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51.
Sezgin Gunes Gulgez Neslihan Taskurt Hekim Mehmet Alper Arslan Ramazan Asci 《Journal of assisted reproduction and genetics》2016,33(4):441-454
The study aims to discuss the effects of aging on the male reproductive system. A systematic review was performed using PubMed from 1980 to 2014. Aging is a natural process comprising of irreversible changes due to a myriad of endogenous and environmental factors at the level of all organs and systems. In modern life, as more couples choose to postpone having a child due to various socioeconomic reasons, research for understanding the effects of aging on the reproductive system has gained an increased importance. Paternal aging also causes genetic and epigenetic changes in spermatozoa, which impair male reproductive functions through their adverse effects on sperm quality and count as, well as, on sexual organs and the hypothalamic-pituitary-gonadal axis. Hormone production, spermatogenesis, and testes undergo changes as a man ages. These small changes lead to decrease in both the quality and quantity of spermatozoa. The offspring of older fathers show high prevalence of genetic abnormalities, childhood cancers, and several neuropsychiatric disorders. In addition, the latest advances in assisted reproductive techniques give older men a chance to have a child even with poor semen parameters. Further studies should investigate the onset of gonadal senesce and its effects on aging men. 相似文献
52.
Vasculogenesis and angiogenesis in the early human placenta 总被引:3,自引:0,他引:3
Vasculogenesis and angiogenesis are two consecutive processes during blood vessel development in the human placenta. While vasculogenesis, which is the formation of first blood vessels, is achieved by differentiation of pluripotent mesenchymal cells into haemangiogenic stem cells. The subsequent step, angiogenesis, is characterized by development of new vessels from already existing vessels. In this review, we aim to give an overview of vasculogenesis and angiogenesis during the first trimester of human placental development. Recent studies have shown that at the very early stages of placental development, cytotrophoblasts trigger vasculogenesis and angiogenesis, whereas as pregnancy progresses Hofbauer and stromal cells take over the task of triggering blood vessel development. Important growth factors in this scenario are the vascular endothelial growth factor (VEGF) family and their receptors, as well as Tie-1 and Tie-2. This review depicts the molecular and morphological steps of vasculogenesis and angiogenesis, which can give further insights into human placental development and maturation disorders. 相似文献
53.
The aim of the study was to investigate the distribution and differentiation of cell types in the stroma of human placental stem villi (SV). A total of 14 human term placental tissues were studied. Double immunolabeling was performed for desmin-vimentin, desmin--smooth actin and vimentin--smooth actin. Cytokeratin 7, proliferating cell nuclear antigen immunolabeling was also performed. Parallel tissue samples were examined by transmission electron microscopy. HSCORE was performed for the semi-quantitative analysis of distribution of cells in the stroma of SV. Vimentin-labeled cells were mostly distributed in the subtrophoblastic area. Desmin-vimentin double immunolabeling was mainly localized in the triangular area and to a lesser degree in the perivascular area and vessel walls (p=<0.001). However, desmin- smooth actin labeling was observed predominantly in the vessel wall and perivascular area. Vimentin- smooth actin immunoreactivity was significantly stronger in the triangular and perivascular areas compared to the vessel walls (p=0.003).
Ultrastructurally, cells in the stroma of SV were mesenchyme cells, reticulum cells, fibroblasts, myofibroblasts, smooth muscle cells, and Hofbauer cells, filamented and vacuolated cells. The differentiation of myofibroblasts in the triangular and perivascular areas may play a role in maturation of SV and villous contractility, modulation of the intervillous space and this may have effects on maternofetal placental circulation. 相似文献
54.
Unlü RE Orbay H Ylmaz AD Aksoy E Uraloğlu M Sensöz O 《The Journal of craniofacial surgery》2007,18(3):661-664
The main principle of reconstructive surgery is replacement of the defective tissues with like tissues. A full-thickness defect of the nasal ala should be reconstructed in three layers: innermost mucosal layer, outermost skin, and the cartilage in-between. The aim of this study is to describe a technique for single-stage, three-layer reconstruction of the full-thickness ala nasi defects. This technique was used on three patients with tumors involving the nasal ala. Resulting full-thickness defects are reconstructed with a mucocartilaginous turnover flap planned from the contralateral side. Aesthetically acceptable results are obtained without the compromise of the nasal airway and with minimal donor site morbidity. None of the patients requested a revision operation. In conclusion, this is a novel technique with minimal donor site morbidity and good postoperative results. Moreover, lost tissues are replaced with exactly the same kind of tissues. 相似文献
55.
Omer Salih Akar Sezgin Gunes Ummet Abur Engin Altundag Ramazan Asci Onur Emre Onat Tayfun Ozcelik Gonul Ogur 《Andrologia》2020,52(11):e13739
46,XX testicular disorder of sex development (46,XX TDSD) is a relatively rare condition characterised by the presence of testicular tissue with 46,XX karyotype. The present study aims to reveal the phenotype to genotype correlation in a series of sex-determining region Y (SRY)-positive 46,XX TDSD cases. We present the clinical findings, hormone profiles and genetic test results of six patients with SRY-positive 46,XX TDSD and give the details and follow-up findings of our three of previously published patients. All patients presented common characteristics such as azoospermia, hypergonadotropic hypogonadism and an SRY gene translocated on the terminal part of the short arm of one of the X chromosomes. Mean ± standard deviation (SD) height of the patients was 164.78 ± 8.0 cm. Five patients had decreased secondary sexual characteristics, and three patients had gynaecomastia with varying degrees. Five of the seven patients revealed a translocation between protein kinase X (PRKX) and inverted protein kinase Y (PRKY) genes, and the remaining two patients showed a translocation between the pseudoautosomal region 1 (PAR1) of X chromosome and the differential region of Y chromosome. X chromosome inactivation (XCI) analysis results demonstrated random and skewed XCI in 5 cases and 1 case, respectively. In brief, we delineate the phenotypic spectrum of patients with SRY-positive 46,XX TDSD and the underlying mechanisms of Xp;Yp translocations. 相似文献
56.
