全文获取类型
收费全文 | 5139篇 |
免费 | 465篇 |
国内免费 | 85篇 |
专业分类
耳鼻咽喉 | 56篇 |
儿科学 | 45篇 |
妇产科学 | 114篇 |
基础医学 | 687篇 |
口腔科学 | 168篇 |
临床医学 | 431篇 |
内科学 | 625篇 |
皮肤病学 | 123篇 |
神经病学 | 309篇 |
特种医学 | 75篇 |
外国民族医学 | 1篇 |
外科学 | 1065篇 |
综合类 | 366篇 |
预防医学 | 735篇 |
眼科学 | 32篇 |
药学 | 558篇 |
1篇 | |
中国医学 | 55篇 |
肿瘤学 | 243篇 |
出版年
2024年 | 3篇 |
2023年 | 120篇 |
2022年 | 140篇 |
2021年 | 186篇 |
2020年 | 210篇 |
2019年 | 232篇 |
2018年 | 221篇 |
2017年 | 217篇 |
2016年 | 182篇 |
2015年 | 225篇 |
2014年 | 392篇 |
2013年 | 419篇 |
2012年 | 276篇 |
2011年 | 294篇 |
2010年 | 234篇 |
2009年 | 212篇 |
2008年 | 209篇 |
2007年 | 197篇 |
2006年 | 181篇 |
2005年 | 162篇 |
2004年 | 144篇 |
2003年 | 121篇 |
2002年 | 113篇 |
2001年 | 83篇 |
2000年 | 82篇 |
1999年 | 75篇 |
1998年 | 79篇 |
1997年 | 77篇 |
1996年 | 53篇 |
1995年 | 72篇 |
1994年 | 45篇 |
1993年 | 43篇 |
1992年 | 39篇 |
1991年 | 33篇 |
1990年 | 33篇 |
1989年 | 29篇 |
1988年 | 34篇 |
1987年 | 36篇 |
1986年 | 43篇 |
1985年 | 35篇 |
1984年 | 21篇 |
1983年 | 13篇 |
1982年 | 17篇 |
1981年 | 19篇 |
1980年 | 9篇 |
1979年 | 9篇 |
1978年 | 9篇 |
1977年 | 5篇 |
1974年 | 2篇 |
1972年 | 2篇 |
排序方式: 共有5689条查询结果,搜索用时 15 毫秒
1.
A molecular perspective for the use of type IV tyrosine kinase inhibitors as anticancer therapeutics
《Drug discovery today》2022,27(3):808-821
Tyrosine kinases are enzymes that can transfer a phosphate group from ATP to a specific protein tyrosine, serine or threonine residue within a cell, operating as a switch that can turn ‘on’ and ‘off’ causing different physiological alterations in the body. Mutated kinases have been shown to display an equilibrium shift toward the activated state. Types I–III have been studied intensively leading to drugs like imatinib (type II), cobimetinib (type III), among others. It is the same scenario for types V–VII; however, there is a lacuna in information regarding type IV inhibitors, although recently some advances have surfaced. This review aims to accumulate the knowledge gained so far about type IV inhibitors. 相似文献
2.
3.
《Pancreatology》2022,22(2):270-276
Backgroundand purpose: Zinc is an essential element for human health and plays an important role in metabolic, immunological and other biological processes. The present study was conducted to investigate the association between zinc deficiency (ZD) and the perioperative clinical course in patients with pancreatic ductal adenocarcinoma (PDAC).MethodsOf 216 patients with PDAC who underwent elective pancreatectomy between 2013 and 2017 at our institution, 206 patients with sufficient clinical data were retrospectively reviewed. The perioperative variables were compared and the risk factors associated with infectious complications were identified.ResultsZD was preoperatively present in 36 (17.5%) of 206 patients with PDAC. In the patients of the ZD group, a higher proportion of males, higher preoperative modified Glasgow prognostic scores, a higher neutrophil-to-lymphocyte ratio, and a higher occurrence of postoperative infectious complications after pancreatectomy were observed, compared to the non-ZD group. By a univariate analysis, three risk factors were significantly associated with infectious complications after pancreatectomy: ZD (vs non-ZD: p = 0.002), serum albumin <3.5 g/dl (vs ≥ 3.5 g/dl: p = 0.005), and the procedure of pancreaticoduodenectomy (vs others: p = 0.013). By multivariate logistic regression analysis, the occurrence of infectious complications was significantly associated with ZD (OR 3.430, 95%CI 1.570 to 7.490, p = 0.002) and the procedure of pancreaticoduodenectomy (OR 2.030, 95%CI 1.090 to 3.770, p = 0.025).ConclusionsThe current study newly demonstrated that ZD could serve as a preoperative predictor of infectious complications after pancreatectomies in the patients with PDAC. 相似文献
4.
5.
6.
P. Van Camp L. Verstraete B. Van Loon J. Scheerlinck E. Nout 《International journal of oral and maxillofacial surgery》2021,50(5):643-648
This study was undertaken to evaluate the infection rate following orthognathic surgery and to identify possible risk factors. A retrospective study was conducted. Patients undergoing orthognathic surgery from August 1, 2017 to July 31, 2018 were included. The outcome variable was surgical site infection (SSI). All data were analysed with respect to demographics and procedure specifications. A total of 137 patients (mean age 28.5 ± 12.69 years) were included in this study, of whom 20 (14.6%) developed a SSI. The only risk factor identified was the type of surgery: those undergoing mandibular osteotomies (in bilateral sagittal split osteotomy (BSSO) or bimaxillary osteotomies) were far more likely to develop infections. Third molar teeth were removed during orthognathic surgery in 28.5% of the procedures, and a genioplasty was performed in 10.9%. Removal of osteosynthesis material because of infectious reasons was necessary in 10.2% of patients, with a strong association to previous SSI. In conclusion, this study showed an infection rate of 14.6% with no link to any demographic risk factor. Neither the simultaneous removal of third molar teeth nor genioplasty was found to be a risk factor for SSI. For literature comparison purposes, there is a clear need for the international guidelines defining SSI to be used. 相似文献
7.
