全文获取类型
收费全文 | 76838篇 |
免费 | 5992篇 |
国内免费 | 2572篇 |
专业分类
耳鼻咽喉 | 1095篇 |
儿科学 | 1149篇 |
妇产科学 | 1067篇 |
基础医学 | 10133篇 |
口腔科学 | 1845篇 |
临床医学 | 8184篇 |
内科学 | 12480篇 |
皮肤病学 | 1703篇 |
神经病学 | 4607篇 |
特种医学 | 3585篇 |
外国民族医学 | 7篇 |
外科学 | 8215篇 |
综合类 | 7507篇 |
现状与发展 | 14篇 |
一般理论 | 10篇 |
预防医学 | 5342篇 |
眼科学 | 1541篇 |
药学 | 7945篇 |
36篇 | |
中国医学 | 3245篇 |
肿瘤学 | 5692篇 |
出版年
2024年 | 170篇 |
2023年 | 767篇 |
2022年 | 2157篇 |
2021年 | 3144篇 |
2020年 | 2064篇 |
2019年 | 2144篇 |
2018年 | 2405篇 |
2017年 | 2177篇 |
2016年 | 2492篇 |
2015年 | 3646篇 |
2014年 | 4181篇 |
2013年 | 4912篇 |
2012年 | 6945篇 |
2011年 | 6961篇 |
2010年 | 4640篇 |
2009年 | 3718篇 |
2008年 | 4753篇 |
2007年 | 4439篇 |
2006年 | 3962篇 |
2005年 | 3538篇 |
2004年 | 2845篇 |
2003年 | 2602篇 |
2002年 | 2216篇 |
2001年 | 1643篇 |
2000年 | 1351篇 |
1999年 | 955篇 |
1998年 | 465篇 |
1997年 | 380篇 |
1996年 | 274篇 |
1995年 | 250篇 |
1994年 | 226篇 |
1993年 | 175篇 |
1992年 | 304篇 |
1991年 | 284篇 |
1990年 | 237篇 |
1989年 | 221篇 |
1988年 | 187篇 |
1987年 | 158篇 |
1986年 | 146篇 |
1985年 | 121篇 |
1984年 | 79篇 |
1983年 | 73篇 |
1982年 | 48篇 |
1979年 | 87篇 |
1978年 | 56篇 |
1975年 | 67篇 |
1974年 | 47篇 |
1972年 | 49篇 |
1971年 | 59篇 |
1970年 | 43篇 |
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
31.
32.
G. P. Leese R. T. Jung C. Guthrie† N. Waugh† M. C. K. Browning‡ 《Clinical endocrinology》1992,37(6):500-503
OBJECTIVE: Patients on L-thyroxine with a 'suppressed' TSH (< 0.05 mU/l) were compared to those in whom TSH was detectable but not elevated (0.05-4.0 mU/l), with regard to morbidity data. DESIGN: Biochemical data from Tayside Thyroid Register was matched to hospital admissions data obtained from Health Board Statistics. PATIENTS: The patients were identified from those registered on the computerized Tayside Register. MEASUREMENTS: Serum T4 and TSH assays, clinical assessment scores, and admission records with regard to ischaemic heart disease, overall fractures, fractured neck of femur and breast carcinoma. RESULTS: Over one year, 1180 patients on thyroxine replacement had clinical and biochemical assessment; 59% had a suppressed TSH and 38% 'normal' TSH. Patients with a suppressed TSH exhibited higher median serum thyroxine levels (146 nmol/l, range 77-252 vs 119 nmol/l, 58-224; P < 0.001). Patients under the age of 65 years on L-thyroxine had an increased risk of ischaemic heart disease compared to the general population (female 2.7 vs 0.7%, P < 0.001; male 6.4 vs 1.7%, P < 0.01), but the risk was no different between those with suppressed and normal TSH. There was no increase in risk for overall fracture, fractured neck of femur or breast carcinoma in those on thyroxine with suppressed or normal TSH. CONCLUSION: Patients under the age of 65 years on L-thyroxine had an increased risk of ischaemic heart disease. There was no excess of fractures in patients on L-thyroxine even if the TSH is suppressed. 相似文献
33.
34.
3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. MCPD has been reported genotoxic in vitro, and reproductive toxicity and carcinogenicity in rats. To evaluate the immunomodulatory effect of MCPD on murine splenocyte and macrophage in vitro, we investigated splenocyte blastogenesis by concanavalin A (Con A), anti-CD3, and lipopolyssacharide (LPS), the production of cytokines from splenocyte, and the activity of mouse peritoneal macrophages. There was a significant decrease in lymphocyte blastogenesis to Con A or anti-CD3 at subtoxic dose of MCPD. A significant decrease in splenocyte blastogenesis to LPS was also observed. The production level of interferon (IFN)-gamma on splenocyte culture with Con A was significantly reduced at the higher concentration than 1.0mM of MCPD. The levels of interleukin (IL)-4 and IL-10 were also decreased at high concentrations of MCPD. There was a significant decrease in production of nitric oxide (NO) by peritoneal macrophages treated with MCPD. MCPD also inhibits tumor necrosis factor (TNF)-alpha production of stimulated macrophages. These results indicate that MCPD might be able to reduce the functionality of lymphocytes and peritoneal macrophages in vitro. 相似文献
35.
