全文获取类型
收费全文 | 34571篇 |
免费 | 1672篇 |
国内免费 | 150篇 |
专业分类
耳鼻咽喉 | 422篇 |
儿科学 | 671篇 |
妇产科学 | 602篇 |
基础医学 | 4718篇 |
口腔科学 | 1224篇 |
临床医学 | 2694篇 |
内科学 | 8143篇 |
皮肤病学 | 862篇 |
神经病学 | 2520篇 |
特种医学 | 1341篇 |
外科学 | 5426篇 |
综合类 | 232篇 |
一般理论 | 2篇 |
预防医学 | 1205篇 |
眼科学 | 557篇 |
药学 | 2377篇 |
中国医学 | 60篇 |
肿瘤学 | 3337篇 |
出版年
2022年 | 377篇 |
2021年 | 649篇 |
2020年 | 310篇 |
2019年 | 470篇 |
2018年 | 647篇 |
2017年 | 475篇 |
2016年 | 527篇 |
2015年 | 613篇 |
2014年 | 794篇 |
2013年 | 907篇 |
2012年 | 1427篇 |
2011年 | 1552篇 |
2010年 | 847篇 |
2009年 | 814篇 |
2008年 | 1409篇 |
2007年 | 1464篇 |
2006年 | 1525篇 |
2005年 | 1549篇 |
2004年 | 1512篇 |
2003年 | 1417篇 |
2002年 | 1434篇 |
2001年 | 1236篇 |
2000年 | 1396篇 |
1999年 | 1222篇 |
1998年 | 426篇 |
1997年 | 298篇 |
1996年 | 312篇 |
1995年 | 291篇 |
1994年 | 255篇 |
1993年 | 243篇 |
1992年 | 805篇 |
1991年 | 762篇 |
1990年 | 688篇 |
1989年 | 704篇 |
1988年 | 679篇 |
1987年 | 672篇 |
1986年 | 676篇 |
1985年 | 603篇 |
1984年 | 434篇 |
1983年 | 351篇 |
1979年 | 339篇 |
1978年 | 239篇 |
1977年 | 202篇 |
1975年 | 199篇 |
1974年 | 233篇 |
1973年 | 208篇 |
1972年 | 197篇 |
1971年 | 210篇 |
1970年 | 204篇 |
1969年 | 225篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Yutaka Ejima Yoko Hasegawa Satoru Sanada Noriyuki Miyama Ryo Hatano Tomohiro Arata Michiko Suzuki Itsuro Kazama Akira Sato Susumu Satomi Wataru Hida Mitsunobu Matsubara 《Hypertension research》2006,29(4):261-267
Since the prevalence and clinical characteristics of young-onset hypertension are still to be elucidated, we performed targeted-screening at an annual university health check-up for two consecutive years. Out of 16,464 subjects in 2003 and 17,032 in 2004 that were aged less than 30 years, 22 and 26 students (all males) exhibited high blood pressure (BP), respectively, on three occasions during casual BP measurements at the Tohoku University Health Center (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively). These students were asked to measure their BP at home, and 9 subjects in total were diagnosed as having essential hypertension (EH). The remaining students were diagnosed as having white coat hypertension (WCH). In 8 out of 9 EH students, their father and/or mother had also been treated with antihypertensive medication. Adjustment by attendance ratio for each BP measurement suggested that the incidence of EH was around 0.1% and that of hypertension (EH and WCH) was around 0.5% in university students aged less than 25 years, since most of the subjects and hypertensive students were between 18 and 24 years old. Body mass index of the EH, which was more than 25 kg/m2 (overweight), was significantly higher than that with WCH. In conclusion, the combination of repeated casual BP measurements and home BP effectively identified young-onset EH. The clinical parameters indicated that male gender, genetic background, and excessive weight were risk factors for young-onset hypertension. 相似文献
52.
Shigeo Nakamura Takashi Koshikawa Tsuneko Sato Kayoko Hayashi Taizan Suchi 《Pathology international》1992,42(10):745-750
We describe a 54-year-old woman with primary pulmonary adenocarcinoma showing a characteristic papillary architecture and prominent cilia formation. Immunohistochemically, the tumor cells were positive for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and Leu Ml, and negative for lactoferrin and surfactant apoprotein. An ultrastructural study also indicated differentiation toward bronchial surface epithelial cells. To our knowledge, this type of neoplasm has not been reported as peripheral-type adenocarcinoma of the lung. Acta Pathol Jpn 42: 745–750, 1992. 相似文献
53.
