全文获取类型
收费全文 | 1147篇 |
免费 | 92篇 |
国内免费 | 18篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 84篇 |
妇产科学 | 8篇 |
基础医学 | 105篇 |
口腔科学 | 26篇 |
临床医学 | 94篇 |
内科学 | 230篇 |
皮肤病学 | 27篇 |
神经病学 | 20篇 |
特种医学 | 136篇 |
外科学 | 123篇 |
综合类 | 146篇 |
预防医学 | 81篇 |
眼科学 | 14篇 |
药学 | 58篇 |
中国医学 | 39篇 |
肿瘤学 | 63篇 |
出版年
2023年 | 8篇 |
2022年 | 15篇 |
2021年 | 25篇 |
2020年 | 20篇 |
2019年 | 15篇 |
2018年 | 21篇 |
2017年 | 14篇 |
2016年 | 22篇 |
2015年 | 29篇 |
2014年 | 43篇 |
2013年 | 45篇 |
2012年 | 49篇 |
2011年 | 53篇 |
2010年 | 73篇 |
2009年 | 60篇 |
2008年 | 29篇 |
2007年 | 30篇 |
2006年 | 41篇 |
2005年 | 28篇 |
2004年 | 23篇 |
2003年 | 32篇 |
2002年 | 18篇 |
2001年 | 15篇 |
2000年 | 12篇 |
1999年 | 19篇 |
1998年 | 46篇 |
1997年 | 60篇 |
1996年 | 52篇 |
1995年 | 39篇 |
1994年 | 34篇 |
1993年 | 33篇 |
1992年 | 10篇 |
1991年 | 8篇 |
1990年 | 13篇 |
1989年 | 23篇 |
1988年 | 20篇 |
1987年 | 17篇 |
1986年 | 17篇 |
1985年 | 12篇 |
1984年 | 14篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 13篇 |
1979年 | 8篇 |
1977年 | 8篇 |
1976年 | 7篇 |
1974年 | 7篇 |
1973年 | 5篇 |
1969年 | 5篇 |
1958年 | 5篇 |
排序方式: 共有1257条查询结果,搜索用时 0 毫秒
101.
S Ghezzi F Pacciarini S Nozza S Racca SA Mariani E Vicenzi A Lazzarin F Veglia G Tambussi G Poli 《HIV medicine》2010,11(5):349-352
Objective
To investigate the impact of intermittent interleukin‐2 (IL‐2) plus combination antiretroviral therapy (cART) on HIV‐1 entry co‐receptor use.Methods
Primary HIV‐1 isolates were obtained from 54 HIV‐1‐positive individuals at baseline and after 12 months using co‐cultivation of peripheral blood mononuclear cells (PBMC) with activated PBMC of HIV‐negative healthy donors. HIV‐1 co‐receptor use was determined on U87‐CD4 cells.Results
Fourteen out of the 21 (67%) IL‐2‐treated individuals harbouring a primary CCR5‐dependent (R5) HIV‐1 isolate at baseline confirmed an R5 virus isolation after 12 months in contrast to 3 out of 7 (43%) of those receiving cART only. After 12 months, only 1 R5X4 HIV‐1 isolate was obtained from 21 cART+IL‐2‐treated individuals infected with an R5 virus at entry (5%) vs. 2/7 (29%) patients receiving cART alone, as confirmed by a 5‐year follow‐up on some individuals.Conclusions
Intermittent IL‐2 administration plus cART may prevent evolution towards CXCR4 usage in individuals infected with R5 HIV‐1.102.
目的对实验动物皮肤病原真菌2种培养方法进行了比较。方法将采集到的3只皮肤真菌感染病兔样品经由沙氏平皿法和沙氏试管斜面培养法分别进行培养。结果在3只真菌感染病兔中应用试管斜面法我们只检测到1例皮肤病原真菌阳性,而采用沙氏平皿法3例阳性全部检出。结论结合临床检测经验,我们认为本研究的沙氏平皿法优于沙氏试管斜面法,在实验动物皮肤病原真菌常规检测中具有推广应用价值。 相似文献
103.
