全文获取类型
收费全文 | 1611篇 |
免费 | 91篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 151篇 |
妇产科学 | 17篇 |
基础医学 | 170篇 |
口腔科学 | 47篇 |
临床医学 | 155篇 |
内科学 | 362篇 |
皮肤病学 | 23篇 |
神经病学 | 32篇 |
特种医学 | 470篇 |
外科学 | 100篇 |
综合类 | 28篇 |
预防医学 | 43篇 |
眼科学 | 13篇 |
药学 | 51篇 |
中国医学 | 3篇 |
肿瘤学 | 58篇 |
出版年
2022年 | 4篇 |
2021年 | 7篇 |
2020年 | 9篇 |
2019年 | 7篇 |
2018年 | 16篇 |
2017年 | 10篇 |
2016年 | 22篇 |
2015年 | 27篇 |
2014年 | 26篇 |
2013年 | 56篇 |
2012年 | 21篇 |
2011年 | 20篇 |
2010年 | 72篇 |
2009年 | 56篇 |
2008年 | 31篇 |
2007年 | 23篇 |
2006年 | 27篇 |
2005年 | 18篇 |
2004年 | 14篇 |
2003年 | 13篇 |
2002年 | 19篇 |
2001年 | 13篇 |
2000年 | 21篇 |
1999年 | 25篇 |
1998年 | 133篇 |
1997年 | 118篇 |
1996年 | 124篇 |
1995年 | 91篇 |
1994年 | 74篇 |
1993年 | 81篇 |
1992年 | 22篇 |
1991年 | 21篇 |
1990年 | 15篇 |
1989年 | 59篇 |
1988年 | 44篇 |
1987年 | 49篇 |
1986年 | 45篇 |
1985年 | 47篇 |
1984年 | 24篇 |
1983年 | 31篇 |
1982年 | 34篇 |
1981年 | 20篇 |
1980年 | 36篇 |
1979年 | 14篇 |
1978年 | 15篇 |
1977年 | 17篇 |
1976年 | 23篇 |
1975年 | 24篇 |
1971年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有1724条查询结果,搜索用时 20 毫秒
71.
The heterogeneity of type IIA von Willebrand's disease: studies with protease inhibitors 总被引:6,自引:0,他引:6
Batlle J; Lopez Fernandez MF; Campos M; Justica B; Berges C; Navarro JL; Diaz Cremades JM; Kasper CK; Dent JA; Ruggeri ZM 《Blood》1986,68(6):1207-1212
The absence of large von Willebrand factor (vWF) multimers from plasma is a characteristic of Type IIA von Willebrand's disease (vWD) and is thought to contribute to the clinical expression of this disorder. Recently, three IIA patients have been reported in whom intermediate and large multimers could be restored if blood were collected in 5 mm EDTA, 6 mmol/L N-ethylmaleimide, and 1 mmol/L leupeptin. This suggested that absence of large multimers resulted from in vitro proteolysis. We have now collected blood from ten Type IIA vWD patients in these inhibitors but were not able to detect large multimers in the plasma of any of them. In addition, intermediate-sized multimers were reduced or completely absent in all. The inclusion of inhibitors in the citrate anticoagulant, as compared to citrate alone, was found to increase the relative proportion of intermediate multimers in some patients but had no effect in others, and in none did it restore large multimers to plasma. The results with platelet vWF were more varied. Four patients showed an absence or decrease of large multimers, whereas in seven patients large multimers were present. When compared with citrate anticoagulant alone, the inclusion of inhibitors in the anticoagulant had little or no effect on the platelet multimeric pattern. 1-Deamino-8- D-Arginine Vasopressin (DDAVP) was administered to six patients from five families. Two patients from one family showed complete correction and a third patient showed almost complete correction of her bleeding time. Two patients showed minimal correction and one showed no detectable correction. An increase in multimer size after DDAVP tended to be associated with correction of the bleeding time. However, in no case did the largest multimers appear in plasma even in patients with complete bleeding time correction. The presence or absence of inhibitors in the anticoagulant had little or no effect on the multimeric pattern after DDAVP. These results indicate that Type IIA vWD is a heterogeneous disorder in which absence of largest and intermediate multimers is an in vivo phenomenon. 相似文献
72.
Marrow transplantation with or without donor buffy coat cells for 65 transfused aplastic anemia patients 总被引:4,自引:3,他引:4
Storb R; Doney KC; Thomas ED; Appelbaum F; Buckner CD; Clift RA; Deeg HJ; Goodell BW; Hackman R; Hansen JA; Sanders J; Sullivan K; Weiden PL; Witherspoon RP 《Blood》1982,59(2):236-246
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%). 相似文献
73.
ABM Kharsany N Hancock JA Frohlich HR Humphries SS Abdool Karim Q Abdool Karim 《HIV medicine》2010,11(10):661-665
Objectives
The aim of this study was to evaluate the HIV‐1 RNA pooled nucleic acid amplification testing (NAAT) strategy to screen pregnant women in the ‘window period’ of acute HIV infection (AHI) in rural South Africa.Methods
In 2007 and 2008, 750 consecutive pregnant women on their first antenatal care visit to a primary health care clinic were tested anonymously for HIV infection. HIV‐1 RNA pooled NAAT was performed on HIV antibody‐negative samples. All positive pools were tested individually and positive samples were classified as incident cases to calculate HIV incidence.Results
The overall HIV prevalence was 37.3% [95% confidence interval (CI) 34.3–41.3]. Of the 467 HIV antibody‐negative samples, four (0.9%) were HIV‐1 RNA‐positive. The mean viral load in the four samples was 386 260 HIV‐1 RNA copies/mL (range 64 200–1 228 130). The HIV incidence was 11.2% per year (95% CI 0.3–22.1) and all women with AHI were ≤21 years of age.Conclusions
Identifying AHI in pregnancy is important for health interventions to reduce perinatal and heterosexual transmission of HIV, and to estimate HIV incidence for epidemiological surveillance. 相似文献74.
75.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
76.
77.
78.
Dios Castro E Maquet Dusart JA 《Archivos de la Sociedad Espa?ola de Oftalmología》2000,75(11):775-778
PURPOSE/METHOD: We present a case of a patient who developed recurrent epithelial herpes simplex keratitis after starting treatment with latanoprost. Her ophthalmic history was only remarkable for a past episode of herpetic keratitis 21 years previously. RESULTS/CONCLUSIONS: Episodes of herpetic keratitis were under remission only when latanoprost was discontinued. No recurrences of herpes simplex keratitis have been observed since then. Latanoprost usage might be associated with recurrent episodes of herpes simplex keratitis in patients with previous history of ocular herpes simplex virus infection. 相似文献
79.
Monge-Argiles J Maloteaux J Van Den Bergh P Sindic C 《Neurología (Barcelona, Spain)》2002,17(2):110-112
We report a patient with a peripheral neuropathy as the first symptom of sarcoidosis. The systemic illness was proved by the presence of typic granulomes in the bone marrow. The fact that sarcoidosis is the cause for the neuropathy is supported by the temporary relation and by the good response of all clinical picture to the corticosteroid therapy.Sarcoid neuropathy can rarely be the presenting feature of sarcoidosis. 相似文献
80.