全文获取类型
收费全文 | 91296篇 |
免费 | 7687篇 |
国内免费 | 5134篇 |
专业分类
耳鼻咽喉 | 999篇 |
儿科学 | 1011篇 |
妇产科学 | 933篇 |
基础医学 | 11084篇 |
口腔科学 | 1372篇 |
临床医学 | 10766篇 |
内科学 | 13287篇 |
皮肤病学 | 1349篇 |
神经病学 | 5140篇 |
特种医学 | 3866篇 |
外国民族医学 | 40篇 |
外科学 | 10074篇 |
综合类 | 13222篇 |
现状与发展 | 18篇 |
一般理论 | 12篇 |
预防医学 | 5973篇 |
眼科学 | 2466篇 |
药学 | 9750篇 |
68篇 | |
中国医学 | 5180篇 |
肿瘤学 | 7507篇 |
出版年
2024年 | 309篇 |
2023年 | 1250篇 |
2022年 | 3370篇 |
2021年 | 4411篇 |
2020年 | 3232篇 |
2019年 | 2787篇 |
2018年 | 3050篇 |
2017年 | 2826篇 |
2016年 | 2868篇 |
2015年 | 4367篇 |
2014年 | 5396篇 |
2013年 | 5286篇 |
2012年 | 7624篇 |
2011年 | 8055篇 |
2010年 | 5273篇 |
2009年 | 4308篇 |
2008年 | 5344篇 |
2007年 | 4966篇 |
2006年 | 4706篇 |
2005年 | 4368篇 |
2004年 | 3067篇 |
2003年 | 2782篇 |
2002年 | 2308篇 |
2001年 | 1887篇 |
2000年 | 1839篇 |
1999年 | 1628篇 |
1998年 | 916篇 |
1997年 | 805篇 |
1996年 | 649篇 |
1995年 | 610篇 |
1994年 | 478篇 |
1993年 | 362篇 |
1992年 | 475篇 |
1991年 | 477篇 |
1990年 | 350篇 |
1989年 | 269篇 |
1988年 | 272篇 |
1987年 | 234篇 |
1986年 | 173篇 |
1985年 | 128篇 |
1984年 | 94篇 |
1983年 | 69篇 |
1982年 | 59篇 |
1981年 | 52篇 |
1980年 | 44篇 |
1979年 | 69篇 |
1978年 | 31篇 |
1977年 | 27篇 |
1975年 | 23篇 |
1973年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 181 毫秒
31.
Matteo Brunelli John N Eble Shaobo Zhang Guido Martignoni Liang Cheng 《Modern pathology》2003,16(10):1053-1059
It has been suggested that gains of chromosomes 7 and 17 and loss of Y occur in renal papillary adenoma and that progression to papillary renal cell carcinoma is marked by gains of additional chromosomes, most frequently 12, 16, and 20. Previous studies have included very few lesions of <5 mm in diameter, a requirement of the present definition of papillary adenoma. Ten papillary adenomas (ranging from 1 to 5 mm in diameter) from autopsy material and 10 surgically resected papillary renal cell carcinomas were studied with fluorescence in situ hybridization in paraffin sections using centromeric probes for chromosomes 7, 12, 16, 17, 20, and Y diluted 1:100 with tDenHyb1 buffer. The signals in 50 to 150 nuclei were counted in each tumor. Controls for all the probes were normal renal tissues from the same patients. Three or more signals per nucleus were frequently observed in papillary adenomas: chromosome 7 (range, 10 to 50%; > or = 30% in 9 of 10), 17 (range, 10 to 47%; > or = 30% in 7), 16 (range, 1 to 63%; > or = 10% in 5), 12 (range, 0 to 32%; > or =10% in 4), and 20 (range, 5 to 49%; > or = 10% in 5). Loss of the Y chromosome was observed in 80 to 90% of nuclei in 9 adenomas from males. Three or more signals were frequent in papillary renal cell carcinomas: chromosome 7 (range, 32 to 63%; > or =30% in 10 of 10), 17 (range, 28 to 61%; > or = 30% in 7), 16 (range, 0 to 45%; > or = 10% in 6), 12 (range, 1 to 37, > or = 10% in 5), 20 (range, 2 to 44%; > or = 10% in 4). No signal for Y was observed in 12 to 88% (> or = 81% in 6) of nuclei in 7 carcinomas from males. Statistical analysis showed no difference between adenomas and carcinomas. Gains of chromosomes 7, 17, 16, 12, and 20 and loss of the Y chromosome occur early in the evolution of papillary renal cell neoplasia in tumors that are only a few millimeters in diameter. Progressive gains of these chromosomes do not appear to correlate with the transition from adenoma to carcinoma. 相似文献
32.
