首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   14184篇
  免费   673篇
  国内免费   483篇
耳鼻咽喉   15篇
儿科学   370篇
妇产科学   59篇
基础医学   1327篇
口腔科学   14篇
临床医学   1633篇
内科学   1048篇
皮肤病学   192篇
神经病学   84篇
特种医学   771篇
外科学   5172篇
综合类   1839篇
预防医学   549篇
眼科学   6篇
药学   916篇
  5篇
中国医学   1010篇
肿瘤学   330篇
  2023年   148篇
  2022年   332篇
  2021年   439篇
  2020年   436篇
  2019年   355篇
  2018年   399篇
  2017年   395篇
  2016年   429篇
  2015年   387篇
  2014年   833篇
  2013年   772篇
  2012年   809篇
  2011年   922篇
  2010年   818篇
  2009年   862篇
  2008年   750篇
  2007年   665篇
  2006年   687篇
  2005年   615篇
  2004年   526篇
  2003年   444篇
  2002年   368篇
  2001年   331篇
  2000年   351篇
  1999年   241篇
  1998年   237篇
  1997年   183篇
  1996年   189篇
  1995年   177篇
  1994年   159篇
  1993年   116篇
  1992年   131篇
  1991年   78篇
  1990年   71篇
  1989年   72篇
  1988年   70篇
  1987年   73篇
  1986年   48篇
  1985年   52篇
  1984年   37篇
  1983年   22篇
  1982年   36篇
  1981年   22篇
  1980年   33篇
  1979年   25篇
  1978年   24篇
  1977年   21篇
  1976年   24篇
  1974年   22篇
  1973年   23篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
IntroductionThere is no consensus on the most appropriate treatment for chronic active antibody-mediated rejection (cAMR). Recent studies suggest that treatment with tocilizumab (TCZ) may stabilize graft function, decrease the intensity of donor-specific HLA antibodies (DSAs) and reduce inflammation of microcirculation.Patients and methodsObservational study with renal allograft recipients diagnosed with cAMR (n = 5) who had not submitted a response to traditional treatment based on the combination of plasma replacements, immunoglobulins, and rituximab. Patients were told to be treated with TCZ as compassionate use in six doses per month (8 mg/kg/month). Renal function, proteinuria, and the intensity of DSAs were monitored during follow-up.ResultsFive patients, average age 60 ± 13 years, three male and two retrasplants (cPRA average 55%) with preformed DSAs. Treatment with TCZ was initiated within 47 ± 52 days of biopsy. In two cases treatment was discontinued after the first dose, by severe bicitopenia with cytomegalovirus viremia and by graft failure, respectively. In the three patients who completed treatment, no stability of renal function (serum creatinine from 1.73 ± 0.70 to 2.04 ± 0.52 mg/dL, e-FGR 4 6 ± 15 to 36 ± 16 mL/min), showed increased proteinuria (3.2 ± 4.0 to 6.9 ± 11.0 g/g) and the intensity of DSAs maintain stable. No changes were observed in the degree of inflammation of microcirculation (g + pt 4.2 ± 0.8 vs. 4.3 ± 1.0) or in the degree of transplant glomerulopathy (cg 1.2 ± 0.4 vs. 1.8 ± 1.0).ConclusionsTCZ therapy does not appear to be effective in modifying the natural history of chronic active antibody-mediated rejection, does not improve the degree of inflammation of microcirculation and does not reduces the intensity of DSAs.  相似文献   
2.
Oxidative stress and inflammation are two possible mechanisms related to nephrotoxicity caused by environmental pollutants. Ellagic acid, a powerful antioxidant phytochemical, may have great relevance in mitigating pollutant-induced nephrotoxicity and preventing the progression of kidney disease. This review discusses the latest findings on the protective effects of ellagic acid, its metabolic derivatives, the urolithins, against kidney toxicity caused by heavy metals, pesticides, mycotoxins, and organic air pollutants. We describe the chelating, antioxidant, anti-inflammatory, antifibrotic, antiautophagic, and antiapoptotic properties of ellagic acid to attenuate nephrotoxicity. Furthermore, we present the molecular targets and signaling pathways that are regulated by these antioxidants, and suggest some others that should be explored. Nevertheless, the number of reports is still limited to establish the efficacy of ellagic acid against kidney damage induced by environmental pollutants. Therefore, additional preclinical studies on this topic are required, as well as the development of well-designed clinical trials.  