全文获取类型
收费全文 | 7859篇 |
免费 | 321篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 75篇 |
儿科学 | 201篇 |
妇产科学 | 134篇 |
基础医学 | 1494篇 |
口腔科学 | 122篇 |
临床医学 | 640篇 |
内科学 | 1347篇 |
皮肤病学 | 202篇 |
神经病学 | 1040篇 |
特种医学 | 450篇 |
外国民族医学 | 1篇 |
外科学 | 855篇 |
综合类 | 49篇 |
预防医学 | 345篇 |
眼科学 | 128篇 |
药学 | 573篇 |
中国医学 | 11篇 |
肿瘤学 | 539篇 |
出版年
2021年 | 67篇 |
2020年 | 64篇 |
2019年 | 115篇 |
2018年 | 121篇 |
2017年 | 98篇 |
2016年 | 163篇 |
2015年 | 189篇 |
2014年 | 208篇 |
2013年 | 271篇 |
2012年 | 400篇 |
2011年 | 421篇 |
2010年 | 291篇 |
2009年 | 248篇 |
2008年 | 397篇 |
2007年 | 408篇 |
2006年 | 403篇 |
2005年 | 399篇 |
2004年 | 347篇 |
2003年 | 379篇 |
2002年 | 387篇 |
2001年 | 96篇 |
2000年 | 116篇 |
1999年 | 131篇 |
1998年 | 137篇 |
1997年 | 99篇 |
1996年 | 87篇 |
1995年 | 75篇 |
1994年 | 73篇 |
1993年 | 77篇 |
1992年 | 78篇 |
1991年 | 57篇 |
1990年 | 75篇 |
1989年 | 67篇 |
1988年 | 73篇 |
1987年 | 58篇 |
1986年 | 43篇 |
1985年 | 70篇 |
1984年 | 37篇 |
1983年 | 49篇 |
1982年 | 43篇 |
1981年 | 45篇 |
1980年 | 41篇 |
1979年 | 55篇 |
1978年 | 44篇 |
1977年 | 45篇 |
1976年 | 45篇 |
1974年 | 34篇 |
1955年 | 44篇 |
1954年 | 37篇 |
1932年 | 41篇 |
排序方式: 共有8206条查询结果,搜索用时 15 毫秒
11.
Heinz Schurawitzki M.D. Paul C. Hajek Josef Kramer Florian Grabenwöger Walter Klepetko Anton Moritz 《Cardiovascular and interventional radiology》1989,12(1):10-13
In a radiologic search for embolized leaflets of Edwards-Duromedics bileaflet valves in 2 patients, the embolized fragments were localized in the iliac vessels using computed tomography. Sonography was successful in one case and standard X-ray films of the abdomen were negative in both cases.In vitro investigations with Björk-Shiley and Edwards-Duromedics leaflets suggested that standard X-ray films of the abdomen and pelvis should be considered as the first investigational technique. If negative, computed tomography of the lower abdomen should be done. 相似文献
12.
CGP 6809 — A new nitrosoureido-sugar derivative with activity in human tumor xenografts 总被引:1,自引:0,他引:1
Heinz H. Fiebig Karl H. Widmer Bernd R. Winterhalter Georg W. Löhr 《Cancer chemotherapy and pharmacology》1989,23(6):337-340
Summary CGP 6809 [ethyl-6-deoxy-3,5-di-O-methyl-6-(3-methyl-3-nitrosoureido)--d-glucofuranoside] is a new methylnitrosoureido-sugar derivative that has been shown to be active against a broad spectrum of transplantable tumours in mice and rats [14]. We investigated the anti-tumour effect of CGP 6809 in ten selected, human tumour xenograft lines growing s. c. in nude mice. The p. o. administration of 125 mg/kg per day for 10–15 days was less toxic (lethality 12% in tumour-bearing nude mice) than the i. p. injection of 62.5 mg/kg per day (lethality 22%). The anti-tumour effect was similar for both application routes; two large bowel cancers responded to treatment with CGP 6809, rectal cancer CXF 158 showed a remission, and the rapidly growing, undifferentiated colonic cancer CXF 280 exhibited a transient no-change. Furthermore, remissions were observed in the epidermoid lung cancer LXF 322 and in thyroid cancer 117. Tumour progression was found in another epidermoid lung cancer and in three stomach cancers, one melanoma, and one soft tissure sarcoma. CGP 6809 is a promising new agent for clinical trials, especially for large bowel and epidermoid lung cancer.Supported in part by grant PTB 8467 from the Bundesminister für Forschung und Technologie, Bonn, FRG 相似文献
13.
Exchange diffusion of chloride in frog gastric mucosa 总被引:2,自引:0,他引:2
Durbin R. P.; Kitahara S.; Stahlmann K.; Heinz E. 《The American journal of physiology》1964,207(6):1177-1180
14.
