全文获取类型
收费全文 | 196479篇 |
免费 | 7908篇 |
国内免费 | 466篇 |
专业分类
耳鼻咽喉 | 2571篇 |
儿科学 | 5696篇 |
妇产科学 | 4456篇 |
基础医学 | 27989篇 |
口腔科学 | 6221篇 |
临床医学 | 11522篇 |
内科学 | 44360篇 |
皮肤病学 | 5417篇 |
神经病学 | 16010篇 |
特种医学 | 4810篇 |
外国民族医学 | 1篇 |
外科学 | 23293篇 |
综合类 | 937篇 |
一般理论 | 38篇 |
预防医学 | 22414篇 |
眼科学 | 5195篇 |
药学 | 14797篇 |
中国医学 | 806篇 |
肿瘤学 | 8320篇 |
出版年
2023年 | 1019篇 |
2022年 | 1001篇 |
2021年 | 3484篇 |
2020年 | 1848篇 |
2019年 | 3733篇 |
2018年 | 6151篇 |
2017年 | 3787篇 |
2016年 | 3767篇 |
2015年 | 4060篇 |
2014年 | 4819篇 |
2013年 | 7242篇 |
2012年 | 12488篇 |
2011年 | 13240篇 |
2010年 | 6595篇 |
2009年 | 4819篇 |
2008年 | 10789篇 |
2007年 | 11463篇 |
2006年 | 10833篇 |
2005年 | 10456篇 |
2004年 | 9692篇 |
2003年 | 9080篇 |
2002年 | 8598篇 |
2001年 | 5815篇 |
2000年 | 6654篇 |
1999年 | 4821篇 |
1998年 | 983篇 |
1992年 | 2331篇 |
1991年 | 2097篇 |
1990年 | 2058篇 |
1989年 | 1776篇 |
1988年 | 1676篇 |
1987年 | 1583篇 |
1986年 | 1609篇 |
1985年 | 1508篇 |
1984年 | 1097篇 |
1983年 | 956篇 |
1979年 | 1238篇 |
1978年 | 835篇 |
1977年 | 815篇 |
1976年 | 765篇 |
1975年 | 908篇 |
1974年 | 1140篇 |
1973年 | 1183篇 |
1972年 | 1116篇 |
1971年 | 1096篇 |
1970年 | 1023篇 |
1969年 | 1095篇 |
1968年 | 1117篇 |
1967年 | 991篇 |
1966年 | 891篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
E García-Gómez S Vaca A Pérez-Méndez J Ibarra-Caballero V Pérez-Márquez V R Tenorio E Negrete-Abascal 《Avian pathology》2005,34(5):426-429
Gallibacterium anatis (previously named Pasteurella haemolytica-like) is considered a normal inhabitant of genital and upper respiratory tracts of healthy chickens, but it is also associated with different pathological conditions. Secreted metalloproteases from field and reference G. anatis cultures were obtained by methanol precipitation and were characterized. Proteins of molecular mass higher than 100 kDa showing proteolytic activity were observed in 10% polyacrylamide gels copolymerized with 1% bovine casein. They were active at alkaline pH, and inhibited by ethylenediamine tetraacetic acid. Their activity was stable at 50 degrees C, but partially inhibited at 60 degrees C, and totally inhibited at higher temperatures. Secreted proteins were able to degrade chicken IgG after 24 h of incubation, and cross-reacted with a polyclonal antibody against purified protease from Actinobacillus pleuropneumoniae. Secreted metalloproteases could play a role in infections caused by G. anatis. 相似文献
32.
33.
Raúl González-García Francisco J Rodríguez-Campo Verónica Escorial-Hernández Mario F Mu?oz-Guerra Jesús Sastre-Pérez Luis Naval-Gías José L Gil-Díez Usandizaga 《Journal of oral and maxillofacial surgery》2006,64(11):1587-1591
PURPOSE: Temporomandibular joint (TMJ) arthroscopy has been considered a safe surgical procedure in the treatment of TMJ derangement. However, it is not exempt from complications. This study evaluates the complications of arthroscopy in patients with internal derangement of TMJ. PATIENTS AND METHODS: Five hundred consecutive patients (670 joints) with TMJ derangement who underwent arthroscopy between 1995 and 2004 were retrospectively analyzed. All the patients were classified as II to V in the Wilkes classification. Lysis and lavage, electrocautery of the posterior ligament, injection of corticoids, injection of ethanolamine, myotomy of lateral pterygoid muscle attachments, myotomy and electrocautery, motor debridement, injection of sodium hyaluronate, and meniscal suture were performed in different patients. RESULTS: Complications were recognized during or immediately after the surgery. They were observed in 5 of 341 (1.26%) arthroscopies of the right TMJ and 4 of 329 (1.21%) arthroscopies of the left TMJ. A 1.34% complication rate was found in the whole series. No blood clots within the external auditory canal were observed. Bleeding within the superior TMJ space was observed in 57 cases (8.5%), 36 of them in the right TMJ and 21 in the left TMJ, but they were not considered as true complications. Lacerations of the external auditory canal were found in 2 cases (0.3%), with no cases of perforation of the tympanic membrane. Lesion of the auriculotemporal nerve was observed in a case. Paresia of the facial nerve was found in 4 cases (0.6%). Alteration of visual accuracy of the ipsilateral eye was also observed in a patient immediately after the surgery. CONCLUSION: Special care must be taken to reduce complications within the upper joint space by means of an adequate instrumentation and by paying attention to essential points of the arthroscopic technique. 相似文献
34.
