首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   924篇
  免费   64篇
  国内免费   33篇
耳鼻咽喉   6篇
儿科学   9篇
妇产科学   6篇
基础医学   160篇
口腔科学   20篇
临床医学   70篇
内科学   61篇
皮肤病学   3篇
神经病学   59篇
特种医学   33篇
外科学   48篇
综合类   184篇
预防医学   82篇
眼科学   9篇
药学   97篇
中国医学   148篇
肿瘤学   26篇
  2024年   4篇
  2023年   8篇
  2022年   21篇
  2021年   30篇
  2020年   23篇
  2019年   17篇
  2018年   18篇
  2017年   21篇
  2016年   23篇
  2015年   32篇
  2014年   57篇
  2013年   46篇
  2012年   77篇
  2011年   78篇
  2010年   64篇
  2009年   46篇
  2008年   50篇
  2007年   54篇
  2006年   44篇
  2005年   39篇
  2004年   41篇
  2003年   29篇
  2002年   18篇
  2001年   15篇
  2000年   10篇
  1999年   9篇
  1998年   11篇
  1997年   10篇
  1996年   9篇
  1995年   7篇
  1994年   6篇
  1993年   9篇
  1992年   8篇
  1991年   3篇
  1990年   6篇
  1989年   4篇
  1988年   6篇
  1986年   5篇
  1985年   2篇
  1984年   6篇
  1983年   10篇
  1982年   8篇
  1981年   12篇
  1980年   10篇
  1979年   3篇
  1978年   3篇
  1977年   4篇
  1976年   2篇
  1975年   1篇
  1974年   1篇
排序方式: 共有1021条查询结果,搜索用时 15 毫秒
1.
During lower extremity amputation, the objective is to provide a functional residual limb that permits maximum patient mobility and independence. Preservation of length of the fore part of the foot using salvageable tissue from the amputated part in young patients prevents equines deformity and revision of amputation to a higher level. This can be achieved using tissue available from the amputated part. The spare part concept in reconstructive surgery should be integrated into the trauma algorithm to avoid additional donor site morbidity. Reported here is a young adult patient with crush injuries to both feet, which resulted in amputations. A fasciocutaneous flap raised from one extremity was used to facilitate transmetatarsal amputation stump length preservation of the other extremity.  相似文献   
2.
急性中风中脏腑证型与垂体-肾上腺轴激素关系的研究   总被引:6,自引:0,他引:6  
目的 :探讨急性中风中脏腑证型与垂体—肾上腺轴激素的促肾上腺皮质激素 (ACTH)、皮质醇 (CS)的关系。方法 :对 78例中脏腑患者进行辨证分型 ,同时利用放射免疫分析 (RIA)法测定血中 ACTH、CS含量 ,按证型分为四组 ,对比不同证型间 ACTH、CS的水平 ,并与健康人组 (60例 )作对照。结果 :ACTH、CS含量水平比较 :1四种证型的 ACTH、CS均比正常健康人组高 (P <0 .0 0 1 ) ;2四种证型间比较有明显差异 (P<0 .0 1 ) ,从高到低为 :痰热内闭心窍证 >风火上扰清窍证 >痰湿蒙塞心神证 >元气败脱、心神散乱证。结论 :ACTH、CS含量水平可作为判别中脏腑不同证型间的微观指标  相似文献   
3.
对四种同季不同产地采集的“三颗针”不同部位的四种生物碱进行了含量测定和分析,为该类药材的质量研究、生药采收、药厂选投料及开发应用等提供了科学依据。同时对该类资源的可持续利用也具有积极意义。  相似文献   
4.
肩肱皮瓣修复颈部瘢痕挛缩畸形疗效分析   总被引:1,自引:0,他引:1  
目的:探讨颈部瘢痕挛缩畸形的有效外科治疗手段。方法:采用瘢痕广泛松解、双侧或单侧肩肱皮瓣转移,同时用全厚皮片移植修复供瓣区创面。结果:本组21例中,17例手术一次性完成,4例分两次完成。不但改善了患者的上肢功能,还可进一步改善患者颈部的活动度。结论:瘢痕广泛松解、双侧或单侧肩肱皮瓣转移,同时用全厚皮片移植修复供瓣区创面是颈部瘢痕挛缩畸形的有效外科治疗手段。  相似文献   
5.
Summary In urethane anesthetized rats neuronal responses of the visual part of nucleus reticularis thalami (vTR) to light were compared with those during pairing light as a conditioned stimulus (CS) with the electrical stimulation of the rat's tail (US). The intensity of the US was adjusted to the minimum required to evoke a slight freezing behavior in the awake rat. The firing rate of most vTR neurons decreased in the period between light and US application (P < 0.01). Significant response modulations to light were observed in 39% of the units, in most of them they persisted over an extinction period of 15 min. In addition, neurons which were predominantly inhibited by conditioning sometimes changed from regular spiking to a burst pattern. The results support the hypothesis that conditioning related facilitation of geniculate neurons observed in previous experiments can be explained at least partly by disinhibition of geniculate units from vTR.  相似文献   
6.
Male wild (Cavia aperea) and domestic (C. porcellus) guinea pigs were tested in two-bottle choice tests for preferences between glucose solutions of different concentrations and de-ionized water. Wild males showed significant preferences for concentrations between 0.025 and 0.4 M glucose while domestic males preferred only the 0.2 M glucose solution to de-ionized water. C. aperea males also consumed significantly greater volumes of liquid per kg body wt.34 during the glucose tests than did the C. porcellus males. These comparative results contrast sharply with those obtained by other authors with wild and domestic Norway rats.  相似文献   
7.
