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   21453篇
  免费   1220篇
  国内免费   612篇
耳鼻咽喉   166篇
儿科学   343篇
妇产科学   89篇
基础医学   2629篇
口腔科学   874篇
临床医学   1834篇
内科学   2305篇
皮肤病学   170篇
神经病学   922篇
特种医学   371篇
外科学   2123篇
综合类   3157篇
预防医学   1204篇
眼科学   205篇
药学   5544篇
  17篇
中国医学   882篇
肿瘤学   450篇
  2023年   204篇
  2022年   325篇
  2021年   603篇
  2020年   541篇
  2019年   493篇
  2018年   525篇
  2017年   526篇
  2016年   552篇
  2015年   544篇
  2014年   1383篇
  2013年   1448篇
  2012年   1346篇
  2011年   1419篇
  2010年   1147篇
  2009年   1119篇
  2008年   1003篇
  2007年   1019篇
  2006年   940篇
  2005年   916篇
  2004年   753篇
  2003年   594篇
  2002年   546篇
  2001年   454篇
  2000年   379篇
  1999年   392篇
  1998年   310篇
  1997年   288篇
  1996年   248篇
  1995年   243篇
  1994年   241篇
  1993年   170篇
  1992年   215篇
  1991年   168篇
  1990年   180篇
  1989年   167篇
  1988年   149篇
  1987年   130篇
  1986年   107篇
  1985年   222篇
  1984年   200篇
  1983年   149篇
  1982年   171篇
  1981年   132篇
  1980年   110篇
  1979年   110篇
  1978年   64篇
  1977年   55篇
  1976年   55篇
  1975年   37篇
  1973年   57篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Anthrax is a zoonotic infection caused by the gram-positive, aerobic, spore-forming bacterium Bacillus anthracis. Depending on the origin of the infection, serious health problems or mortality is possible. The virulence of B. anthracis is reliant on three pathogenic factors, which are secreted upon infection: protective antigen (PA), lethal factor (LF), and edema factor (EF). Systemic illness results from LF and EF entering cells through the formation of a complex with the heptameric form of PA, bound to the membrane of infected cells through its receptor. The currently available anthrax vaccines have multiple drawbacks, and recombinant PA is considered a promising second-generation vaccine candidate. However, the inherent chemical instability of PA through Asn deamidation at multiple sites prevents its use after long-term storage owing to loss of potency. Moreover, there is a distinct possibility of B. anthracis being used as a bioweapon; thus, the developed vaccine should remain efficacious and stable over the long-term. Second-generation anthrax vaccines with appropriate adjuvant formulations for enhanced immunogenicity and safety are desired. In this article, using protein engineering approaches, we have reviewed the stabilization of anthrax vaccine candidates that are currently licensed or under preclinical and clinical trials. We have also proposed a formulation to enhance recombinant PA vaccine potency via adjuvant formulation.  相似文献   
2.
目的 探讨聚焦解决护理模式结合健康教育对银屑病患者心理状态、应对方式的影响。方法 选取2020年2月至2021年2月我院收治的100例银屑病患者,随机分为观察组(聚焦解决护理模式结合健康教育)与对照组(常规健康教育)。比较两组的心理状态及应对方式。结果 干预后,观察组的焦虑自评量表(SAS)、抑郁自评量表(SDS)评分低于对照组(P<0.05)。干预后,观察组的面对评分高于对照组,屈服、回避评分低于对照组(P<0.05)。干预后,观察组的病耻感评分低于对照组(P<0.05)。结论 聚焦解决护理模式结合健康教育可有效改善银屑病患者的不良情绪,减轻病耻感,转变疾病应对方式。  相似文献   
3.
《药学学报(英文版)》2020,10(5):799-811
Overexpression of adenosine triphosphate (ATP)-binding cassette subfamily G member 2 (ABCG2) in cancer cells is known to cause multidrug resistance (MDR), which severely limits the clinical efficacy of chemotherapy. Currently, there is no FDA-approved MDR modulator for clinical use. In this study, rociletinib (CO-1686), a mutant-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), was found to significantly improve the efficacy of ABCG2 substrate chemotherapeutic agents in the transporter-overexpressing cancer cells in vitro and in MDR tumor xenografts in nude mice, without incurring additional toxicity. Mechanistic studies revealed that in ABCG2-overexpressing cancer cells, rociletinib inhibited ABCG2-mediated drug efflux and increased intracellular accumulation of ABCG2 probe substrates. Moreover, rociletinib, inhibited the ATPase activity, and competed with [125I] iodoarylazidoprazosin (IAAP) photolabeling of ABCG2. However, ABCG2 expression at mRNA and protein levels was not altered in the ABCG2-overexpressing cells after treatment with rociletinib. In addition, rociletinib did not inhibit EGFR downstream signaling and phosphorylation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). Our results collectively showed that rociletinib reversed ABCG2-mediated MDR by inhibiting ABCG2 efflux function, thus increasing the cellular accumulation of the transporter substrate anticancer drugs. The findings advocated the combination use of rociletinib and other chemotherapeutic drugs in cancer patients with ABCG2-overexpressing MDR tumors.  相似文献   
4.