This study presents the case of a patient with necrobiosis or necrosing fascitis of the inguinal region, secondary to a complicated
Amyand’s hernia with a concomitant ipsilateral Richter’s hernia. The patient was treated with open trans-abdominal surgery
and hernia repair through the pre-peritoneal approach, plus anti-microbians, and thrice-daily wound cleansing and dressings
to the inguinal region. Evolution was satisfactory. There are no reports in the literature of a case such as this. 相似文献
35.
36.
37.
38.
39.
L. Unghváry 《Journal of molecular medicine (Berlin, Germany)》1941,20(18):449-453
Zusammenfassung
Die bogenförmige ST-Strecke kommt häufig, in etwa 12%der Fälle, und die Zwischenzacke selten, in 5der Fälle eines nichtausgewählten Krankenmaterials, vor. Sowohl die Entstehungsursache der bogenförmigen ST-Strecke als der Kischschen Zwischenzacke liegt in der stärkeren oder schwächeren Rechts- oder Linksdeviation der S-Achse. Die Richtung und der Grad der S-Achsendeviation wird es also bestimmen, in wie vielen und welcher Einthovenschen Ableitung die bogenförmige ST-Strecke bzw. die Zwischenzacke notwendigerweise auftreten muß. Bei S-Achsenstellungen zwischen –90°und –30°wird die ST-Strecke in Ableitung I, bei S-Achsenstellungen zwischen –30°und +30°in der I. und II., zwischen +30°und +90°in der I., II., III., zwischen +90°und +150°in der II., III. und bei den Achsenstellungen zwischen +150°und –150°in der III. Einthovenschen Ableitung bogenförmig sein. Die klinische Bedeutung der bogenförmigen ST-Strecke ist gleich mit der klinischen Bedeutung der S-Achsendeviation. Bei dem Vergleich des Herzbefundes der Kranken mit der elektrischen S-Achsenstellung können folgende Feststellungen gemacht werden: Geringergradige Linksdeviation der S-Achse, d. h. bogenförmiges ST
I sowie geringergradige Rechtsdeviation der S-Achse, d. h. STIII kann praktisch bei pathologischem Herzbefund nicht verwertet werden. Stärkere Links- bzw. Rechtsdeviation der S-Achse, d. h. STI undII bzw. STII undIII können im allgemeinen ebenfalls nicht verwertet werden, es ist jedoch wahrscheinlich, daß sie schon einen Übergang zu den pathologischen Befunden bilden. Während jene starken S-Achsendeviationen, wo schon in allen drei Ableitungen bogenförmiges ST besteht, meistens für das Zeichen der myokardialen Läsion betrachtet werden sollen, und zwar in erster Linie dann, wenn die positive S-Zacke in oder neben dem absteigenden Schenkel der R-Zacke gut wahrnehmbar ist. 相似文献
40.
B Bonet M Viana I Sánchez-Vera A Quintanar J Martínez M Espino 《Diabetic medicine》2007,24(11):1192-1198
AIMS: The aims of our study were to determine if insulin resistance is associated with increased plasma levels of non-esterified fatty acids (NEFA), glycerol, 3-hydroxybutyrate and triglycerides in obese children. We also studied whether the presence of acanthosis nigricans (AN) led to further alterations in the above parameters. METHODS: A total of 101 children were studied on their first visit to the paediatric endocrine clinic. Seventy-four were obese, 30 of them with AN. The remaining 27 were non-obese healthy children (control group). NEFAs, glycerol, triglycerides, 3-hydroxybutyrate, insulin, leptin, adiponectin and glucose were determined in blood samples obtained after overnight fasting. The insulin resistance index (IRI) was calculated following the homeostasis model assessment (HOMA). Data from the three groups were compared using appropriate statistical tests. RESULTS: No differences in age, sex ratio and pubertal stage were observed among the three groups. The group of children with the highest body mass index (BMI) showed higher plasma levels of insulin and leptin, higher IRI and lower plasma levels of adiponectin. As insulin and IRI increased, NEFA and 3-hydroxybutyrate decreased and triglycerides increased. When obese children were categorized by BMI, the presence of AN further exacerbated these differences. CONCLUSIONS: In obese children, insulin resistance is associated with plasma lipid alterations suggestive of both decreased adipose tissue lipolysis and hepatic beta-oxidation and increased hepatic synthesis of triglycerides. Such a metabolic condition may facilitate fat storage and hinder weight loss. 相似文献