Enzymes induced by ethanol differently affect the pharmacokinetics of trichloroethylene and 1,1,1-trichloroethane. 总被引:1,自引:0,他引:1 下载免费PDF全文
This study was undertaken to clarify the effect of enzymes induced by ethanol consumption on the pharmacokinetics of trichloroethylene (TRI, a highly metabolised substance) and 1,1,1-trichloroethane (1,1,1-TRI, a poorly metabolised substance). Rats maintained on a control liquid diet or a liquid diet containing ethanol (2 g/day/rat) for not less than three weeks were exposed to either TRI (50, 100, 500, and 1000 ppm) or 1,1,1-TRI (50, 100, and 500 ppm) by inhalation for six hours and the concentration of each compound in the blood and the urinary excretion of metabolites (trichloroethanol and trichloroacetic acid) were measured over several hours. Ethanol, which increased the in vitro metabolism of both compounds about fivefold, enhanced the in vivo metabolism of TRI only at high levels of exposure (marginally at 500 and considerably at 1000 ppm), whereas the metabolism of 1,1,1-TRI was enhanced at all concentrations tested. Moreover, there was a definite difference in the effect of induction of enzymes between the two solvents: the enhanced metabolism of TRI in vivo was shown by a decrease in the blood concentration of TRI as well as by an increase in the urinary excretion of its metabolites, whereas that of 1,1,1-TRI was shown by an increase in the urinary excretion of its metabolites alone. These results suggest that the induction of enzymes differentially affects the pharmacokinetics of TRI and 1,1,1-TRI in human occupational exposure: TRI metabolism may be increased only at concentrations much higher than the current occupational exposure limit (mostly 50 ppm), whereas 1,1,1-TRI metabolism may be increased at an exposure similar to occupational exposure. 相似文献
54.
55.
56.
H. Kitamura T. Shioiri M. Itoh Y. Sato K. Shichiri & T. Someya 《Journal of intellectual disability research : JIDR》2007,51(10):812-820
Background Evidence suggests that, as a group, patients with schizophrenia have intellectual deficits that may precede the manifestation of psychotic symptoms; however, how successfully intelligence tests are able to discriminate schizophrenia from other psychotic disorders has yet to be investigated in detail. Methods Using Wechsler Adult Intelligence Scale – Revised (WAIS‐R) data for 55 inpatients with schizophrenia and 28 inpatients with non‐schizophrenic psychotic disorders (NSPD) (schizophreniform disorder, brief psychotic disorder, delusional disorder, psychotic disorder due to a general medical condition, and psychotic disorders not otherwise specified), intelligence performance was compared between schizophrenia and NSPD and among different subtypes of schizophrenia. Results There were no significant differences in intelligence quotient (IQ), verbal IQ (VIQ) and performance IQ (PIQ) discrepancy, and subtest scores of WAIS‐R between the patients with schizophrenia and those with NSPD. These diagnostic groups were not discriminated well by any WAIS‐R variables. Schizophrenia patients with prominent negative symptoms, on the other hand, had a significantly larger IQ discrepancy (VIQ > PIQ) than those without prominent negative symptoms and NSPD patients. Intelligence performance in schizophrenia did not differ with respect to diagnostic subtypes and longitudinal courses. Conclusions The current study failed to show diagnostic usefulness of WAIS‐R in discriminating schizophrenia and other psychoses. A diagnosis of schizophrenia does not significantly impact intellectual deficits in psychotic disorders. 相似文献
57.
58.
59.
Radiographic studies of three cases of hypoplasia of the humeral trochlea were done. Several other anomalies were also detected, including a hypoplastic capitellum in case 2, a hyperplastic radial head in cases 2 and 3, and bulging of the loose joint capsule in case 3. Operations in cases 1 and 3, disclosed that ganglions and fibrous septa compressed the ulnar nerve. The cause of ulnar nerve palsy in patients with hypoplasia of the humeral trochlea is thought to be associated with the high incidence of ganglions in hypoplastic elbow joints. The ganglion may play a role. 相似文献
60.