全文获取类型
收费全文 | 354篇 |
免费 | 18篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 23篇 |
妇产科学 | 4篇 |
基础医学 | 29篇 |
口腔科学 | 17篇 |
临床医学 | 33篇 |
内科学 | 97篇 |
皮肤病学 | 6篇 |
神经病学 | 12篇 |
特种医学 | 4篇 |
外科学 | 92篇 |
综合类 | 5篇 |
预防医学 | 2篇 |
眼科学 | 18篇 |
药学 | 16篇 |
中国医学 | 2篇 |
肿瘤学 | 7篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 2篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 9篇 |
2015年 | 30篇 |
2014年 | 25篇 |
2013年 | 30篇 |
2012年 | 26篇 |
2011年 | 22篇 |
2010年 | 14篇 |
2009年 | 20篇 |
2008年 | 35篇 |
2007年 | 36篇 |
2006年 | 34篇 |
2005年 | 17篇 |
2004年 | 18篇 |
2003年 | 14篇 |
2002年 | 8篇 |
2001年 | 6篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1972年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有373条查询结果,搜索用时 15 毫秒
1.
This study aimed to evaluate stallion sperm survival after 24 h of cooled storage in the presence of seminal plasma (SP) derived from the sperm‐rich fractions (SRF) or sperm‐poor fractions(SPF) of the ejaculate, without SP, or in the presence of SP from other stallions. Ejaculates were collected from four stallions using an automated phantom, which separated the semen into five cups. Centrifuged and washed spermatozoa from cup 2 (SRF) were mixed with skim milk extender to a concentration of 100 × 106 sperm/ml and then 1:1 (v/v) with SP from the stallion's own or another stallions’ second (SP‐SRF) or last cup (SP‐SPF). Skim milk extender (K) and skim milk extender supplemented with modified Tyrode's medium (KMT) were used as control treatments. After a 24‐h storage period in a transport container, spermatozoa were evaluated for motion characteristics and plasma membrane integrity by calcein acetoxymethyl (AM)/propidium iodide staining. The percentage of spermatozoa with intact plasma membranes after storage was lower in SP‐SRF than in SP‐SPF, and the highest in K (P < 0.05). Progressive motility (PMOT) was lower for sperm stored in SP‐SRF than for sperm stored in SP‐SPF (P < 0.05), but there was no significant difference in total motility (TMOT). Sperm stored in KMT (P < 0.05) registered the highest TMOT and PMOT percentages. Osmolarity was significantly higher and pH lower in K than in KMT or SP. Treatment with SP‐SPF from three stallions benefited the PMOT of sperm from one stallion. These preliminary findings suggest that SP from SRFs may be more harmful during storage than SP from SPFs. Removal of SP improves sperm survival in KMT extender, and exchanging SP between stallions seems to influence sperm survival. 相似文献
2.
Oxidative stress and enzymatic antioxidant status in patients with nonalcoholic steatohepatitis 总被引:16,自引:0,他引:16
Koruk M Taysi S Savas MC Yilmaz O Akcay F Karakok M 《Annals of clinical and laboratory science》2004,34(1):57-62
Oxidative stress is an important pathophysiological mechanism in nonalcoholic steatohepatitis (NASH). To assess whether there are relationships between oxidative stress and antioxidant enzymes in the development of NASH, we investigated oxidative stress by measuring serum malondialdehyde (MDA) and nitric oxide (NO) and antioxidant status by measuring serum glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and superoxide dismutase (SOD). The study included 18 patients (13 men, 5 women; mean age 42 yr) with biopsy proven NASH and 16 healthy volunteers (10 men, 6 women; mean age 38 yr). Serum levels of MDA, NO, GSH, GSH-Px, GR and SOD were determined by spectrophotometric methods. Serum levels (mean +/- SD) of MDA (6.7 +/- 1.6 vs 2.8 +/- 1.7 nmol/ml, p 0.0001), NO (135 +/- 28 vs 113 +/- 35 mmol/L, p 0.04), GSH (919 +/- 137 vs 770 +/- 128 mmol/L, p 0.003) were increased in patients with NASH vs controls. Serum levels of GSH-Px (1063 +/- 152 vs 1000 +/- 94 U/L) and GR (47 +/- 22 vs 40 +/- 21 U/L) were not singnificantly different in the patients vs controls. However, the serum level of SOD (1.24 +/- 0.32 vs 1.51 +/- 0.37 U/ml, p: 0.04) was significantly decreased. Impaired antioxidant defense mechanisms may be an important factor in the pathogenesis of NASH. Treatment approaches that affect the antioxidant enzymes may be beneficial in patients with NASH. 相似文献
3.
