全文获取类型
收费全文 | 89949篇 |
免费 | 7993篇 |
国内免费 | 5571篇 |
专业分类
耳鼻咽喉 | 989篇 |
儿科学 | 1062篇 |
妇产科学 | 692篇 |
基础医学 | 9624篇 |
口腔科学 | 1377篇 |
临床医学 | 10109篇 |
内科学 | 11884篇 |
皮肤病学 | 969篇 |
神经病学 | 4323篇 |
特种医学 | 4184篇 |
外国民族医学 | 27篇 |
外科学 | 10929篇 |
综合类 | 17103篇 |
现状与发展 | 19篇 |
一般理论 | 8篇 |
预防医学 | 6614篇 |
眼科学 | 2058篇 |
药学 | 9382篇 |
89篇 | |
中国医学 | 5514篇 |
肿瘤学 | 6557篇 |
出版年
2024年 | 255篇 |
2023年 | 1062篇 |
2022年 | 2795篇 |
2021年 | 3775篇 |
2020年 | 2938篇 |
2019年 | 2480篇 |
2018年 | 2647篇 |
2017年 | 2560篇 |
2016年 | 2586篇 |
2015年 | 3897篇 |
2014年 | 5075篇 |
2013年 | 5241篇 |
2012年 | 7654篇 |
2011年 | 7891篇 |
2010年 | 5979篇 |
2009年 | 5118篇 |
2008年 | 5808篇 |
2007年 | 5613篇 |
2006年 | 5376篇 |
2005年 | 4588篇 |
2004年 | 3421篇 |
2003年 | 3428篇 |
2002年 | 2978篇 |
2001年 | 2169篇 |
2000年 | 1685篇 |
1999年 | 1236篇 |
1998年 | 748篇 |
1997年 | 769篇 |
1996年 | 551篇 |
1995年 | 463篇 |
1994年 | 386篇 |
1993年 | 231篇 |
1992年 | 299篇 |
1991年 | 249篇 |
1990年 | 197篇 |
1989年 | 161篇 |
1988年 | 161篇 |
1987年 | 147篇 |
1986年 | 134篇 |
1985年 | 111篇 |
1984年 | 46篇 |
1983年 | 46篇 |
1982年 | 38篇 |
1979年 | 48篇 |
1975年 | 28篇 |
1974年 | 43篇 |
1973年 | 35篇 |
1969年 | 36篇 |
1967年 | 32篇 |
1966年 | 33篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
Cleft lip and palate, sensorineural deafness, and sacral lipoma in two brothers: a possible example of the disorganisation mutant. 总被引:1,自引:0,他引:1 下载免费PDF全文
We report two brothers of Chinese origin who have an apparently unique syndrome of cleft lip/palate, profound sensorineural deafness, and a sacral lipoma. Additional findings which were not common to both were aberrant digital appendages on the heel and thigh of one boy and an anterior sacral meningocele and dislocated hip in the other. Intelligence is normal in both. Both boys suffer from functional constipation but biopsy studies showed no evidence of Hirschsprung's disease. The parents, who are normal, are not related. Inheritance is probably autosomal or X linked recessive. A possible link with the disorganisation mouse mutant is discussed. 相似文献
112.
Zheng Qi-xin Zhu Tong-bai Du Jing-yuan Hong Guang-xiang Li Shi-pu Yan Yun-hua Zhang En-dang 《华中科技大学学报(医学英德文版)》1992,12(3):173-178
Summary The authors have prepared the artificial bone of porous tricalcium phosphate ceramics according to an appropriate formula
and manufacturing technology. Physical and chemical testing shows that it possesses several distinguishing features: the communicating
pores and macro/micropores; mean pore size, 380 μm (from 240 μm to 510 μm); porosity, 46.4 %; and compressive strength, 97.4
kg/cm2. It consists of CaO (49.09 %) and P2O5 (48.84 %). The testing of its biocompatibility shows that it is devoid of systemic or local toxicity, and free of irritation
or foreign body response in tissues, and it does not result in hemolysis or mutation. The new bone readily grows into its
pores with direct contact to the implanted material. 11 cases of bone defects were treated with this artificial bone with
satisfactory results. 相似文献
113.
直肠癌患者手术前后凝血状态变化的研究 总被引:1,自引:0,他引:1
目的:通过研究直肠癌患者凝血与纤溶系统的变化,观察其与手术切除与否、淋巴结转移、细胞分化程度等的关系。方法:选取直肠癌患者58例,于术前及术后两周检测PAGT、PT、APTT、TFPI、D-二聚体、t-PA:a等指标;同期52例非肿瘤病人作为对照组。结果:直肠癌患者较对照组血小板聚集增强(P<0.05),凝血酶原时间、活化部分凝血活酶时间明显缩短,组织因子途径抑制物降低(P<0.05),D-二聚体和t-PA:a显著升高(P<0.01),存在淋巴结转移和低分化腺癌者尤为明显(P<0.05或P<0.01),手术切除后有所改善。结论:直肠癌患者处于高凝和纤溶亢进状态,在淋巴结转移和癌细胞分化差的病人中尤为明显;应用抗凝和抗纤溶药物可能对直肠癌的预防有一定作用。 相似文献
114.
