全文获取类型
收费全文 | 3222篇 |
免费 | 197篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 12篇 |
儿科学 | 76篇 |
妇产科学 | 103篇 |
基础医学 | 417篇 |
口腔科学 | 87篇 |
临床医学 | 226篇 |
内科学 | 816篇 |
皮肤病学 | 56篇 |
神经病学 | 228篇 |
特种医学 | 97篇 |
外科学 | 684篇 |
综合类 | 15篇 |
预防医学 | 186篇 |
眼科学 | 68篇 |
药学 | 137篇 |
中国医学 | 7篇 |
肿瘤学 | 220篇 |
出版年
2023年 | 13篇 |
2022年 | 44篇 |
2021年 | 99篇 |
2020年 | 46篇 |
2019年 | 89篇 |
2018年 | 106篇 |
2017年 | 78篇 |
2016年 | 60篇 |
2015年 | 72篇 |
2014年 | 111篇 |
2013年 | 127篇 |
2012年 | 175篇 |
2011年 | 185篇 |
2010年 | 133篇 |
2009年 | 106篇 |
2008年 | 181篇 |
2007年 | 165篇 |
2006年 | 153篇 |
2005年 | 152篇 |
2004年 | 170篇 |
2003年 | 118篇 |
2002年 | 115篇 |
2001年 | 110篇 |
2000年 | 122篇 |
1999年 | 76篇 |
1998年 | 26篇 |
1997年 | 18篇 |
1996年 | 23篇 |
1995年 | 32篇 |
1994年 | 13篇 |
1993年 | 16篇 |
1992年 | 56篇 |
1991年 | 37篇 |
1990年 | 39篇 |
1989年 | 27篇 |
1988年 | 32篇 |
1987年 | 31篇 |
1986年 | 29篇 |
1985年 | 22篇 |
1984年 | 17篇 |
1983年 | 24篇 |
1982年 | 17篇 |
1981年 | 18篇 |
1980年 | 17篇 |
1979年 | 14篇 |
1978年 | 15篇 |
1975年 | 16篇 |
1974年 | 11篇 |
1973年 | 9篇 |
1967年 | 10篇 |
排序方式: 共有3435条查询结果,搜索用时 15 毫秒
51.
Esmolol for potentiation of nitroprusside-induced hypotension: impact on the cardiovascular, adrenergic, and renin-angiotensin systems in man 总被引:4,自引:0,他引:4
R Edmondson O Del Valle N Shah G Wong D Dwyer D Matarazzo A Thorne C Coffey R Bedford 《Anesthesia and analgesia》1989,69(2):202-206
Esmolol infusion at rates of 200, 300, and 400 micrograms.kg-1.min-1 was used to potentiate hypotension (mean arterial pressure = 60 mm Hg) induced with sodium nitroprusside (SNP) in 10 male patients undergoing radical cancer surgery during nitrous oxide-oxygen and fentanyl anesthesia. Heart rate (HR), blood pressure (radial arterial catheter), and plasma levels of renin activity (PRA), norepinephrine (N), epinephrine (E), and dopamine (D) were measured: 1) while patients were awake; 2) after induction of anesthesia (nitrous oxide, 60% in oxygen, fentanyl = 5 micrograms/kg followed by an infusion at 10 micrograms.kg-1.hr-1); 3) after surgery had begun; 4) after 20 minutes of SNP-induced hypotension; 5) after 20 minutes of esmolol at each of the above infusion rates; and 6) after the completion of surgery. Compared to awake values, SNP-induced hypotension (mean infusion rate = 3.1 micrograms.kg-1.min-1 +/- 0.6 SE) during surgery resulted in significant (P less than 0.05) increases in heart rate, PRA, N, and D. Infusion of esmolol resulted in significant (P less than 0.05) dose-dependent reductions in SNP requirement to maintain MAP = 60 mm Hg. At 200 micrograms.kg-1.min-1, SNP requirement was 2.1 micrograms.kg-1.min-1 +/- 0.4, at 300 micrograms.kg-1.min-1, it was 1.0 micrograms.kg-1.min-1 +/- 0.2, and at 400 micrograms.kg-1.min-1, was 0.5 micrograms.kg-1.min-1 +/- 0.3. Concomitant with the decrease in SNP requirement, there were significant reductions in HR and PRA at all infusion rates of esmolol.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
52.