Macrophages are the most abundant immune cells in the lung, which play an important role in COPD. The anti-inflammatory and anti-oxidation of ergosterol are well documented. However, the effect of ergosterol on macrophage polarization has not been studied. The objective of this work was to investigate the effect of ergosterol on macrophage polarization in CSE-induced RAW264.7 cells and Sprague-Dawley (SD) rats COPD model. Our results demonstrate that CSE-induced macrophages tend to the M1 polarization via increasing ROS, IL-6 and TNF-α, as well as increasing MMP-9 to destroy the lung construction in both RAW264.7 cells and SD rats. However, treatment of RAW264.7 cells and SD rats with ergosterol inhibited CSE-induced inflammatory by decreasing ROS, IL-6 and TNF-α, and increasing IL-10 and TGF-β, shuffling the dynamic polarization of macrophages from M1 to M2 both in vitro and in vivo. Ergosterol also decreased the expression of M1 marker CD40, while increased that of M2 marker CD163. Moreover, ergosterol improved the lung characters in rats by decreasing MMP-9. Furthermore, ergosterol elevated HDAC3 activation and suppressed P300/CBP and PCAF activation as well as acetyl NF-κB/p65 and IKKβ, demonstrating that HDAC3 deacetylation was involved in the effect of ergosterol on macrophage polarization. These results also provide a proof in immunoregulation of ergosterol for therapeutic effects of cultured C. sinensis on COPD patients.  相似文献   
5.
《中国现代医生》2020,58(21):110-112
目的 探讨中药肠道灌洗联合血液净化治疗急性农药中毒的临床疗效。方法 选取2014年4月~2019年10月本院收治的50例急性农药中毒患者为研究对象,并根据不同的治疗方案将患者分为对照组与观察组,各25例,对照组采用常规治疗联合血液净化治疗,而观察组在对照组的基础上采用中药肠道灌洗治疗,比较两组患者的临床疗效及血压、血气指标情况。结果 治疗后,观察组的临床总有效率为96.00%,对照组为76.00%,两组比较,观察组明显高于对照组;同时观察组的收缩压(SBP)、舒张压(DBP)与酸碱度(pH)高于对照组,动脉血氧分压(PaO2)与动脉血二氧化碳分压(PaCO2)低于对照组,组间比较差异有统计学意义(P0.05)。结论 对急性农药中毒患者实施中药肠道灌洗联合血液净化治疗,能有效改善患者的血压、血气指标,具有显著的临床疗效。  相似文献   
6.
《中国现代医生》2020,58(6):165-168
[摘要]目的探讨问题导向学习(PBL)结合绘图教学模式在临床护理带教中的应用效果。方法纳入2016年6月~2017年6月在我院实习的本科护生78名,按等比例随机分为观察组和対照组,观察组采取PBL结合绘图学模式法,对照组采用单纯PBL教学模式,利用统计学方法按照参考指标对两组实习生的考核数据进行对比分。结果观察组理论知识得分明显大于对照组[(90.31±4.55)分vs.(81.30±5.69)分],观察组临床实践技能得分明显大于对照组[(92.21±4.18)分vs.(80.31±5.39)分],差异均有统计学意义(P0.05)。结论PBL结合绘图教学模式临床护理带教中效果显著,比单纯PBL教学模式更具有优势,更有利于培养学生的循证思维与创新能力,提高临护理教学质量,在临床护理带教中值得推广。  相似文献   
7.
