全文获取类型
收费全文 | 8356篇 |
免费 | 545篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 107篇 |
儿科学 | 482篇 |
妇产科学 | 136篇 |
基础医学 | 1148篇 |
口腔科学 | 272篇 |
临床医学 | 550篇 |
内科学 | 1970篇 |
皮肤病学 | 195篇 |
神经病学 | 742篇 |
特种医学 | 521篇 |
外科学 | 1031篇 |
综合类 | 44篇 |
一般理论 | 1篇 |
预防医学 | 670篇 |
眼科学 | 104篇 |
药学 | 460篇 |
1篇 | |
中国医学 | 21篇 |
肿瘤学 | 486篇 |
出版年
2023年 | 36篇 |
2022年 | 72篇 |
2021年 | 177篇 |
2020年 | 94篇 |
2019年 | 209篇 |
2018年 | 238篇 |
2017年 | 155篇 |
2016年 | 134篇 |
2015年 | 180篇 |
2014年 | 218篇 |
2013年 | 281篇 |
2012年 | 394篇 |
2011年 | 424篇 |
2010年 | 276篇 |
2009年 | 327篇 |
2008年 | 391篇 |
2007年 | 419篇 |
2006年 | 427篇 |
2005年 | 428篇 |
2004年 | 395篇 |
2003年 | 412篇 |
2002年 | 338篇 |
2001年 | 283篇 |
2000年 | 301篇 |
1999年 | 271篇 |
1998年 | 168篇 |
1997年 | 170篇 |
1996年 | 170篇 |
1995年 | 111篇 |
1994年 | 106篇 |
1993年 | 130篇 |
1992年 | 137篇 |
1991年 | 102篇 |
1990年 | 99篇 |
1989年 | 107篇 |
1988年 | 85篇 |
1987年 | 70篇 |
1986年 | 73篇 |
1985年 | 72篇 |
1984年 | 52篇 |
1983年 | 37篇 |
1982年 | 35篇 |
1981年 | 43篇 |
1980年 | 29篇 |
1979年 | 31篇 |
1978年 | 28篇 |
1977年 | 31篇 |
1976年 | 41篇 |
1975年 | 27篇 |
1973年 | 19篇 |
排序方式: 共有8941条查询结果,搜索用时 15 毫秒
51.
Machuca Santa Cruz J Julve Villalta E Galacho Bech A Pérez Rodríguez D Quiñonero Díaz A Alonso Dorrego JM Marín Martín JA 《Actas urologicas espa?olas》1999,23(1):43-50
We report 15 cases of spontaneous retroperitoneal haematoma. The etiology and the diagnostic and therapeutic procedures were evaluated. The haematoma source was the adrenal gland in 4 patients and the causes were pheochromocytoma (1), adenoma (1), myelolipoma (1) and idiopathic (1). In 10 patients the source was the kidney and the causes were angiomyolipoma rupture (6), renal cell carcinoma (3) and ureteral calculi (1). In the remaining case, the haematoma was produced by fibrinolytic and anticoagulant therapy in a patient with acute myocardial infarction. The imaging diagnostic techniques employed were abdominal ultrasonography and CT scan, which allowed the diagnosis of haematoma and showed his size and extension in all the cases. With these two techniques, and with the retrograde pyelography in one patient, we obtained the etiologic diagnosis in 12 of the 15 cases. Surgical treatment was performed in 12 patients (adrenalectomy in 2, simple nephrectomy in 3, radical nephrectomy in 5 and partial nephrectomy in 2). 相似文献
52.
53.
54.
