全文获取类型
收费全文 | 166254篇 |
免费 | 6387篇 |
国内免费 | 390篇 |
专业分类
耳鼻咽喉 | 2224篇 |
儿科学 | 4816篇 |
妇产科学 | 3879篇 |
基础医学 | 23780篇 |
口腔科学 | 5448篇 |
临床医学 | 9489篇 |
内科学 | 36774篇 |
皮肤病学 | 4685篇 |
神经病学 | 13314篇 |
特种医学 | 4218篇 |
外国民族医学 | 1篇 |
外科学 | 19166篇 |
综合类 | 800篇 |
一般理论 | 24篇 |
预防医学 | 19870篇 |
眼科学 | 4325篇 |
药学 | 12903篇 |
中国医学 | 678篇 |
肿瘤学 | 6637篇 |
出版年
2023年 | 825篇 |
2022年 | 658篇 |
2021年 | 2600篇 |
2020年 | 1467篇 |
2019年 | 2972篇 |
2018年 | 4959篇 |
2017年 | 3090篇 |
2016年 | 3087篇 |
2015年 | 3434篇 |
2014年 | 3879篇 |
2013年 | 5908篇 |
2012年 | 10101篇 |
2011年 | 10654篇 |
2010年 | 5323篇 |
2009年 | 3954篇 |
2008年 | 8716篇 |
2007年 | 9374篇 |
2006年 | 8991篇 |
2005年 | 8610篇 |
2004年 | 7963篇 |
2003年 | 7455篇 |
2002年 | 7103篇 |
2001年 | 4914篇 |
2000年 | 5480篇 |
1999年 | 4187篇 |
1998年 | 827篇 |
1992年 | 2241篇 |
1991年 | 2019篇 |
1990年 | 1999篇 |
1989年 | 1728篇 |
1988年 | 1652篇 |
1987年 | 1537篇 |
1986年 | 1570篇 |
1985年 | 1476篇 |
1984年 | 1060篇 |
1983年 | 905篇 |
1979年 | 1224篇 |
1978年 | 820篇 |
1977年 | 795篇 |
1976年 | 758篇 |
1975年 | 887篇 |
1974年 | 1126篇 |
1973年 | 1178篇 |
1972年 | 1120篇 |
1971年 | 1083篇 |
1970年 | 1012篇 |
1969年 | 1088篇 |
1968年 | 1110篇 |
1967年 | 981篇 |
1966年 | 883篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
Leire Ambrosio PhD Mª Victoria Navarta-Sánchez PhD Mª Carmen Portillo PhD Raquel Martin-Lanas PhD Miriam Recio MSc Mario Riverol PhD 《Health & social care in the community》2021,29(4):1030-1040
Psychosocial adjustment to a complex and disabling long-term condition like Parkinson´s disease is a complex, dynamic, cyclical and interactive process. Family caregivers, face multiple challenges that require a significant effort in terms of psychosocial adjustment, which must be considered by healthcare professionals in order to provide a holistic care. The patients’ self-report version of the Psychosocial Adjustment to Illness Scale (PAIS-SR), which has been validated in Spain for use in Parkinson's disease, is designed to evaluate the psychosocial adjustment of patients. Our purpose was to validate the Spanish PAIS-SR version for caregivers of patients with Parkinson's disease. An open, national cross-sectional study with one point-in-time evaluation and retest was carried out in 450 family caregivers of patients with Parkinson's disease. Data were collected in Spain from April 2016 to September 2017. The psychometric analysis performed showed that the Spanish version of the PAIS-SR for caregivers presents adequate indicators of reliability, internal and external validity, and is structured according to the seven-domain model proposed by the author of the instrument. 相似文献
952.
953.
Salcedo M Taja L Utrera D Chávez P Hidalgo A Pérez C Benítez L Castañeda C Delgado R Gariglio P 《International journal of experimental pathology》2002,83(6):275-286
The role of tumour suppressor genes in the development of human cancers has been studied extensively. In viral carcinogenesis, the inactivation of suppressor proteins such as retinoblastoma (pRb) and p53, and cellular oncogenes overexpression, such as c-myc, has been the subject of a number of investigations. In uterine-cervix carcinomas, where high-risk human papillomavirus (HPV) plays an important role, pRb and p53 are inactivated by E7 and E6 viral oncoproteins, respectively. However, little is known about the in situ expression of some of these proteins in pre-malignant and malignant cervical tissues. On the other hand, it has also been demonstrated that c-myc is involved in cervical carcinogenesis, and that pRb participates in the control of c-myc gene expression. By using immunostaining techniques, we investigated pRb immunodetection pattern in normal tissues, squamous intraepithelial lesions (SILs) and invasive carcinomas from the uterine cervix. Our data show low pRb detection in both normal cervical tissue and invasive lesions, but a higher expression in SILs. C-Myc protein was observed in most of the cellular nuclei of the invasive lesions, while in SILs was low. These findings indicate a heterogeneous pRb immunostaining during the different stages of cervical carcinogenesis, and suggest that this staining pattern could be a common feature implicated in the pathogenesis of uterine-cervix carcinoma. 相似文献
954.
955.
956.
