全文获取类型
收费全文 | 10462篇 |
免费 | 428篇 |
国内免费 | 63篇 |
专业分类
耳鼻咽喉 | 324篇 |
儿科学 | 485篇 |
妇产科学 | 532篇 |
基础医学 | 725篇 |
口腔科学 | 345篇 |
临床医学 | 873篇 |
内科学 | 2609篇 |
皮肤病学 | 175篇 |
神经病学 | 571篇 |
特种医学 | 442篇 |
外科学 | 2389篇 |
综合类 | 148篇 |
一般理论 | 1篇 |
预防医学 | 224篇 |
眼科学 | 369篇 |
药学 | 400篇 |
中国医学 | 24篇 |
肿瘤学 | 317篇 |
出版年
2024年 | 4篇 |
2023年 | 104篇 |
2022年 | 143篇 |
2021年 | 310篇 |
2020年 | 190篇 |
2019年 | 228篇 |
2018年 | 279篇 |
2017年 | 232篇 |
2016年 | 372篇 |
2015年 | 421篇 |
2014年 | 544篇 |
2013年 | 622篇 |
2012年 | 798篇 |
2011年 | 698篇 |
2010年 | 486篇 |
2009年 | 482篇 |
2008年 | 735篇 |
2007年 | 838篇 |
2006年 | 734篇 |
2005年 | 735篇 |
2004年 | 613篇 |
2003年 | 522篇 |
2002年 | 415篇 |
2001年 | 98篇 |
2000年 | 65篇 |
1999年 | 60篇 |
1998年 | 47篇 |
1997年 | 31篇 |
1996年 | 38篇 |
1995年 | 25篇 |
1994年 | 14篇 |
1993年 | 10篇 |
1992年 | 15篇 |
1991年 | 9篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 5篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1974年 | 1篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
BACKGROUND: In cases of thermal injuries it is always difficult to predict the extent of necrosis to the peripheral ischemic zone. Practically, full-thickness skin burn also affects the underlying muscle, panniculus carnosus, which adheres tightly to the skin. In this proposed model, the muscle which was always partly damaged also covers the ischemic zone of full-thickness burn injury. To evaluate the deeper levels of injury, the status of the micro circulation of thermally affected muscle was evaluated by counting the accumulated radioactive agent, 99mTc methoxyisobutylisonitril (MIBI) in the muscle cells. METHODS: 370 MBq/kg (10 mCi/kg) MIBI was administered intravenously to the animals having burn injuries by a comb device as described in previous literature. Then, 20 minutes after injection, whole burned areas were excised and placed under a gamma camera. Each thermally injured area showed four rectangular defects with lower tracer uptakes than the three adjacent interspaces. The tracer uptake of the burned sites and interspaces was analyzed from the acquired images on a computer, and the degree of injury could be assessed quantitatively. Additionally, specimen counts were obtained from selected burned stripes, interspaces and normal tissue for comparison. RESULTS: Burned sites were evident with lower tracer uptakes whereas interspaces with higher uptakes. Captured activity in interspaces indicated that capillary patency mostly maintained and it permitted the arrival of the radiopharmaceutical to the muscle cells. CONCLUSIONS: Muscle layer, where just below the burn area and tightly attached to the skin, could be assessed as a representative of the extension of the injury. 相似文献
22.
Cengiz Yalnkaya MD Alp Diner MD Erem Gündüz MD Can Fco
lu MD Naci Koer MD Ahmet Aydn 《Pediatric neurology》1999,20(5):351-380
3-Hydroxy-3-Methylglutaryl coenzyme A lyase (HMG-CoA) deficiency is a rare inborn error of leucine catabolism. The disease is characterized by recurrent episodes of metabolic acidosis, hyperammonemia without ketosis, hypoglycemia, lethargy, hepatomegaly, and seizures. This study has evaluated the magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) findings of three patients with HMG-CoA deficiency. The common findings on all of the MRI scans were multiple, coalescent, marked lesions in periventricular white matter and arcuate fibers, most prominently in frontal or periatrial regions that were superimposed on diffuse, slightly hyperintense subcortical white matter signal. Involvement of the caudate nucleus and the dentate nucleus were observed in the reported patients. MRS studies by both STEAM and PRESS spectra of all patients revealed a decrease in N-acetylaspartate and elevation in both myoinositol and choline. A pathologic peak at 1.33 ppm, which is compatible with lactate, and a particular peak at 2.42 ppm in all patients were also found. The combination of both MRI and MRS findings could be considered as being specific in patients with HMG-CoA lyase deficiency. 相似文献
23.
24.
This report presents a case of a male newborn with a severe circumferential amniotic band, treated by single-stage excision of the ring, and microvascular venous anastomosis between the proximal and distal parts of the affected site. No complications were encountered. A microsurgical approach to improve the circulation may be useful in some cases. 相似文献
25.
