全文获取类型
收费全文 | 214950篇 |
免费 | 9819篇 |
国内免费 | 628篇 |
专业分类
耳鼻咽喉 | 3268篇 |
儿科学 | 5922篇 |
妇产科学 | 4861篇 |
基础医学 | 29361篇 |
口腔科学 | 7694篇 |
临床医学 | 14572篇 |
内科学 | 51643篇 |
皮肤病学 | 6323篇 |
神经病学 | 17947篇 |
特种医学 | 5148篇 |
外国民族医学 | 2篇 |
外科学 | 26437篇 |
综合类 | 1253篇 |
一般理论 | 70篇 |
预防医学 | 20430篇 |
眼科学 | 4468篇 |
药学 | 15205篇 |
中国医学 | 1074篇 |
肿瘤学 | 9719篇 |
出版年
2023年 | 1314篇 |
2022年 | 1877篇 |
2021年 | 4865篇 |
2020年 | 2591篇 |
2019年 | 4723篇 |
2018年 | 7112篇 |
2017年 | 4336篇 |
2016年 | 4342篇 |
2015年 | 5197篇 |
2014年 | 6430篇 |
2013年 | 9274篇 |
2012年 | 15833篇 |
2011年 | 16851篇 |
2010年 | 8432篇 |
2009年 | 6473篇 |
2008年 | 13408篇 |
2007年 | 14089篇 |
2006年 | 13436篇 |
2005年 | 13183篇 |
2004年 | 11963篇 |
2003年 | 11080篇 |
2002年 | 10332篇 |
2001年 | 5918篇 |
2000年 | 6944篇 |
1999年 | 4899篇 |
1998年 | 1084篇 |
1997年 | 821篇 |
1996年 | 711篇 |
1995年 | 640篇 |
1994年 | 517篇 |
1993年 | 438篇 |
1992年 | 1665篇 |
1991年 | 1391篇 |
1990年 | 1221篇 |
1989年 | 1042篇 |
1988年 | 896篇 |
1987年 | 814篇 |
1986年 | 833篇 |
1985年 | 736篇 |
1984年 | 574篇 |
1983年 | 469篇 |
1982年 | 339篇 |
1979年 | 493篇 |
1978年 | 348篇 |
1974年 | 433篇 |
1973年 | 421篇 |
1972年 | 345篇 |
1971年 | 386篇 |
1970年 | 344篇 |
1969年 | 373篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
E J García Fernández R Mara?ón C Maroto E Maroto C Seri?á J L Delcán 《Revista espa?ola de cardiología》1991,44(2):115-118
We present 5 patients with cyanotic congenital heart disease in whom a pulmonary valvuloplasty was performed as palliative therapy. The patients symptoms were hypoxemic spells, very low oxygen saturation and no weight gain. The oxygenation improved and symptoms disappeared. We believe that in properly selected patients this technique represents a good therapeutic modality. 相似文献
142.
P Férnandez-Calle J A Molina F J Jiménez-Jiménez A Vázquez M Pondal P J García-Ruiz D G Urra J Domingo R Codoceo 《Neurology》1992,42(5):1064-1066
To elucidate the possible role of vitamin E in the pathogenesis of Parkinson's disease (PD), we compared serum levels of alpha-tocopherol (vitamin E), measured by high-performance liquid chromatography, and the vitamin E/cholesterol ratio of 42 Parkinson's disease (PD) patients using their spouses as the control group. The serum levels of vitamin E did not differ significantly between the groups (13.84 +/- 0.56 micrograms/ml for PD and 14.80 +/- 0.57 micrograms/ml for controls), nor did the vitamin E/cholesterol ratio (0.64 +/- 0.03 for both groups). There was no influence of antiparkinsonian therapy on vitamin E or the vitamin E/cholesterol ratio. Serum levels of the vitamin E and vitamin E/cholesterol ratio did not correlate with age, age at onset, scores of the Unified Parkinson's Disease Rating Scale or the Hoehn and Yahr staging in the PD group. These results suggest that serum vitamin E concentrations do not play a role in the pathogenesis of PD. 相似文献
143.
