全文获取类型
收费全文 | 97582篇 |
免费 | 3844篇 |
国内免费 | 228篇 |
专业分类
耳鼻咽喉 | 1443篇 |
儿科学 | 2980篇 |
妇产科学 | 2476篇 |
基础医学 | 13265篇 |
口腔科学 | 2582篇 |
临床医学 | 5905篇 |
内科学 | 22350篇 |
皮肤病学 | 2761篇 |
神经病学 | 7658篇 |
特种医学 | 2064篇 |
外国民族医学 | 2篇 |
外科学 | 12237篇 |
综合类 | 463篇 |
一般理论 | 25篇 |
预防医学 | 11116篇 |
眼科学 | 2226篇 |
药学 | 7393篇 |
中国医学 | 315篇 |
肿瘤学 | 4393篇 |
出版年
2023年 | 541篇 |
2022年 | 322篇 |
2021年 | 1592篇 |
2020年 | 805篇 |
2019年 | 1857篇 |
2018年 | 3255篇 |
2017年 | 1938篇 |
2016年 | 1855篇 |
2015年 | 2134篇 |
2014年 | 2281篇 |
2013年 | 3720篇 |
2012年 | 6311篇 |
2011年 | 6395篇 |
2010年 | 3270篇 |
2009年 | 2328篇 |
2008年 | 5304篇 |
2007年 | 5606篇 |
2006年 | 5456篇 |
2005年 | 5493篇 |
2004年 | 5063篇 |
2003年 | 4695篇 |
2002年 | 4459篇 |
2001年 | 3141篇 |
2000年 | 3336篇 |
1999年 | 2647篇 |
1998年 | 462篇 |
1996年 | 312篇 |
1992年 | 1256篇 |
1991年 | 1153篇 |
1990年 | 1083篇 |
1989年 | 968篇 |
1988年 | 881篇 |
1987年 | 889篇 |
1986年 | 823篇 |
1985年 | 789篇 |
1984年 | 583篇 |
1983年 | 458篇 |
1979年 | 591篇 |
1978年 | 345篇 |
1976年 | 318篇 |
1975年 | 346篇 |
1974年 | 528篇 |
1973年 | 489篇 |
1972年 | 428篇 |
1971年 | 392篇 |
1970年 | 464篇 |
1969年 | 425篇 |
1968年 | 405篇 |
1967年 | 370篇 |
1966年 | 314篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
R. G. Aguilera J. P. López R. R. Aldosa G. Rius-Espina 《International urology and nephrology》1990,22(4):367-371
A study of 16 patients who underwent intralbugineous testicular implants during the practice of orchiectomy is presented.
In 14 cases of prostatic carcinoma, after bilateral subcapsular orchiectomy intralbugineous prostheses were implanted and
in 2 other cases of testicular torsion unilateral prosthesis was implanted.
With this new, easily executed technique the size, mobility and testicular sensibility are maintained. 相似文献
92.
C Csonka G Gyurkó P Halász G Vekszler 《Magyar traumatológia, orthopaedia és helyreállító sebészet》1990,33(1):46-50
Authors report on arterial injuries in a 2-year material of hand injured. The combination of injuries observed and the methods of treatment are described. Attention is called to the fact, that because of anatomical characteristics of these regions, the diagnosis of arterial injuries is not always easy. Four cases of their own are briefly described in whom the arterial injury could be stated only at the development of complications (pulsating haematoma, false aneurysm, later bleeding). The importance of the primary careful treatment and the significance of the examination of the circulation (Allen's test, Doppler) are stressed. 相似文献
93.
94.
R. Gil-Grande J. M. Aguado C. Pastor M. García-Bravo C. Gómez-Pellico F. Soriano A. R. Noriega 《European journal of clinical microbiology & infectious diseases》1995,14(1):64-67
A patient with culture-negative endocarditis was diagnosed with Q fever endocarditis based on the results of serological tests and positive leukocyte cultures obtained using conventional viral cultures and the shell vial technique. This case report suggests that isolation ofCoxiella burnetii from blood may allow better diagnostic and therapeutical evaluation of patients with Q fever endocarditis. The use of both conventional and shell vial viral cultures is recommended for the isolation ofCoxiella burnetii from the blood of patients with apparently culture-negative endocarditis. 相似文献
95.
96.
S Ponce G Orive R M Hernández A R Gascón J M Canals M T Mu?oz J L Pedraz 《Journal of controlled release》2006,116(1):28-34
Alginates are the most employed biomaterials for cell encapsulation due to their abundance, easy gelling properties and apparent biocompatibility. However, as natural polymers different impurities including endotoxins, proteins and polyphenols can be found in their composition. Several purification protocols as well as different batteries of assays to prove the biocompatibility of the alginates in vitro have been recently developed. However, little is known about how the use of alginates with different purity grade may affect the host immune response after their implantation in vivo. The present paper investigates the long-term functionality and biocompatibility of murine erythropoietin (EPO) secreting C2C12 cells entrapped in microcapsules elaborated with alginates with different properties (purity, composition and viscosity). Results showed that independently of the alginate type employed, the animals presented elevated hematocrit levels until day 130, remaining at values between 70-87%. However, histological analysis of the explanted devices showed higher overgrowth around non-biomedical grade alginate microcapsules which could be directly related with higher impurity content of this type of alginate. Although EPO delivery may be limited by the formation of a fibrotic layer around non-biomedical grade alginate microcapsules, the high EPO secretion of the encapsulated cells together with the pharmacodynamic behaviour and the angiogenic and immune-modulatory properties of EPO result in no direct correlation between the biocompatibility of the alginate and the therapeutic response obtained. 相似文献
97.
