全文获取类型
收费全文 | 13626篇 |
免费 | 771篇 |
国内免费 | 673篇 |
专业分类
耳鼻咽喉 | 340篇 |
儿科学 | 850篇 |
妇产科学 | 55篇 |
基础医学 | 590篇 |
口腔科学 | 47篇 |
临床医学 | 1128篇 |
内科学 | 4155篇 |
皮肤病学 | 12篇 |
神经病学 | 302篇 |
特种医学 | 325篇 |
外国民族医学 | 1篇 |
外科学 | 3001篇 |
综合类 | 1883篇 |
现状与发展 | 4篇 |
预防医学 | 337篇 |
眼科学 | 15篇 |
药学 | 1074篇 |
4篇 | |
中国医学 | 668篇 |
肿瘤学 | 279篇 |
出版年
2024年 | 20篇 |
2023年 | 207篇 |
2022年 | 321篇 |
2021年 | 428篇 |
2020年 | 440篇 |
2019年 | 345篇 |
2018年 | 393篇 |
2017年 | 373篇 |
2016年 | 438篇 |
2015年 | 400篇 |
2014年 | 856篇 |
2013年 | 997篇 |
2012年 | 687篇 |
2011年 | 721篇 |
2010年 | 682篇 |
2009年 | 689篇 |
2008年 | 737篇 |
2007年 | 720篇 |
2006年 | 676篇 |
2005年 | 637篇 |
2004年 | 490篇 |
2003年 | 441篇 |
2002年 | 424篇 |
2001年 | 349篇 |
2000年 | 289篇 |
1999年 | 241篇 |
1998年 | 238篇 |
1997年 | 209篇 |
1996年 | 202篇 |
1995年 | 162篇 |
1994年 | 189篇 |
1993年 | 137篇 |
1992年 | 110篇 |
1991年 | 105篇 |
1990年 | 109篇 |
1989年 | 74篇 |
1988年 | 90篇 |
1987年 | 54篇 |
1986年 | 46篇 |
1985年 | 38篇 |
1984年 | 47篇 |
1983年 | 27篇 |
1982年 | 38篇 |
1981年 | 29篇 |
1980年 | 30篇 |
1979年 | 24篇 |
1977年 | 23篇 |
1976年 | 15篇 |
1975年 | 17篇 |
1974年 | 16篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Weina Cheng Yazhi Wang Jingxian Liu Xiaofei Li Ming Yu Cancan Duan Liu Liu Jianyong Zhang 《Journal of applied toxicology : JAT》2022,42(6):970-980
Cantharidin (CTD) is an effective antitumor agent. However, it exhibits significant hepatotoxicity, the mechanism of which remains unclear. In this study, biochemical and histopathological analyses complemented with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS)-based targeted metabolomic analysis of bile acids (BAs) were employed to investigate CTD-induced hepatotoxicity in rats. Sixteen male and female Sprague–Dawley rats were randomly divided into two groups: control and CTD (1.0 mg/kg) groups. Serum and liver samples were collected after 28 days of intervention. Biochemical, histopathological, and BA metabolomic analyses were performed for all samples. Further, the key biomarkers of CTD-induced hepatotoxicity were identified via multivariate and metabolic pathway analyses. In addition, metabolite–gene–enzyme network and Kyoto Encyclopedia of Genes and Genomes pathway analyses were used to identify the signaling pathways related to CTD-induced hepatotoxicity. The results revealed significantly increased levels of biochemical indices (alanine aminotransferase, aspartate aminotransferase, and total bile acid). Histopathological analysis revealed that the hepatocytes were damaged. Further, 20 endogenous BAs were quantitated via UHPLC-MS/MS, and multivariate and metabolic pathway analyses of BAs revealed that hyocholic acid, cholic acid, and chenodeoxycholic acid were the key biomarkers of CTD-induced hepatotoxicity. Meanwhile, primary and secondary BA biosynthesis and taurine and hypotaurine metabolism were found to be associated with the mechanism by which CTD induced hepatotoxicity in rats. This study provides useful insights for research on the mechanism of CTD-induced hepatotoxicity. 相似文献
2.