Taoube KA Alonso Calderón JL Yandza T St Vil D Blanchard H 《Cirugía pediátrica : organo oficial de la Sociedad Espa?ola de Cirugía Pediátrica》1999,12(1):38-40
The congenital absence of the portal vein is a rare malformation, which has been generally discovered in association with another anomalies like a cardiac, gastrointestinal or genitourinary defects. With portal hypertension and hepatic cirrhosis, this anomaly is similar to spontaneous porto-systemic derivation, and for that not collateral venous drainage is present. In these patients, total interruption of mesentaric venous drainage during procurement of liver transplant produce a very important bowel and mesenteric edema, which can promote an injert fatal evolution. The authors present the first paediatric liver transplant, in a patient with portal venous agenesia, with de piggy-back technique was done and this complication was obviated, and a review of the literature about this issue is done. 相似文献
55.
56.
57.
A new microparticulate delivery system composed of a stabilizing gelatin/poloxamer microcore surrounded by a PLGA coat was designed to improve the stability of tetanus toxoid (TT) encapsulated in PLGA microspheres. Microcores were prepared by a spray-congealing technique and encapsulated within PLGA using an oil-in-oil (o/o) solvent evaporation technique. SEM analysis of the cross-sections of the microcapsules revealed the adequate encapsulation of the cores, showing an intimate contact between the core and the coating. This structure was responsible for an osmotic phenomenon observed in vitro, which led to the release of the encapsulated TT in a short period of time. Nevertheless, it was observed that the release was affected by the presence of the poloxamer in the core: microspheres without poloxamer in the core exhibit a faster release (2 h) than those that incorporate the surfactant (24 h). The in vivo evaluation of this system showed that the encapsulated toxoid induced a low but continuous levels of neutralizing antibodies (Nt), whereas those obtained for the control (aluminum phosphate-adsorbed toxoid) decreased after reaching the maximum level at 14 weeks. Moreover, the administration of a mixture of encapsulated and adsorbed TT led to significant higher and more prolonged Nt levels than those measured for the adsorbed toxoid. 相似文献
58.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
59.
Pérez JM López-Solera I Montero EI Brana MF Alonso C Robinson SP Navarro-Ranninger C 《Journal of medicinal chemistry》1999,42(26):5482-5486
The reaction of platinum salts with bis(naphthalimide), compound 1, yielded two Pt-bis(naphthalimide) complexes, compounds 2 and 3 which differ from each other in their leaving groups being 1,1-cyclobutane dicarboxylate or chloride, respectively. The testing of the cytotoxic activity of compounds 2 and 3 against several tumor cell lines indicated that both compounds may be endowed with important antineoplastic properties since they circumvent cisplatin resistance. At similar rates of DNA platination (r(b) = 0.025), compounds 2 and 3 unwind supercoiled pUC8 DNA by (48 +/- 2) degrees. Altogether, these data suggest (i) that the cytotoxic activity of compounds 2 and 3 may be due to a combined effect of platination and intercalation and (ii) that the bis(naphthalimide) ligand is a suitable "carrier" that favors DNA targeting by cis-Pt(II) centers. 相似文献
60.
Rodríguez Cruz MS González Alonso I Sánchez-Navarro A Sayalero Marinero ML 《Pharmaceutica acta Helvetiae》1999,73(5):237-245
The aim of the present study was to evaluate the influence of aluminium and iron on the in vitro dissolution kinetics of ciprofloxacin and ofloxacin as well as the usefulness of this type of in vitro data to predict modifications in in vivo absorption processes as a consequence of different factors, such as the widely documented in vivo interaction between quinolones and cations. Fitting of experimental data to different theoretical in vitro dissolution profiles was performed by non-linear regression methods and the statistical moments were calculated from raw experimental data. Analysis of residuals applied to dissolution curves as well as statistical comparison of the estimated parameters were carried out to evaluate the in vitro interaction. The results reveal significative modifications of the dissolution profiles of these quinolones as a consequence of the presence of cations, especially for Fe2+ which decreases 34.7% the maximum amount dissolved for ciprofloxacin and 29.1% for ofloxacin. Al3+ also produces a decrease of the total amount of quinolone dissolved although less relevant than Fe2+. Analysis of residuals proved to be the best statistical method to evaluate differences between whole dissolution profiles, at least under the experimental conditions used. 相似文献