Eisele M Heukelbach J Van Marck E Mehlhorn H Meckes O Franck S Feldmeier H 《Parasitology research》2003,90(2):87-99
Tungiasis is an important health problem in poor communities in Brazil and is associated with severe morbidity, particularly in children. The causative agent, the female flea Tunga penetrans, burrows into the skin of its host, where it develops, produces eggs and eventually dies. From the beginning of the penetration to the elimination of the carcass of the ectoparasite by skin repair mechanisms, the whole process takes 4-6 weeks. The present study is based on specimens from 86 patients, for some of whom the exact time of penetration was known. Lesions were photographed, described in detail and biopsied. Biopsies were examined histologically and by means of scanning electron microscopy (SEM). Based on clinical, SEM and histological findings, the "Fortaleza classification" was elaborated. This allows the natural history of tungiasis to be divided into five stages: (1) the penetration phase, (2) the phase of beginning hypertrophy, (3) the white halo phase, (4) the involution phase and (5) residues in the host's skin. Based on morphological and functional criteria, stages 3 and 4 are divided into further substages. The proposed Fortaleza classification can be used for clinical and epidemiological purposes. It allows a more precise diagnosis, enables the assessment of chemotherapeutic approaches and helps to evaluate control measures at the community level. 相似文献
15.
16.
17.
18.
Biological and clinical significance of cytogenetic abnormalities in low-risk and high-risk gastrointestinal stromal tumors 总被引:3,自引:0,他引:3
Gunawan B Bergmann F Höer J Langer C Schumpelick V Becker H Füzesi L 《Human pathology》2002,33(3):316-321
We report cytogenetic findings in 19 c-Kit-positive gastrointestinal stromal tumors (GISTs) that represent a heterogenous group of mesenchymal neoplasms with respect to site, histology, and biologic behavior. All of the GISTs (5 low-risk, 11 high-risk, 3 recurrences) displayed clonal chromosomal aberrations; 15 were hypo- to near-diploid, and 4 were near-triploid and hypotetraploid. The most common abnormalities were loss of chromosomes 14 and/or 22, demonstrated in 14 GISTs irrespective of site or predominant phenotype. Ten cases (2 low-risk, 5 high-risk, 3 recurrences) were characterized by loss of both chromosomes 14 and 22, 2 cases (1 low-risk, 1 high- risk), by loss of chromosome 14; and 2 high-risk cases, by loss of chromosome 22. Additional chromosomal aberrations occurred preferentially in high-risk and recurrent GISTs, including loss of 9p and 1p in 8 cases each, loss of 15 in 6 cases, loss of 3p in 5 cases, loss of 13q and 10q in 4 cases each, loss of 19 in 3 cases, and complete or partial gains of chromosomes 5 and 4 in 2 cases each. More significantly, 5 of 6 patients with clinically aggressive GISTs, including 2 recurrences and 3 metastasing GISTs, were additionally characterized by loss of 9p; four of these had additional loss of chromosomes 1p and 15. The presented results herein indicate that loss of chromosome 14 and/or 22 is an early change in GIST tumorigenesis irrespective of site or differentiation, whereas malignant transformation and progression of GISTs appear to be associated with an increasing incidence of additional secondary aberrations. 相似文献
19.
Gordon Lauc Annie-Pierre Seve Jean Hubert Mirna Flgel-Mrsic Werner E. G. Müller Heinz C. Schrder 《Mechanisms of ageing and development》1993,70(3):227-236
Previous studies have demonstrated the existence of nuclear carbohydrate binding proteins in a variety of mammalian cells with molecular masses of 35 000, 67 000, and 70 000 (CBP35, CBP67, and CBP70), which are associated with nuclear ribonucleoprotein (RNP) complexes. CBP35 consists of two domains, an aminoterminal portion that is homologous to certain regions of proteins of the heterogeneous nuclear RNP complex, and a carboxyl-terminal portion homologous to β-galactoside-specific lectins. CBP35 it has been proposed, like the glucose-specific lectin, CBP67, to guide RNP complexes through the nuclear pore. Here we show that the exposure of mature rats to stress induces an increase in nuclear CBP35 bound to CBP67 and retained on immobilized glucose. Nuclear extracts from the livers of old rats displayed no detectable stress response. This CBP35·CBP67 association detected in rat liver is considered with respect to the CBP35·CBP70 association recently observed in HL60 cell nuclear extracts. 相似文献
20.
Schwerer MJ Hemmer J Kraft K Maier H Möller P Barth TF 《Virchows Archiv : an international journal of pathology》2003,443(1):98-103
We report the case of a 58-year-old man who presented with a squamous cell carcinoma pT1a G2 of the left vocal cord. Six months after histologically verified complete resection, the patient experienced an endolaryngeal and extralaryngeal local recurrence pT4 pN2b G2. We applied DNA flow cytometry (FCM) and comparative genomic hybridization (CGH) on both primary and recurrent tumor. The primary tumor and the endolaryngeal compartment of the relapse was an aneuploid cell clone with a FCM DNA index of 1.42 and 1.44, respectively. The extralaryngeal compartment showed a shift featuring a DNA index of 2.78. In the primary tumor and in both compartments of the recurrence there was an identical pattern of complex chromosomal imbalances as detected in CGH (CGH karyotype: rev ish enh [8q24.2-q24.3, 10q26.1-q26.3, 11q24-q25, 12q24.2-q23.33,X], dim [4q, 13q14.3-q31], amp[1p36.1-p36.2]). Hence, the recurrence was not associated with further gains and losses of chromosomal material. However, in the anterior part of the recurrence, the aneuploid tumor cell genome had completely doubled, obviously due to endoreduplication. Immunohistochemical analysis of several cell-cycle regulators revealed altered expression of checkpoint proteins, pointing to a complex disturbance in cell-cycle regulation. 相似文献