相似文献   
3.
4.
目的:探究翁连解毒汤治疗浊毒内蕴型溃疡性结肠炎(Ulcerative Colitis,UC)临床疗效及可能的作用机制。方法:选取2016年2月至2018年12月在攀枝花学院附属医院收治的浊毒内蕴型UC患者130例作为研究对象,按照入院先后顺序分为对照组和观察组,每组65例。对照组常规西医治疗,观察组加用翁连解毒汤,观察2组治疗前、完成治疗后T细胞、NK细胞、炎性反应因子、凝血功能、生命质量变化,完成治疗后总结疗效。结果:观察组患者在NK细胞、T淋巴细胞组成、CR、TNF-α、IL-1 β、ESR、内毒素、IL-10、FIB、PLT、APTT改善方面的效果较对照组更优,组间差异有统计学意义(P<0.05)。观察组患者完成治疗后的生命质量量表各维度评分及总评分改善效果优于对照组患者(P<0.05),且临床总有效率和组织病理学疗效率均高于对照组患者(P<0.05)。结论:翁连解毒汤能抑制浊毒内蕴型UC炎性反应,改善高凝状态,提高机体免疫功能,从而提高疗效和生命质量。  相似文献   
5.
Objective: To assess the effect of electroacupuncture(EA) on expression of cytoskeletal proteins from Sertoli cells(SCs) and spermatogenesis in rats with oligozoospermia of insufficiency of Shen(Kidney)essence syndrome(OIKES).Methods: Twenty healthy male Sprague-Dawley rats were randomly assigned to four groups using a random number table: control,tripterygium glycosides(TG) treatment,sham and EA groups(n=5 in each group).A rat model of OIKES was established by oral gavage with TG.The EA group was treated with TG and received EA at Shenshu(BL 23) and Zusanli(ST 36) acupoints for 20 min,once daily for 30 days,while the sham group received EA at identical acupoints with skin penetration without stimulation.After 30 days,the ?nal body weight and coef?cients for the testis and epididymis were calculated and sperm parameters were measured.Immunohistochemical analyses were performed to detect expression of vimentin and α-tubulin in SCs and proliferating cell nuclear antigen(PCNA) immunoreactivity in germ cells.Apoptosis in germ cells was quanti?ed by the transferase biotin-dUTP nick end labeling assay.Results: Compared with the control group,the final body weight and testis/epididymis coefficients of rats in the TG-treated group were not significantly different,but the sperm count and motility were lower(P0.05).Expressions of vimentin and α-tubulin were also signi?cantly weaker(P0.01).The PCNA immunoreactivity of germ cells was decreased(P=0.059),whereas the apoptotic index of germ cells was increased signi?cantly(P0.01).In contrast,EA at BL 23 and ST 36 acupoints signi?cantly improved the ?nal body weight as well as the sperm count,concentration and motility(P0.01 or P0.05).EA increased expression of vimentin and α-tubulin in SCs markedly,and signi?cantly enhanced PCNA immunoreactivity with decreased apoptosis in germ cells(P0.01 or P0.05).Conclusions: EA at BL 23 and ST 36 acupoints has protective effects on spermatogenesis in rats with OIKES.This effect seems to be achieved by attenuating TG-induced disruption of cytoskeletal protein in SCs.  相似文献   
6.