4.
Ozlen Rodop Ozgur Levent Akcay Nesrin Tutas Onur Karadag 《Saudi Journal of Ophthalmology》2015,29(3):205-209
Purpose
To evaluate the efficiency of perforated punctal plug in acquired punctal stenosis.Materials and methods
Forty-five eyes of 33 patients who had epiphora due to punctal stenosis were included in this study. After biomicroscopic examination and lacrimal dilatation punctal stenosis was managed with the perforated punctal plugs in all patients. In the following period epiphora, plug tolerance, lacrimal drainage were evaluated and graded. Lacrimal drainage was evaluated with fluorescein dye disappearing test.Results
The age of the patients ranged between 31 and 80 (mean 55.78 ± 13.11). Preoperatively punctal dilatation and lacrimal system irrigations were performed on all patients. Lacrimal system irrigation was positive in all patients. Perforated punctal plugs were placed in the inferior puncti in all patients. The plugs were explanted 6 months after operation. The follow-up period ranged between 6 and 24 months. Plug tolerance was good in 97.8% of the eyes in the 1st month visit. Epiphora decreased remarkably in 88.9% of the patients 1 month after plug implantation, except one whose plug dropped off spontaneously in 2 weeks. Fluorescein disappearing times were found under 3 min in 97.8% of the eyes after plug explanations.Conclusion
Punctum stenosis is one of the several disorders that cause lacrimal drainage obstruction. Perforated punctal plugs are found convenient and effective in managing punctal stenosis. 相似文献5.
Surgical treatment of axillary artery aneurysm 总被引:2,自引:0,他引:2
Tetik O Yilik L Besir Y Can A Ozbek C Akcay A Gurbuz A 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2005,32(2):186-8; discussion 185
Aneurysms of the axillary artery are rare and dangerous lesions that threaten the upper extremities with vascular and neurologic compromise. Most can be treated effectively with surgical excision and vascular grafting. We retrospectively assessed 4 axillary artery aneurysms upon which we operated from February 1998 through March 2004. Three patients were admitted to our clinic for symptomatic axillary masses. The remaining patient was transported to our clinic emergently due to massive hemorrhage of an enlarging axillary mass that occurred during biopsy of the mass at another hospital. In this patient, the ruptured axillary artery aneurysm was diagnosed by means of emergent upper-extremity selective angiography. All patients were treated surgically by means of aneurysmectomy and graft interpositioning--with polytetrafluoroethylene grafts in 2 patients and saphenous vein grafts in the other 2. Surgical treatment of axillary artery aneurysms is of importance in avoiding thromboembolism and ischemia, which in turn can lead to gangrene and amputation of the affected extremity. For this reason, operative management of such cases should not be delayed. 相似文献
6.
7.
Guntulu Sk Asuman Demirbuga Agageldi Annayev Arzu Akcay Agop tak Gülyüz
ztürk 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2020,24(2):221-229
Therapeutic plasma exchange (TPE) is an effective treatment method in selective indications. Secondary to access and technical features, it is more difficult to apply in pediatric population than adults. The aim of this study is investigate safety, clinical indications, and results of this method in critically ill pediatric patients who need TPE treatment. All of the TPE procedures performed in a pediatric intensive care unit providing tertiary care during 4 years (2015–2019) were evaluated retrospectively. TPE procedures (635) were performed for 135 patients. Median age was 34 months (10‐108). Ninety‐seven patients had mechanical ventilation support. Sepsis with multiple organ failure was the most frequent indication and accounted for 44.4% (n = 60) of the indications followed by hematological and neurological diseases (19.2% and 9.6% respectively). TPE was performed alone in 469 cases (73.9%), in combination with continuous renal replacement therapy in 154 cases (24.2%), and additional to extracorporeal membrane oxygenation in 12 cases (1.9%). Hematological disease and sepsis subgroups had the highest intubation rate, mechanical ventilation period, PRISM score, organ failure count, and mortality. Fresh frozen plasma (FFP) was the most frequently used replacement fluid in 90.4% of the procedures. The most frequent anticoagulant used in TPE was acid citrate dextrose solution (79.3%). Procedural complications were detected in 104 cases (16.3%) and occurred during TPE sessions. Overall survival rate was 78.5%. We found that the non‐survivor group had significantly higher rates of organ failures (P = 0.0001), higher PRISM scores on admission (P = 0.0001), and higher rates of invasive ventilation support needed (P = 0.012). TPE is a treatment method which can be safely provided in healthcare facilities with necessary medical and technical requirements. Although it is riskier to provide such treatment to critically ill children, complications can be minimized in experienced healthcare facilities. Overall results are good and can vary depending on indication. 相似文献
8.