Percutaneous transluminal coronary angioplasty in a patient with paroxysmal nocturnal hemoglobinuria
Ping-Ching Fong Yau-Ting Tai Chu-Pak Lau John Li Florence Hiu-Yee Yap Raymond Liang Albert Kwok-Wai Lie 《Catheterization and cardiovascular interventions》1992,25(2):144-147
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired chronic hemolytic anemia associated with an unusual susceptibility to hemolytic crisis, infection, and venous thrombosis which would be aggravated by a number of factors including surgery. We report a case of PNH undergoing percutaneous transluminal coronary angioplasty and discuss the corresponding perioperative management. 相似文献
33.
Twenty-seven in-patients with obstetric DIC in our hospital from Jan. 1971 to Dec. 1990 were analysed retrospectively. The incidence was 0.12% in the first decade and 0.02%, in the second, showing a difference of significance between them. The most common predisposing factors included amniotic fluid embolism, abruptio placenta and hemorrhagic shock. Bleeding from multi-organs in various extent and coagulation disorders occurred in all those 27 cases. [Besides anti-shock treatment, heparin was employed together with fibrinogen in 4 postpartum and 1 antepartum DIC patients, fibrinogen alone in 8 cases, and hysterectomy in 11 cases. 17 patients were saved and 9 died. It is important that early diagnosis and much attention paid to clinical characteristics together with serial laboratory tests. Key management should include prompt treatment and eradication of predisposing factors. Quick decision spite of to terminate the pregnancy and even hysterectomy should be done in some risks. 相似文献
34.
G K Scriba J A Hower N Y Liang P V Fennessey R T Borchardt 《The Journal of pharmacology and experimental therapeutics》1988,247(2):609-616
The effect of ibopamine (IBO) (SB 7505, SK&F 100168-A), a new drug for the treatment of congestive heart failure, and its active metabolite epinine (EPN) (N-methyldopamine), on the catecholamine content of hypothalamus and brainstem was studied in vitro after monoamine oxidase inhibition with pargyline. IBO and EPN increased levels of epinephrine (EPI) in a concentration- and time-dependent manner in both brain areas without significantly affecting the concentration of other catecholamines. Inhibition of either dopamine beta-hydroxylase, the neuronal EPI and norepinephrine uptake system, or esterase hydrolysis of IBO prevented the increase of EPI, whereas inhibition of phenylethanolamine N-methyltransferase, enzymatic dealkylation or the neuronal dopamine or serotonin uptake system had no influence on the increase of EPI levels. These results suggest that IBO after hydrolysis to EPN can be converted enzymatically to EPI by dopamine beta-hydroxylase in hypothalamus and brainstem. EPN seems to be accumulated into adrenergic and noradrenergic neurons by the high affinity uptake system. Changes in the EPI content of the central nervous system neurons might be responsible for some of the pharmacologic effects of IBO. 相似文献
35.
36.
The immediate, short-term and long-term depressor effects, the immediate effects on cardiac functions in grade II and grade III vascular hypertension, and the effects on angiotensin II in grade III vascular hypertension by acupuncture at otoacupoint Heart were studied in 30 cases of vascular hypertensive patients. The immediate depressor effect of acupuncture at otoacupoint Stomach was also recorded for comparison. It was found that acupuncture at otoacupoint Heart produced marked immediate depressor effect, and the short-term effective rate was 100%, the long-term effective rate was 63.3%, as well as evident immediate effects on cardiac functional activities in grade II and grade III hypertension and marked effects on angiotensin II in grade III hypertension. Acupuncture at otoacupoint Stomach produced no depressor effect on vascular hypertension. 相似文献
37.