Clinical Impact of Tumour Involvement of the Anastomotic Doughnut in Oesophagogastric Cancer Surgery
K Sillah EA Griffiths SA Pritchard R Swindell CM West R Page IM Welch 《Annals of the Royal College of Surgeons of England》2009,91(3):195-200
INTRODUCTION
Published colorectal cancer surgery data suggest no role for the analysis of the anastomotic doughnuts following anterior resection. The usefulness of routine histological analysis of the upper gastrointestinal doughnut is not clear. Our study assessed the impact of cancer involvement of the doughnut on clinical practice. Factors associated with doughnut involvement and the effect on patients'' survival were also analysed.PATIENTS AND METHODS
The clinicopathological details of 462 patients who underwent potentially curative oesophagogastrectomy for cancer with a stapled anastomosis between 1994 and 2006 in two specialist centres were retrospectively analysed. Univariate, multivariate and survival analyses were carried out.RESULTS
Approximately 5% of doughnuts (22 of 462) were histologically involved with cancer. Microscopic involvement of the proximal resection margin, local lymph node metastasis and lymphatic invasion within the main resected specimen were independently associated with doughnut involvement (all P < 0.05). However, these three factors taken together failed to predict doughnut involvement. Doughnut involvement was an independent adverse prognostic factor for overall survival (P = 0.0013).CONCLUSIONS
In contrast to findings in colorectal surgery, doughnut involvement with cancer appears to have useful prognostic information following oesophagogastrectomy. Routine histological analysis of upper gastrointestinal doughnuts is justified. Doughnut involvement could potentially strengthen the indications for adjuvant therapy in the future. 相似文献104.
V Venkatramani S Pillai S Marathe SA Rege JV Hardikar 《Annals of the Royal College of Surgeons of England》2009,91(5):W13-W14
Introduction
Breast gangrene has been reported as a complication following puerperal sepsis, breast surgery, nipple piercings, warfarin toxicity, etc. We report a case of primary breast gangrene in an HIV-positive individual which, to the best of our knowledge, is the first of its kind.Case report
A 40-year-old previously healthy woman presented with fulminating left breast gangrene. She was detected to be HIV positive. Mastectomy was performed. The detailed management of the condition is discussed.Conclusion
Severe necrotising infections may be initial manifestations of HIV infection and patients with such infections should be screened for HIV. 相似文献105.
Background
Within the last decade there has been a growth in the call-centre industry in the UK, with a growing awareness of the voice as an important tool for successful communication. Occupational voice problems such as occupational dysphonia, in a business which relies on healthy, effective voice as the primary professional communication tool, may threaten working ability and occupational health and safety of workers. While previous studies of telephone call-agents have reported a range of voice symptoms and functional vocal health problems, there have been no studies investigating the use and impact of vocal performance in the communication industry within the UK. This study aims to address a significant gap in the evidence-base of occupational health and safety research. The objectives of the study are: 1. to investigate the work context and vocal communication demands for call-agents; 2. to evaluate call-agents' vocal health, awareness and performance; and 3. to identify key risks and training needs for employees and employers within call-centres. 相似文献106.
107.
直视下尿道内切开术的再认识 总被引:7,自引:0,他引:7
目的:观察直视下尿道内切开术(DVIU)的长期疗效,重新评价DVIU的临床应用价值。方法:回顾性分析2003年1月~2007年1月收治的65例尿道狭窄或闭锁患者行DVIU及术后随访的临床资料:狭窄长度0.5~2.0cm,平均1.2cm。其中≤1.0cm者25例,1.1~2.0cm者40例。30例行尿道超声检查测量尿道瘢痕厚度,其中瘢痕厚度≤1cm者10例,〉1cm者20例,瘢痕长度和厚度均≤1cm者9例。结果:65例共行DVIU72例次,72例次内切开手术均获得成功。63例获得随访,随访时间24~60个月,平均40.5个月。48例(76.2%)因狭窄复发而最终接受开放手术。尿道超声显示瘢痕厚度≤1cm的10例中,只有1例接受手术;瘢痕厚度〉1cm的20例中,18例接受手术;瘢痕长度和厚度均≤1cm的9例均未行手术。结论:DVIU适合于狭窄段和瘢痕厚度均〈1cm的患者,切开次数以1次为宜,手术疗效与严格掌握适应证密切相关。 相似文献
108.
