全文获取类型
收费全文 | 2181篇 |
免费 | 171篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 21篇 |
妇产科学 | 10篇 |
基础医学 | 214篇 |
口腔科学 | 35篇 |
临床医学 | 206篇 |
内科学 | 151篇 |
皮肤病学 | 8篇 |
神经病学 | 109篇 |
特种医学 | 171篇 |
外科学 | 101篇 |
综合类 | 376篇 |
一般理论 | 1篇 |
预防医学 | 275篇 |
眼科学 | 13篇 |
药学 | 232篇 |
中国医学 | 415篇 |
肿瘤学 | 47篇 |
出版年
2024年 | 12篇 |
2023年 | 28篇 |
2022年 | 60篇 |
2021年 | 95篇 |
2020年 | 78篇 |
2019年 | 61篇 |
2018年 | 63篇 |
2017年 | 47篇 |
2016年 | 64篇 |
2015年 | 74篇 |
2014年 | 150篇 |
2013年 | 110篇 |
2012年 | 152篇 |
2011年 | 206篇 |
2010年 | 169篇 |
2009年 | 111篇 |
2008年 | 124篇 |
2007年 | 116篇 |
2006年 | 98篇 |
2005年 | 87篇 |
2004年 | 77篇 |
2003年 | 59篇 |
2002年 | 37篇 |
2001年 | 27篇 |
2000年 | 25篇 |
1999年 | 24篇 |
1998年 | 19篇 |
1997年 | 20篇 |
1996年 | 16篇 |
1995年 | 20篇 |
1994年 | 12篇 |
1993年 | 15篇 |
1992年 | 13篇 |
1991年 | 4篇 |
1990年 | 12篇 |
1989年 | 13篇 |
1988年 | 9篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 6篇 |
1984年 | 10篇 |
1983年 | 10篇 |
1982年 | 10篇 |
1981年 | 13篇 |
1980年 | 10篇 |
1979年 | 3篇 |
1978年 | 5篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1969年 | 1篇 |
排序方式: 共有2400条查询结果,搜索用时 15 毫秒
1.
Chenicheri Balakrishnan Gil Altman Abdullah J Khalil 《CANADIAN JOURNAL OF PLASTIC SURGERY》2005,13(4):209-211
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.
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
3.
4.
5.
6.
目的 :考察 1 %盐酸丁卡因滴眼液的稳定性 ,确定其有效贮存期。方法 :采用经典恒温法预测其有效期。结果 :经典恒温法[1 ] 预测室温贮存期约为 2 0d ,冰箱贮存期约为 1 1 0d。结论 :该制剂对热不稳定 ,应冷藏。 相似文献
7.
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 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
8.
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
9.
Yosuke Morimitsu Hiroshi Tanaka Shigeaki Iwanaga Masamichi Kojiro 《Pathology international》1993,43(4):204-208
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
10.
We present a theoretical model of gas transport through the dead space during high-frequency ventilation (HFV) with volumes
less than dead space volume. The analysis is based on the axial distribution of transit times of gas moving through the dead
space. The model predicts that for tidal volumes (V) much less than dead space (Vd), gas exchange will be proportional to the product of frequency (f) and V2. If gas transport is analyzed in terms of Fick's law, then the effective diffusion coefficient (Deff) can be shown to be equal to fV2 times a constant, whose value equals the square of the coefficient of dispersion of axial transit times through the dead
space
. Experimental results in straight tubes fit the predictions of this model quite well. A
through the entire dead space of about 30% is more than sufficient to account for gas exchange during HFV in physical models
or in intact animals. An axial dispersion of this magnitude can be measured directly from a typical Fowler dead space determination
in healthy subjects. 相似文献