Esra Arslan Ate Ceren Alavanda enol Demir alayan Keklikkran Wafi Attaallah Osman Cavit
zdoan Ahmet lter Güney 《The Turkish journal of gastroenterology》2022,33(2):81
BackgroundFamilial adenomatous polyposis (OMIM #175100) and MUTYH-associated polyposis (OMIM #608456) are rare cancer-prone disorders characterized by hundreds of adenomatous polyps in the colon and rectum, which have a high probability of malignant transformation. Attenuated familial adenomatous polyposis is a variant of familial adenomatous polyposis, which is a term used for the condition in which patients have less than 100 colorectal polyps. Germline heterozygous Adenomatous polyposis coli (APC) and biallelic MUTYH (mutY DNA glycosylase) pathogenic variations are responsible for familial adenomatous polyposis and MUTYH-associated polyposis respectively. The aim of this study is to discuss the clinical manifestations of patients having pathogenic APC and MUTYH variations.MethodsWe included 27 probands who have more than 10 colonic polyps in this study. After evaluation of their clinical and family histories, the probands were screened for APC and MUTYH variations via next generation sequencing. The family members of the probands carrying pathogenic variations were screened via Sanger sequencing. ResultsAmong 27 probands, pathogenic APC and MUTYH variations were detected in 3 and 6 probands respectively. In the APC gene, 3 novel truncating variations (p.Leu360*, p.Leu1489Phefs*23, and p.Leu912*) were detected in 3 unrelated probands. In the MUTYH gene, only 2 distinct pathogenic variations were detected (p.Pro295Leu and p.Glu480del) in the homozygous or compound heterozygous state.ConclusionIn this study, molecular etiology was clarified in 9 familial polyposis patients. The p.Pro295Leu and p.Glu480del variations seem to be common in the Turkish population and may be considered as a first-step genetic test in Turkish familial polyposis patients showing autosomal recessive inheritance. However more studies are needed to reveal the exact frequency of these variations. 相似文献
26.
27.
Purpose: To report the long-term results of four horizontal rectus muscle recessions that were performed for infantile nystagmus syndrome treatment.Methods: In this case series, patients with infantile nystagmus syndrome who had four horizontal muscle recessions previously were recruited and ophthalmological examination and electronystagmography recordings were performed. Objectively, amplitude and frequency of nystagmus were measured from the recordings and the intensity was calculated. Visual acuity, stereopsis, and alignment were evaluated and compared with the preoperative and postoperative values.Results: The records of the 12 patients who had four horizontal rectus muscle recession surgery were evaluated and six patients (5 male, 1 female) who had regular follow-ups were included in this study. Mean follow-up was 14.17?±?0.41 years (minimum 14 years, maximum 15 years) and mean age of patients at the last visit was 22 years (20-28 years). On subjective evaluation, two-thirds (4/6) of the patients were satisfied with the surgical results and had the impression that after surgery, nystagmus decreased in intensity and head posture improved. On objective evaluation, visual acuity was found to be the same, however, stereopsis improved (preoperatively and postoperatively median stereopsis was 600?sec arc vs 200?sec arc final). The decrease in nystagmus amplitude and frequency was still maintained.Conclusions: Nystagmus surgery on four horizontal rectus muscles has positive effects on binocular function and nystagmus parameters in the long-term follow-up. As we could not treat the primary pathology, the visual acuity was about the same but the decrease in nystagmus amplitude and frequency was still maintained with better stereopsis, and patient satisfaction. 相似文献
28.
29.
Double probing of human spermatozoa for persistent histones, surplus cytoplasm, apoptosis and DNA fragmentation 总被引:1,自引:0,他引:1
Sati L Ovari L Bennett D Simon SD Demir R Huszar G 《Reproductive biomedicine online》2008,16(4):570-579
Individual spermatozoa were assessed with pairs of probes for persistent histones and cytoplasmic retention, persistent histones and DNA fragmentation, and persistent histones and apoptotic markers. The individual spermatozoa were treated sequentially with combinations of probes for these cytoplasmic and nuclear biochemical markers. Sperm fields were recorded with computer-assisted imaging, and staining patterns with the two probes in the same spermatozoa were examined and scored as light, intermediate or dark (mature to arrested-maturity spermatozoa). The effects of arrested sperm maturation were similar with respect to the cytoplasmic and nuclear characteristics of spermatozoa in 84% of cells, indicating that cytoplasmic and nuclear attributes of arrested sperm maturation are related. However, there were moderate (intermediate-dark or intermediate-light patterns, 14.5% of cells) or major (light-dark patterns, 1.6% of cells) discrepancies in the intensity of the double staining patterns. Thus, testing with single maturity markers may not be fully reliable. These findings are important with respect to: (i) arrested sperm maturation; (ii) potential efficacy of antioxidant and similar therapeutic strategies in subfertile men, as spermatozoa with infrastructure defects due to mismaturation or maturation arrest are unlikely to respond to interventions; and (iii) detection of adverse male environmental exposures. 相似文献
30.
Erdem A Erdem M Atmaca S Korucuoglu U Karabacak O 《Reproductive biomedicine online》2008,17(2):199-206
The objective of this cross-sectional study was to identify the prognostic factors that influence the outcome of ovarian stimulation with intrauterine insemination (IUI) cycles using gonadotrophins in couples with unexplained and mild male-factor subfertility. A total of 838 cycles in 456 women with unexplained and mild male-factor subfertility attending a university-based infertility clinic was evaluated. Of these cycles, 139 resulted in pregnancy (16.6% per cycle) and 96 out of 98 ongoing pregnancies resulted in live term birth. Live birth rate per patient and per cycle was 21.1% and 11.4%, respectively. Multivariate logistic regression analysis demonstrated that duration of infertility (P = 0.034), type of infertility (P = 0.003), aetiology of infertility (P = 0.004), number of treatment cycles (P = 0.0001) and number of dominant follicles before human chorionic gonadotrophin (HCG; P = 0.024) were significant independent factors to predict clinical pregnancy. The duration of infertility (P = 0.043), number of treatment cycles (P = 0.0001) and number of dominant follicles before HCG (P = 0.024) were significant independent factors to predict live birth. In conclusion, for subfertile couples having shorter duration of subfertility, multifollicular response to gonadotrophins and in their first treatment cycle are more likely to succeed a live birth with IUI treatment using recombinant gonadotrophins. 相似文献