全文获取类型
收费全文 | 22116篇 |
免费 | 1002篇 |
国内免费 | 168篇 |
专业分类
耳鼻咽喉 | 254篇 |
儿科学 | 378篇 |
妇产科学 | 337篇 |
基础医学 | 3268篇 |
口腔科学 | 356篇 |
临床医学 | 1975篇 |
内科学 | 4207篇 |
皮肤病学 | 716篇 |
神经病学 | 2717篇 |
特种医学 | 1201篇 |
外科学 | 2769篇 |
综合类 | 154篇 |
一般理论 | 6篇 |
预防医学 | 951篇 |
眼科学 | 505篇 |
药学 | 1772篇 |
中国医学 | 28篇 |
肿瘤学 | 1692篇 |
出版年
2023年 | 95篇 |
2022年 | 155篇 |
2021年 | 277篇 |
2020年 | 233篇 |
2019年 | 280篇 |
2018年 | 374篇 |
2017年 | 296篇 |
2016年 | 421篇 |
2015年 | 465篇 |
2014年 | 657篇 |
2013年 | 823篇 |
2012年 | 1291篇 |
2011年 | 1381篇 |
2010年 | 778篇 |
2009年 | 794篇 |
2008年 | 1434篇 |
2007年 | 1485篇 |
2006年 | 1562篇 |
2005年 | 1584篇 |
2004年 | 1447篇 |
2003年 | 1479篇 |
2002年 | 1396篇 |
2001年 | 264篇 |
2000年 | 212篇 |
1999年 | 295篇 |
1998年 | 326篇 |
1997年 | 270篇 |
1996年 | 214篇 |
1995年 | 175篇 |
1994年 | 196篇 |
1993年 | 149篇 |
1992年 | 108篇 |
1991年 | 129篇 |
1990年 | 127篇 |
1989年 | 104篇 |
1988年 | 107篇 |
1987年 | 72篇 |
1986年 | 70篇 |
1985年 | 83篇 |
1984年 | 95篇 |
1983年 | 83篇 |
1982年 | 85篇 |
1981年 | 98篇 |
1980年 | 73篇 |
1979年 | 70篇 |
1978年 | 53篇 |
1977年 | 64篇 |
1976年 | 71篇 |
1974年 | 59篇 |
1955年 | 48篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
Rongnong Zhou Ligong Tang Kurt E. Geckeler Wolfgang Gpel 《Macromolecular chemistry and physics.》1994,195(7):2409-2421
Polystyrene-bound metal [2,9 or 2,10 (or 2,16 or 2,17) bis(3,4-dicarboxybenzoyl)]phthalocyaninates were synthesized by Friedel-Crafts reaction of polystyrene with the corresponding metal phthalocyaninates. Co(II) and Cu(II) [2,9 or 2,10 (or 2,16 or 2,17) bis(3,4-dicarboxybenzoyl)]-phthalocyaninate (PS-CodaPc and PS-CudaPc) contained 0,13 mmol · g?1 (12,4 wt.-%) and 0,13 mmol · g?1 (12,8 wt.-%) of CodaPc and CudaPc, respectively. They were soluble in N,N'-dimethylformamide, but only partially soluble in chloroform, tetrahydrofuran (THF), dimethyl sulfoxide, N-methyl-2-pyrrolidone, and pyridine. The THF extracts contained 0,12 mmol · g?1 (11,4 wt.-%) and 0,18 mmol ? g?1 (17,2 wt.-%) of PS-CodaPc and PS-CudaPc, respectively. The thermal stability of the polymers was studied using thermogravimetric and differential thermal analysis in nitrogen and synthetic air atmosphere. The contents of MdaPc(M: metal) in THF-extracted polymers calculated from the data of residue in thermogravimetric analysis are 0,12 mmol · g?1 for PS-CodaPc and 0,19 mmol · g?1 for PS-CudaPc. In addition, the sensitive properties of the polymers towards toxic gases were also investigated by quartz microbalance transducers. The results show that the quartz microbalance sensors coated with both polymers were sensitive to NO2 and chlorinated hydrocarbons, i.e. chloroform and perchloroethylene. The sensitivity to NO2 was 6,53 · 10?7 m3 · mL?1 · s?1 for PS-CodaPc and 1,90 · 10?6 m3 · mL?1 · s?1 for PS-CudaPc, and that to chloroform and perchloroethylene was 2,33 · 10?8 and 4,60 · 10?8 m3 · mL?1 · s?1, respectively, for PS-CodaPc and 4,79 · 10?8 and 9,51 · 10?7 m3 · mL?1 · s?1 for PS-CudaPc. 相似文献
52.
Winfried Rief Sylvia Schaefer Wolfgang Hiller Manfred M. Fichter 《European archives of psychiatry and clinical neuroscience》1992,241(4):236-240
Thirty inpatients with somatoform disorders were examined with the structured clinical interview SCID for psychiatric lifetime diagnosis. In the present diagnoses, we found a concordance of 63% for somatoform and affective disorders and the lifetime comorbidity of both disorders was 87%. Additionally, patients with somatoform disorders frequently had a history of other psychiatric disorders (for example, anxiety disorders, 40%). For 73% of patients with somatoform disorders and a history of affective disorders, the onset of the somatoform disorder was prior to the onset of another psychiatric disorder. The time interval between the onsets of somatoform disorders and affective disorders was greater than 1 year for most patients; for 46% of the patients with a history of both disorders, the time interval between the two disorders was more than 5 years. The course of illness for somatoform and affective disorders was quite different; while affective disorders tended to episodic periods with interim remissions, the somatoform disorders usually showed long, chronic courses (mean duration of the current somatoform disorder was 11.9 years). Finally, the Symptom Check List SCL-90R demonstrated good discrimination between patients with affective and anxiety disorders. However, the SCL-90R failed to discriminate patients with somatoform disorders from affective- and anxiety-disordered subjects. Therefore, the development of other psychometric scales is necessary for the evaluation of patients with somatoform disorders. 相似文献
53.
