全文获取类型
收费全文 | 174588篇 |
免费 | 14389篇 |
国内免费 | 4888篇 |
专业分类
耳鼻咽喉 | 1108篇 |
儿科学 | 3138篇 |
妇产科学 | 1780篇 |
基础医学 | 26813篇 |
口腔科学 | 3431篇 |
临床医学 | 16926篇 |
内科学 | 25759篇 |
皮肤病学 | 2031篇 |
神经病学 | 7841篇 |
特种医学 | 3297篇 |
外国民族医学 | 24篇 |
外科学 | 13681篇 |
综合类 | 26059篇 |
现状与发展 | 13篇 |
一般理论 | 33篇 |
预防医学 | 16807篇 |
眼科学 | 4307篇 |
药学 | 17884篇 |
16篇 | |
中国医学 | 8234篇 |
肿瘤学 | 14683篇 |
出版年
2024年 | 127篇 |
2023年 | 2018篇 |
2022年 | 2892篇 |
2021年 | 5530篇 |
2020年 | 5453篇 |
2019年 | 5739篇 |
2018年 | 5688篇 |
2017年 | 5652篇 |
2016年 | 5862篇 |
2015年 | 5823篇 |
2014年 | 9199篇 |
2013年 | 11377篇 |
2012年 | 8670篇 |
2011年 | 10069篇 |
2010年 | 8699篇 |
2009年 | 8529篇 |
2008年 | 8468篇 |
2007年 | 9558篇 |
2006年 | 8849篇 |
2005年 | 8487篇 |
2004年 | 7444篇 |
2003年 | 6617篇 |
2002年 | 4923篇 |
2001年 | 4858篇 |
2000年 | 3954篇 |
1999年 | 3620篇 |
1998年 | 2485篇 |
1997年 | 2285篇 |
1996年 | 2311篇 |
1995年 | 2308篇 |
1994年 | 2055篇 |
1993年 | 1904篇 |
1992年 | 1643篇 |
1991年 | 1448篇 |
1990年 | 1188篇 |
1989年 | 1144篇 |
1988年 | 1031篇 |
1987年 | 784篇 |
1986年 | 579篇 |
1985年 | 641篇 |
1984年 | 659篇 |
1983年 | 398篇 |
1982年 | 491篇 |
1981年 | 417篇 |
1980年 | 361篇 |
1979年 | 301篇 |
1978年 | 247篇 |
1977年 | 202篇 |
1976年 | 237篇 |
1975年 | 149篇 |
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
61.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2022,32(2):469-478
Background and aimsThe relationship between hemoglobin glycation index (HGI) and the diagnosis and prognosis of cardiovascular disease (CVD) has been verified by previous studies. However, it remains unknown whether HGI has a predictive effect on subclinical myocardial injury (SC–MI). The purpose of the present study was to explore the relationship between HGI and SC–MI in the general population free from CVD.Methods and resultsThe present study included 6009 participants free of CVD from the third National Health and Nutrition Examination Survey. Binary Logistic regression analysis was used to tested the association between HGI and SC–MI. As results, the HGI was significantly higher in participants with SC–MI compared with those without, and the HGI was positively correlated with SC–MI and other metabolic disorder parameters. Each 1-unit increase of HGI and glycated hemoglobin A1c (HbA1c) was independently associated with higher risk of SC–MI (P < 0.05), while fasting plasma glucose (FPG) was no longer a predictive indicator of SC–MI with the increase of confounding factors [OR (95% CI): 1.001 (0.999–1.003), P = 0.305]. And in the subgroup analysis, HGI, only in participants without diabetes, was independently associated with higher risk of SC–MI, while HbA1c and FPG had no independent predictive role in both diabetic and non-diabetic participants.ConclusionsHGI was a significant predictor of SC–MI in the general population free from CVD. 相似文献
62.