A. Bass J. Teisinger P. Hnik E. V. Macková R. Vejsada I. Eržen 《Pflügers Archiv : European journal of physiology》1984,400(2):188-193
Muscle hypertrophy was induced in the soleus muscle of young rats by tenotomy of the gastrocnemius and plantaris muscles. Three and 7 days afterwards the sciatic nerve was sectioned. The loss of weight of muscles subjected to this combined procedure three days after denervation was 30–40%. Lysosomal enzyme activities (acid phosphatase, -glucosidase, -galactosidase and N-acetyl--d-glucosaminidase) and energy enzyme activities (lactate dehydrogenase, LDH, triose-3-phosphate dehydrogenase, TPDH,d-hexokinase, HK and citrate synthase, CS) were determined 3 days after denervation, 3, 7 and 10 days after hypertrophy had been induced and 3 days after denervation of hypertrophying muscles on day 3 and 7. Normal non-operated rats of corresponding body wieght served as controls and their enzyme activities were estimated on the same day. In the course of muscle hypertrophy, the 4 lysosomal enzyme activities increased progressively. Although 3 days' denervation of control muscles did not alter lysomal enzyme activities, denervation of hypertrophying muscles greatly enhanced the activity of these enzymes. Enzymes of energy metabolism were affected to a lesser degree. The results suggest that denervation of hypertrophying muscles causes more extreme changes in muscle weight and lysosomal enzyme activities than denervation alone. The possible implications of this finding are discussed in relation to the rapid atrophy. 相似文献
957.
The ontogeny of lymphocytes expressing J chain in the cytoplasm (J+) was studied in pig foetuses by the immunofluorescent technique. Peripheral blood lymphocytes were the first J+ cells in prenatal life. The spleen and lymph nodes contained J+ cells in the last days of gestation. J+ cells were found in the lamina propria of the gut and some glands of conventional but not of germ-free piglets. J chain was not detected on or in cell membranes at any developmental stage. 相似文献
958.
Elizabeth Knyihár-Csillik Ágotha Török Bert Csillik 《The Journal of comparative neurology》1990,297(4):594-612
Substance P-like immunoreactivity (SPLI) was localized in the superficial spinal dorsal horn of the rat by means of light and electron microscopic immunocytochemical techniques. Serial immunocytochemical sections were subjected to densitometric measurements with an electronic Image Analyser, and with aid of a computer program, a two-dimensional reconstruction of the fine neuroanatomical structure of the SPLI-active regions of the lumbosacral upper superficial spinal dorsal horn was obtained. SPLI activity in the superficial dorsal horn outlines four well-marked and distinctly differing regions, called, in the mediolateral sequence, areas A, B, C, and D, plus Cajal's noyeau interstitiel ("lateral spinal nucleus" = "nucleus of the dorsolateral fascicle," L). Lumbosacral dorsal rhizotomy results in an almost complete depletion of SPLI from ipsilateral areas A, B, C, and D; it induces decreased SPLI in the area of the lateral spinal nucleus (L), ipsi- or contralaterally in an alternating fashion. Transection of the segmentally related, ipsilateral peripheral nerve induces a marked depletion of SPLI from areas A, B, and C but only a slight decrease in area D and virtually none in the area of L. Whereas a simple crush of the peripheral nerve (axocompression) induces only a slight depletion of SPLI, if any, semiautomatic densitometric analysis of serial immunocytochemical sections proves that a controlled crush injury (axocontusion) results in depletion of SPLI from the upper dorsal horn, similar to transection of the peripheral nerve. Following regeneration of the ipsilateral, segmentally related peripheral nerve, the original immunocytochemical structure of the superficial dorsal horn is re-established by SPLI-positive axonal sprouts originating from previously damaged dorsal root axons. 相似文献
959.
E Sántha G Répásy M Varga 《Magyar traumatológia, orthopaedia és helyreállító sebészet》1990,33(4):291-295
A thought, returning again and again in hand surgery, is the immediate introduction of active motion therapy after the reconstructive operations of the flexor tendons. To the active motion an adequately strong tendon suture, to the definition of "adequately strong tendon suture" however the measurement of the pulling force, acting actually on the flexor tendons is necessary. Authors attempted to measure this pulling force during flexor tendon operations on cadaver's hand. On the basis of their measurements the maximal pulling force, that can be expected during postoperative active movement exercises with adequate circumspection, can be estimated as two kiloponds. 相似文献
960.
Computer simulations were carried out in an attempt to understand the possible operating modes of synaptic triadic arrangements as described in the dorsal lateral geniculate nucleus of the monkey. Small networks of "chaotic" units (piecewise linear internal maps) were used to investigate their performance as ON-gates for the transmission of spikes. "Chaotic" units have advantages over "logic" units because the former are asynchronous, it is possible to simulate temporal summation, and also to adjust subthreshold time-constants. It was demonstrated that ensembles with single delay lines, representing "closely-packed" triads, were hardly capable of realizing reliable and efficient ON-gate operations. Networks with multiple delayed lines, patterned after triads "at a distance" coupled with "closely-packed" triads, were capable of secure ON-gate functions. Such gates were input dependent, becoming reliable only when high frequency bursts were used as the source of activity. Moreover, the ON-gate could be temporarily interrupted by square wave bursts applied to the inhibitory units, a situation resembling electron microscopic observations of interneuron to interneuron synapses in the LGNd. 相似文献