全文获取类型
收费全文 | 11300篇 |
免费 | 465篇 |
国内免费 | 136篇 |
专业分类
耳鼻咽喉 | 84篇 |
儿科学 | 166篇 |
妇产科学 | 155篇 |
基础医学 | 1262篇 |
口腔科学 | 329篇 |
临床医学 | 737篇 |
内科学 | 3026篇 |
皮肤病学 | 172篇 |
神经病学 | 735篇 |
特种医学 | 443篇 |
外科学 | 2352篇 |
综合类 | 39篇 |
预防医学 | 242篇 |
眼科学 | 134篇 |
药学 | 644篇 |
中国医学 | 19篇 |
肿瘤学 | 1362篇 |
出版年
2023年 | 85篇 |
2022年 | 163篇 |
2021年 | 305篇 |
2020年 | 176篇 |
2019年 | 192篇 |
2018年 | 240篇 |
2017年 | 197篇 |
2016年 | 261篇 |
2015年 | 262篇 |
2014年 | 383篇 |
2013年 | 466篇 |
2012年 | 716篇 |
2011年 | 755篇 |
2010年 | 414篇 |
2009年 | 374篇 |
2008年 | 655篇 |
2007年 | 692篇 |
2006年 | 683篇 |
2005年 | 752篇 |
2004年 | 732篇 |
2003年 | 680篇 |
2002年 | 670篇 |
2001年 | 159篇 |
2000年 | 157篇 |
1999年 | 188篇 |
1998年 | 187篇 |
1997年 | 134篇 |
1996年 | 129篇 |
1995年 | 96篇 |
1994年 | 85篇 |
1993年 | 86篇 |
1992年 | 85篇 |
1991年 | 81篇 |
1990年 | 64篇 |
1989年 | 86篇 |
1988年 | 63篇 |
1987年 | 58篇 |
1986年 | 47篇 |
1985年 | 45篇 |
1984年 | 39篇 |
1983年 | 47篇 |
1982年 | 22篇 |
1981年 | 18篇 |
1980年 | 21篇 |
1979年 | 29篇 |
1978年 | 23篇 |
1977年 | 13篇 |
1976年 | 12篇 |
1975年 | 12篇 |
1969年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
31.
32.
Yoshiro Tanizaki Hikaru Kitani Takashi Mifune Fumihiro Mitsunobu Kazuhiro Kajimoto Keisuke Sugimoto 《The Journal of asthma》1993,30(6):485-492
The effects of glucocorticoids on the proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid in relation to humoral and cellular immunity were studied in 56 patients with steroid-dependent intractable asthma. To analyze the mechanism responsible for reduced numbers of BAL lymphocytes, we divided the subjects into 4 groups according to their BAL lymphocyte proportions: 0—4.9%, 5.0-9.9%, 10.0-14.9%, and 15.0-20.0%. Serum IgG levels and the peripheral lymphocyte count were significantly reduced in patients with a low proportion of BAL lymphocytes (less than 9.9%) than in those with more than 10% BAL lymphocytes. Delayed cutaneous reactivity to purified protein derivative was suppressed in patients with a low proportion of BAL lymphocytes (less than 4.9%). The mean proportion of BAL neutrophils tended to increase as the proportion of BAL lymphocytes decreased. These results show that the reduction in BAL lymphocytes produced by glucocorticoids is associated with suppressed humoral and cellular immunity, and that under such conditions the proportion of BAL neutrophils increases. 相似文献
33.
34.
Spondylolysis after posterior decompression of the lumbar spine: 35 patients followed for 3-9 years 总被引:5,自引:0,他引:5
Radiographs were examined in 35 patients who had had posterior decompression without fusion of the lumbar spine. Spondylolysis was found in 10 patients. Segmental range of motion, degree of vertebral slippage and width of decompression were analyzed by radiography. There was greater vertebral slippage after surgery in patients with postoperative spondylolysis than in those without spondylolysis. We conclude that excessive bony decompression may cause postoperative spondylolysis. 相似文献
35.