小包装全氟丙烷气体动力学实验研究 总被引:1,自引:0,他引:1
为检验塑料小包装全氟丙烷气体(C3F8)在不同包装和储存方法时浓度变化,将装有5~7mlC3F8的聚氯乙烯小袋,根据不同储藏温度和外包装方法随机分成四组:(1)22℃聚乙烯外包装,(2)36℃聚乙烯外包装,(3)22℃铝箔真空外包装,(4)-29℃聚乙烯外包装;每一组C3F8小袋气体存放一定时间后,应用气相色谱分析方法进行浓度测量。结果:第3组C3F8浓度最高和稳定,第2组浓度随放置时间降低最明显,第4组是临床应用气体的储藏和包装方法,其30天样本浓度和第3组相等,但放置一年时浓度降低。结果显示:塑料小包装C3F8予以铝箔真空外包装是一种可行的方法,利于C3F8运输和普及;聚乙烯外包装的C3F8,应放在-29℃保存,时间不超过一年。 相似文献
115.
The subdivisions of the sacral intermediolateral nucleus (IML) of the cat have been studied by using a double-labeling technique of retrograde Fluoro-gold (FG) and wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) tracing. The parasympathetic preganglionic neurons (PGNs) that were labeled by the FG injected into the pelvic nerve formed a ‘V’-shaped column known as the sacral parasympathetic nucleus (SPN) in the sacral IML. The neurons that were labeled by the WGA-HRP applied to the lateral parabrachial nucleus (PBL) formed an elongated spindle-shaped column extending throughout the IML of the sacral segments. We designated it by the name of sacral visceral sensory nucleus (SVSN). These findings indicate that the sacral IML of the cat contain two distinct subdivisions, SPN and SVSN. 相似文献
116.
J. Pfisterer F. Kommoss W. Sauerbrei B. Baranski M. Kiechle H. Ikenberg A. Du Bois & A. Pfleiderer 《International journal of gynecological cancer》1996,6(1):54-60
In a retrospective study the prognostic significance of nuclear DNA content was investigated, as measured by flow cytometry, of the tumor specimens from 212 women with nonpretreated FIGO stage IB and II cervical cancer. One-hundred and thirty cases (62%) were found to be diploid, whereas 82 (38%) were aneuploid. Univariate analysis of the follow-up data showed an increased relative risk (RR) for recurrence free survival (RFS) for stage II tumors (RR = 1.87, 95% CI: 1.13–3.10, P = 0.015) and for age (RR = 1.52, 95% CI: 0.66–3.52 and RR = 2.35, 95% CI: 1.19–4.65, P = 0.032). Ploidy showed a relative risk of 1.33 (95% CI: 0.83–2.13, NS). In addition, univariate analysis of overall survival (OS) revealed similar results. For the subgroup of patients with primary surgery ( n = 151), positive pelvic nodes (RR = 5.38, 95% CI: 2.70–10.71, P = 0.0001) and parametrial extension (RR = 2.53, 95% CI: 1.24–5.17, P = 0.011) were significant factors for OS after univariate analysis, the estimated effects on RFS were slightly smaller. Multivariate analysis of RFS for the whole study population showed age, histologic grade and stage with a slightly increased risk, but no effect was significant. Ploidy with an RR of 0.97 (95% CI: 0.58–1.62) seems to have no influence on prognosis. For the subgroup with primary surgery, ploidy again failed statistical significance with an RR of 1.20 (95% CI: 0.58–2.49). Our results suggest that abnormalities of the nuclear DNA content in this homogeneous group of patients are associated with clinical and morphological prognosticators, however, ploidy is not an independent prognostic factor for RFS, or for the whole study population or for the subgroup with primary surgery. 相似文献
117.
中西医结合治疗坏死性筋膜炎 总被引:1,自引:0,他引:1
本文积累了1981~1994年近十余年的临床资料,总结了中西医结合治疗坏死性筋膜炎的临床治疗经验。指出坏死性筋膜炎是一种少见的严重的软组织感染,发展迅速,病死率高,应引起临床医生的高度警惕,做出早期诊断是非常必要的。提出了扶正祛邪的中西医结合的整体治疗方案,全身治疗与局部处理相结合。对患处要采取早期,这时的多切口引流,给"邪"以出路。取得良好的疗效。 相似文献
118.
Effect of isoelectric point on biodistribution and inflammation imaging with indium-111-labelled IgG
Caroline I. ten Kate Alan J. Fischman Robert H. Rubin A. J. Fucello D. Riexinger Robert A. Wilkinson Lina Du Ban An Khaw H. William Strauss 《European journal of nuclear medicine and molecular imaging》1990,17(6-8):305-309
Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs. 相似文献
119.
CT导引下肝肾囊肿抽吸硬化治疗 总被引:6,自引:0,他引:6
目的:总结CT导引下肝肾囊肿穿刺抽吸硬化治疗的疗效和操作经验。材料和方法:肝囊肿11,肾囊肿15例,多囊肾1例,囊肿大小为3.5-12cm,均用15cm长20GGreene针穿刺治疗,抽出囊液量为21-550ml,囊液抽净后注入99.7%的无水酒精。结果:治疗后症状均有明显好转或消失,本组随访肝囊肿7例、肾囊肿11例,疗效指数I级1例(多囊肾),Ⅱ级肝肾囊肿各2例,Ⅲ级肝囊肿5例肾囊肿8例。穿刺操作顺利,无严重并发症发生。结论:CT导引下肝肾囊肿抽吸硬化治疗操作简便、创伤小、疗效高可作为替代外科手术的有效的治疗方法,多囊肾的单纯抽吸治疗可明显减轻症状,改善肾功能,是一种较好的治疗手段。 相似文献
120.
利用电渗析和离子交换柱除去原水中的各种杂质可得到去离子水.而去离子水的质量直接决定了医用注射液的质量。通过近二年的实际操作.列出了与去离子质量有关的主要因素,并提出一些相应见解。 相似文献