BackgroundData on adult sexual functioning after kidney transplantation (KTx) during childhood or adolescence are scarce.AimTo assess the long-term sexual and psychosocial quality of life after pediatric KTx.Methods29 young men (median age 27.1 years) were examined 18.7 years (median) after KTx. 56 age-matched healthy men (median age 30.0 years) served as controls.OutcomeWe studied the influence of sociodemographics, previous renal replacement therapy, current reproductive hormonal serum levels, testicular size, and data on several validated mental and physical questionnaires on participants' Derogatis Interview for Sexual Functioning self-report scores.ResultsThe KTx recipients had significantly poorer sexual functioning than their healthy peers. KTx men had less frequent sexual activity with a partner (P = .03) and poorer orgasms (P = .002) than the controls but no erectile dysfunction (P = .5).Clinical implicationsDepressive symptoms, relationship status, and longer dialysis duration predicted poor adult sexual functioning in KTx recipients, whereas age at transplantation or at the time of the study did not.Strengths & LimitationsThis study contributes extended follow-up data to the very scarce literature on adult sexual functioning in pediatric KTx recipients. Relatively small population and low participation rate limit the comprehensive data interpretation in a population-based cohort of male KTx recipients.ConclusionSexual functioning is often impaired in young men after pediatric KTx, emphasizing the need for long-term monitoring of sexual health and sexuality as important dimensions of quality of life.Tainio J, Jahnukainen T, Jalanko H, et al. Male Sexual Function After Pediatric Kidney Transplantation—A Cross-sectional Nationwide Study. J Sex Med 2020;17:2104–2107.  相似文献   
7.
陈玉琴 《中外医疗》2016,(26):169-171
目的:探讨分析补肾纳气法治疗小儿支气管哮喘的临床效果。方法方便选取该院儿科于2013年3月—2014年11月收治的小儿支气管哮喘患者67例,根据随机数字法分为对照组33例和观察组34例,对照组患者予以氨茶碱片治疗,观察组患者实施补肾纳气法治疗,观察两组患者的治疗效果,进行临床对照性分析。结果对照组患者不良反应发生率24.2%,观察组患者不良反应发生率5.8%,观察组不良反应发生率明显低于对照组(P﹤0.05);对照组患者总有效率60.6%,观察组患者总有效率85.3%。观察组患者治疗后总有效率明显高于对照组(P﹤0.05)。结论补肾纳气法治疗小儿支气管哮喘的临床效果好,应用价值高,值得在临床实践中推广应用。  相似文献   
8.
慢性肾脏病是一种以肾脏功能的损伤为主要表现,并可累及全身多脏器的慢性进展性疾病。中医辨证治疗本病在延缓病情、改善预后等方面具有显著的优势。通过中医理论研究及临床经验总结,笔者提出从“肾毒”论治慢性肾脏病,认为其不仅是本病的致病因素,更是重要的病理产物,是本病发生发展、迁延难愈的关键。在治疗上提出以“益肾元、解肾毒”为大法,并根据不同兼夹辨证施治,采用药对,长治缓图。以“肾毒”立论拟定的经验方苏茵解毒方,在临床治疗和实验研究上均显示出明显的效果,并已制备成院内制剂临床使用,在疗效及经济效益方面均具有显著的优势。  相似文献   
9.

Background

Patients undergoing cardiac surgery are at significant risk of developing postoperative acute kidney injury (AKI). Neutrophil–lymphocyte ratio (NLR) is a widely available inflammatory biomarker which may be of prognostic value in this setting.

Methods

We conducted a systematic review and meta-analysis of studies reporting associations between perioperative NLR with postoperative AKI. We searched Medline, Embase and the Cochrane Library, without language restriction, from inception to May 2022 for relevant studies. We meta-analysed the reported odds ratios (ORs) with 95% confidence intervals (CIs) for both elevated preoperative and postoperative NLR with risk of postoperative AKI and need for renal replacement therapy (RRT). We conducted a meta-regression to explore inter-study statistical heterogeneity.

Results

Twelve studies involving 10,724 participants undergoing cardiac surgery were included, with eight studies being deemed at high risk of bias using PROBAST modelling. We found statistically significant associations between elevated preoperative NLR and postoperative AKI (OR 1.45, 95% CI 1.18–1.77), as well as postoperative need for RRT (OR 2.37, 95% CI 1.50–3.72). Postoperative NLR measurements were not of prognostic significance.

Conclusions

Elevated preoperative NLR is a reliable inflammatory biomarker for predicting AKI following cardiac surgery.  相似文献   
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号