Y Fukuda N Yamanaka M Ishizaki T Suzuki Y Masugi G Yajima T Nagata 《Acta pathologica japonica》1982,32(2):361-370
An autopsy case of what was clinically considered to be Goodpasture's syndrome was investigated. The lung had hemorrhagic interstitial pneumonia, showing granular patterns of IgG and C3 along the alveoli by the immunofluorescent method and electron-dense subepithelial deposits by electron microscopy. The kidney had crescentic and segmental necrotizing glomerulonephritis associated with membranous nephropathy. Uneven, continuous patterns of immunofluorescent IgG and C3 along the GBM were noted. Electron microscopy showed numerous subepithelial deposits, and immunoelectron microscopy revealed that IgG was not present in the GBM itself but present in the subepithelial deposits. Anti-GBM antibody activity was not detected in the serum or the kidney eluate. It was suggested that renal and pulmonary lesions occurred through the same mechanism and in association with immune deposits. We propose that there is a disease having immune complex-mediated deposits. We propose that there is a disease having immune complex-mediated renal and pulmonary lesions which clinically resembles the conventional Goodpasture's syndrome. 相似文献
36.
Association of the insertion/deletion polymorphism of the angiotensin I-converting enzyme gene in patients of migraine with aura 总被引:2,自引:0,他引:2
Kowa H Fusayasu E Ijiri T Ishizaki K Yasui K Nakaso K Kusumi M Takeshima T Nakashima K 《Neuroscience letters》2005,374(2):129-131
Recently, several angiotensin I-converting enzyme (ACE) inhibitors and an angiotensin II receptor blocker were demonstrated to have a clinically important prophylactic effect in migraine. ACE is one of the key enzymes in the rennin-angiotensin-aldosterone system, which modulates vascular tension and blood pressure. In humans, serum ACE levels are strongly genetically determined. Individuals who were homozygous for the deletion (D) allele showed increased ACE activity levels. To investigate the role of ACE polymorphism in headache, we analyzed the ACE insertion (I)/deletion (D) genotypes of 54 patients suffering from migraine with aura (MwA), 122 from migraine without aura, 78 from tension-type headache (TH), and 248 non-headache healthy controls. The ACE D allele were significantly more frequent in the MwA than controls (p<0.01). The incidence of the D/D genotype in MwA (25.9%) was significantly higher than that in controls (12.5%; p<0.01; odds ratio=5.26, 95% confidence interval: 1.69-16.34, adjusted for age and gender). No differences in the remaining groups were found. Our results support the conclusion that the D allele and the D/D genotype in the ACE gene is a genetic risk factor for Japanese MwA. There seems to be a possible relationship between ACE activity and the pathogenesis of migraine. 相似文献
37.
Koichiro Yuji Shigesaburo Miyakoshi Daisuke Kato Yuji Miura Tomohiro Myojo Naoko Murashige Yukiko Kishi Kazuhiro Kobayashi Eiji Kusumi Hiroto Narimatsu Tamae Hamaki Tomoko Matsumura Masahiro Kami Takahiro Fukuda Shigeru Masuo Kazuhiro Masuoka Atsushi Wake Junichi Ueyama Akiko Yoneyama Ko Miyamoto Haruhisa Nagoshi Michio Matsuzaki Shinichi Morinaga Yoshitomo Muto Yoichi Takeue Shuichi Taniguchi 《Biology of blood and marrow transplantation》2005,11(4):314-318
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor. 相似文献
38.
Contribution of redox-active iron and copper to oxidative damage in Alzheimer disease 总被引:1,自引:0,他引:1
Castellani RJ Honda K Zhu X Cash AD Nunomura A Perry G Smith MA 《Ageing research reviews》2004,3(3):319-326
Metal-catalyzed hydroxyl radicals are potent mediators of cellular injury, affecting every category of macromolecule, and are central to the oxidative injury hypothesis of Alzheimer disease (AD) pathogenesis. Studies on redox-competent copper and iron indicate that redox activity in AD resides exclusively within the neuronal cytosol and that chelation with deferoxamine, DTPA, or, more recently, iodochlorhydroxyquin, removes this activity. We have also found that while proteins that accumulate in AD possess metal-binding sites, metal-associated cellular redox activity is primarily dependent on metals associated with nucleic acid, specifically cytoplasmic RNA. These findings indicate aberrations in iron homeostasis that, we suspect, arise primarily from heme, since heme oxygenase-1, an enzyme that catalyzes the conversion of heme to iron and biliverdin, is increased in AD, and mitochondria, since mitochondria turnover, mitochondrial DNA, and cytochrome C oxidative activity are all increased in AD. These findings, as well as studies demonstrating a reduction in microtubule density in AD neurons, suggest that mitochondrial dysfunction, acting in concert with cytoskeletal pathology, serves to increase redox-active heavy metals and initiates a cascade of abnormal events culminating in AD pathology. 相似文献
39.