53.
Brian Darrith Nicholas B. Frisch Matthew W. Tetreault Michael P. Fice Chris N. Culvern Craig J. Della Valle 《The Journal of arthroplasty》2019,34(2):221-227
Background
Although some prior work supports the safety of same-day arthroplasty performed in a hospital, concerns remain when these procedures are performed in a free-standing ambulatory surgery center. The purpose of this study is to compare 90-day complication rates between matched cohorts that underwent inpatient vs outpatient arthroplasty at an ambulatory surgery center.Methods
A single-surgeon cohort of 243 consecutive patients who underwent outpatient arthroplasty was matched with 243 inpatients who had the same procedure. One-to-one nearest-neighbor matching with respect to gender, age, American Society of Anesthesiologists Score, and body mass index was utilized. The 486 primary arthroplasties included 178 unicondylar knees (36.6%), 146 total hips (30.0%), 92 total knees (18.9%), and 70 hip resurfacings (14.5%). Ninety-day outcomes including reoperation, readmission, unplanned clinic or emergency department visits, and major and minor complications were compared using a 2-sample proportions test.Results
The 2 cohorts were similar in distribution of demographic variables, demonstrating successful matching. The inpatient and outpatient cohorts both had readmission rates of 2.1% (P = 1.0). With the number of subjects studied, there were no statistically significant differences in rates of major complications (2.1% vs 2.5%, P = 1.0), minor complications (7.0% vs 7.8%, P = .86), reoperations (0.4% vs 2.1%, P = .22), emergency department visits (1.6% vs 2.5%, P = .52), or unplanned clinic visits (3.3% vs 5.8%, P = .19).Conclusion
This study suggests that arthroplasty procedures can be performed safely in an ambulatory surgery center among appropriately selected patients without an increased risk of complications. 相似文献54.
Activation marker expression and apoptotic susceptibility of T-cell clones derived from CD34(+), young and SENIEUR donors 总被引:1,自引:0,他引:1
T-cell clones (TCC) derived from human peripheral blood lymphocytes of a young control, a healthy elderly (SENIEUR) donor, or from CD34(+) hematopoietic progenitor cells were utilised in this study to examine how in vivo and in vitro ageing affects T-cell apoptotic capability. The role of CD25, CD28 and the intracellular proteins, FLICE-inhibitory protein (FLIP), receptor-interacting protein (RIP) and caspase 3 were investigated. We observed an age-related decline in the expression of the IL-2 receptor alpha chain CD25, and absence of the co-stimulatory receptor CD28 on three of the four TCC studied. In young donor- and CD34 cell-derived TCC, but not in SENIEUR donor-derived TCC, we observed an age-related increase in susceptibility of the cells to mFas-L-induced apoptosis, which correlated with the age-related decrease of CD25 expression. Expression levels of full-length RIP and FLIP did not show any correlation to apoptotic susceptibility. However, expression levels of the cleaved form of RIP were greatly reduced in the SENIEUR donor-derived TCC, which together with a trend towards increased caspase 3 activity, could indicate an age-related alteration in utilisation of different apoptotic signalling pathways. 相似文献
55.
56.
57.
