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51.
Fusheng Bai Hong Peng Joseph D. Etlinger Richard J. Zeman 《Pflügers Archiv : European journal of physiology》2010,460(3):657-666
Spinal cord injury not only disrupts axonal tracts but also causes gliotic, fibrotic, and Schwannotic scarring with resulting deposition of chondroitin sulfate proteoglycans (CSPGs) which prevent axonal reconnection and recovery of locomotor function. Here, we determined whether recovery of locomotor function could be promoted after complete transection, by degrading CSPGs enzymatically within the injury site with chondroitinase ABC (chABC) together with treatment with the β2-adrenoceptor agonist, clenbuterol, a neuroprotective agent which can promote regrowth of lower motoneurons. Partial recovery of locomotor function was observed 8–12 weeks postinjury only after combined chABC and clenbuterol treatment. The recovery of locomotor function coincided with the presence of axons caudal to the injury site arising from neurons of the reticular, vestibular, and red nuclei also only with combined chABC and clenbuterol treatment. Axons myelinated by Schwann cells were most prominent in the transection site in the combined treatment group. Clenbuterol treatment activated cAMP response element binding protein within retrogradely traced neurons which has been associated with axonal regrowth. ChABC treatment decreased scarring due to both CSPG and collagen deposition as well as the gap between intact regions of the spinal cord. ChABC also increased numbers of phagocytic cells which remove myelin debris as well as populations of astrocytes thereby aiding blood–spinal cord barrier reformation. Together the results suggest that chABC and clenbuterol can act synergistically to promote recovery of locomotor function. 相似文献
52.
Vondrackova A Vesela K Hansikova H Zajicova Docekalova D Rozsypalova E Zeman J Tesarova M 《Journal of human genetics》2012,57(7):442-448
Cytochrome-c oxidase (COX) deficiency is one of the common childhood mitochondrial disorders. Mutations in genes for the assembly factors SURF1 and SCO2 are prevalent in children with COX deficiency in the Slavonic population. Molecular diagnosis is difficult because of the number of genes involved in COX biogenesis and assembly. The aim of this study was to screen for mutations in 15 nuclear genes that encode the 10 structural subunits, their isoforms and two assembly factors of COX in 60 unrelated Czech children with COX deficiency. Nine novel variants were identified in exons and adjacent intronic regions of COX4I2, COX6A1, COX6A2, COX7A1, COX7A2 and COX10 using high-resolution melting (HRM) analysis. Online bioinformatics servers were used to predict the importance of the newly identified amino-acid substitutions. The newly characterized variants updated the contemporary spectrum of known genetic sequence variations that are present in the Czech population, which will be important for further targeted mutation screening in Czech COX-deficient children. HRM and predictive bioinformatics methodologies are advantageous because they are low-cost screening tools that complement large-scale genomic studies and reduce the required time and effort. 相似文献
53.
Janice Zeman Bonnie Klimes-Dougan Michael Cassano Molly Adrian 《Clinical psychology》2007,14(4):377-401
The need for a multimethod approach to the study of emotion in children and adolescents is crucial, as is a multilevel analysis in which emotional experience is assessed at a variety of levels (Solomon, 2002). This review highlights the critical role of emotion theory when constructing and selecting appropriate assessment tools with a focus on Functionalist theory that emphasizes the importance of contextual variables ( Barrett & Campos, 1987 ). The review begins with an examination of theoretical and pragmatic issues in emotion measurement followed by discussions of four basic methods of emotion assessment (i.e., self-report, other-report, observation, neurophysiology). Implications of emotion assessment for clinical practice and future directions for research conclude the review. 相似文献
54.
Michael Worlicek Benedikt Moser Günther Maderbacher Raphael Zentner Florian Zeman Joachim Grifka Armin Keshmiri 《The Knee》2017,24(4):711-717
Background
Patellofemoral instability may lead to osteoarthritis, anterior knee pain, and patellar luxation. The purpose of this study was to conduct an exploratory investigation into the difference of patellar kinematics of healthy knees during extension/flexion cycles in neutral, varus and valgus alignment.Methods
The three-dimensional patellar kinematics of 10 lower extremities of whole body cadavers were examined during passive motion, in neutral position, and under valgus and varus stress. Kinematics was recorded by means of an optical computer navigation system.Results
The study samples did not significantly differ with regard to mediolateral patellar shift and epicondylar distance. Varus stress led to significantly higher external rotation than valgus stress (P = 0.04) and to a significantly higher lateral patellar tilt than neutral position (P = 0.016) and valgus stress (P = 0.016). No difference was found between valgus stress and neutral position.Conclusion
Analysis of tibiofemoral alignment alone is insufficient for predicting patellar kinematics. 相似文献55.
