全文获取类型
收费全文 | 35742篇 |
免费 | 2405篇 |
国内免费 | 2124篇 |
专业分类
耳鼻咽喉 | 1514篇 |
儿科学 | 265篇 |
妇产科学 | 107篇 |
基础医学 | 4994篇 |
口腔科学 | 919篇 |
临床医学 | 2820篇 |
内科学 | 1460篇 |
皮肤病学 | 183篇 |
神经病学 | 9092篇 |
特种医学 | 1020篇 |
外国民族医学 | 2篇 |
外科学 | 6120篇 |
综合类 | 4409篇 |
预防医学 | 447篇 |
眼科学 | 3848篇 |
药学 | 1626篇 |
16篇 | |
中国医学 | 943篇 |
肿瘤学 | 486篇 |
出版年
2024年 | 83篇 |
2023年 | 468篇 |
2022年 | 858篇 |
2021年 | 1168篇 |
2020年 | 1214篇 |
2019年 | 1052篇 |
2018年 | 1042篇 |
2017年 | 1303篇 |
2016年 | 1313篇 |
2015年 | 1284篇 |
2014年 | 2078篇 |
2013年 | 2218篇 |
2012年 | 1629篇 |
2011年 | 1809篇 |
2010年 | 1676篇 |
2009年 | 1493篇 |
2008年 | 1713篇 |
2007年 | 1697篇 |
2006年 | 1558篇 |
2005年 | 1337篇 |
2004年 | 1230篇 |
2003年 | 1158篇 |
2002年 | 1043篇 |
2001年 | 916篇 |
2000年 | 745篇 |
1999年 | 710篇 |
1998年 | 725篇 |
1997年 | 643篇 |
1996年 | 531篇 |
1995年 | 492篇 |
1994年 | 432篇 |
1993年 | 391篇 |
1992年 | 411篇 |
1991年 | 368篇 |
1990年 | 356篇 |
1989年 | 297篇 |
1988年 | 270篇 |
1987年 | 271篇 |
1986年 | 264篇 |
1985年 | 368篇 |
1984年 | 311篇 |
1983年 | 221篇 |
1982年 | 254篇 |
1981年 | 223篇 |
1980年 | 202篇 |
1979年 | 127篇 |
1978年 | 79篇 |
1977年 | 75篇 |
1976年 | 59篇 |
1975年 | 31篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
[目的]探讨腓浅神经浅支修复桡神经缺损的临床效果。[方法]对腓浅神经浅支与桡神经形态结构进行比较,并对腓浅神经浅支移植修复桡神经缺损性损伤5例进行临床分析。[结果]腓浅神经浅支与桡神经形态结构大体一致.5例病例平均随访11(8~26)个月.按文献标准评定,优3例,良2例。[结论]腓浅神经浅支可作为修复桡神经缺损理想的供体神经。 相似文献
22.
The purpose of this study was to determine if changes in hindlimb motoneuron membrane electrical properties occur 4–6 months after spinal transection in the adult animal. Eight acute and nine chronic animals were spinalized at T12. Intracellular recordings from motoneurons innervating the triceps surae were performed. Membrane electrical properties, including resting potential, action potential peak amplitude, afterhyperpolarization duration, rheobasic current, input resistance and axonal conduction velocity were measured. There were no statistical differences found between group means or frequency distributions in the membrane properties of motoneurons assessed from acute and chronic spinal animals. Thus, alteration of motoneuron membrane properties does not appear to be a major contributing factor to the hyperexcitable hindlimb reflex activity demonstrated by chronic spinal animals. 相似文献
23.
Daniela Klitscher Lars P. Müller Pol Rommens 《European journal of trauma and emergency surgery》2007,33(1):69-73
Abstract 10 embalmed cadaver forearms and wrists were dissected to determine the anatomical course of the superficial branch of the
radial nerve in the distal forearm. The superficial radial nerve bifurcated in two branches at a mean of 54,7 mm proximal
to the radial styloid. From the styloid process of the radius, the mean distance to the closest dorsal branch of the superficial
radial nerve was 3,5 mm and the mean distance to the closest volar branch was 9,8 mm. The mean distance between the closest
branch of the superficial radial nerve and Lister?s tubercle was 16,4 mm. The crossing point between the nerve and the cephalic
vein was located at a mean of 54,3 mm proximal to the styloid process. At the level of styloid process the mean distance between
the closest dorsal branch of the superficial radial nerve and the first dorsal compartment was 15,2 mm and between the closest
volar branch and the first dorsal compartment 4,4 mm. Detailed knowledge of anatomic characteristics of the superficial branch
of the radial nerve may help prevent injury during operations and treat traumatic lesions of the nerve. Because of great variations
in the course of the superficial radial nerve we could not define an absolute safe zone for surgical procedures on the distal
forearm. Iatrogenic lesions of the superficial radial nerve are described complications of percutaneous procedures. Therefore
open surgical approaches are recommended.
Daniela Klitscher and Lars Peter Müller contributed equally to this work. 相似文献
24.