Alicia Gómez-Barrio David Montero-Pereira Juan J. Nogal-Ruiz José A. Escario Susana Muelas-Serrano Vladimir V. Kouznetsov Leonor Y. Vargas Méndez Juan M. Urbina Gonzáles Carmen Ochoa 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(1):73-78
A study of some antiparasitic properties of several homoallylamines and related tetrahydroquinolines and quinolines, previously
described, was carried out using in vitro activity assays against the epimastigote form of Trypanosoma cruzi and against Trichomonas vaginalis. Unspecific cytotoxicity against murine macrophages was also studied. Although the antichagasic and trichomonacidal activities
are not comparable to those of the standard drugs, nifurtimox and metronidazole, some of the compounds exhibit an interesting
specific antiparasitic activity. 相似文献
98.
F. M. González Valverde F. Mauri Barberá M. Molto Aguado N. Torregrosa A. Hernández Quiles F. Menárguez Pina M. J. Gómez Ramos M. García Real J. A. Barreras Mateos J. L. Vázquez Rojas 《European Surgery》2004,36(4):253-256
Summary BACKGROUND: Endometriosis is a relatively common pathology in women of childbearing age and of low parity but rarely shows
extraperitoneal involvement. The main aim of this paper is to raise the attention of specialists to the necessity of carrying
out penetrating diagnosis of nonspecific extraperitoneal masses occurring in women of reproductive age. METHODS: We performed
a retrospective review of six patients diagnosed with extraperitoneal endometriosis who were treated at the Vega Baja University
Hospital (Spain) during the last 5 years. RESULTS: Surgical treatment had positive results in five patients. The preoperative
diagnosis was correctly made in only two patients. The accurate aetiology of endometriosis remains unknown and diagnosis is
based on clinical and cytopathological findings. CONCLUSIONS: Surgical treatment of extraperitoneal endometriosis is recommended.
However, postoperative follow-up is obligatory and hormonal suppressive therapy may be necessary. Medical treatment with gestagens,
Danazol, or agonists of the gonadotropin-releasing hormone are ineffective in endometriomas which are bigger than 2 cm.
相似文献
99.
In-situ forming drug delivery systems are prepared by dissolving a drug and a biodegradable polymer (poly(D,L-lactide-co-glycolide), PLGA) in a biocompatible organic solvent (In-situ implant, ISI) or further emulsified into an external phase (oil or aqueous solution), resulting in oil-in-oil or oil-in-water emulsions (In-situ forming microparticles, ISM). The chemical stability of PLGA and the drug is a major concern. In this study, the stability of PLGA and leuprolide acetate in the in-situ forming systems and lyophilized sponges was investigated. The degradation of PLGA increased with increasing storage temperature and water content in the biocompatible solvents. A faster degradation occurred in polar protic solvents (2-pyrrolidone, PEG 400, triethyl citrate) than in polar aprotic solvents (N-methyl-2-pyrrolidone, DMSO, triacetin, ethyl acetate). The presence of leuprolide acetate significantly accelerated PLGA degradation, especially in solution state. PLGA was stable in oily suspensions at 4 degrees C and degraded only slightly faster than solid powder at 25 degrees C. No interaction between the oils and the PLGA was observed as indicated by an unchanged T(g) of approx. 47 degrees C. PLGA underwent a slight degradation at 4 degrees C after 150 days in water and saturated sodium chloride solution. The degradation was slower in saturated sodium chloride solution than in water at 25 degrees C. Residual acetic acid in lyophilized sponges facilitated the PLGA degradation in contrast to dioxane. Leuprolide acetate did not affect the PLGA stability negatively. However, lidocaine significantly enhanced the polymer degradation in the sponges. Finally, leuprolide acetate was chemically stable in the sponges, the oils and the polymer solutions in suspension state, but unstable (aggregation) when dissolved in the polymer solutions and stored at 25 degrees C and 40 degrees C. 相似文献
100.
K. Jonderko A. Kasicka-jonderko B. Krusiec-świdergoł M. Dzielicki L. Strój M. Doliński K. Doliński B. Błońska-fajfrowska 《Neurogastroenterology and motility》2005,17(6):800-809
AIM: To check on reproducibility of parameters of the cutaneous electrogastrogram registered at a close or a distant time span. METHODS: Twenty-two volunteers recruited by an advertisement (11 females and 11 males, median age 25 years, range: 18-35) underwent three surface electrogastrography examinations of which two were taken on consecutive days and the third one was accomplished at least 2 weeks before or after the two other sessions. The examination involved a 30-min fasted recording, followed by a 90-min postprandial registration after intake of a 394-kcal mixed solid-liquid test meal. RESULTS: Parameters of the electrogastrogram pertaining to the frequency of the gastric slow waves exhibited good to moderate reproducibility, whereas fair reproducibility characterized parameters expected to describe the power of gastric slow waves. With the exception of the difference fed minus fasted power (DeltaDP), in no instance was the medium term reproducibility any worse than the short term one. Categorical data analysis revealed that the relative time share of normogastria postprandially exhibited a better reproducibility than in the fasted period. The Cohen's kappa-value of 0.459 for the DeltaDP for the medium term reproducibility placed this parameter within the range of moderate agreement between repeat examinations. Of the two two-parameter combinations considered, the alliance of the fasted and fed normogastria performed worse than any of those parameters considered alone, whereas a combination of the DeltaDP with the fed-state normogastria revealed a kappa-value amounting to 0.510 for the medium term reproducibility. CONCLUSIONS: The feasibility of some electrogastrographic parameters to convey clinically useful information may be hampered by their fair reproducibility. Recoding of parameters of the cutaneous electrogastrogram from primary continuous to secondary categorical may help achieve a better agreement between repeat examinations. 相似文献