《European journal of surgical oncology》2022,48(3):482-491
ObjectiveTo systematically evaluate the clinicopathological and prognostic value of extra-hepatic bile duct resection (EHBDR) in the surgical management of patients with gallbladder carcinoma (GBC), especially in non-jaundiced patients.MethodsPubMed, EMBASE and the Cochrane Library were searched up to March 1st 2021 for comparative studies between bile duct resected and non-resected groups. RevMan5.3 and Stata 13.0 software were used for the statistical analyses.ResultsEHBDR did not correlate with a better overall survival (OS) (P = 0.17) or disease-free survival (P = 0.27). No survival benefit was also observed in patients with T2N1 (P = 0.4), T3N0 (P = 0.14) disease and node-positive patients (P = 0.75), rather, EHBDR was even harmful for patients with T2N0 (P = 0.01) and node-negative disease (P = 0.02). Significantly higher incidences of recurrent disease (P = 0.0007), postoperative complications (P < 0.00001) and positive margins (P = 0.02) were detected in the bile duct-resected group. The duration of postoperative hospital stay between the two groups was comparable (P = 0.58). Selection bias was also detected in our analysis that a significantly higher proportion of advanced lesions with T3-4 or III-IV disease was observed in the bile duct-resected group (P < 0.00001). EHBDR only contributed to a greater lymph yield (P = 0.01).ConclusionEHBDR has no survival advantage for patients with GBC, especially for those with non-jaundiced disease. Considering the unfairness of comparing OS between jaundiced patients receiving EHBDR with non-jaundiced patients without EHBDR, we could only conclude that routine EHBDR in non-jaundiced patients is not recommended and future well-designed studies with more specific subgroup analyses are required for further validation. 相似文献
3.
4.
5.
6.
Gastro-oesophageal reflux disease (GORD) is symptomatic reflux of gastric contents into the oesophagus. Factors predisposing to GORD are loss of the physiological antireflux barrier and anatomic abnormalities of the oesophagus or diaphragm. Conservative measures and medical management results in resolution of symptoms in a majority of children. Surgery is indicated in the event of failure of medical management or severe complications. Surgical procedures include open or laparoscopic fundoplication in children with normal neurology; fundoplication with or without vagotomy and pyloroplasty; surgical feeding jejunostomy and oesophago-gastric dissociation in the severely neurologically impaired children. 相似文献
7.
《Journal of pediatric surgery》2023,58(6):1213-1218
IntroductionEndoscopic surveillance guidelines for patients with repaired esophageal atresia (EA) rely primarily on expert opinion. Prior to embarking on a prospective EA surveillance registry, we sought to understand EA surveillance practices within the Eastern Pediatric Surgery Network (EPSN).MethodsAn anonymous, 23-question Qualtrics survey was emailed to 181 physicians (surgeons and gastroenterologists) at 19 member institutions. Likert scale questions gauged agreement with international EA surveillance guideline-derived statements. Multiple-choice questions assessed individual and institutional practices.ResultsThe response rate was 77%. Most respondents (80%) strongly agree or agree that EA surveillance endoscopy should follow a set schedule, while only 36% claimed to perform routine upper GI endoscopy regardless of symptoms. Many institutions (77%) have an aerodigestive clinic, even if some lack a multi-disciplinary EA team. Most physicians (72%) expressed strong interest in helping develop evidence-based guidelines.ConclusionsOur survey reveals physician agreement with current guidelines but weak adherence. Surveillance methods vary greatly, underscoring the lack of evidence-based data to guide EA care. Aerodigestive clinics may help implement surveillance schedules. Respondents support evidence-based protocols, which bodes well for care standardization. Results will inform the first multi-institutional EA databases in the United States (US), which will be essential for evidence-based care.Level of EvidenceThis is a prognosis study with level 4 evidence. 相似文献
8.
9.
10.
《中国现代医生》2020,58(32):52-55
目的 分析老年难治性胃食管反流病(rGERD)患者食管动力学特征和反流特点。方法 以我院2017 年2 月~2019 年12 月收治的100 例rGERD 患者为观察对象。按照年龄分为老年组(年龄≥60 岁)42 例和非老年组(年龄<60 岁)58 例。比较两组基线资料、临床表现特征、食管动力学特征、反流特点。结果 老年组与非老年组在性别、BMI 指数、吸烟及饮酒方面比较,差异均无统计学意义(P>0.05)。老年组胸痛、上腹部不适及慢性咳嗽发生率均高于非老年组,差异均有统计学意义(P<0.05)。老年组LESP 及LEPP 水平均低于非老年组,差异均有统计学意义(P<0.05)。老年组酸反流、弱酸反流、非酸反流、气体反流、气液混合反流次数均高于非老年组,差异均有统计学意义(P<0.05)。结论 老年rGERD 患者存在明显的食管动力学异常,且该类患者的反流主要是弱酸反流、非酸反流、气体反流、气液混合反流。 相似文献