µgkg1; atracurium: initial bolus 100 µg kg1,increments 40 µg kg1). Using ED95 values derivedfrom the log-probit dose-response curves, vecuronium was 4.6times more potent than atracurium. The durations of action ofthe initial cumulativedoses (from end of injection of the lastincrement to 25% recovery) were 11.1± 3.3 min for vecuroniumand 16.2±3.9 min for atracurium (P < 0.05). In termsof duration of action of the maintenance doses (vecuronium one-quarterof the total incremental dose; atracurium one-third) some cumulationwas observed with vecuronium (interaction time x treatment;cumulation ratio 1.46 ±0.31 v. 0.98±0.10 for atracurium,P< 0.001). After 2 h of surgery, the mean recovery times(25% to 75% twitch height) did not differ (18.5±2.8 minand 16.7±4.4 min). It is concluded that vecuronium mightbe less safe than atracurium in patients with end-stage renalfailure undergoing prolonged operations. 相似文献
904.
In a prospective study 90 patients who had confirmed abruption of the placenta were compared with a control group. Significantly more patients who had abruptio placentae were unmarried, smoked cigarettes, received no antenatal care, had coitus within the 48 hours preceding delivery, developed intrapartum hypertension and had a lower ponderal index than the controls. More patients with abruptio placentae had proteinuria and antepartum hypertension but statistical significance was not reached. In addition, the incidence of intra-uterine growth retardation was higher in these patients. 相似文献
905.
906.
907.
Phase I study of high-dose cytosine arabinoside and etoposide in patients with advanced malignancies
Bayard L. Powell Hyman B. Muss Robert L. Capizzi Mary E. Caponera Douglas R. White Patricia J. Zekan James N. Atkins Don V. Jackson Jr. Frederick Richards II John B. Craig Julia M. Cruz Charles L. Spurr 《Cancer chemotherapy and pharmacology》1987,19(3):250-252
Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m2 as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m2×2 doses of ara-C and 50 mg/m2 of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182 相似文献
908.
Platelet antibodies in systemic lupus erythematosus 总被引:2,自引:0,他引:2
C. Kaplan P. Champeix D. Blanchard J. Y. Muller J. P. Cartron 《British journal of haematology》1987,67(1):89-93
In systemic lupus erythematosus (SLE), the precise cause of the thrombocytopenia is unknown. Since platelet associated IgG is increased in many patients, it has been suggested that the destruction of platelets might be dependent on specific antibodies. In nine patients with SLE, platelet associated immunoglobulins were found together with free serum antibody which bound to platelets from all normal subjects. Using an immunoblotting technique with membrane proteins from normal platelets incubated with patient sera, target antigens were localized on a band of mol wt 108,000 in two cases (B. and N.) and on a band of mol wt 66,000 in a third (M.). When the same technique was applied to autologous platelets of patient N., autoantibody binding to the protein of mol wt 108,000 was demonstrated. The antigenic determinants were not removed from the platelets by enzyme treatment or by disulphide bond reduction, and were localized in the cytoplasmic fraction of the platelets. 相似文献
909.
910.
Alcoholic liver disease: an IgA-associated disorder 总被引:1,自引:0,他引:1