全文获取类型
收费全文 | 707篇 |
免费 | 41篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 19篇 |
妇产科学 | 17篇 |
基础医学 | 78篇 |
口腔科学 | 18篇 |
临床医学 | 51篇 |
内科学 | 160篇 |
皮肤病学 | 43篇 |
神经病学 | 51篇 |
特种医学 | 19篇 |
外科学 | 142篇 |
综合类 | 12篇 |
预防医学 | 42篇 |
眼科学 | 25篇 |
药学 | 29篇 |
中国医学 | 8篇 |
肿瘤学 | 30篇 |
出版年
2023年 | 12篇 |
2022年 | 24篇 |
2021年 | 25篇 |
2020年 | 34篇 |
2019年 | 45篇 |
2018年 | 44篇 |
2017年 | 30篇 |
2016年 | 29篇 |
2015年 | 22篇 |
2014年 | 41篇 |
2013年 | 40篇 |
2012年 | 49篇 |
2011年 | 59篇 |
2010年 | 20篇 |
2009年 | 23篇 |
2008年 | 30篇 |
2007年 | 26篇 |
2006年 | 29篇 |
2005年 | 28篇 |
2004年 | 20篇 |
2003年 | 17篇 |
2002年 | 12篇 |
2001年 | 12篇 |
2000年 | 17篇 |
1999年 | 7篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 4篇 |
1991年 | 8篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 2篇 |
排序方式: 共有750条查询结果,搜索用时 15 毫秒
51.
BACKGROUND: This study compares the immediate postoperative outcomes in patients who undergo laparoscopic and open anterior lumbar spinal fusion and describes the learning curve associated with the performance of this procedure. METHODS: The charts of patients who underwent anterior lumbar spinal fusion between January 1995 and July 1999 were reviewed. Data pertaining to the operation and postoperative course were analyzed and compared. RESULTS: Eighty-nine patients underwent anterior lumbar spinal fusion. Fourteen patients were excluded; a full analysis was performed on the records of the remaining 75 patients. Fifty-five patients underwent an attempted laparoscopic procedure, and 20 patients underwent an open procedure. The conversion rate was 38% (21/55 patients) in the group who underwent the laparoscopic procedure. In the 34 patients whose laparoscopic procedure was completed, there was significantly less blood loss and shorter postoperative ileus, but the operative time was longer, when compared with patients who underwent the open procedure. The laparoscopic procedures performed in 1999 resulted in fewer conversions, less blood loss, and a shorter operating room time, when compared with the laparoscopic procedures in 1998. CONCLUSIONS: Laparoscopic anterior lumbar spinal fusion improves immediate postoperative results when compared with open anterior lumbar spinal fusion. 相似文献
52.
No EEG evidence of acute tolerance to desflurane in swine 总被引:1,自引:0,他引:1
Desflurane is a potent inhaled anesthetic associated with a dose-dependent depression of cortical electrical activity. Recently, it has been suggested that the burst suppression pattern seen in dogs given moderately high doses (2.0 MAC) of desflurane may spontaneously subside. This observation suggests the development of acute tolerance to at least some of the anesthetic effects of this drug. No other volatile anesthetic has been found to produce acute tolerance. We attempted to replicate these findings in domestic swine. Five juvenile swine (25-30 kg) were anesthetized with desflurane in oxygen and during normocapnia were exposed to two doses of desflurane sufficient to induce burst suppression (1.5 and 1.7 MAC) for 35 min at each dose, with a period of EEG recovery (0.6 MAC) before, between (in 3 of 5 animals), and after the high doses. Frontoparietal EEG was continuously recorded and the burst suppression ratio continuously calculated. Suppression was more complete at 1.7 MAC than at 1.5 MAC (98.24 +/- 1.75 vs. 90.80 +/- 3.05%, respectively, mean +/- standard deviation). The degree of burst suppression activity did not change over time at either 1.5 (P greater than 0.33) or 1.7 MAC desflurane (P greater than 0.41). There was no EEG evidence of tolerance to desflurane anesthesia in swine. 相似文献
53.
