全文获取类型
收费全文 | 9182篇 |
免费 | 566篇 |
国内免费 | 157篇 |
专业分类
耳鼻咽喉 | 121篇 |
儿科学 | 155篇 |
妇产科学 | 104篇 |
基础医学 | 1323篇 |
口腔科学 | 181篇 |
临床医学 | 772篇 |
内科学 | 1916篇 |
皮肤病学 | 197篇 |
神经病学 | 593篇 |
特种医学 | 635篇 |
外国民族医学 | 2篇 |
外科学 | 1316篇 |
综合类 | 273篇 |
预防医学 | 585篇 |
眼科学 | 221篇 |
药学 | 745篇 |
1篇 | |
中国医学 | 143篇 |
肿瘤学 | 622篇 |
出版年
2023年 | 78篇 |
2022年 | 279篇 |
2021年 | 377篇 |
2020年 | 182篇 |
2019年 | 255篇 |
2018年 | 272篇 |
2017年 | 199篇 |
2016年 | 315篇 |
2015年 | 406篇 |
2014年 | 490篇 |
2013年 | 544篇 |
2012年 | 872篇 |
2011年 | 759篇 |
2010年 | 382篇 |
2009年 | 372篇 |
2008年 | 550篇 |
2007年 | 438篇 |
2006年 | 448篇 |
2005年 | 358篇 |
2004年 | 347篇 |
2003年 | 336篇 |
2002年 | 269篇 |
2001年 | 193篇 |
2000年 | 171篇 |
1999年 | 158篇 |
1998年 | 100篇 |
1997年 | 77篇 |
1996年 | 65篇 |
1995年 | 43篇 |
1994年 | 33篇 |
1993年 | 29篇 |
1992年 | 35篇 |
1991年 | 47篇 |
1990年 | 29篇 |
1989年 | 35篇 |
1988年 | 38篇 |
1987年 | 26篇 |
1986年 | 29篇 |
1985年 | 33篇 |
1984年 | 18篇 |
1983年 | 24篇 |
1982年 | 17篇 |
1981年 | 17篇 |
1980年 | 15篇 |
1979年 | 17篇 |
1978年 | 14篇 |
1976年 | 11篇 |
1975年 | 11篇 |
1970年 | 12篇 |
1968年 | 9篇 |
排序方式: 共有9905条查询结果,搜索用时 15 毫秒
61.
BACKGROUND: Epoxyeicosatrienoic acids (EETs) are endothelium-derived hyperpolarizing factors that contribute renal protective actions. The aim of this study was to identify the association between genetic variations in soluble epoxide hydrolase (EPHX2, EET-metabolizing enzyme) and kidney allograft dysfunction. MATERIALS AND METHODS: Data from 204 kidney transplant donor-recipient pairs were examined for polymorphisms of exon 8 (R287Q, rs751141 G/A) and 3' untranslated region (3' UTR, rs1042032 A/G) of the EPHX2 gene and correlated with clinical data. RESULTS: The mean duration of follow-up for recipients was 58 +/- 45.3 months who were 39 +/- 11.8 years old at the time of operation and displayed estimated glomerular filtration rate (eGFR) of 68 +/- 16.5 mL/min/1.73 m2 at 1 month after transplantation. AA, AG, and GG genotype frequencies in 3' UTR were 28%, 55%, and 16%, respectively. Twenty-one recipients experienced allograft dysfunction with eGFR <30 mL/min/1.73 m2; 10 had AA genotype of rs1042032 polymorphism (chi-square test; A/A vs A/G+G/G; P = .04). Recipients without rs1042032 polymorphism variant allele showed a significant risk for allograft dysfunction (A/A vs A/G+G/G; P = .04; odds ratio, 2.65; 95% confidence interval [CI], 1.03-6.81). Multivariate analysis of the characteristics of patients using a Cox proportional hazard model showed that the AA genotype of rs1042032 polymorphism was predictive of allograft dysfunction (Hazard Ratio = 3.26; P = .04; 95% CI, 1.08-9.59). CONCLUSION: The present study suggested that the presence of the rs1042032 variant allele in EPHX2 was associated with a protective role for allograft function. 相似文献
62.
Laser Punch-Out for Acne Scars 总被引:6,自引:0,他引:6
Patients with acne scars want smooth facial skin. However, achieving this is difficult with dermabrasion or chemical peeling.