57.
58.
Increased levels of soluble adhesion molecules E-selectin and P-selectin in patients with cardiac syndrome X 总被引:1,自引:0,他引:1
Senen K Ileri M Alper A Yetkin F Atak R Hisar I Yetkin E Turhan H Bardakçi H Demirkan D 《Angiology》2005,56(3):273-277
The role of endothelial dysfunction and platelet activation in patients with cardiac syndrome X is controversial. The aim of this study was to investigate the plasma levels of circulating E- and P-selectin molecules in patients with syndrome X. The study included 21 patients with cardiac syndrome X (11 men and 10 women, mean age = 56 +/- 5 years) and 20 patients with significant coronary artery disease who had stable angina pectoris (11 men and 9 women, mean age = 60 +/- 8 years). Twenty-two age- and sex-matched subjects (12 men and 10 women, mean age = 58 +/- 8 years) undergoing diagnosis of atypical chest pain in whom coronary arteries were found normal and exercise test had no signs of ischemia served as the control group. Syndrome X was defined as presence of typical chest pain on exertion or at rest with positive exercise test and angiographically normal epicardial coronary arteries with no evidence of coronary spasm after intracoronary infusion of ergonovine maleate. The mean plasma concentrations of P-selectin were significantly elevated both in patients with coronary artery disease and syndrome X as compared with control subjects (49.15 +/-7.47 and 42.80 +/- 8.93 vs 22.63 +/-6.47 ng/mL, p < 0.001). Similarly, both patients with coronary artery disease and syndrome X had higher plasma concentrations of E-selectin than the control group (78.85 +/- 16.69 and 68.38 +/- 15.30 vs 36.43 +/- 4.72 ng/mL, p < 0.001). In conclusion, patients with syndrome X had increased plasma concentrations of soluble adhesion molecules, E-selectin and P-selectin, reflecting an ongoing chronic inflammation involved with endothelial dysfunction and enhanced platelet activation/damage in this setting. 相似文献
59.
Sami Salihu Blerim Krasniqi Osman Sejfija Nijazi Heta Nderim Salihaj Agreta Geci Milaim Sejdini Hysni Arifi Ramazan Isufi Brett A. Ueeck 《International surgery》2014,99(2):161-165
The aim of this study was to analyze the association of potential risk factors such as positive family cleft history, smoking, use of drugs during pregnancy, and parental age with oral clefts in offspring within the Kosovo population. We conducted a population-based case-control study of live births in Kosovo from 1996 to 2005. Using a logistic regression model, 244 oral cleft cases were compared with 488 controls. We have excluded all syndromic clefts. Heredity increases the risk of clefts in newborns [odds ratio (OR) = 8.25, 95% confidence interval (CI) 3.12–23.52]. Clefts were also associated with smoking (OR = 1.87, 95% CI 0.75–4.08), use of drugs during pregnancy (OR = 2.25, 95% CI 0.82–5.12), increasing maternal age (OR = 1.83, 95% CI 1.42–2.49), and increasing paternal age (OR = 1.3, 95% CI 1.2– 1.4). We found heredity to be the most important factor for cleft occurrence in Kosovar newborns. Another significant potential risk factor for occurrence of clefts is the parental age. We found the use of drugs and smoking during pregnancy to be less significant.Key words: Oral clefts, Cleft lip with or without cleft palate, Cleft palate only, Potential risk factors, Logistic regression model, Dummy variablesCleft lip with or without cleft palate and isolated cleft palate are the most common facial birth defects. The etiology involves complex interactions between genetic and environmental factors.1 Genetic factors appear to create the most susceptibility for clefts. When environmental factors (i.e., triggers) interact with a genetically susceptible genotype, a cleft develops during an early stage of development.2 The aim of this study was to analyze the association of potential risk factors such as positive family cleft history, smoking, use of drugs during pregnancy, and parental age with oral clefts in offspring in Kosovo. Risk factors vary among populations, and our ultimate goal was to provide data that may show new potential risk factors influencing the occurrence of clefts in Kosovo. With this new information, we hope to increase public awareness of such risks and thereby help reduce the incidence of cleft in Kosovo. 相似文献
60.
Taner Akar Mustafa Karapirli Ramazan Akcan Birol Demirel Barış Akduman Ahmet Zahit Dursun Serhat Sari Alper Özkök 《Archives of gerontology and geriatrics》2014
According to World Health Organization, the life expectancy at birth is increasing. An increase in life expectancy might result in increased morbidity and mortality in elderly. The increase in the elderly population also leads to an increase in medico-legal problems, as well. Autopsy is of high importance for determination of cause of death in clinical and forensic cases. The purpose of this study was to find out general characteristics elderly deaths by examining forensic autopsy records. 相似文献