Jitka Majovska Igor Nestrasil Amy Paulson David Nascene Katarina Jurickova Anna Hlavata Troy Lund Paul J. Orchard Manuela Vaneckova Jiri Zeman Martin Magner Petr Dusek 《Molecular genetics and metabolism》2021,132(3):189-197
ObjectiveDespite profound neurological symptomatology there are only few MRI studies focused on the brain abnormalities in alpha-mannosidosis (AM). Our aim was to characterize brain MRI findings in a large cohort of AM patients along with clinical manifestations.MethodsTwenty-two brain MRIs acquired in 13 untreated AM patients (8 M/5F; median age 17 years) were independently assessed by three experienced readers and compared to 16 controls.ResultsFocal and/or diffuse hyperintense signals in the cerebral white matter were present in most (85%) patients. Cerebellar atrophy was common (62%), present from the age of 5 years. Progression was observed in two out of 6 patients with follow-up scans. Cortical atrophy (62%) and corpus callosum thinning (23%) were already present in a 13-month-old child. The presence of low T2 signal intensity in basal ganglia and thalami was excluded by the normalized signal intensity profiling. The enlargement of perivascular spaces in white matter (38%), widening of perioptic CSF spaces (62%), and enlargement of cisterna magna (85%) were also observed. Diploic space thickening (100%), mucosal thickening (69%) and sinus hypoplasia (54%) were the most frequent non-CNS abnormalities.ConclusionWhite matter changes and cerebellar atrophy are proposed to be the characteristic brain MRI features of AM. The previously reported decreased T2 signal intensity in basal ganglia and thalami was not detected in this quantitative study. Rather, this relative MR appearance seems to be related to the diffuse high T2 signal in the adjacent white matter and not the gray matter iron deposition that has been hypothesized. 相似文献
56.
Research has demonstrated that children who experience familial sexual maltreatment are at risk for developing psychological difficulties characterized by emotional and behavioral dysregulation. Surprisingly, however, little attention has been directed toward identifying processes in emotional development that differ in maltreated and nonmaltreated children. From a developmental psychopathology perspective, the present study examined emotion management skills (i.e., emotional understanding, emotion regulation) in 21 sexually maltreated girls and their nonmaltreated peers to determine how the experience of sexual maltreatment may interfere with normative emotional development. Findings indicated that sexually maltreated girls, in comparison to their nonmaltreated peers, demonstrate lower emotional understanding and decreased ability to regulate their emotions in accordance with cultural expectations. Further, maltreated girls expected less emotional support and more relational conflict from parents in response to sadness displays and from parents and peers in response to anger displays. These findings will be discussed from the functionalist approach to emotional development, emphasizing the importance of social context (e.g., maltreating, nonmaltreating) in the development of children's emotion management skills. 相似文献
57.
A computed tomography (CT) imaging technique called variable resolution x-ray (VRX) detection provides variable image resolution ranging from that of clinical body scanning (1 cy/mm) to that of microscopy (100 cy/mm). In this paper, an experimental VRX CT scanner based on a rotating subject table and an angulated storage phosphor screen detector is described and tested. The measured projection resolution of the scanner is > or = 20 lp/mm. Using this scanner, 4.8-s CT scans are made of specimens of human extremities and of in vivo hamsters. In addition, the system's projected spatial resolution is calculated to exceed 100 cy/mm for a future on-line CT scanner incorporating smaller focal spots (0.1 mm) than those currently used and a 1008-channel VRX detector with 0.6-mm cell spacing. 相似文献
58.
59.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
60.
Richard J. Zeman Jingbo Zhao Yuangfei Zhang Weidong Zhao Xialing Wen Yong Wu Jiangping Pan William A. Bauman Christopher Cardozo 《Pflügers Archiv : European journal of physiology》2009,458(3):525-535
Causes of disuse atrophy include loss of upper motor neurons, which occurs in spinal cord injury (SCI) or lower motor neurons
(denervation). Whereas denervation quickly results in muscle fibrillations, SCI causes delayed onset of muscle spasticity.
To compare the influence of denervation or SCI on muscle atrophy and atrophy-related gene expression, male rats had transection
of either the spinal cord or sciatic nerve and were sacrificed 3, 7, or 14 days later. Rates of atrophy increased gradually
over the first week after denervation and then were constant. In contrast, atrophy after SCI peaked at 1 week, then declined
sharply. The greater atrophy after SCI compared to denervation was preceded by high levels of ubiquitin ligase genes, MAFbx
and MuRF1, which then also markedly declined. After denervation, however, expression of these genes remained elevated at lower
levels throughout the 2-week time course. Interestingly, expression of the muscle growth factor, IGF-1 was increased at 3 days
after denervation when fibrillation also peaks compared to SCI. Expression of IGF-1R, GADD45, myogenin, and Runx1 were also
initially increased after denervation or SCI, with later declines in expression levels which correlated less well with rates
of atrophy. Thus, there were significant time-dependent differences in muscle atrophy and MAFbx, MuRF1, and IGF-1 expression
following SCI or denervation which may result from distinct temporal patterns of spontaneous muscle contractile activity due
to injury to upper versus lower motor neurons. 相似文献