144.
C Villarreal-Urenda C Cano-Domínguez V Zamalloa-Torres L Ruiz-Maya F Olivares-López 《Gaceta médica de México》1991,127(2):133-136
This prospective study was carried out on thirty patients transfused with blood or blood products, by ten (33.3%) posttransfusion hepatitis was diagnosed; this is 15.75 cases per 1,000 U transfused. Four patients developed jaundice; six remained asymptomatic. In nine patients (90%) non-A, non-B hepatitis was diagnosed and one (10%) case was classified as hepatitis B. Two patients with non-A, non-B hepatitis developed chronic hepatitis, corroborated through percutaneous liver biopsy. 相似文献
145.
J Sabán J L Rodríguez-García J Gil J R País S Medina 《The Netherlands journal of medicine》1991,39(5-6):350-352
The aetiology of porphyria cutanea tarda (PCT) has not been elucidated, but the possibility of an autoimmune mechanism has been proposed. We report a case of an unknown clinical combination of PCT with autoimmune hypothyroidism, alopecia universalis and vitiligo with thyroid and parietal cell circulating antibodies. This is highly suggestive of underlying autoimmune damage in this patient. 相似文献
146.
To determine the therapeutic activity on regional myocardial function of nifedipine intravenous administration (0.16 mg/kg) during short term myocardial induced ischemia, we used 6 mongrel dogs anesthetized and intubated those who we have implanted 3 pairs of ultrasonic crystals in the subendocardial layer. Utilizing an open chest canine model we performed total 1 minute and partial 2 minutes 30 seconds alternative obstructions, controlled with electromagnetic flowmeters in the anterior descending (AD) and circumflex (Cx) coronary arteries before and after drug administration. During the 70-80% obstructions we have shown a significant improvement in segment shortening, reduced by ischemia, in the ischemic and peri-ischemic zone. The ischemic markers, per cent increment of end diastolic length (% IEDL) and per cent increment of end systolic length (% IESL), have shown significant improvement during partial obstructions in the ischemic and peri-ischemic zone. After total obstructions the improvement on regional myocardial function is less marked and limited to ischemic zone. 相似文献
147.
Christopher Del Mar FRACGP FAFPHM Vivienne O'Connor FRACOG 《The Australian & New Zealand journal of obstetrics & gynaecology》1994,34(1):35-38
Summary: We questioned 229 general practitioners (GPs), 288 women who had recently delivered babies in public hospitals, 26 public hospital doctors, and 33 midwives in South Brisbane. Shared antenatal care was undertaken by 84% of mothers, and recently provided by 88% GPs. Mothers valued having sufficient time with their antenatal clinician, continuity of care, and short waiting and travel times. They preferred a GP to provide antenatal care, and a hospital midwife to deliver them. GPs were interested in providing even more obstetric care - one third in providing intrapartum care - and in gaining continuing education in obstetrics. Hospital doctors and midwives were supportive of women choosing the personnel to deliver them, and of an increased GP and midwife role in public hospital obstetrics, but unenthusiastic about home deliveries. There is widespread support for an increased role for GPs in public obstetrics. 相似文献
148.
149.
Juan F López-Giménez Laurence H Tecott José M Palacios Guadalupe Mengod M Teresa Vilaró 《Journal of neuroscience research》2002,67(1):69-85
Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors. 相似文献
150.
R Matorras J Diez M Saez F Montoya G Aranguren F J Rodríguez-Escudero 《International journal of gynaecology and obstetrics》1991,36(4):323-327
Two pregnancies in a patient with a fixed-rate pacemaker are reported. The first pregnancy was uneventful. The second had no maternal complications either. A moderate tachysystolia was detected during the second period. The newborn was delivered with forceps applied under spinal anesthesia. Newborn infant evolution presented no hazards, but umbilical cord analysis revealed a severe acidosis, in spite of a normal scalp analysis 45 min earlier. Epidural anesthesia is recommended for such patients. 相似文献