Bruce E. Lewis Colin Sumida Ming H. Hwang Henry S. Loeb 《Catheterization and cardiovascular interventions》1992,26(4):295-299
Four selected cases of emergent IABP insertion in PV patients are presented. After angiographic documentation of critical iliac stenosis, conservative peripheral angioplasty was performed prior to IABP insertion. No patient experienced a peripheral ischemic event associated with IABP use. © 1992 Wiley-Liss, Inc. 相似文献
36.
E Jung H-S Won S-K Kim J-Y Shim P R Lee A Kim J K Kim 《Ultrasound in obstetrics & gynecology》2006,27(5):562-565
Fetal thrombosis of the dural sinus is an extremely rare congenital cerebrovascular condition that is potentially fatal. We report a case of dural sinus thrombosis diagnosed by prenatal ultrasonography and fetal magnetic resonance imaging (MRI) in the second trimester. The thrombosis showed partial resolution during pregnancy and resolved spontaneously after birth without neurological complications. This is the first report of spontaneous postnatal resolution, and may provide helpful information on the natural history and prenatal counseling of fetal thrombosis of the dural sinus. 相似文献
37.
Marcelo Miranda MD Claudia Castiglioni MD Beat M. Frey MD Martin Hergersberg PhD Adrian Danek MD Hans H. Jung MD 《Movement disorders》2007,22(9):1358-1361
The X‐linked McLeod neuroacanthocytosis syndrome strongly resembles Huntington's disease and has been reported in various countries world‐wide. Herein, we report two Chilean brothers with predominant psychiatric features at disease onset including schizophrenia‐like psychosis and obsessive compulsive disorder. Molecular genetic analysis revealed a small deletion in the XK gene (938‐942delCTCTA), which has been already described in a North American patient of Anglo‐Saxon descent and a Japanese family, presenting with seizures, muscle atrophy or chorea yet absence of psychiatric features. These findings argue against a founder effect and indicate a profound phenotypic variability associated with the 938‐942delCTCTA deletion. Our report supports the inclusion of McLeod syndrome in the differential diagnosis of Huntington's disease as well as acute psychosis in male subjects. © 2007 Movement Disorder Society 相似文献
38.
电视硬质气管镜治疗大气道良性肿瘤 总被引:4,自引:4,他引:0
目的探讨电视硬质气管镜在大气道良性肿瘤治疗中的价值.方法2002年9月~2005年4月,我院应用电视硬质气管镜治疗大气道良性肿瘤7例,其中气管1例,隆突1例,左主支气管3例,右主支气管2例.手术采用静脉全身麻醉,喷射通气供氧,探查评估气道后,首先冷冻或电凝肿瘤,破坏肿瘤血供,再以活检钳分块取出,蒂部采用冷冻或氩气凝固处理;对于宽蒂肿瘤,内镜下将肿瘤主体清除后中转开胸行气管局部切除吻合术.结果7例手术均顺利,无一例死亡和严重并发症发生.6例气管窄蒂良性肿瘤镜下完整摘除,1例气管膜部宽蒂平滑肌瘤先内镜清除肿瘤主体后中转开胸行气管局部切除.术后病理为错构瘤2例,平滑肌瘤3例,嗜酸性肉芽肿性腺瘤1例,炎症组织1例.7例随访3~36个月,平均17.3月,无肿瘤复发.结论电视硬质气管镜治疗大气道良性肿瘤安全可靠. 相似文献
39.
通过动物痛行为反应(缩足反射)确定局部和鞘内应用川芎嗪(TMP)对ATP等P2X受体激动剂所致大鼠足底急性伤害性行为反应的影响。P2X3受体拮抗剂TNP-ATP(0.3μmol/L)明显抑制P2X受体激动剂ATP(1μmol/L)或α,β-meATP(0.6μmol/L)引起的大鼠足底急性伤害性反应。大鼠足底局部应用TMP(0.1-10mmol/L)剂量依赖性地对ATP(1μmol/L)或α,β-meATP(0.6μmol/L)引起的伤害性反应具有抑制作用。鞘内应用TMP(50mmol/L)对ATP(1μmol/L)或α,β-meATP(0.6μmol/L)引起的伤害性反应具有抑制作用。结果表明,TMP可通过阻断P2X3受体介导的伤害性兴奋传入抑制P2X受体激动剂引起的大鼠足底急性伤害性反应。 相似文献
40.
Weijiang Zhao Fang Yuan Guilin Li Zhongfang Shi Yun Cui Yazhuo Zhang Zhongcheng Wang 《中国神经再生研究》2007,2(5):276-280
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe.
OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats.
DESIGN: Observational contrast animal study.
SETTING: Beijing Neurosurgical Institute.
MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan.
METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin.
MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue.
RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES.
CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe. 相似文献