Nor can acne scars be covered with cosmetics, due to their ice-picked or cobblestone appearance. Laser resurfacing is more
effective and safer than other conventional methods due to its precision with depth control and variable methods of surface
cutting. Even depth resurfacing with a laser shows unsatisfactory results, therefore, for the deep-sited acne scar the cutting
methods have to be changed according to the depth and pattern of the scar. For 2 years, starting in January 1996, we treated
71 patients with a high-powered CO2 laser (Ultrapulse). Different resurfacing methods were applied according to the depth and pattern of the scars. For mild
depressed scars, even depth resurfacing was done. For moderate-depth acne scars, the shoulder technique was also used. For
the deepest and ice-picked scars, the laser punch-out was combined. Laser resurfacing was carried out at 300–500 mJ, with
two to five passes. Laser punch-out was done at 500 mJ, with three to seven continuous passes on the ice-picked scar. From
the pathologic findings of acne scars showing that there was thick intradermal scar, we knew that laser punch-out was necessary
for improvement of acne scars. Depth-wide, the ice-picked scars improved by over 80% and the sharp demarcated margin of the
acne scar faded out. Most of the patients with acne scars were satisfied with laser resurfacing. Only six patients had a second
laser treatment, with an interval of 12 months. There were no hypertrophic scars after laser resurfacing, but erythema lasted
for 3–12 months. Patients taking oral retinoic acid were not contraindicated for laser resurfacing but required special caution
because they had atrophic skin and delayed wound healing. Laser resurfacing is the most versatile method for acne scars, with
a high-powered CO2 laser. The laser punch-out method is better than even depth resurfacing for improving deep acne scars and can be combined
with the shoulder technique or even depth resurfacing according to the type of acne scar. 相似文献
63.
Aydin S Unal D Erol H Karaman I Yilmaz Y Sengül E Bayrakli H 《International urology and nephrology》2001,32(4):699-703
Patients with erectile dysfunction, who admitted to 4 different urological centres in Turkey were evaluated in terms of aetiological
factors to establish the aetiology of erectile dysfunction in our population and compare it with the data derived from Western
communities. After the history, physical examination, psychological evaluation and laboratory testing, a clinical diagnosis
was established as primarily psychogenic, organic, or mixed aetiology. Mean patient age was 43.5 years (range 17 to 69), and
9 of the patients were unmarried. Of the patients 53 had vascular risk factors, and 10 reported a history of alcohol abuse.
Eleven patients were using drugs that might interfere with the disorder. In this multicentral study of 115 impotent men, an
organic cause was found in 43%, psychogenic in 47%, and mixed in 19%. Mean age of the overall patients was 43.48. When the
ages of the patients with organic erectile dysfunction and those with psychogenic erectile dysfunction were compared, it was
clearly seen that those with organic erectile dysfunction were much older (52.73 versus 33.02).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
64.
Increased uncoupling protein-2 levels in beta-cells are associated with impaired glucose-stimulated insulin secretion: mechanism of action 总被引:22,自引:0,他引:22
Chan CB De Leo D Joseph JW McQuaid TS Ha XF Xu F Tsushima RG Pennefather PS Salapatek AM Wheeler MB 《Diabetes》2001,50(6):1302-1310
In pancreatic beta-cells, glucose metabolism signals insulin secretion by altering the cellular array of messenger molecules. ATP is particularly important, given its role in regulating cation channel activity, exocytosis, and events dependent upon its hydrolysis. Uncoupling protein (UCP)-2 is proposed to catalyze a mitochondrial inner-membrane H(+) leak that bypasses ATP synthase, thereby reducing cellular ATP content. Previously, we showed that overexpression of UCP-2 suppressed glucose-stimulated insulin secretion (GSIS) in isolated islets (1). The aim of this study was to identify downstream consequences of UCP-2 overexpression and to determine whether insufficient insulin secretion in a diabetic model was correlated with increased endogenous UCP-2 expression. In isolated islets from normal rats, the degree to which GSIS was suppressed was inversely correlated with the amount of UCP-2 expression induced. Depolarizing the islets with KCl or inhibiting ATP-dependent K(+) (K(ATP)) channels with glybenclamide elicited similar insulin secretion in control and UCP-2-overexpressing islets. The glucose-stimulated mitochondrial membrane ((m)) hyperpolarization was reduced in beta-cells overexpressing UCP-2. ATP content of UCP-2-induced islets was reduced by 50%, and there was no change in the efflux of Rb(+) at high versus low glucose concentrations, suggesting that low ATP led to reduced glucose-induced depolarization, thereby causing reduced insulin secretion. Sprague-Dawley rats fed a diet with 40% fat for 3 weeks were glucose intolerant, and in vitro insulin secretion at high glucose was only increased 8.5-fold over basal, compared with 28-fold in control rats. Islet UCP-2 mRNA expression was increased twofold. These studies provide further strong evidence that UCP-2 is an important negative regulator of beta-cell insulin secretion and demonstrate that reduced (m) and increased activity of K(ATP) channels are mechanisms by which UCP-2-mediated effects are mediated. These studies also raise the possibility that a pathological upregulation of UCP-2 expression in the prediabetic state could contribute to the loss of glucose responsiveness observed in obesity-related type 2 diabetes in humans. 相似文献
65.