目的:探讨尿道狭窄患者围手术期尿液TGF-β1浓度变化情况以及影响该浓度的相关因素.方法:使用ELISA试剂盒对29例尿道狭窄患者术前1个月及术后1个月尿液中TGF-β1进行测定及记录.同期取泌尿系统其他手术的14例患者作为对照组,测定其术后1个月尿液中TGF-β1浓度.结果:检测结果显示实验组在接受手术治疗后尿液中TGF-β1含最较对照组有显著增高(P<0.05).同时实验组患者术前和术后尿液TGF-β1浓度也存在明显差异(P<0.05).在相关性因素的分析中,前尿道狭窄患者术后尿液中TGF-β1含量的变化幅度较后尿道狭窄患者更为显著(P<0.05),同时采用自体组织替代技术较传统端端吻合技术以及内镜切开技术更能引起尿液中TGF-β1的明显变化(P<0.05).但年龄、既往手术次数均未能引起患者术后TGF-β1的变化.结论:狭窄部位、手术方式都与患者尿液中 TGF-β1的含量存在一定的联系,而年龄及既往手术史等因素未发现与患者体内TGF-β1含量有较大的联系. 相似文献
109.
110.
目的 探讨马钱子碱抗肝细胞癌的作用及其机制.方法 体外培养人肝癌SMMC-7721细胞,加入不同浓度的马钱子碱(2.5~400μg/ml),细胞培养72 h,MTT法测定细胞生长抑制率.Western blotting和荧光定量RT-PCR技术分别测定培养24、48、72 h肝癌细胞PCNA、Cyclin D1、FAS基因mRNA和蛋白表达.结果 随着马钱子碱用量逐渐增加,对人肝癌细胞SMMC-7721生长抑制作用增强,马钱子碱用量为320 μg/ml时对肝癌细胞生长抑制率接近100%.马钱子碱作用肝癌细胞24 h与作用48 h相比,Fas蛋白和mRNA表达差异无统计学意义(分别F=2.547,1.582,均P>0.05),作用72 h时差异有统计学意义(分别F=1.036,1.137,均P<0.05);PCNA和Cyclin D1的mRNA和蛋白表达各时间点差异无统计学意义(PCNA分别F=3.612,2.174,3.029;Cyclin D1分别F=2.361,2.915,1.976,均P>0.05).结论 马钱子碱抑制肝癌细胞生长,可能通过肝癌细胞FAS基因和蛋白表达增加,诱导肝癌细胞凋亡发挥抑制作用,而与PCNA和Cyclin D1作用无关.Abstract: Objective To study the effect of brucine on the growth of a hepatocellular carcinoma cell line in vitro. Methods Brucine was added into a liver cancer cell line of SMMC-7721 in vitro, at drug concentration of brucine from 2. 5 μg/ml to 400 μg/ml. The inhibition rate of cell growth was measured by MTT technique after the cells were cultured for 72 hours. The protein and mRNA expression of PCNA,cyclin D1 and FAS were respectively assayed with Western blotting and fluorescent quantitation RT-PCR techniques at 24, 48, 72 h. Results The inhibition rate of liver cancer cell was near 100% when the brucine concentration was at 320 μg/ml. The protein and mRNA expression of FAS were of no significant difference at 24 h vs 48 h ( seperately F = 2. 547,1. 582, all P > 0. 05 ), and significant difference existed at 24 h vs 72 h( seperately F = 1. 036, 1. 137, all P < 0. 05 ). The protein and mRNA expression of PCNA,Cyclin D1 were of no significant difference between various time period( seperately PCNA F = 3.612,2. 174,3.029;Cyclin D1 F=2.361,2.915,1.976,all P>0.05). Conclusions Brucine inhibits the growth of liver cancer cells, by inducing increased apoptosis of the cells probably through FAS overexpression. 相似文献