全文获取类型
收费全文 | 435536篇 |
免费 | 29437篇 |
国内免费 | 6886篇 |
专业分类
耳鼻咽喉 | 5811篇 |
儿科学 | 8782篇 |
妇产科学 | 10602篇 |
基础医学 | 58824篇 |
口腔科学 | 12616篇 |
临床医学 | 37375篇 |
内科学 | 85749篇 |
皮肤病学 | 9066篇 |
神经病学 | 29860篇 |
特种医学 | 16126篇 |
外国民族医学 | 118篇 |
外科学 | 66737篇 |
综合类 | 20565篇 |
现状与发展 | 14篇 |
一般理论 | 67篇 |
预防医学 | 21473篇 |
眼科学 | 11014篇 |
药学 | 37141篇 |
54篇 | |
中国医学 | 6301篇 |
肿瘤学 | 33564篇 |
出版年
2022年 | 3481篇 |
2021年 | 5518篇 |
2020年 | 4006篇 |
2019年 | 4561篇 |
2018年 | 6475篇 |
2017年 | 5378篇 |
2016年 | 5274篇 |
2015年 | 6848篇 |
2014年 | 9247篇 |
2013年 | 10640篇 |
2012年 | 14752篇 |
2011年 | 15282篇 |
2010年 | 9733篇 |
2009年 | 8690篇 |
2008年 | 12736篇 |
2007年 | 13308篇 |
2006年 | 13163篇 |
2005年 | 12010篇 |
2004年 | 10545篇 |
2003年 | 10190篇 |
2002年 | 9565篇 |
2001年 | 29257篇 |
2000年 | 29739篇 |
1999年 | 24582篇 |
1998年 | 5756篇 |
1997年 | 4794篇 |
1996年 | 4290篇 |
1995年 | 3916篇 |
1994年 | 3437篇 |
1993年 | 3093篇 |
1992年 | 16321篇 |
1991年 | 15069篇 |
1990年 | 14335篇 |
1989年 | 14088篇 |
1988年 | 12724篇 |
1987年 | 12183篇 |
1986年 | 11182篇 |
1985年 | 10381篇 |
1984年 | 6957篇 |
1983年 | 5621篇 |
1982年 | 2739篇 |
1979年 | 5501篇 |
1978年 | 3359篇 |
1977年 | 2980篇 |
1975年 | 2652篇 |
1974年 | 3068篇 |
1973年 | 2876篇 |
1972年 | 2835篇 |
1971年 | 2776篇 |
1969年 | 2544篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
This study focuses on obtaining more information about the site of anastomosis, with three-dimensional examination using methylmethacrylate resin (Mercox) corrosion casts. Seventy microvascular anastomoses were performed in Wistar albino rats, divided into two groups before sacrifice. In Group 1 (35), Mercox was injected into the vessels, whereas in Group 2 (35), the tissues were prepared without injecting Mercox. Both groups were compared under the scanning electron microscope (SEM). The SEM preparation in Group 1 was simple, easy, and artifacts were significantly minimized. The anastomotic site could be well appreciated in three-dimensional views. Clear negative imprints of the endothelial surface were achieved without any breakage in the Mercox corrosion cast, and it can be reliably used in the evaluation of small vessel anastomosis. 相似文献
92.
93.