男性慢性胃炎患者人格特征初探 总被引:4,自引:0,他引:4
本文采用卡氏十六种人格因素量表,对纤维胃十二肠镜和活体组织病理检查确诊,剔除可能影响调查的疾患之后的56例慢性胃炎患者做了测查,结果与中国男性成人常模对照,提示男性慢性胃炎患者的主要人格特征有:严谨、保守、忧郁、紧张、顺从、依赖、有焦虑倾向,非内向个性,不属于心理不健康人群,而与消化性溃疡个性特征有所不同,但是,矫治其人格缺损及属必要。 相似文献
38.
51例应用Begg正畸技术矫治错畸形,各种类型的牙性及轻度骨性错畸形,均取得满意的效果。对牙轴唇倾并伴有深覆的安氏Ⅱ类错打开咬合、内收前牙的效果尤佳。 相似文献
39.
Ezequiel H Cassinelli Corey Wallach Brett Hanscom Molly Vogt James D Kang 《The spine journal》2006,6(4):428-434
BACKGROUND CONTEXT: Posterior lumbar interbody fusion (PLIF) is a popular method of arthrodesis for surgical treatment of instabilities and degenerative conditions of the spine. With the introduction of threaded titanium cage devices, surgeons began performing PLIF procedures using these cages as stand-alone devices. Complications have been reported, however, including pseudarthrosis with persistent pain. Outcomes after revision surgical treatment for these patients with failed PLIF are not known. PURPOSE: To prospectively evaluate clinical outcomes of revision fusion surgery in patients who previously underwent posterior lumbar interbody fusion with stand-alone metallic cages resulting in pseudarthrosis. STUDY DESIGN/SETTING: Prospective case series. METHODS: Nineteen patients referred to the senior author were evaluated and diagnosed with pseudoarthrosis having previously undergone a PLIF procedure with stand-alone metallic cages. History, physical exam, and imaging studies were performed preoperatively and postoperatively. All underwent revision posterolateral fusion with iliac crest graft and pedicle screw instrumentation. Patient demographics, SF-36, and Oswestry Disability Index (ODI) data were collected prior to surgery and two years postoperatively. RESULTS: Patients undergoing revision fusion surgery were found to have had extensive facetectomies and pseudarthrosis intraoperatively. Outcomes data was collected on eighteen of nineteen patients (95%). Mean clinical follow up was 3.2 years (range 2.5-3.5 years). Seventeen patients (94%) achieved a solid fusion. Improvement was noted in seven of eight SF-36 sub-categories, but was significant only in two (Physical Function and Role Emotional). There was no significant difference in ODI scores. CONCLUSIONS: Pseudarthrosis should be considered in the differential diagnosis if severe symptoms persist in patients who undergo PLIF with stand-alone metallic cages. Successful revision fusion did not always correlate with improved clinical outcomes in these challenging patients undergoing further surgery. Performing PLIF using stand-alone metallic cages, especially after total resection of the facet joints, is not advocated unless supplemental instrumentation is utilized. 相似文献
40.
超声引导下肿瘤内注射^90钇玻璃微球的肝癌综合治疗 总被引:12,自引:0,他引:12
超声引导下对28例肝癌病人进行了肿瘤内注射^90钇玻璃微球(Y-90GT MS)为主的综合性治疗(部分病人配合肿块周边注射无水酒精及门静脉穿刺化疗)。随访2~16个月(平均7.9个月),病人全健在。肿瘤缩小率为91%,其中显著缩小达75%;肿块回声呈致密增强,少数呈混合型或等回声型;肿瘤内及周边血流信号显著减少;原甲胎蛋白升高者13例,11例显著下降,其中6例降至正常;病人症状减轻,全身情况改善。 相似文献