全文获取类型
收费全文 | 531篇 |
免费 | 41篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 4篇 |
妇产科学 | 4篇 |
基础医学 | 81篇 |
口腔科学 | 7篇 |
临床医学 | 57篇 |
内科学 | 167篇 |
皮肤病学 | 2篇 |
神经病学 | 30篇 |
特种医学 | 16篇 |
外科学 | 88篇 |
综合类 | 4篇 |
一般理论 | 1篇 |
预防医学 | 26篇 |
眼科学 | 7篇 |
药学 | 56篇 |
中国医学 | 1篇 |
肿瘤学 | 35篇 |
出版年
2023年 | 8篇 |
2022年 | 7篇 |
2021年 | 47篇 |
2020年 | 24篇 |
2019年 | 23篇 |
2018年 | 23篇 |
2017年 | 17篇 |
2016年 | 15篇 |
2015年 | 36篇 |
2014年 | 27篇 |
2013年 | 46篇 |
2012年 | 34篇 |
2011年 | 69篇 |
2010年 | 16篇 |
2009年 | 17篇 |
2008年 | 23篇 |
2007年 | 21篇 |
2006年 | 24篇 |
2005年 | 23篇 |
2004年 | 11篇 |
2003年 | 13篇 |
2002年 | 9篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 4篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1936年 | 1篇 |
排序方式: 共有589条查询结果,搜索用时 31 毫秒
1.
Karoly Jakab Brook Damon Françoise Marga Octavian Doaga Vladimir Mironov Ioan Kosztin Roger Markwald Gabor Forgacs 《Developmental dynamics》2008,237(9):2438-2449
The Differential Adhesion Hypothesis (DAH) posits that differences in adhesion provide the driving force for morphogenetic processes. A manifestation of differential adhesion is tissue liquidity and a measure for it is tissue surface tension. In terms of this property, DAH correctly predicts global developmental tissue patterns. However, it provides little information on how these patterns arise from the movement and shape changes of cells. We provide strong qualitative and quantitative support for tissue liquidity both in true developmental context and in vitro assays. We follow the movement and characteristic shape changes of individual cells in the course of specific tissue rearrangements leading to liquid-like configurations. Finally, we relate the measurable tissue-liquid properties to molecular entities, whose direct determination under realistic three-dimensional culture conditions is not possible. Our findings confirm the usefulness of tissue liquidity and provide the scientific underpinning for a novel tissue engineering technology. Developmental Dynamics 237:2438-2449, 2008. (c) 2008 Wiley-Liss, Inc. 相似文献
2.
McLennan NF Brennan PM McNeill A Davies I Fotheringham A Rennison KA Ritchie D Brannan F Head MW Ironside JW Williams A Bell JE 《The American journal of pathology》2004,165(1):227-235
The function of the normal conformational isoform of prion protein, PrP(C), remains unclear although lines of research have suggested a role in the cellular response to oxidative stress. Here we investigate the expression of PrP(C) in hypoxic brain tissues to examine whether PrP(C) is in part regulated by neuronal stress. Cases of adult cerebral ischemia and perinatal hypoxic-ischemic injury in humans were compared with control tissues. PrP(C) immunoreactivity accumulates within neuronal processes in the penumbra of hypoxic damage in adult brain, and within neuronal soma in cases of perinatal hypoxic-ischemic injury, and in situ hybridization analysis suggests an up-regulation of PrP mRNA during hypoxia. Rodents also showed an accumulation of PrP(C) in neuronal soma within the penumbra of ischemic lesions. Furthermore, the infarct size in PrP-null mice was significantly greater than in the wild type, supporting the proposed role for PrP(C) in the neuroprotective adaptive cellular response to hypoxic injury. 相似文献
3.
Mutual inhibition of the binding of Clq and protein A to rabbit IgG immune complexes 总被引:1,自引:0,他引:1
A complex of rabbit IgG antibody with horseradish peroxidase covalently linked to Sepharose 4B was used as an insoluble immune complex for studying the binding of complement factor C1q protein A from Staphylococcus aureus, and its IgG-binding fragments AB and B, to rabbit IgG. It was shown that protein A (mol. wt approx. 42,000) and fragments AB and B (mol. wts approx. 14,000 and 7000, respectively) inhibited the binding of C1q to insoluble immune complex at 4 degrees C. However, at 37 degrees C fragment B did not inhibit this binding. On the other hand, C1q, when bound to an insoluble immune complex, almost completely blocked the binding of protein A and fragment B at both temps. The higher affinity of C1q for its CH2-binding site than of fragment B for its CH2-binding site may explain the displacement of the latter from the CH2 domain. The mutual inhibition of the binding of C1q and protein A (and its smaller fragments) indicates that the binding sites for C1q and protein A are closely located in the CH2 domain. 相似文献
4.
Cristofor I. Simionescu Silvia Ioan Aurelia Flondor Bogadan C. Simionescu 《Macromolecular chemistry and physics.》1988,189(10):2331-2339
Three techniques, i. e., the Lenka extrapolation method, the Stockmayer-Fixman method, and the extrapolation of the Mark-Houwink constants to a = 0,5 were applied to determine the unperturbed dimensions of ultrahigh-molecular-weight poly(isobutyl methacrylate). A correction term, depending on the exponent a of the Mark-Houwink relation, is suggested to be introduced into the Stockmayer-Fixman-Burchard equation. 相似文献
5.