We experienced one necropsy case of brainstem encephalitis of Iizuka type (BSE) and one necropsy case of the brain-stem syndrome (BSS) of typical neuro-Beh?et's disease, and compared them clinically and neuropathologically. Clinically both of these cases showed chronic progressive mental disturbance, pseudobulbar paresis, spastic tetraparesis, cerebrospinal fluid pleocytosis, increased protein, and brainstem atrophy observed by X-CT. Neuropathologically, irregular, boundary-indistinct demyelinating lesions and obsolete softening lesions were sporadically found, associated with perivascular lymphocytic infiltration and gliosis centering on the brainstem. In this way, both cases were similar in many points except for the presence or absence of cutaneo-muco-ocular signs specific for Beh?et's disease. Also BSE and BSS reports in the literature showed that both diseases were similar not only in clinical findings consisting of mental disturbance and brainstem signs but also in neuropathological findings with similar topographical distribution of the same histopathological changes, including the variations and diversity of these characteristics. Especially of much interest is their similarity in characteristic mental disturbance. In discriminating BSE from multiple sclerosis and other diseases with exclusive involvement of the brainstem, it is important to understand their clinical characteristics. The characteristic mental disturbance includes damage to memory and sentiment, a change in personality, and lowering in spontaneity, but calculation ability and orientation are comparatively preserved. Of course the similarity in clinical and neuropathological findings does not necessarily mean the identical etiopathogenesis. However, it is possible to consider that neuro-Beh?et's disease (syndrome) may form a wide spectrum with BSE and typical neuro-Beh?et's disease at the both ends, regarding the time and spatial diversity of the appearance of cutaneo-muco-ocular signs. 相似文献
94.
95.
For monitoring the changes in intracellular free Ca2+ concentration ([Ca2+]i), we developed a simple system combining a fluorescence microscope, an image intensifier, a video-camera, a cathode ray tube display and a photodiode, employing quin2 as a Ca2+ indicator. We recorded increases of the fluorescence intensity due to [Ca2+]i rises, when high K+ medium, neurotransmitter and Ca2+ ionophore were applied to the single cells of nervous system origin in culture. The present system is capable of simultaneous detection of the [Ca2+]i changes from multiple separate cells. 相似文献
96.
Phenytoin-induced gingival overgrowth is a recognized side effect in many cerebral palsy patients using diphenyl hydantoin for the control of seizures. Severe gingival overgrowth in these patients can affect normal masticatory function, lead to poor occlusal development, and compromise esthetics. This report addresses the complex nature of treating phenytoin-induced gingival overgrowth in a mentally retarded 20-year-old female patient. For this patient, full-mouth gingivectomy procedure was performed under general anesthesia in a single session. Post operative follow-up was uneventful. This article discusses major indications, contraindications, and protocols to be followed for periodontal surgical procedures done under general anesthesia. 相似文献
97.
98.
In this new radioimmunoassay system for determination of amatoxins in urine and plasma, a novel chemical approach is used for antigen and 125I-tracer production, based on a detoxified alpha-amanitin derivative (aldoamanitin). Total assay time, including data processing, is less than 100 min. The lowest detectable concentration is 1 microgram/L for urine, 0.1 microgram/L for plasma. In the clinically significant range, within-run CVs are less than 8%. This new 125I-based assay is a significant improvement over existing 3H technology in terms of speed, precision, and freedom from interference. 相似文献
99.
100.
S Mizuno H Funahashi H Sugiura T Imai M Takeuchi Y Sato H Takagi 《Nihon Geka Gakkai zasshi》1986,87(8):883-888
Bilateral cervical lymph node dissection was performed in 71 cases of papillary thyroid carcinoma, considered to be relatively early cases because of mobility, irrespective of the size of tumor or presence of node enlargement. Of these, 33 cases received additional node dissection of the anterosuperior mediastinum through longitudinal sternotomy. The number of lymph nodes examined per subject averaged 89.9, the number of metastatic nodes was 13.8, and metastasis was noted in 88.7% of all cases. Lymph node metastasis tended to be more frequent on the affected side, but was simultaneously scattered over the whole cervical area. As to sites, metastasis of paratracheal nodes on the affected side occurred at a frequency of 66.2%, inferior and superior jugular nodes at 62.0% and 59.0% respectively, pretracheal nodes at 50.7%, and tracheoesophageal nodes at 47.9%. The high incidence of para- and pretracheal nodes suggests that the lymph flow in this direction is of great importance in metastasis. In fact, lymph nodes in the mediastinum, which were directly continuous with these nodes, showed as high as 39.4% metastasis in cases of anterosuperior mediastinal extirpation. This extensive node dissection is considered to be very preferable as at least the agony of survival with carcinoma can be lessened. 相似文献