Omer Dizdar Mutlu Hayran Deniz Can Guven Tolga Birtan Yılmaz Sahand Taheri Abdullah C. Akman 《Current medical research and opinion》2017,33(12):2195-2200
Background: Previous studies have noted a possible association between periodontal diseases and the risk of various cancers. We assessed cancer risk in a cohort of patients with moderate to severe periodontitis.Methods: Patients diagnosed with moderate to severe periodontitis by a periodontist between 2001 and 2010 were identified from the hospital registry. Patients younger than 35 years of age or with a prior cancer diagnosis were excluded. The age- and gender-standardized incidence rates (SIR) were calculated by dividing the number of observed cases by the number of expected cases from Turkish National Cancer Registry 2013 data.Results: A total of 280 patients were included (median age 49.6, 54% female). Median follow-up was 12 years. Twenty-five new cancer cases were observed. Patients with periodontitis had 77% increased risk of cancer (SIR 1.77, 95% CI 1.17–2.58, p?=?.004). Women with periodontitis had significantly higher risk of breast cancer (SIR 2.40, 95% CI 0.88–5.33) and men with periodontitis had significantly higher risk of prostate cancer (SIR 3.75, 95% CI 0.95–10.21) and hematological cancers (SIR 6.97, 95% CI 1.77–18.98).Conclusion: Although showing a causal association necessitates further investigation, our results support the idea that periodontitis might be associated with increased cancer risk, particularly with hematological, breast and prostate cancers. 相似文献
54.
Omid Mohammad Tavakoli-Rouzbehani Vahid Maleki Mahdi Shadnoush Ehsaneh Taheri Mohammad Alizadeh 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2020,28(2):779
ObjectivesNigella sativa (NS) is a known medicinal herb with numerous therapeutic effects such as antidiabetic, anti-proliferative, anti-inflammatory, and anti-cancer activities. It has been indicated that NS can regulate cellular metabolism by adjusting transduction signaling pathways. Adenosine monophosphate-activated protein kinase (AMPK) is one of the main physiological processes, such as energy hemostasis, cellular metabolism, and autophagy regulators. Herb-derived medicines have always been considered as one of the main AMPK activators, and surprisingly recent data has demonstrated that it can be a target for NS and its derivatives.Evidence acquisitionThe literature search was conducted in PubMed, SCOPUS, Embase, ProQuest, and Google Scholar electronic resources. Published articles up to September 2020 were considered, and those of which investigated Nigella sativa effects on the AMPK pathway after meeting the inclusion criteria were included.ResultsThe search was performed on several online databases such as PubMed, Scopus, Embase, ProQuest, and Google Scholar from inception until January 2020. Among the initial search, 245 studies were found. After removing duplicated data and meeting the inclusion criteria, only 14 studies were selected. They included the effects of NS and its bioactive compounds as anti-hyperglycemic (n = 5), on liver function (n = 4), cancers (n = 3), and on Neuroinflammation and Atherosclerosis (n = 2). Most of the included studies are animals or in-vitro investigations.ConclusionIn this review, we discuss the latest findings on the molecular mechanism of NS effecting the AMPK signaling pathway. We also focus on the therapeutic effects of NS, including the prevention and treatment of metabolic and pro-inflammatory disease by targeting the AMPK pathway.Graphical abstract 相似文献
55.
Sedigheh Asgary Leila Salehizadeh Marzieh Taheri Nicholas D. Spence Maryam S. Farvid 《Journal of the American College of Nutrition》2018,37(4):286-292
Objective: Alternative medicine and herbal drugs have been taken into account for managing cardiovascular risk factors. Sumac (Rhus coriaria L.) is rich in biologically active ingredients known to improve cardiovascular health. We investigated the effect of sumac on systolic (SBP) and diastolic (DBP) blood pressure, flow-mediated dilation (FMD), body mass index (BMI), and serum concentrations of lipids and fasting blood sugar (FBS) in participants with hyperlipidemia in a triple-blind randomized placebo- controlled crossover trial.Methods: Thirty adults with dyslipidemia (mild to moderate elevation of plasma total cholesterol and/or triglycerides [TG; total cholesterol ≥ 6.0 mmol/L or TG ≥ 1.7 mmol/L and TG ≤ 5.0 mmol/L]) were assigned randomly to a sumac or a placebo group. Participants in the sumac group received sumac capsules (500 mg/twice daily) for the first 4 weeks, followed by 2 weeks’ washout period; the patients were then switched to a 4-week interval and received placebo for 4 weeks in the second period. The placebo group received these treatments in reverse order. FMD, BMI, SBP, DBP, lipids, and FBS were measured at baseline and after each period. Results: Differences between placebo group and sumac group (placebo-sumac) were significantly decreased for BMI (0.21 ± 0.075 kg/m2), SBP (1.87 ± 0.83 mm Hg), DBP (1.32 ± 0.46 mm Hg), and total cholesterol (14.42 ± 4.95 mmol/L) and significantly increased for FMD (?0.23% ± 0.065%). Plasma level of TG did not change significantly across the treatment. Conclusion: Sumac consumption may decrease cardiovascular risk factors in persons with mild to moderate hyperlipidemia. 相似文献
56.
