全文获取类型
收费全文 | 539篇 |
免费 | 40篇 |
国内免费 | 3篇 |
专业分类
儿科学 | 7篇 |
妇产科学 | 46篇 |
基础医学 | 77篇 |
口腔科学 | 47篇 |
临床医学 | 47篇 |
内科学 | 103篇 |
皮肤病学 | 27篇 |
神经病学 | 33篇 |
特种医学 | 13篇 |
外科学 | 78篇 |
综合类 | 13篇 |
预防医学 | 24篇 |
眼科学 | 7篇 |
药学 | 31篇 |
肿瘤学 | 29篇 |
出版年
2023年 | 11篇 |
2022年 | 28篇 |
2021年 | 31篇 |
2020年 | 24篇 |
2019年 | 26篇 |
2018年 | 30篇 |
2017年 | 12篇 |
2016年 | 9篇 |
2015年 | 18篇 |
2014年 | 22篇 |
2013年 | 30篇 |
2012年 | 31篇 |
2011年 | 35篇 |
2010年 | 18篇 |
2009年 | 17篇 |
2008年 | 26篇 |
2007年 | 20篇 |
2006年 | 23篇 |
2005年 | 20篇 |
2004年 | 22篇 |
2003年 | 22篇 |
2002年 | 18篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 2篇 |
1998年 | 6篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 8篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1972年 | 3篇 |
1969年 | 2篇 |
1968年 | 1篇 |
1964年 | 3篇 |
排序方式: 共有582条查询结果,搜索用时 15 毫秒
61.
62.
Khalaf Kridin Shira Zelber-Sagi Doron Comaneshter Arnon D. Cohen 《Immunologic research》2017,65(5):1083-1088
The association between pemphigus and hepatitis viruses has not been investigated sufficiently and remains unclear. Our objective was to assess the association between pemphigus and chronic hepatitis B (HBV) and hepatitis C (HCV) infections using a large-scale real-life computerized database. This study was conducted as a cross-sectional study utilizing the database of Clalit Health Services. The proportion of chronic HBV and HCV infections was compared between patients diagnosed with pemphigus and age-, sex-, and ethnicity-matched controls. Univariate analysis was performed using chi-square and Student’s t test, and multivariate analysis was performed using a logistic regression model. A total of 1985 pemphigus patients and 9874 controls were enrolled in the study. The prevalence of HBV chronic infection in patients with pemphigus was significantly higher than in control subjects (1.2 vs. 0.6%, respectively, p = 0.008). The prevalence rate of HCV carrier state was comparable between pemphigus patients and control subjects (1.1 vs. 1.0, respectively, p = 0.732). A multivariate analysis revealed a significant association between pemphigus and HBV with a multivariate odds ratio (OR) of 1.9 [95% confidence interval (CI), 1.2–3.90], whereas no association between pemphigus and HCV was identified (OR 1.1, 95% CI, 0.7–1.7). In conclusion, patients with pemphigus have a greater proportion of chronic HBV but not HCV infection relative to matched controls. 相似文献
63.
Efficacy of grape seed extract gel in the treatment of chronic periodontitis: A randomized clinical study 下载免费PDF全文
64.
65.
The use of phosphodiesterase-5 inhibitors has become the first-line treatment of erectile dysfunction nowadays. The daily application of tadalafil has become a line of treatment of other diseases such as pulmonary hypertension and cardiomyopathy. This study aimed at exploring whether the chronic use of tadalafil has an adverse effect on the testes and semen of old albino rats. Sixty male albino rats were divided into three groups. Group 1: given 2 ml saline orally for 90 days. Group 2: received tadalafil orally (1.8 mg kg(-1) day(-1) for 3 months equivalent to 20 mg day(-1) for 3 months as in human dose) and Group 3: received tadalafil orally (1.8 mg kg(-1) day(-1) for 6 months equivalent to 20 mg day(-1) for 6 months as in human dose). Animals were observed daily for signs of toxicity and mortality. Body weight and food consumption were recorded once a week. After sacrificing the animals, gross examination of the testes was performed in situ and then the epididymis was processed for the evaluation of sperm parameters and testes with other organs relative weight was calculated. Testicular histopathological examination was performed to evaluate microscopic changes in the seminiferous tubules. The mean testicular weight was significantly lower in animals of Group 3, and no significant changes were observed in Group 2. Sperm count showed a significant time-dependent decrease. Sperm motility decreased significantly in both groups with higher effect in Group 3. Incidence of abnormal forms increased in both groups (about 5 and 7 times in Group 2 and 3 respectively). Histological examination revealed mild changes in Group 2 and moderate changes in Group 3 in the form of loosely packed connective stroma around seminiferous tubules, reduction in number of spermatogenic cells with sloughing of many spermatocytes within the lumen of some tubules. Large vacuoles appeared in the tubules which contained a fewer number of sperm. Sperm bundles were degenerated in most tubules and completely absent in others. It is concluded that chronic daily use of tadalafil produces detrimental effects on the structure and function of the testes of old male albino rats which are duration dependent. 相似文献
66.
Objectives
To provide systematic review of the literature on the long-standing complications of genitourinary schistosomiasis. 相似文献67.