背景 结核性脑膜炎(TM)是临床常见的中枢性感染的一种,其起病较慢,症状不典型,病原学诊断困难,误诊率高。目前有效的TM诊断工具较少。利用常见的临床症状、检查指标等建立诊断评分系体可提高诊断准确率,减少误诊。 目的 建立TM临床诊断评分体系(TMCDS),并对其应用价值进行初步评价。 方法 选取2011年11月至2021年9月在柳州市人民医院感染病科住院并诊断为脑膜炎的患者187例为研究对象,采用SPSS 21.0统计软件将患者随机分成建模组(147例)和验模组(40例)。根据是否为TM将建模组分为非TM亚组(76例)和TM亚组(71例)。收集患者的一般资料,主要包括性别、年龄、临床症状(发热、头痛、意识障碍、颈抵抗),实验室及影像学检查结果,包括人类免疫缺陷病毒(HIV)感染情况、CD4+ T淋巴细胞计数、C反应蛋白、颅内压、脑脊液常规生化检查(糖、氯、蛋白、细胞数)。建模组采用多因素Logistic回归分析探讨TM的影响因素;根据每个因素的β值所占比重设立相应分值,建立TMCDS;采用受试者工作特征曲线(ROC曲线)分析TMCDS诊断TM的价值。 结果 两亚组头痛、HIV感染、CD4+ T淋巴细胞计数<200/μl、C反应蛋白升高、颅内压>200 mm H2O(1 mm H2O=0.009 8 kPa)、脑脊液糖降低、脑脊液氯降低、脑脊液蛋白升高、脑脊液单核细胞升高情况比较,差异有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,头痛、CD4+ T淋巴细胞<200/μl、C反应蛋白升高、脑脊液糖降低、脑脊液蛋白升高均是TM的影响因素(P<0.05)。将以上5个影响因素同时结合临床经验纳入脑脊液氯、脑脊液细胞数再次进行多因素Logistic回归分析,结果显示,头痛、CD4+ T淋巴细胞<200/μl、C反应蛋白升高、脑脊液糖降低、脑脊液蛋白升高均是TM的影响因素(P<0.05)。根据上述7个因素β值建立评分系统,将脑脊液氯降低β值设定为1分,其他因素β值与其的倍数即为该因素所对应的分值,因2个影响因素评分为负值,为方便临床,每个因素对应分值增加2.5分,最终建立TMCDS。TMCDS诊断建模组TM的ROC曲线下面积(AUC)为0.807〔95%CI(0.735,0.879),标准误=0.037,P<0.001〕,最佳诊断界值为21.50分。TMCDS诊断验模组TM的AUC为0.766〔95%CI(0.610,0.921),标准误=0.079,P=0.004〕,灵敏度为0.789,特异度为0.667。 结论 通过7个变量建立的TMCDS简单易行,对于早期TM具有较高的临床诊断价值。 相似文献
63.
目的研究异牡荆素(ISO)对非小细胞性肺癌(NSCLC)细胞的影响和潜在的机制。方法将A549和H1650细胞分别分为空白组、低剂量实验组(4μmol·L-1 ISO)和高剂量实验组(16μmol·L-1 ISO)。用噻唑蓝法检测NSCLC细胞活性,用肿瘤球形成实验检测NSCLC细胞的细胞球形成率,用Western blot法检测NSCLC细胞凋亡、自我更新、无翅型MMTV整合位点家族/β-连环蛋白(Wnt/β-catenin)信号通路相关蛋白的表达水平。结果与空白组比较,低、高剂量实验组中A549和H1650细胞在24,48和72 h的细胞活性均显著降低。低、高剂量实验组和空白组中A549细胞的细胞球形成率分别为(4.18±0.45)%,(2.01±0.67)%和(6.02±0.57)%,切割的半胱氨酸蛋白酶-3相对表达量分别为0.24±0.08,1.25±0.13和0.06±0.07,SRY相关高迁移率族盒蛋白-2相对表达量分别为0.49±0.04,0.25±0.03和1.00±0.09,Kruppel样因子4相对表达量分别为0.68±0.04,0.44±0.03和1.01±0.06,Wnt1相对表达量分别为0.63±0.06,0.28±0.04和1.00±0.06,β-catenin相对表达量分别为0.41±0.05,0.22±0.03和1.01±0.09;与空白组比较,低、高剂量实验组中A549细胞的上述指标的差异均有统计学意义(P<0.05,P<0.01)。上述3组中H1650细胞的上述指标也呈现一致的现象。结论ISO可能通过抑制Wnt/β-catenin信号通路来抑制NSCLC细胞活性和自我更新,并促进其凋亡。 相似文献
64.