Rainer Pankau Carl-Joachim Partsch Johannes Funda Wolfgang Günther Sippell 《American journal of medical genetics. Part A》1992,43(3):513-516
We report on the hypothalamic-pituitary-gonadal function in 2 male infants with the Smith-Lemli-Opitz (SLO or RSH) syndrome. Both infants had abnormal external genitalia. Basal and LHRH stimulated plasma gonadotropins were normal for age (1 month). Plasma testosterone, androstenedione, and dehydroepiandrosterone sulfate were normal for age and sex. Some forms of congenital adrenal hyperplasia (17,20-desmolase deficiency, 17α-hydroxylase deficiency, and 3β-hydroxysteroid dehydrogenase deficiency) were ruled out by hormonal studies. The endocrinological findings indicate a normal hypothalamic-pituitary-gonadal function and a normal adrenal steroid biosynthesis in these 2 patients. A partial androgen receptor defect causing the genital malformations seems possible in one patient. Whether 5α-reductase deficiency is the cause of the male pseudohermaphroditism in SLO syndrome remains the subject of future studies. © 1992 Wiley-Liss, Inc. 相似文献
54.
55.
We evaluated the function of the supraspinatus tendon with a dynamic shoulder model. Active glenohumeral joint motion was simulated in 10 cadaveric shoulder specimens with hydrodynamic cylinder forces at the deltoid muscle and at the rotator cuff. Computerized regulation initiated standardized cycles of glenohumeral joint motion, where the isolated effect of the supraspinatus muscle could be studied. The efficacy of the supraspinatus muscle on elevation of the glenohumeral joint was measured with an ultrasonic sensor system. Pressures underneath the coracoa-cromial vault were recorded with capacitive sensors, as an indicator of the impingement at the shoulder. Elimination of force of the supraspinatus muscle led to a 6 percent decrease in elevation of the glenohumeral joint. The deltoid muscle was able to reverse this loss of elevation by a force increase of one third of the lost supraspinatus force. If no force was applied to the supraspinatus muscle, average pressures underneath the coracoacromial vault decreased 8 percent. It was concluded that the supraspinatus produces less torque and more glenohumeral joint compression than the deltoid. However, the supraspinatus has no effect on depression of the humeral head during elevation.
The clinical consequence of our observations is that operative closure of supraspinatus tendon defects is not mandatory. 相似文献
The clinical consequence of our observations is that operative closure of supraspinatus tendon defects is not mandatory. 相似文献
56.
57.
58.
Dr. med. Wolfgang Ludewig 《International archives of occupational and environmental health》1941,11(2):296-310
Ohne ZusammenfassungDie einzelnen Befunde wurden auf Schwert-Karte DIN A 5 Nr. 24 988 festgelegt.Am Schlusse der Arbeit crlaube ich mir, dem Herrn Reichsarbeitsminister für die Bereitstellung der erforderlichen Mittel ergebenst zu danken. 相似文献
59.
Johannes M. Mayr Wolfgang Grechenig Michael E. Höllwarth 《European Journal of Trauma》2004,30(3):150-160
Abstract
Background and Purpose:
The radiologic evaluation of musculoskeletal injuries in young children is difficult due to the absent ossification of several secondary ossification centers, which therefore cannot be seen directly on plain radiographs. When relying on conventional radiographs, even severe cartilaginous or soft tissue injuries cannot be visualized, as there is no possibility to differentiate them from bruises or sprains. It is the aim of this review to present clinically relevant applications of ultrasound imaging in pediatric musculoskeletal trauma.
Methods:
Currently used ultrasound techniques for evaluation of typical pediatric fractures or joint dislocations, techniques for differentiation between stable and unstable intraarticular fractures, the use of sonography for monitoring reduced bone length in long bones after fracture, sonographic guidelines for evaluation of tendon injuries or lesions, and sonographic imaging techniques in arthritis and osteomyelitis are described.
Conclusion:
Musculoskeletal sonography—despite its inability to view through intact cortical bone and its accuracy being dependent on skill and experience of the investigator—provides important information about soft tissue, bony or cartilaginous injuries in children. 相似文献
60.
Ingmar Königsrainer Wolfgang Steurer Maria Witte Alfred Königsrainer 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(4):485-488
Background Nowadays, liver resection is a routine operative procedure in surgical centers, and strategies must be aimed at avoiding additional
risk factors. Extrahepatic isolation of portal vein, hepatic artery and hepatic duct, as well as lymphadenectomy of the liver
hilum are generally accepted steps of liver resection, even for metastatic and benign indications. Our primary aim was to
analyze the feasibility, blood loss, blood transfusion requirements, incidence of complications, and outcome using the approach
for intrahepatic devascularization leaving the extrahepatic hilus untouched.
Materials and methods Thirty-eight consecutive patients with resection for metastases and benign liver tumors were selected. After hilar examination,
the extrahepatic structures remain intact, and during parenchyma dissection, the whole right or left or the appropriate bi-segmental
pedicle is isolated intrahepatically and then transected using a stapler device.
Results The used technique was feasible in all cases, and no intra- or postoperative surgical complications were observed. To date,
no tumor recurrence was found in the hilum during the follow-up period.
Conclusion The intrahepatic pedicle stapling technique appears to be feasible and safe in liver resection. Hilar dissection can, thus,
be avoided in liver metastasis and benign liver tumors. 相似文献