9.
Ahmet Akcay Gurkan Acar Abdullah Sokmen Gulizar Sokmen Ekrem Dogan Hayriye Sayarlioglu 《Renal failure》2013,35(6):464-469
Background. Insulin resistance was an independent predictor of cardiovascular mortality in uremic patients without diabetes. Rosiglitazone (ROS) improves insulin sensitivity in the liver, muscle, and adipose tissue. We prospectively investigated the effects of ROS on cardiac functions by standard (SDE) and tissue Doppler echocardiography (TDI) in continuous ambulatory peritoneal dialysis (CAPD) patients. Methods. A total of 24 CAPD patients (13 males, 11 females; mean age 42.2 ± 14.8 years) were included. Routine blood samples were examined. Left and right ventricular functions were assessed, and myocardial performance index (MPI) was calculated by SDE and TDI at baseline and after 12-month ROS therapy. Left and right atrial volumes were measured and indexed to body surface area. Results. When compared with baseline, after 12 months of ROS treatment, it was shown that early (E) and late (A) diastolic velocities of atrioventricular valves, E/A ratio, mitral E-wave deceleration time (DT), isovolumetric relaxation time (IVRT), and MPI were similar (p > 0.05). Also, no significant changes were detected in LV dimensions, LV mass index, LVEF, LA volume index, or RA volume index measured by SDE before and after ROS therapy (p > 0.05). Left and right ventricular function parameters measured by TDI including Sm, Em, Am, Em/Am ratio, E/Em ratio, and MPI were similar. Conclusion. It was found that there was no negative effect of long-term ROS therapy on cardiac functions measured by SDE and TDI in CAPD patients. 相似文献
10.
The aim of this prospective experimental study was to evaluate the effect of light-emitting diode (LED) photobiomodulation therapy (LPT) on the stability of immediately loaded miniscrews under different force levels, as assessed by resonance frequency analysis (RFA). Sixty titanium orthodontic miniscrews with a length of 8 mm and a diameter of 1.4 mm were implanted into cortical bone by closed flap technique in each proximal tibia of 15 New Zealand white adult male rabbits (n = 30). The animals were randomly divided into irradiated and control groups under different force levels (0, 150, and 300 cN). OsseoPulse? LED device (Biolux Research Ltd.) 618 nm wavelength and 20 mW/cm(2) output power irradiation (20 minutes/day) was applied to the miniscrews for 10 days. The RFA records were performed at miniscrew insertion session (T1) and 21 days after surgery (T2). Wilcoxon and Mann-Whitney U-tests were used for statistical evaluation at P < 0.005 level. It was found that initial primer stability of all miniscrews was similar in all groups at the start of the experimental procedure. Statistically significant differences were found for changes in implant stability quotient (ISQ) values between LED-photobiomodulated group and the control (0 cN, P = 0.001; 150 cN, P < 0.001; and 300 cN, P < 0.001). Significant increase was found in ISQ values of LPT applied miniscrews under 0 cN (+11.63 ISQ), 150 cN (+10.50 ISQ), and 300 cN (+7.00 ISQ) force during observation period. By the increase of force levels, it was determined that ISQ values decreased in non-irradiated control miniscrews. Within the limits of this in vivo study, the present RFA findings suggest that LPT might have a favourable effect on healing and attachment of titanium orthodontic miniscrews. 相似文献