Changing glial organization relates to changing fiber order in the developing optic nerve of ferrets
The structures of the developing eye-stalk and the relationships of early retinofugal fibers as they pass through the stalk, chiasm, and tract have been studied by light and electron microscopical methods in fetal ferrets aged 23–27 days. The early eye-stalk can be divided into two parts: a narrow extracranial part has a narrow lumen and is lined by few cells, whereas a thicker intracranial part has a wider lumen and is lined by several rows of cells. At the earliest stages no axon bundles are recognizable in the stalk, but fibers of the supraoptic commissure are already beginning to cross the midline in the diencephalon. Subsequently, as retinofugal axons invade the stalk, the glia of the extracranial part of the stalk have an interfascicular distribution and axon bundles are separately encircled by glial cytoplasm. In the intracranial part, as in the chiasm and tract, the glial cells occupy a periventricular position and send slender radial cytoplasmic processes to the subpial surface; these pass between groups of axons that here lie immediately deep to the subpial glia. Whereas axonal growth cones have no evident preferred distribution in the extracranial stalk, they tend to accumulate near the pial surface intracranially. The boundary between the two types of organization shifts as development proceeds so that the interfascicular glial structure of the early extracranial stalk first encroaches upon the intracranial parts and later appears in the chiasm. The characteristic adult arrangement of fibers in an age-related order in the optic chiasm and tract, but not in the optic nerve, can be understood if axonal growth cones are guided toward the pial surface by radial glia but not by interfascicular glia. From the distribution of the growth cones, this is what appears to happen. 相似文献
25.
Seiichi Saito Shunichi Namiki Kenji Numahata Makoto Satoh Shigeto Ishidoya Akihiro Ito Haruo Nakagawa Yasuhiro Kaiho Takehiko Sanada Atsushi Yamada Yoichi Arai 《International journal of urology》2007,14(2):133-139
PURPOSE: To determine the effect of an interposition nerve graft on sexual function after radical prostatectomy. METHODS: This study includes 64 patients, without hormonal therapy, who underwent a radical prostatectomy and intraoperative electrophysiological confirmation of cavernous nerve preservation. Twelve patients underwent a unilateral interposition sural nerve graft (UNG) for the resected neurovascular bundle. Twenty-one and 31 patients underwent bilateral nerve-sparing (BNS) and unilateral nerve-sparing (UNS) surgery without a nerve graft, respectively. As the age of patients was significantly younger in the UNG group than in the other groups, age-matched analysis also was conducted. Sexual function, evaluated by a self-administered questionnaire using the University of California Los Angeles-Prostate Cancer Index, was compared statistically among the three groups. RESULTS: In the age-matched analysis, the postoperative sexual function (SXF) score of the UNG group showed an intermediate level of recovery between those of the BNS and UNS groups at 12 months and reached the same level as the score at 12 months of the BNS group at 18 months postoperatively. The difference in the SXF score between the UNG and UNS groups began to appear after 6 months postoperatively and increased steadily with time. However, the background factors, such as the baseline SXF score, the usage rate of phosphodiesterase 5 inhibitors, and the rate of comorbidities were different between the UNG and UNS groups. CONCLUSIONS: The difference of the SXF score between the UNG and UNS groups increased with time after 6 months postoperatively. However, it might be difficult at present to attribute a better recovery of the SXF score to the nerve graft because of the difference in the background factors between the groups. 相似文献
26.
金桂红 《安徽卫生职业技术学院学报》2005,4(6):35-36
目的:探讨小儿腮腺炎并发中枢神经系统感染的临床特点.方法:对52例小儿腮腺炎并发中枢神经系统感染的临床资料进行回顾性总结分析.结果:3~7月份为小儿腮腺炎并发中枢神经系统感染的发病高峰季节(92.31%).发病年龄以6~12岁为主(82.69%),多发生于腮腺肿痛3天以上伴有持续发热者(78.85%),少数患者同时有其它脏器的损害,一般治疗疗效较好.结论:腮腺炎极易并发中枢神经系统感染,年长儿发生率高,应推广接种流腮活疫苗降低发病率. 相似文献
27.
28.
蒋丽君 《中国中医药信息杂志》2005,12(9):17-18
目的观察按压骨穴对围绝经期妇女心脏植物神经功能的影响。方法设按压骨穴组30例、空白对照组30例。用美国BraemarDL700型动态心电检测仪,检测试验前后的心率变异性(HRV):TF代表总频,LF代表交感神经活性,HF代表迷走神经活性,LF/HF代表交感神经与迷走神经均衡性。结果按压骨穴后4项指标均有显著下降(P<0.01,P<0.05)。空白对照组变化不显著(P>0.05)。骨穴组4项指标的变化率与对照组比较均有显著性差异(P<0.01)。结论按压骨穴有抑制心脏交感神经活性的良性调整作用,此效应具有相对的特异性。 相似文献
29.
30.
Elemental composition and water content of myelinated axons and glial cells in rat central nervous system 总被引:1,自引:0,他引:1
The distribution of elements (e.g. Na, Cl, K) and water in CNS cells is unknown. Therefore, electron probe X-ray microanalysis (EPMA) was used to measure water content and concentrations (mmol/kg dry or wet weight) of Na, Mg, P, S, Cl, K and Ca in morphological compartments of myelinated axons and glial cells from rat optic nerve and cervical spinal cord white matter. Axons in both CNS regions exhibited similar water content ( 90%), and relatively high concentrations (wet and dry weight) of K with low Na and Ca levels. The K content of axons was related to diameter, i.e. small axons in spinal cord and optic nerve had significantly less (25–50%) K than larger diameter axons from the same CNS region. The elemental composition of spinal cord mitochondria was similar to corresponding axoplasm, whereas the water content (75%) of these organelles was substantially lower than that of axoplasm. In glial cell cytoplasm of both CNS areas, P and K (wet and dry weight) were the most abundant elements and water content was approximately 75%. CNS myelin had predominantly high P levels and the lowest water content (33–55%) of any compartment measured. The results of this study demonstrate that each morphological compartment of CNS axons and glia exhibits a characteristic elemental composition and water content which might be related to the structure and function of that neuronal region. 相似文献