6.
Simona Gurzu Tivadar Bara Calin Molnar Tivadar Bara Vlad Butiurca Hanga Beres Simin Savoji Ioan Jung 《Pathology, research and practice》2019,215(1):82-89
Background
Pancreatic mucinous cystic neoplasms (MCN) are rare tumors that are usually diagnosed in females.Materials and methods
In our department, only four of the 109 consecutive cases of pancreatic tumors (3.67%) were diagnosed as MCNs. In this report, we present the characteristics of these four specific cases which also showed unusual HER-2 positivity and neuroendocrine differentiation.Results
The four MCNs were diagnosed in patients with ages between 46 and 75 years. Other clinical particularities were the following: one benign case, splenic rupture as result of a giant cystic tumor on the tail of the pancreas directly invading the spleen in the second one, metastases in the accessory spleen in the third one and invasion of the abdominal vessels in the fourth case. In all of these cases, the ovarian-like stroma tested positivity for calretinin, progesterone receptor (PR) and, in cases 2 and 3, for AE1/AE3 keratin. The malignant tumor cells were marked by carcinoembryonic antigen, HER-2, maspin, PR and the neuroendocrine markers synaptophysin, CD56, and neuron-specific enolase.Conclusions
These cases highlight the unusually aggressive behavior of pancreatic MCN with invasive carcinomas that share mixed exo- and endocrine components and show epithelial-mesenchymal transition. 相似文献7.
Stela Drgan Marieta Nichifor Ioan Petrariu 《Macromolecular chemistry and physics.》1979,180(9):2085-2093
Samples of styrene/divinylbenzene/acrylonitrile macroporous copolymers were prepared, using polystyrene as inert medium. The initial viscosity average molecular weight of the polystyrene samples were: M?v.i=87000, 98000, 117000 and 218000. The polystyrene samples with the initial molecular weights M?v.i=87000 and M?v.i=117000 were reused as inert media, for many times, until they lost their capacity to produce permanent porosity of the copolymers. The macroporous copolymers were characterized by their permanent porosity and volume swelling. If a polystyrene sample is used for many times, the molecular weight of the polystyrene removed (extracted) is gradually diminished and therefore the permanent porosity of the macroporous copolymers decreases step by step. The reasons responsible for this behaviour are:
- during the copolymerization process a polystyrene with a smaller molecular weight is formed.
- polystyrene parts of high molecular weights are included in the network structure of the macroporous copolymers.
8.
Peciu-Florianu Iulia Régis Jean Levivier Marc Dedeciusova Michaela Reyns Nicolas Tuleasca Constantin 《Neurosurgical review》2021,44(5):2391-2403
Neurosurgical Review - Trigeminal nerve schwannomas (TS) are uncommon intracranial tumors, frequently presenting with debilitating trigeminal and/or oculomotor nerve dysfunction. While surgical... 相似文献
9.
Morosanu Cezar Octavian Priscu Adelina Florian Ioan Stefan 《Neurosurgical review》2021,44(5):2533-2543
Neurosurgical Review - In the context of hydrocephalus, there are a multitude of therapeutic options that can be explored in order to improve patient outcomes. Although the peritoneum is the... 相似文献
10.
Emanuel Darius Cata Charles Van Praet Iulia Andras Pierre Kadula Razvan Ognean Maximilian Buzoianu Daniel Leucuta Cosmin Caraiani Attila Tamas-Szora Karel Decaestecker Ioan Coman Nicolae Crisan 《Translational andrology and urology》2021,10(5):1956
BackgroundThe aim of the current study was to evaluate and compare the learning curves of transrectal magnetic resonance imaging-ultrasound fusion biopsy for two urologists with different backgrounds (Operator 1: experienced, self-trained and Operator 2: novice, trained by a mentor/MRI reading courses).MethodsA cohort of 400 patients who underwent fusion prostate biopsy in our department was analyzed. The learning curves were assessed in terms of overall and clinically significant prostate cancer (PCa) detection rates, percentage of positive biopsy cores/targeted and the percentage of PCa tissue on positive targeted cores.ResultsIncreasing trends were observed for both urologists in terms of all biopsy outcomes during the study time. For the novice urologist, a significant increase was observed for overall PCa detection rate, but not for clinically significant disease (25.44%, P=0.04/15%, P=0.145). Operator 1 showed an increasing diagnosis yield of clinically significant disease up to 104 cases. Similar cancer detection rates were observed when comparing the first and last biopsies performed by both operators. Multivariate analysis adjusted for age, PSA, prostate volume, lesion diameter and PIRADS score showed an increase of PCa detection with 51% for every 52 biopsies performed (P=0.022).ConclusionsWhen starting with magnetic resonance imaging-ultrasound fusion prostate biopsy, mentoring and prostate magnetic resonance imaging reading training allow a novice urologist to demonstrate a good initial PCa detection rate. After about 52 cases, he reached a stable PCa and clinically significant PCa detection rate, that was similar to that of an experienced urologist. 相似文献