M Ikeda  T Tanami  M Matsushita 《Neuroscience》1984,12(4):1243-1260
The distribution of cells of origin of ascending and descending internuclear connections in the trigeminal sensory nuclei was studied by the retrograde horseradish peroxidase technique in the cat. The termination of collaterals of these ascending axons was also studied by the anterograde transport of horseradish peroxidase. Following injections of horseradish peroxidase into the ventral part of the principal sensory nucleus and the adjacent reticular formation many small neurons were labeled ipsilaterally in the whole area of the caudal portion of the nucleus interpolaris and in laminae III and IV of the nucleus caudalis. Labeled neurons were also found in laminae I and V. Injections limited to either nucleus oralis, the ventral part of the principal sensory nucleus and the medial parabrachial nucleus labeled similar types of neurons in the above regions with a topographic relationship; neurons in the dorsal part of the nuclei caudalis and interpolaris project, dorsally, to rostral portions of the trigeminal sensory nuclei while those in the ventral part of the nuclei caudalis and interpolaris project ventrally. Anterograde labeling of axons arising from the nucleus caudalis demonstrates that the axons ascend in the intranuclear bundles and the adjacent reticular formation, and give off collaterals to the nuclei interpolaris and oralis, and the ventral part of the principal sensory nucleus. Injections limited to the nucleus caudalis labeled small neurons in the rostral portion of the nucleus oralis and the caudal portion of the nucleus interpolaris. The present study suggests that these ascending and descending internuclear connections of the trigeminal sensory nuclei may modulate transmission of afferent inputs to various projection sites, such as thalamus, superior colliculus, cerebellum and spinal cord.  相似文献   
8.
A rare case of an alveolar soft part sarcoma of the uterine cervix in an 8 year old girl is presented. The patient was admitted because of genital bleeding lasting for 7 months. A polypoid tumor, 2times1.5 cm in diameter, was found in her external uterine os and was surgically resected. Microscopically, the tumor consisted of a uniform sheet of tumor cells in the cytoplasm which contained granules and which were stained with periodic acid-Schiff, both before and after the diastase digestion. Alveolar arrangement of the tumor cells was manifested with reticulin silver impregnation. Dense, membrane bound granules were evident at an ultrastructural level in the cytoplasm of the tumor cells. An immunohistochemical examination demonstrated a positive reaction for anti-desmin, anti-myoglobin, anti-HHF35 and anti-neuron specific enolase in the cytoplasm.  相似文献   
9.
The role of several motor and intralaminar thalamic nuclei in the regulation of dopamine release from terminals and dendrites of the nigrostriatal dopaminergic neurons was investigated in halothane-anaesthetized cats. For this purpose, the effects of the unilateral electrical stimulation of various thalamic nuclei on the release of newly synthesized [3H]dopamine were simultaneously determined in both substantiae nigrae and caudate nuclei using the push-pull cannula method. The electrical stimulation of the motor nuclei was the only one to induce asymmetric changes in the four structures since [3H]dopamine release was enhanced in the ipsilateral caudate nucleus and reduced in the contralateral structure while opposite responses were observed in the corresponding substantiae nigrae. A reduction of [3H]dopamine release occurred in the four structures or only in the contralateral substantia nigra and caudate nucleus following the stimulation of the parafascicularis nucleus and the adjacent posterior part of the nucleus centrum medianum or of the nucleus centralis lateralis and the adjacent paralaminar part of the nucleus medialis dorsalis, respectively. The stimulation of the anterior part of the nucleus centrum medianum, which in contrast to other thalamic nuclei examined, receives few nigral inputs, selectively enhanced [3H]dopamine release in the contralateral substantia nigra. No significant changes in [3H]dopamine release were seen either in the substantiae nigrae or in the caudate nuclei following the stimulation of midline thalamic nuclei. These results indicate that the motor and intralaminar thalamic nuclei exert multiple and selective influences on the release of dopamine from terminals and/or dendrites of the dopaminergic neurons. They also further support a role of thalamic nuclei in the transfer of information from one substantia nigra to the contralateral dopaminergic neurons. The possible involvement of connections between paired thalamic nuclei was underlined by the observations of evoked potentials in contralateral homologous nuclei following unilateral stimulation of motor, or some intralaminar, nuclei. The present report provides new insights on the mechanisms contributing to the reciprocal and/or bilateral regulations of nigrostriatal dopaminergic pathways.  相似文献   
10.
输精管精索部的应用解剖   总被引:1,自引:0,他引:1  
目的:为输精管结扎术、吻合术的临床应用提供形态学基础。方法:选用30具成人男性尸体对输精管精索部进行了解剖学观测。结果:输精管精索部位于精索后方,睾丸动脉位于中央,静脉位于最前方,生殖股神经生殖支位于输精管精索部外侧。输精管精索部长左侧7.6±2.9(50~11.3)cm;右侧7.3±3.2(5.2~11.0)cm。其内径左、右侧均为0.6±0.1(0.4~0.8)mm。经统计学处理(P>0.05)左右侧均无显著性差异。结论:在输精管结扎术、吻合术手术时应注意保护输精管外侧的生殖股神经生殖支、输精管精索部管径小、壁厚、吻合成功率高。因管径小、术后不宜安放支架,以免术后引起管腔阻塞。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号