Sixty-seven patients (78 hips) who were younger than 50 years underwent cementless total hip arthroplasty using a porous-coated acetabular cup, an alumina liner, a 28-mm alumina head, and a proximally porous-coated femoral stem. One patient (1 hip) died and 2 patients (3 hips) were lost to follow-up. The remaining 64 patients (74 hips) were followed for 5 to 6 years. Their mean age at the index operation was 37 years. The mean Harris hip score was 94 points at the time of final follow-up. Four patients (4 hips) had mild thigh pain. All acetabular and femoral components were bone-ingrown, and neither pelvic nor femoral osteolysis was identified. No fracture of the ceramic liner or head was identified. Wear of the ceramic components was undetectable in 27 hips in which measurement was possible. 相似文献
66.
67.
Kim JH Kim HI Lee KW Yu JE Kim SH Park HS Park CG Ihm SH Ha J Kim SJ Lee HK Ahn C Park KS 《Xenotransplantation》2007,14(1):60-66
BACKGROUND: Porcine pancreas is a potential source of material for islet xenotransplantation. However, the difficulty in isolating islets, because of their fragility and the variability of isolation outcome in donor age and breed, represents a major obstacle to porcine islet xenotransplantation. In this study, we compared the islet isolation yield of specific pathogen-free (SPF) Chicago Medical School (CMS) miniature pigs with that of another miniature pig breed and market pigs from a local slaughterhouse. METHODS: Nine adult CMS miniature (ACM) pigs (>12 months), six young CMS miniature (YCM) pigs (6-7 months), four adult Prestige World Genetics (PWG) miniature (APM) pigs (>12 months), and 13 adult market (AM) pigs from a local slaughterhouse were used for islet isolation. RESULTS: The islet yield per gram of pancreas from ACM pigs (9589 +/- 2823 IEQ/g) was significantly higher than that from APM pigs (1752 +/- 874 IEQ/g, P < 0.05), AM pigs (1931 +/- 947 IEQ/g, P < 0.05), or YCM pigs (3460 +/- 1985 IEQ/g, P < 0.05). Isolated islets from ACM pigs were significantly larger than those from AM pigs or YCM pigs. The in vitro and in vivo function of isolated islets showed no difference among experimental groups. The pancreases of ACM pigs contained higher mean islet volume density percentages and larger size of islets than those of AM or APM pigs. CONCLUSIONS: We isolated extremely high yields of well-functioning islets from ACM pigs bred under SPF conditions. SPF CMS miniature pigs should be one of the best porcine islet donors for clinical porcine islet xenotransplantation. 相似文献
68.
Salvage living donor liver transplantation after prior liver resection for hepatocellular carcinoma.
Shin Hwang Sung-Gyu Lee Deok-Bog Moon Chul-Soo Ahn Ki-Hun Kim Young-Joo Lee Tae-Yong Ha Gi-Won Song 《Liver transplantation》2007,13(5):741-746
Salvage liver transplantation has been performed for recurrent hepatocellular carcinoma (HCC) or deterioration of liver function after primary liver resection. Because prior liver resection per se is an unfavorable condition for living donor liver transplantation (LDLT), we assessed the technical feasibility of LDLT after prior hepatectomy, and we compared the outcome of salvage LDLT with that of primary LDLT in HCC patients. Of 342 patients with HCC, 17 (5%) underwent salvage LDLT, with 5 having undergone prior major liver resection and 12 prior minor resection. During salvage LDLT, 12 patients received right lobe grafts, 3 received left lobe grafts, and 2 received dual grafts. There was 1 incident (5.9%) of perioperative mortality. Recipient operation time was not prolonged in patients undergoing salvage LDLT, but bleeding complications occurred more frequently than in patients undergoing primary LDLT. Overall survival rates after salvage LDLT were similar to those after primary LDLT, especially when the extent of recurrent tumor was within the Milan criteria. These results indicate that every combination of prior hepatectomy and living donor liver graft is feasible for patients undergoing salvage LDLT, and the acceptable extent of HCC for salvage LDLT is equivalent to that for primary LDLT. 相似文献
69.