目的:探讨胃癌患者根治术后腹腔冲洗液中CEA mRNA表达情况及其临床意义。方法: 回顾性分析了2013 年1 月至2017 年12 月在南京大学医学院附属鼓楼医院接受胃癌根治切除术后进行腹腔灌洗液CEA mRNA检测的139 名患者的病历资料,并进行术后常规随访。用RT-PCR检测139 胃癌患者根治术后腹腔灌洗液中CEA mRNA表达情况。卡方检验分析腹腔灌洗液中CEA mRNA表达与临床基本特征、组织病理学资料、血液学指标及复发方式之间的关系。采用Logistic 单因素及多因素回归分析筛查影响CEA mRNA表达水平的因素。结果:139 名患者中44 名(31.7%)患者腹腔灌洗液CEA mRNA阳性。分析显示,胃癌患者腹腔灌洗液CEA mRNA阳性表达与性别、年龄、病理分级、Lauren 分型和HER2、EGFR、VEGFR等标记物间均没有明显的关联(均P>0.05),与病理类型、脉管是否侵犯、局部浸润深度、淋巴结转移程度和临床AJCC 分期有明显的关联(均P<0.05)。CEA mRNA阳性患者腹膜复发率明显高于阴性患者(P=0.012)。Logistic 单因素回归分析显示,印戒细胞癌(P=0.04,HR=2.810,95% CI: 1.050~7.520)、T 分期(P=0.016,HR=6.329,95% CI: 1.417~28.264)、N 分期(P=0.022,HR=3.068,95% CI: 1.172~8.027)、AJCC分期(P=0.016 ,HR=3.971 ,95% CI: 1.295~12.173 )、神经侵犯(P=0.002 ,HR=6.738,95% CI: 1.995~22.757)、脉管侵犯(P<0.001,HR=16.36,95% CI: 3.85~69.512)为胃癌患者腹腔灌洗液CEA mRNA阳性表达的危险因素。Logistic 多因素回归分析显示,经过对其他因素的校正,脉管侵犯(P<0.001,HR=21.314,95% CI: 4.21~107.907)为胃癌患者腹腔灌洗液CEA mRNA阳性表达的独立危险因素。结论:胃癌腹腔灌洗CEA mRNA阳性的患者腹膜复发转移风险高且预后不良,应考虑包括腹腔局部治疗在内的更加积极的抗肿瘤治疗。  相似文献   
8.
《Clinical therapeutics》2019,41(10):2066-2072.e2
PurposeAortic stenosis is a common cause of valvular heart disease with no means of prevention. The recognized association between aortic stenosis and serum phosphate raises the possibility of preventing progression of the disorder by using phosphate-binding drugs, but there is uncertainty whether such treatment lowers serum phosphate levels in patients without diagnosed renal failure. This pilot study was conducted to answer this question in patients with aortic stenosis.MethodsA randomized, double-blind, crossover trial of the phosphate-binding drug sevelamer was conducted in 72 patients. Patients were prescribed sevelamer 0.8 g (low-dose), sevelamer 2.4 g (high-dose), and matching placebo, 3 times daily with food; each regimen lasted 6 weeks and was allocated at random. Serum phosphate levels were measured at the end of each treatment period, and within-person levels were compared.FindingsSixty-one patients completed the 3 treatment periods. There was no significant difference in the mean end-treatment phosphate levels across all patients (3.38, 3.36, and 3.31 mg/dL with placebo, low-dose sevelamer, and high-dose sevelamer, respectively). Post hoc analysis showed a reduction in phosphate levels with increasing sevelamer dose in the highest baseline phosphate quartile group; a 0.3 mg/dL reduction (mean, 4.09 mg/dL with placebo, 3.95 mg/dL with low-dose sevelamer, and 3.79 mg/dL with high-dose sevelamer; Ptrend = 0.027).ImplicationsSevelamer had no overall statistically significant effect in lowering serum phosphate levels, but a reduction was observed in patients with phosphate levels in the highest quartile group of the population distribution. This hypothesis-generating result requires confirmation in an independent study. If confirmed, a trial of sevelamer in preventing the progression of aortic stenosis may be justified in patients with high phosphate levels. ISRCTN Registry identifier: ISRCTN17365679.  相似文献   
9.
10.
目的:观察中药灌洗负压治疗糖足创面的临床疗效。方法:将60例糖尿病足住院患者随机分为观察组30例和对照组30例。观察组给予常规基础及中药灌洗负压技术治疗,对照组给予常规基础及盐水灌洗负压治疗,疗程为21 d,观察两组患者全血白细胞计数、C反应蛋白、创面面积变化、创面缩小率、换药次数及创面局部各症状积分的变化情况。结果:近期疗效结果表明观察组总有效率96.67%,明显高于对照组的90%(P0.05)。两组患者创面局部各症状积分治疗前后对比,差异有统计学意义(P0.05)。治疗后,观察组WBC、CRP、创面面积及换药次数等观察指标分别为(5.86±1.37)×109/L、(4.59±1.10) mg/L、(5.81±2.01) cm~2、(5.33±0.92)次,均明显低于对照组,治疗后创面缩小率(25.06±5.91)%明显高于对照组。结论:临床上应用中药灌洗负压技术治疗糖尿病足创面,可以明显缩短创面愈合时间,提高愈合率,减少换药次数,减轻患者换药痛苦和医护人员工作量。在治疗上具有自己的特色和优势,值得临床进一步推广应用。  相似文献   
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