This study evaluated the effects lavandula angustifolia (LAF) and its coadministration with Zataria multiflora (ZM) on the learning and memory of prenatal lead exposed adult male offspring rats. Pregnant rats received tap water containing 0.2% lead acetate throughout the gestation period. Two male offspring from each mother (2?months old, weighing 180–200?g) were randomly selected and were treated with saline, LAF (50, 100 &; 200?mg/kg/ip/20d), ZM (50, 200?mg/kg/ip/20d) and combination of effective and ineffective doses of LAF and ZM. The results showed spatial memory deficits in antenatally lead-exposed male offspring in Morris water maze test, which ameliorates following the effective doses of LAF and ZM methanolic extract via unknown mechanism(s). 相似文献
57.
SMJ Mortazavi MA Mosleh-Shirazi AR Tavassoli M Taheri AR Mehdizadeh SAS Namazi A Jamali R Ghalandari S Bonyadi M Haghani M Shafie 《Dose-response》2013,11(2):281-292
The aim of this study was to investigate the effect of pre-irradiation with microwaves on the induction of radioadaptive response. In the 1st phase of the study, 110 male mice were divided into 8 groups. The animals in these groups were exposed/sham-exposed to microwave, low dose rate gamma or both for 5 days. On day six, the animals were exposed to a lethal dose (LD). In the 2nd phase, 30 male rats were divided into 2 groups of 15 animals. The 1st group received microwave exposure. The 2nd group (controls) received the same LD but there was no treatment before the LD. On day 5, all animals were whole-body irradiated with the LD. Statistically significant differences between the survival rate of the mice only exposed to lethal dose of gamma radiation before irradiation with a lethal dose of gamma radiation with those of the animals pre-exposed to either microwave (p=0.02), low dose rate gamma (p=0.001) or both of these physical adapting doses (p=0.003) were observed. Likewise, a statistically significant difference between survival rates of the rats in control and test groups was observed. Altogether, these experiments showed that exposure to microwave radiation may induce a significant survival adaptive response. 相似文献
58.
59.
Leila Azadbakht Mohsen Akhavanzanjani Marzieh Taheri Jafar Golshahi Fahimeh Haghighatdoost 《International journal of food sciences and nutrition》2016,67(2):161-169
To assess the association between dietary glycemic index (GI), glycemic load (GL) and dietary quality indices in Iranian adults. This cross section was conducted among 1571 Iranian adults aged ≥19 years. GI, GL and diet quality indices were estimated by 24-h recall and DDS was calculated using a validated 48-item food frequency questionnaire. Participants who were in the top tertile of GI had lower healthy eating index (HEI) (57.2?±?7.8 versus 55.6?±?8.7; p?0.001), dietary diversity score (DDS) (3.6?±?0.9 versus 3.3?±?1.1; p?0.001) and nutrient adequacy ratios (NARs) for Zn, Ca, vitamin C and B2. Individuals in the lowest tertile of GL had lower HEI, MAR and NARs for Zn, vitamin B2, B3, B6, B12, vitamin D. Both GI and GL were positively related to dietary diversity score (DED) (p?0.001). The inverse associations for GI and GL with diet quality indices may suggest the relevance of carbohydrate source in determining the diet quality indices. 相似文献
60.
OBJECTIVE: To more clearly elucidate the conflicting results that have been obtained after oral calcitriol pulse therapy on lipid, glucose, and calcium levels in hemodialysis (HD) patients, and to determine safety of oral calcitriol pulse therapy in a combination with calcium carbonate. DESIGN: A randomized, crossover, placebo-controlled study. SETTING: HD centers in 3 teaching university hospitals. PATIENTS: Forty-eight chronic HD patients. METHODS: HD patients were randomized into 2 groups. Each group (n = 24), in addition to 4.5 g calcium carbonate daily, received either oral calcitriol pulse therapy or placebo twice weekly at the end of HD, sessions for 3 months, after which the 2 therapeutic groups were crossed-over, and for an additional 3 months, the calcitriol group received placebo, and the placebo group was put on calcitriol. Serum triglyceride, total cholesterol, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), total calcium, alkaline phosphatase, proteins, phosphorus, parathyroid hormone (PTH), blood pH, and glucose were measured at random and at the end of 3 and 6 months of the trial. RESULTS: After calcitriol therapy, triglyceride, serum PTH, total alkaline phosphatase, and fasting blood sugar significantly decreased, but total serum calcium significantly increased, whereas other examined parameters remained unchanged compared with the other groups. Calcium, phosphorus, calcium x phosphorus product, PTH levels, and all of these parameters were optimized in 18 (37.5%), 22 (45.8%), 34 (70.8%), 30 (62.5%), and 12 (%25) cases, respectively, in the calcitriol groups. No significant side effect was seen during the trial. CONCLUSION: Our findings indicate that short-term oral calcitriol pulse therapy in combination with calcium carbonate is safe and beneficial for metabolic abnormalities of HD patients; however, its safety for prolonged therapy is yet to be proved. 相似文献