Co-trimoxazole is mainly used as a first-line drug for treatment and prophylaxis against Pneumocystis jiroveci pneumonia. This drug, however, has been reported as the most common causative drug for severe cutaneous adverse reactions (SCARs). This study aimed to extensively elucidate the associations between genetic polymorphisms of HLA class I and genes involved in bioactivation and detoxification of co-trimoxazole on co-trimoxazole-induced SCARS in a large sample size and well-defined Thai SCARs patients. A total of 67 patients with co-trimoxazole-induced SCARs, consisting of 51 SJS/TEN patients and 16 DRESS patients, and 91 co-trimoxazole tolerant controls were enrolled in the study. The results clearly demonstrated that the HLA-B113:01 allele was significantly associated with co-trimoxazole-induced SCARs, especially with DRESS (OR = 8.44, 95% CI = 2.66–26.77, P = 2.94 × 10−4, Pc = 0.0126). Moreover, the HLA-C108:01 allele was significantly associated with co-trimoxazole-induced SJS/TEN in the HIV/AIDS patients with an OR of 8.51 (95% CI = 2.18–33.14, P = 8.60 × 10−4, Pc = 0.0241). None of the genes involved in the bioactivation and detoxification of co-trimoxazole investigated in this study play any major role in the development of all phenotypes of SCARs. 相似文献
65.
66.
目的研究生慧汤对APP/PS1(β-amyloid precursor protein/presenilin 1246E)小鼠海马内β淀粉样前体蛋白(Amyloid precursor protein,APP)代谢产物昼夜表达的影响。方法 将56只雄性APP/PS1双转基因痴呆模型小鼠随机分为4组,分别为:痴呆模型组、褪黑素治疗组(0.78 mg·kg-1·d-1)、生慧汤高剂量组(27.0 g·kg-1·d-1)、生慧汤低剂量组(13.5 g·kg-1·d-1),每组14只;对照组为14只雄性C57BL/6J小鼠,连续给药30天。采用Morris水迷宫检测小鼠学习记忆能力,采用酶联免疫吸附检测(ELISA)检测不同时间段取出的海马组织sAPPα含量。对海马β淀粉样蛋白1-40、β淀粉样蛋白1-42表达进行免疫印迹分析。免疫组化(IHC)检测海马CA1区Aβ1-40蛋白的表达。结果 Morris水迷宫结果表明,与对照组相比,模型组上平台潜伏期明显延长、穿越平台次数明显减少(P<0.01);与模型组相比,生慧汤不同剂量组上平台潜伏期明显缩短(P<0.01、P<0.05),穿越平台次数明显增加(P<0.05)。ELISA结果表明,与对照组相比,模型组的sAPPα总量、各时间段(12:00、24:00)sAPPα含量明显减少(P<0.01);与模型组相比,生慧汤不同剂量组sAPPα总量明显增多(P<0.01、P<0.05),生慧汤高剂量组仅能增加12:00 sAPPα含量(P<0.01),生慧汤低剂量组仅能增加24:00 sAPPα含量(P<0.05)。对照组sAPPα含量具有明显昼夜差异(P<0.01)。模型组sAPPα含量的昼夜差异性消失(P>0.05)。生慧汤高剂量组sAPPα含量具有昼夜差异(P<0.01),生慧汤低剂量组sAPPα含量不具有昼夜差异(P>0.05)。Western blot结果显示,与对照组相比,模型组Aβ1-40、Aβ1-42蛋白表达明显增加(P<0.01);与模型组相比,生慧汤高剂量组Aβ1-40、Aβ1-42蛋白表达减少(P<0.05、P<0.01);生慧汤低剂量组仅能减少Aβ1-40蛋白的表达(P<0.05),对Aβ1-42蛋白表达无影响(P>0.05)。免疫组化结果表明,与对照组相比,模型组Aβ1-40表达明显增加(P<0.01);与模型组相比,生慧汤不同剂量组Aβ1-40表达不同程度减少(P<0.01、P<0.05)。结论 生慧汤能够改善5月龄APP/PS1阿尔茨海默病模型小鼠的学习记忆障碍,其机制可能与恢复海马内APP代谢产物sAPPα的昼夜节律性表达、从而减少Aβ的沉积有关。 相似文献
67.