Endo K 《Rinsho byori. The Japanese journal of clinical pathology》2004,52(9):759-766
The recent methodological advances in molecular biology, immunology, and genetics have clarified neuroimmunological problems in axonal Guillain-Barré syndrome, seronegative myasthenia gravis, paraneoplastic neurologic syndromes and many others. In addition to clinical and serological studies in peripheral neuropathies, the origins and measurement of anti-ganglioside antibodies and relationships to similar carbohydrate structures on infectious organisms are discussed in the context of molecular mimicry hypothesis, especially related with both the localization of relevant gangliosides in the nerve and clinical phenotypes. Major advances have been made in animal modeling of anti-ganglioside antibody-associated disease. An explanation for muscular weakness in 10-15% of patients with seronegative myasthenia gravis who lack autoantibodies to acetylcholine receptors(AchRs) appears to be the autoantibodies to muscle-specific receptor tyrosine kinase (MuSK). MuSK mediates agrin-induced clustering of AchRs during synapse formation. These autoantibodies to the extracellular domain of MuSK inhibit its function in tissue culture. Isoelectric focusing (IEF) and agar gel electrophoresis (AGE) are used to examine cerebrospinal fluid (CSF) and sera from patients with multiple sclerosis (MS). The CSF oligoclonal IgG bands (OB) are less frequently observed in Japanese MS patients compared with Caucasian patients. Few optic-spinal form of MS (OS-MS) was positive for OB by agarose gel electrophoresis, but IEF is more sensitive than AGE. Recent IEF data revealed some OS-MS patients were positive for OB. The neuroimmunological advances revealed the relationship between the neuroimmunological diseases and the putative autoantibodies as diagnostic markers, for example, HAM and hnRNP-A1, MSand anti-hnRNP-B1 antibody, opsoclonus-myoclonus syndrome and anti-GluRdelta2 antibody, Rasmussen encephalitis and anti-GluR3 antibody, paraneoplastic brainstem encephalitis and anti-Ma2 antibody, and so on. 相似文献
40.
Suzuki A Nozawa-Inoue K Ikeda N Amizuka N Ono K Takagi R Maeda T 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,286(2):908-916
Previous developmental studies on the temporomandibular joint (TMJ) have proposed several hypotheses on the formation of its articular cavity. However, detailed information is meager. The present study examined the formation process of the articular cavity in the rat TMJ by immunocytochemistry for CD31, RECA-1, and ED1, which are useful cellular markers for endothelial cells and monocyte/macrophage lineages, respectively. The upper articular cavity formation had begun by embryonic day 21 (E21) and was completed at postnatal day 1 (P1) in advance of the lower cavitation; the latter took place from P1 to P3. The occurrence and distribution pattern of the CD31-, RECA-1-, and ED1-positive cells differed between the upper and lower articular cavity-forming areas: the ED1-positive cells exclusively occurred in the area of the prospective upper articular cavity prior to its formation, while no ED1-positive cell appeared in the lower cavity-forming area. In contrast, the CD31- and RECA-1-positive endothelial cells were restricted to the lower cavity-forming area (never the prospective upper cavity) at E19 and diminished thereafter. Throughout the cavity formation, we failed to find any apoptotic cells in the cavity formation area, indicating no involvement of apoptosis in the cavity formation in TMJ. The present findings on the behaviors of endothelial cells and ED1-positive cells show a possibility of different mechanism in the cavity formation between the upper and lower articular cavities in the rat TMJ. The appearance of ED1-reactive cells and temporal vascularization may play crucial roles in the upper and lower articular cavity formation, respectively. 相似文献