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71.
BACKGROUND: Genetic skeletal disorders of the fetus and infant are a large group of genetic disorders, comprising the groups formerly assigned as skeletal dysplasias (osteochondrodysplasias), dysostoses, and malformation syndromes with a skeletal component. Genetic skeletal disorders may be prenatally detected by ultrasonography or result in intrauterine or early postnatal death, constituting one difficult diagnostic field met by the pathologist who performs the perinatal autopsy. METHODS: In this retrospective study, we have gathered radiologic, physical, histopathologic, and molecular data regarding 41 cases of genetic skeletal disorders diagnosed among 1980 fetal and perinatal autopsies over a 10‐year period. RESULTS: Our series of cases were classified according to the 2006 Nosology and Classification of Genetic Skeletal Disorders. The overall frequency of genetic skeletal disorders was 1:48 autopsies. The FGFR3 group and osteogenesis imperfecta type 2 were the more frequently encountered disorders. The mean gestational age at autopsy was 21.9 weeks (range, 12–37 weeks). A final diagnosis was obtained in 95% of cases. Genetic skeletal disorders were detected by prenatal ultrasound in 90% of cases, with a correct typing of the disorder achieved in only 34%. Molecular analysis was confirmative in 5 cases. CONCLUSIONS: The central role of the perinatal pathologist in collaboration with specialized services is essential for the correct interpretation of the radiologic, physical, and histopathologic findings, to accurately classify specific types of genetic skeletal disorders and enable genetic counseling. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
72.
In the context of randomized clinical trials, multiplicity arises in many forms. One prominent example is when a key endpoint is measured and analyzed both at baseline and after treatment. It is common to analyze each separately, but more efficient to adjust the post‐treatment comparisons for the baseline values. Adjustment techniques generally treat the covariate (baseline value, in this case) as either nominal or continuous. Either is problematic when applied to an ordinal covariate, the former because it fails to exploit the natural ordering and the latter because it relies on an artifical notion of linear prediction and differences between values. We propose new methods for adjusting for ordinal covariates without having to treat them as nominal or continuous. Specifically, the information‐preserving composite endpoint consists of the pair of values for each patient, one at baseline and one after treatment. Some of these patterns will indicate more improvement than others, yet some pairs of patterns are not comparable. Hence, the ordering is only partial. We develop an approach to testing and deriving estimators of magnitudes of the treatment effect based on comparing each observation in one group to each observation in the other group to which it is comparable. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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Cytokinesis in fission yeast is controlled by the Septation Initiation Network (SIN), a protein kinase signaling network using the spindle pole body as scaffold. In order to describe the qualitative behavior of the system and predict unknown mutant behaviors we decided to adopt a Boolean modeling approach. In this paper, we report the construction of an extended, Boolean model of the SIN, comprising most SIN components and regulators as individual, experimentally testable nodes. The model uses CDK activity levels as control nodes for the simulation of SIN related events in different stages of the cell cycle. The model was optimized using single knock-out experiments of known phenotypic effect as a training set, and was able to correctly predict a double knock-out test set. Moreover, the model has made in silico predictions that have been validated in vivo, providing new insights into the regulation and hierarchical organization of the SIN.  相似文献   
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An active coping style displayed under stress – which involves proactive investigatory responses toward environmental threats – has been associated with reduced vulnerability to psychiatric illness. However, the neurobiological determinants of coping styles are not well understood. When rats are exposed to a naturalistic stressor (cat fur) in a group, some individuals in the group show robust active investigation of the stimulus while others show a passive response involving retreat, immobility and close aggregation with conspecifics. Here we explored endocrine and epigenetic correlates of these contrasting coping styles. Male Wistar rats (n = 48) were exposed to cat fur in groups of 4 and the passive and active responders were identified and assessed for endocrine and epigenetic differences. Three days after the final cat fur exposure, active responders had substantially lower plasma levels of corticosterone and progesterone than passive responders. Plasma and testicular testosterone levels did not differ between active and passive responders. Active responders had markedly less methylation of the AVP CGCG promoter region located at base 4970 in the posterodorsal region of the medial amygdala but did not differ in the methylation status of the CCGG sequence located at base 2243. This is in agreement with prior research suggesting that AVP and progesterone act in opposition within the medial amygdala to modulate stress-related behaviors. The present study reports striking endocrine and epigenetic differences between active and passive responders, providing insight into potential systems involved in the manifestation of differing coping styles.  相似文献   
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A series of coumarin analogues bearing a substituted phenyl ring on position 3 were synthesized via a novel methodology, through an intermolecular condensation reaction of 2-hydroxyacetophenones and 2-hydroxybenzaldehyde, with imidazolyl phenylacetic acid active intermediates. The in vitro antioxidant activity of the synthesized compounds was evaluated using two different antioxidant assays (radical scavenging ability of DPPH stable free radical and inhibition of lipid peroxidation induced by the thermal free radical AAPH). Moreover, the ability of the compounds to inhibit soybean lipoxygenase was determined as an indication of potential anti-inflammatory activity.  相似文献   
79.
The synthesis and study of trimethyl-, tributyl- and triphenyltin esters of the 3- and 4-aminobenzoic acids are reported. The triorganotin derivatives are characterized by elemental analyses, FT-IR and solution 1H and 13C NMR spectra. The structure of the trimethyltin 4-aminobenzoate is solved by X-ray diffraction and proves to be polymeric in nature with bridging carboxylates and trigonal bipyramidal tin(IV) environment. However, all the compounds become monomeric in solution with a tetrahedral tin coordination environment in chloroform and trigonal bipyramidal in DMSO due to coordination of the solvent as the NMR spectra have revealed. The compounds exhibit variable cytotoxic activity when tested against Κ562 myelogenous leukaemia, HeLa cervical cancer and HepG2 hepatocellular carcinoma cell lines, with the butyl derivatives being the more effective and the methyl ones the less. Interestingly, their antibacterial action was significantly lower when tested against Escherichia coli, while not appreciable direct interaction with DNA has been observed. The above observations account for a mode of action that may be related to their potential interaction with cell membranes and the subsequent inhibition of various signaling processes.  相似文献   
80.
In vitro ovarian follicle culture is a new frontier in assisted reproductive technology with tremendous potential, especially for fertility preservation. Folliculogenesis within the ovary is a complex process requiring interaction between somatic cell components and the oocyte. Conventional two-dimensional culture on tissue culture substrata impedes spherical growth and preservation of the spatial arrangements between oocyte and surrounding granulosa cells. Granulosa cell attachment and migration can leave the oocyte naked and unable to complete the maturation process. Recognition of the importance of spatial arrangements between cells has spurred research in to three-dimensional culture system. Such systems may be vital when dealing with human primordial follicles that may require as long as three months in culture. In the present work we review pertinent aspects of in vitro follicle maturation, with an emphasis on tissue-engineering solutions for maintaining the follicular unit during the culture interval. We focus primarily on presenting the various 3-dimensional culture systems that have been applied for in vitro maturation of follicle:oocyte complexes. We also try to present an overview of outcomes with various biomaterials and animal models and also the limitations of the existing systems.  相似文献   
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