《Taiwanese journal of obstetrics & gynecology》2022,61(6):1082-1085
ObjectiveWe report a low-grade endometrial stromal sarcoma (ESS) with a novel CDKN1A-JAZF1 fusion gene arising from abdominal wall endometrioma.Case reportA 40-year-old woman presented with a 5.5-cm abdominal wall mass juxtaposed to the postoperative scar of two cesarean sections. Histologically, the tumor exhibited obvious tongue-like protrusions into the surrounding tissue, showed spindle cells with multinodular growth pattern that occasionally rotate around small arteries. Immunohistochemically, the tumor cells were positive for CD10, estrogen receptor (ER), progesterone receptor (PR), negatively stained for smooth muscle actin (SMA), CD117, CyclinD1. In addition, a previously undescribed gene fusion between CDNK1A 5′ end of exon 1(NM_000389.5) and JAZF1 3′ end of exon 5 (NM_175,061,3) was reported in this case.ConclusionThis report of ESS suggesting that rapidly growing abdominal wall masses without menstruation-related should be promptly evaluated and treated aggressively. In addition, we have expanded the molecular landscape of low-grade ESS. 相似文献
68.
69.
Loren Saulsberry PhD Ankur Bhargava MD MPH Sharon Zeng BA Jason B. Gibbons PhD Cody Brannan MS Diane S. Lauderdale PhD Robert D. Gibbons PhD 《Health services research》2023,58(4):873-881
Objective
To derive and validate a new ecological measure of the social determinants of health (SDoH), calculable at the zip code or county level.Data Sources and Study Setting
The most recent releases of secondary, publicly available data were collected from national U.S. health agencies as well as state and city public health departments.Study Design
The Social Vulnerability Metric (SVM) was constructed from U.S. zip-code level measures (2018) from survey data using multidimensional Item Response Theory and validated using outcomes including all-cause mortality (2016), COVID-19 vaccination (2021), and emergency department visits for asthma (2018). The SVM was also compared with the existing Centers for Disease Control and Prevention's Social Vulnerability Index (SVI) to determine convergent validity and differential predictive validity.Data Collection/Extraction Methods
The data were collected directly from published files available to the public online from national U.S. health agencies as well as state and city public health departments.Principal Findings
The correlation between SVM scores and national age-adjusted county all-cause mortality was r = 0.68. This correlation demonstrated the SVM's robust validity and outperformed the SVI with an almost four-fold increase in explained variance (46% vs. 12%). The SVM was also highly correlated (r ≥ 0.60) to zip-code level health outcomes for the state of California and city of Chicago.Conclusions
The SVM offers a measurement tool improving upon the performance of existing SDoH composite measures and has broad applicability to public health that may help in directing future policies and interventions. The SVM provides a single measure of SDoH that better quantifies associations with health outcomes. 相似文献70.