Malak Mohammed Al-Hakeem Zeinab Abotalib Khalid Khalaf Alharbi Imran Ali Khan 《Clinical biochemistry》2014
Objectives
Gestational diabetes mellitus (GDM) is recognized as an imbalance between insulin resistance and insulin secretion, leading to maternal hyperglycemia. Previous studies in a Saudi population indicated a high frequency of Paraoxonase 1 glutamine 192 to arginine (PON1 Q192R) polymorphism, suggesting this polymorphism as an additional risk factor. The present study was designed to explore the possible association between the PON1 Q192R polymorphism and GDM in a Saudi population.Methods
This case–control study was carried out in 500 pregnant women, including 200 GDM cases and 300 non-GDM women. Genotyping for PON1 Q192R (rs662) variants was performed by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP).Results
The results of the present study indicates that Q192R polymorphism was significantly associated with GDM in a Saudi population with the minor allele frequency (MAF) (p = 0.0007). Q192R genotypes and alleles showed a strong association with GDM (p = 0.009 and p = 0.0007, respectively).Conclusion
In conclusion, these findings suggest that the PON1 Q192R polymorphism has high MAF in GDM in the studied Saudi population. 相似文献68.
Background
Obesity has become a worldwide epidemic and is associated with significant morbidity and mortality. Many strategies to promote weight loss, including medications and surgical techniques, have been developed; however, few have proven effective. As the rates of obesity and associated complications continue to climb, there is growing pressure on the medical community to develop less invasive procedures that can provide lasting weight loss results.Objectives
One surgical treatment for obesity, available in several countries but not yet approved for use in the United States, is the intragastric balloon (IGB). The IGB is a temporary, space-occupying device placed endoscopically into the stomach to decrease gastric volume and provide a sense of early satiety. Our objective is to highlight potential complications of this device that emergency physicians should be familiar with, in particular, gastric outlet obstruction.Case Report
We report the case of a morbidly obese 63-year-old Middle Eastern man who presented to an emergency department in Texas with mechanical gastric outlet obstruction 2 months after IGB placement. After three endoscopic attempts, the balloon was successfully removed and the obstruction relieved.Conclusion
With an increasingly mobile and obese global population, emergency physicians should be aware of weight loss procedures such as the IGB and appropriate time-sensitive management of high-risk complications. 相似文献69.
Abdulla Khalaf Al-Hwiesh Ibrahiem Saeed Abdul-Rahman Mohammad Ahmad Nasr El-Deen Emmanuel Larbi Jose C. Divino-Filho Fahd Abdul-Aziz Al-Mohanna Krishan L. Gupta 《Peritoneal dialysis international》2014,34(4):368-375
♦ Objective: In a number of patients, the antidiabetic drug metformin has been associated with lactic acidosis. Despite the fact that diabetes mellitus is the most common cause of end-stage renal disease (ESRD) and that peritoneal dialysis (PD) is an expanding modality of treatment, little is known about optimal treatment strategies in the large group of PD patients with diabetes. In patients with ESRD, the use of metformin has been limited because of the perceived risk of lactic acidosis or severe hypoglycemia. However, metformin use is likely to be beneficial, and PD might itself be a safeguard against the alleged complications.♦ Methods: Our study involved 35 patients with insulin-dependent type 2 diabetes [median age: 54 years; interquartile range (IQR): 47-59 years] on automated PD (APD) therapy. Patients with additional risk factors for lactic acidosis were excluded. Metformin was introduced at a daily dose in the range 0.5 - 1.0 g. All patients were monitored for glycemic control by blood sugar levels and HbA1c. Plasma lactic acid levels were measured weekly for 4 weeks and then monthly to the end of the study. Plasma and effluent metformin and plasma lactate levels were measured simultaneously.♦ Results: In this cohort, the median duration of diabetes was 18 years (IQR: 14 - 21 years), median time on PD was 31 months (IQR: 27 - 36 months), and median HbA1c was 6.8% (IQR: 5.9% - 6.9%). At metformin introduction and at the end of the study, the median anion gap was 11 mmol/L (IQR: 9 - 16 mmol/L) and 12 mmol/L (IQR: 9 - 16 mmol/L; p > 0.05) respectively, median pH was 7.33 (IQR: 7.32 - 7.36) and 7.34 (IQR: 7.32 - 7.36, p > 0.05) respectively, and mean metformin concentration in plasma and peritoneal fluid was 2.57 ± 1.49 mg/L and 2.83 ± 1.7 mg/L respectively. In the group overall, mean lactate was 1.39 ± 0.61 mmol/L, and hyperlactemia (>2 mmol/L to 5 mmol/L) was found in 4 of 525 plasma samples (0.76%), but the patients presented no symptoms. None of the patients registered a plasma lactate level above 5 mmol/L. We observed no correlation between plasma metformin and plasma lactate (r = 0.27).♦ Conclusions: Metformin may be used with caution in APD patients with insulin-dependent type 2 diabetes. Although our study demonstrated the feasibility of metformin use in APD, it was not large enough to demonstrate safety; a large-scale study is needed. 相似文献
70.
This work investigates an electrochemical impedance analysis based on synthesized TiO2 nanofibers (NFs) photoanodes, which were fabricated via electrospinning and calcination. The investigated photoanode substrate NFs were studied in terms of physicochemical tools to investigate their morphological character, crystallinity, and chemical contents via scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) analyses. As a result, the studied photoanode substrate NFs were applied to fabricate dye-sensitized solar cells (DSCs), and the electrochemical impedance analysis (EIS) was studied in terms of equivalent circuit fitting and impacts of N-doping, the latter of which was approved via XPS analysis. N-doping has a considerable role in the enhancement of charge transfers, which could be due to the strong interactions between active-site N atoms and the used photosensitizer. 相似文献