Susana Rodríguez Villa María Teresa Suárez Muñiz Ricardo De Dios del Valle Crisanto Alonso Álvarez 《Enfermería clínica》2018,28(1):44-48
Aim
To compare the evaluation of retinographies by a teleophthalmology nurse and primary care physicians (PCP) with an ophthalmologist referral hospital (gold standard).Methods
Cross-sectional study on a random sample of 337 patients on the teleophthalmology programme from January 2010 to January 2015. We analyzed the diagnostic evaluation (whether or not it presented findings of RD) and the therapeutic assessment (whether or not referral to the opthalmology department was needed) which were conducted independently on the sample retinographies by the PCP, a nurse and an ophthalmologist (gold standard). Reliability and concordance between the gold standard and the PCP and the nurse were checked and the statistical analyses were supported using SPSSv.23.00 software and diagnostic test reliability calculators (EPIDAT 4.1).Results
In the diagnosis of RD, the nurse presented: sensitivity (S): 0.96; specificity (Sp): 0.89; PPV: 0.58; NPV: 0.99; Kappa index: 0.67 and PCP: S: 0.98; Sp: 0.99; PPV: 0.96; NPV: 0.99; Kappa index: 0.96.In the referral to ophthalmology assessed by the nurse: S: 0.83; Sp: 0.83; PPV: 0.51; NPV: 0.96; Kappa Index: 0.53 and PCP: S: 0.62; Sp: 0.76; PPV: 0.36; NPV: 0.90; Kappa index: 0.29.Conclusions
A nursing teleophthalmology programme could perform population screening for RD with the same quality as PCP. This would increase coverage, in addition to providing better use of resources by avoiding intermediate patient appointments through PCP and increased health savings. 相似文献58.
Martin O. Weickert Gregory Kaltsas Dieter Hörsch Pablo Lapuerta Marianne Pavel Juan W. Valle Martyn E. Caplin Emily Bergsland Pamela L. Kunz Lowell B. Anthony Enrique Grande Kjell Öberg Staffan Welin Catherine Lombard-Bohas John K. Ramage Ashwin Kittur Qi M. Yang Matthew H. Kulke 《Clinical therapeutics》2018,40(6):952-962.e2
Purpose
In the placebo-controlled Phase III TELESTAR (Telotristat Etiprate for Somatostatin Analogue Not Adequately Controlled Carcinoid Syndrome) trial, the oral tryptophan hydroxylase inhibitor telotristat ethyl significantly reduced bowel movement (BM) frequency during a 12-week, double-blind treatment period in 135 patients with metastatic neuroendocrine tumors with carcinoid syndrome and ≥4 BMs per day. Patients (mean [SD] age, 63.5 [8.9] years; mean [SD] body mass index, 24.9 [4.9] kg/m2) received placebo, telotristat ethyl 250 mg, or telotristat ethyl 500 mg 3 times per day (TID) in addition to somatostatin analogue therapy. Weight loss is associated with uncontrolled carcinoid syndrome and may be associated with reduced survival.Methods
Assessment of the occurrence of weight change ≥3% at week 12 was prespecified in the statistical analysis plan.Findings
In 120 patients with weight data available, weight gain ≥3% was observed in 2 of 39 patients (5.1%) taking placebo TID, 7 of 41 (17.1%) taking telotristat ethyl 250 mg TID, and 13 of 40 (32.5%) taking telotristat ethyl 500 mg TID (P = 0.0017) at week 12. Weight loss ≥3% was observed in 5 of 39 patients (12.8%) taking placebo TID, 4 of 41 (9.8%) taking telotristat ethyl 250 mg TID, and 6 of 40 (15.0%) taking telotristat ethyl 500 mg TID (P = 0.77). Biochemical and metabolic parameters of serum albumin and cholesterol significantly increased (P = 0.02 and P = 0.001, respectively) in patients gaining weight and decreased in patients who lost weight, suggesting an improvement in overall nutritional status.Implications
Up to 32.5% of patients treated with telotristat ethyl experienced significant, dose-dependent weight gain, associated with reduced diarrhea severity and improved biochemical and metabolic parameters. Improved nutritional status could be an additional aspect of telotristat ethyl efficacy among patients with functioning metastatic neuroendocrine tumors. ClinicalTrials.gov identifier: NCT01677910. 相似文献59.
Daniel H. Montes-Cortés José L. Novelo-Del Valle Ivonne M. Olivares-Corichi José V. Rosas-Barrientos Luis J. Jara María Pilar Cruz-Domínguez 《The American journal of emergency medicine》2018,36(9):1570-1576
Hyperammonemia results from hepatic inability to remove nitrogenous products generated by protein metabolism of intestinal microbiota, which leads to hepatic encephalopathy (HE) in chronic liver disease (CLD). In ammonium neurotoxicity, oxidative stress (OxS) plays a pathogenic role. Our objective was to evaluate if intestinal mannitol is as effective and safe as conventional treatment for diminishing hyperammonemia, OxS, and HE in patients with CLD.