全文获取类型
收费全文 | 69470篇 |
免费 | 5100篇 |
国内免费 | 311篇 |
专业分类
耳鼻咽喉 | 728篇 |
儿科学 | 1929篇 |
妇产科学 | 1455篇 |
基础医学 | 8202篇 |
口腔科学 | 1619篇 |
临床医学 | 6887篇 |
内科学 | 14652篇 |
皮肤病学 | 954篇 |
神经病学 | 5643篇 |
特种医学 | 2278篇 |
外国民族医学 | 1篇 |
外科学 | 11320篇 |
综合类 | 1340篇 |
一般理论 | 40篇 |
预防医学 | 5175篇 |
眼科学 | 2495篇 |
药学 | 4764篇 |
1篇 | |
中国医学 | 170篇 |
肿瘤学 | 5228篇 |
出版年
2023年 | 395篇 |
2022年 | 647篇 |
2021年 | 1435篇 |
2020年 | 899篇 |
2019年 | 1322篇 |
2018年 | 1565篇 |
2017年 | 1110篇 |
2016年 | 1292篇 |
2015年 | 1497篇 |
2014年 | 2130篇 |
2013年 | 2903篇 |
2012年 | 4406篇 |
2011年 | 4566篇 |
2010年 | 2614篇 |
2009年 | 2368篇 |
2008年 | 4090篇 |
2007年 | 4111篇 |
2006年 | 3991篇 |
2005年 | 4089篇 |
2004年 | 4010篇 |
2003年 | 3627篇 |
2002年 | 3369篇 |
2001年 | 1408篇 |
2000年 | 1241篇 |
1999年 | 1241篇 |
1998年 | 812篇 |
1997年 | 646篇 |
1996年 | 559篇 |
1995年 | 556篇 |
1994年 | 464篇 |
1993年 | 431篇 |
1992年 | 730篇 |
1991年 | 669篇 |
1990年 | 593篇 |
1989年 | 557篇 |
1988年 | 510篇 |
1987年 | 495篇 |
1986年 | 477篇 |
1985年 | 504篇 |
1984年 | 485篇 |
1983年 | 463篇 |
1982年 | 509篇 |
1981年 | 436篇 |
1980年 | 417篇 |
1979年 | 314篇 |
1978年 | 287篇 |
1977年 | 304篇 |
1976年 | 261篇 |
1974年 | 210篇 |
1973年 | 220篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Surgical treatment of brain metastases from renal cell carcinoma 总被引:1,自引:0,他引:1
R A Badalament R W Gluck G Y Wong C Gnecco E Kreutzer H W Herr W R Fair J H Galicich 《Urology》1990,36(2):112-117
Between January 1976 and December 1986, 22 patients with renal cell carcinoma underwent surgical resection of brain metastases at Memorial Sloan-Kettering Cancer Center. Ten of the patients had metastases limited to the brain and 12 also had extracranial metastases. Twenty patients received external radiotherapy. Five had craniotomy after failing radiation therapy and 15 had adjuvant radiotherapy. Two patients died within thirty days following craniotomy; the median survival of the remaining 20 patients was 20.9 +/- 6.8 months calculated according to a Weibull survival model. Variables examined in relation to survival included absence or presence of extracranial metastases at time of craniotomy, time interval between nephrectomy and diagnosis of cerebral metastases, neurologic status prior to craniotomy, location of the brain tumor, and patient age. None of the variables was significant at the 10 percent level by the Weibull analysis. However, three favorable prognostic factors, namely metachronous brain metastasis more than one year after nephrectomy, minimal or no neurologic deficit at time of craniotomy, and infratentorial lesions show a trend toward improved survival with p less than 0.20. The data suggest that surgical resection of a single and occasionally multiple brain metastases is warranted in selected patients with renal cell carcinoma. 相似文献
52.
53.
Andrew K. C. Lam Abby Lam Jessie Charm Kwai-mui Wong 《Ophthalmic & physiological optics》2005,25(2):162-167
PURPOSE: This study compared the near phoria measurement using the Bernell muscle balance card with and without prism neutralization, using both trial frame and phoropter correction, and compared with the conventional Maddox rod method. METHODS: Forty young normal Chinese adults had their near phoria measured with trial frame correction using the conventional muscle balance card method (method 1). Any deviation was compensated with a prism bar as an alternative approach (method 2). The conventional Maddox rod method (method 3) was also carried out for comparison. These three methods were repeated with phoropter correction and considered as methods 4, 5 and 6. RESULTS: The phorias obtained from these six methods were not significantly different from each other (repeated measures anova, p > 0.05). More than half of the subjects were exophoric. Although the difference in phoria was not significant, phoria measurement using phoropter correction yielded a greater coefficient of variation. CONCLUSIONS: Near phoria measurement using the muscle balance card conducted with trial frame correction was less variable, and was also more natural and similar to a real reading situation. The use of prism for compensation did not affect the phoria results. Exophoria seems to be more common than esophoria in young Chinese adults. 相似文献
54.
55.
Brattleboro rats manifest chronic diabetes insipidus as a result of the genetic deficiency of hypothalamic vasopressin. When basal hypothalamic tissue derived from adult F344 rats was implanted as cell suspensions or tissue blocks in the supraoptic regions of these animals, concentration of urine together with reduced urine output and water intake was observed in some animals. Histologic examination of the grafted brains from the responding animals revealed neuronal cells at the implant sites and vasopressin-staining fibers in the median eminence. This study demonstrates the feasibility of the grafting of adult cerebral tissues to correct a genetic hormonal deficiency. 相似文献
56.
57.
58.
59.
Surgical treatment of lymph nodes with metastatic melanoma from unknown primary site 总被引:1,自引:0,他引:1
To determine the prognosis of patients with lymph node metastases from an unknown primary melanoma, we retrospectively reviewed the clinicopathologic features of 188 such patients treated from 1971 through 1986 and compared their records with those of patients with clinical stage II melanoma with known primary lesions. Patients with lymph node metastases from an unknown primary melanoma represented 4.6% of all patients with melanoma treated during that period. The five- and ten-year survival rates were 42% and 40%, respectively (median, 37 months). When stratified by number of tumor-containing lymph nodes, there was no significant difference in survival between patients with an unknown primary melanoma and lymph node metastases and those with clinical stage II melanoma and known primary sites. The prognosis of the former patients is no worse than that of patients with lymph node metastases from a known primary site and should be treated in a comparable manner. 相似文献
60.