Sohee Lee Cho Rok Lee Seung Chul Lee Seulkee Park Ha Yan Kim Haiyoung Son Sang-Wook Kang Jong Ju Jeong Kee-Hyun Nam Woong Youn Chung Cheong Soo Park Arthur Cho 《Surgical endoscopy》2014,28(4):1068-1075
Background
Using the da Vinci® robotic system, surgeons can complete secure thyroidectomy without noticeable neck scarring. This study compared the surgical completeness of transaxillary robotic thyroidectomy (RT) with conventional open procedures (OT) in treating papillary thyroid carcinoma (PTC) patients.Materials and methods
From April 2009 through February 2011, 94 PTC patients underwent total thyroidectomy with central compartment neck dissection (CCND) at Yonsei University College of Medicine. All patients received 1.1 GBq radioactive iodine (RAI) ablation, post-therapy whole-body scans (TxWBS), and diagnostic WBS (DxWBS) 1 year later. We prospectively compared patient clinicopathologic characteristics and surgical completeness between the two groups.Results
Fifty-one patients underwent OT and 43 underwent RT. Mean age was significantly younger in the RT group. Tumor size, capsular-invasion frequency, multifocality, bilaterality, and central nodal metastasis were not different between the two groups. The number of retrieved nodes during CCND did not significantly differ between the groups. There was no significant difference between the OT and RT groups in stimulated thyroglobulin levels acquired during TxWBS and DxWBS. The RAI uptake ratios at TxWBS were significantly higher in the RT group compared with the OT group; however, follow-up DxWBS showed no difference in RAI uptake ratios. Also, the ablation success rate was similar between the two groups. There were no abnormal findings in follow-up neck ultrasonography in either group.Conclusion
Remnant thyroid tissue ablation after transaxillary RT was successfully managed by 1.1 GBq RAI. RT showed similar surgical completeness versus conventional OT, and provides a safe and feasible surgical option for PTC patients. 相似文献70.
Mirosław Banasik Maria Boratyńska Katarzyna Kościelska‐Kasprzak Dorota Kamińska Dorota Bartoszek Marcelina Żabińska Marta Myszka Sławomir Zmonarski Marcin Protasiewicz Beata Nowakowska Agnieszka Hałoń Pawel Chudoba Marian Klinger 《Transplant international》2014,27(10):1029-1038
Non‐HLA antibodies (Abs) targeting vascular receptors are thought to have an impact on renal transplant injury. Anti‐angiotensin II type 1‐receptor‐activating antibodies (anti‐AT1R) have been mentioned to stimulate a severe vascular rejection, but the pretransplant screening has not been introduced yet. The aim of our study was to assess the incidence and importance of anti‐AT1R antibodies and their influence on renal transplant in the 1st year of observation. We prospectively evaluated the presence of anti‐AT1R antibodies in 117 consecutive renal transplant recipients in pre‐ and post‐transplant screening. Anti‐AT1R antibodies were observed in 27/117 (23%) of the analyzed recipients already before transplantation. The function of renal transplant was considerably worse in anti‐AT1R(+) group. The patients with anti‐AT1R Abs >9 U/ml lost their graft more often. Biopsy‐proven AR was described in 4/27 (15%) pts in the anti‐AT1R(+) group and 13/90 (14.4%) in the anti‐AT1R(?) group, but more severe cases of Banff IIB or antibody‐mediated rejection (AMR) were more often observed in anti‐AT1R (+) 4/27 (15%) vs. 1/90 (1.1%) in anti‐AT1R(+) (P = 0.009). Patients with anti‐AT1R Abs level >9 U/ml run a higher risk of graft failure independently of classical immunological risk factors. The recipients with anti‐AT1R Abs developed more severe acute rejections described as IIB or AMR in Banff classification. More recipients among the anti‐AT1R‐positive ones lost the graft. Our study suggests monitoring of anti‐AT1R Abs before renal transplantation for assessment of immunologic risk profiles and the identification of patients highly susceptible to immunologic events, graft failure, and graft loss. 相似文献