M.A. Mashrah T.A. Aldhohrah A. Abdelrehem Moustafa H.M. Al-Sharani A. Alrmali L. Wang 《International journal of oral and maxillofacial surgery》2021,50(1):21-31
Donor site morbidity following radial forearm flap (RFF) harvest remains a controversial issue. The aim of this meta-analysis was to answer the question “Are the range of wrist movements (range of motion, ROM) and hand strength affected after RFF harvesting?” The PubMed, Embase, Scopus, and Cochrane Library electronic databases were systematically searched (to December 2019). Self-controlled studies evaluating hand biomechanics after RFF harvest were included. Weighted mean differences with 95% confidence intervals were calculated using the random-effects model. The outcome variables were ROM, forearm movements, grip, and pinch strengths. Thirteen studies involving a total of 335 patients were included. With the exception of grip strength and supination, which showed statistically significant reductions of about 2.40 kg and 2.86° (P < 0.05), all other ROM, forearm movements, and pinch strengths showed an insignificant difference when the operated hand was compared to the non-operated hand (P > 0.05). Regression analysis showed that the method of donor site closure and size of the donor site defect had an insignificant impact on hand biomechanics. This study confirms the lack of discernible biomechanical morbidity after RFF transfer. The minimal reduction in hand biomechanics after RFF is considered to be clinically negligible. 相似文献
8.
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
9.
Koushik Narayan Subramanyam Abhishek Vasant Mundargi Revanth Potarlanka Prakash Khanchandani 《Injury》2019,50(3):770-776
Introduction
Pin site infection is the commonest complication of Ilizarov external fixation. The aim of the study was to examine if use of antiseptics was superior over control and further if daily dressing was superior to weekly dressing in regular pin site care in reducing the burden of pin site infection in Ilizarov fixators.Patients and methods
A total of 114 patients (2363 pin sites) were randomised to receive regular pin site care alone (30 patients, 638 pin sites) or with additional application of povidone iodine (27 patients, 561 pin sites), silver sulfadiazine (27 patients, 570 pin sites) and chlorhexidine (30 patients, 594 pin sites). The pin tracts were sub-randomised to receive daily (1212 pin sites) or weekly (1151 pin sites) dressings. The primary outcome was pin site infection days rate across all four groups. The secondary outcomes were - mean duration to first episode of infection, differences between daily and weekly dressing groups, mean duration of antibiotic therapy and incidence of re-interventions and sequelae. We also recorded frequency of bacterial pathogens in all microbiological samples submitted. Block randomization using computer-generated random numbers was used. The assessor of outcome was blinded.Results
All patients completed the study. Pin site infection rate days per 1000 pin site days observed was marginally less in chlorhexidine group, but was not statistically significant compared to other antiseptics and control group (Absolute value in control, povidone iodine, silver sulphadiazine and chlorhexidine groups were respectively 2.04?±?4.27, 2.04?±?3.65, 1.85?±?3.37, 1.37?±?2.35, p value 0.92). Daily dressing category showed slightly less pin site infection days rate within each group and overall, but this was also not statistically significant (1.56?±?3.99 versus 2.10?±?5.1, p value 0.35). There was no statistically significant difference among the groups with regard to other secondary outcomes. Methicillin Sensitive Staphylococcus aureus was the most common bacterial pathogen isolated.Conclusion
Use of antiseptics does not offer any advantage in regular pin site care in Ilizarov external fixation and daily pin site care is not superior to weekly pin site care. Empirical therapy in early and low grade pin site infections must be targeted against Staphylococcus. 相似文献10.
Habib Kedir Rebecca Miller Faizaan Syed Mohammed Hakim Hina Walia Dmitry Tumin Christopher McKee Joseph D. Tobias 《Journal of pediatric surgery》2019,54(10):2075-2079
BackgroundAlthough preoperative anemia has been suggested to predict postsurgical morbidity and mortality among infants < 1 year of age, the data were drawn from heterogeneous patient cohorts including severely ill infants undergoing complex, high-risk procedures. We aimed to determine whether untreated preoperative anemia was associated with increased risk of postoperative complications in infants < 1 year of age who underwent pyloromyotomy, a common and relatively simple surgery.MethodsInfants < 1 year of age undergoing pyloromyotomy were identified from the American College of Surgeons (ACS) National Surgical Quality Improvement Program-Pediatric database. Preoperative anemia was defined as a hematocrit ≤ 40% for infants 0–30 days of age and ≤ 30% for infants more than 30 days of age. Patients who received pre- or postoperative blood transfusions were excluded.ResultsWe identified 2948 patients who met our inclusion criteria, of whom 843 were anemic (29%). The overall rate of complications in this cohort was 6%. The most common postoperative complications were readmission (97 cases), surgical site infection (43), reoperation (39), prolonged hospital stay (24), urinary tract infection (3), 30-day mortality (3) and cardiac arrest (2). We found no differences in the incidence of complications in anemic versus nonanemic patients on bivariate analysis or multivariable logistic regression (adjusted odds ratio = 1.2; 95% confidence interval: 0.8–1.7; P = 0.319).ConclusionsIn relatively healthy infants undergoing pyloromyotomy, untreated preoperative anemia was not associated with postoperative compilations and should not be considered a significant risk factor.Level of evidence III. 相似文献