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41.
The aim of the present study was to determine the differences in epidemiological and clinical manifestations of breast cancer during the war in Croatia and in peacetime. 660 consecutive patients were recorded (656 female and 4 male patients) from Pozesko-Slavonska County. The changes in histopathological features were recorded in war period (1991-1995, 156 patients) and through two control periods, before the war (1981-1990, 282 patients) and after the war (1995-2000, first five months, 223 patients). The relative predictive value was calculated using chi 2-test. The survival was calculated according to Kaplan-Meier analysis of survival. The histopathological analysis showed an equal distribution of noninvasive cancer (in situ cancer) across periods. In the war period, the level of the most common invasive cancer, ductal breast cancer, was lower (57.7%), compared to control periods (71.2%:63.7%:68.2%). Opposite to that, invasive lobular cancer was more common in the war period (3.2%), compared to control periods (0.7%-1.3%). Furthermore, mixed cancer was also increased in the war period (7.1%) compared to control periods (0.7%-2.2%), as was medullar cancer (10.9% vs. 5.5%-5.9%). The study showed statistically significant differences in the survival of patients with different histopathological diagnoses (Log Rank = 47.49, df = 7, p < 0.0001), while the histological grade of tumor, as a predictive factor was not proved to be statistically significant (p > 0.05). This study confirmed the influence of war of war on histopathological incidence of some forms of breast cancer.  相似文献   
42.
Intracellular localization of VDAC proteins in plants   总被引:1,自引:0,他引:1  
Voltage-dependent anion channels (VDACs) are porin-type -barrel diffusion pores. They are prominent in the outer membrane of mitochondria and facilitate metabolite exchange between the organelle and the cytosol. Here we studied the subcellular distribution of a plant VDAC-like protein between plastids and mitochondria in green and non-green tissue. Using in vitro studies of dual-import into mitochondria and chloroplasts as well as transient expression of fluorescence-labeled polypeptides, it could be clearly demonstrated that this VDAC isoform targets exclusively to mitochondria and not to plastids. Our results support the idea that plastids evolved a concept of solute exchange with the cytosol different from that of mitochondria.Abbreviations AOX Alternative oxidase - p Precursor form - POM36 Putative outer mitochondrial membrane proteins of 36 kDa - SSU Small subunit of ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco) - VDAC Voltage-dependent anion channel  相似文献   
43.
44.
In order to analyze the meteorological factors possibly influencing the monosymptomatic optic neuritis in Rijeka County, northwestern part of Croatia, retrospective analysis of all cases diagnosed in Rijeka County in period from 1977 to 2001, was done. Meteorological data on monthly and yearly temperature, humidity, insolation in Rijeka County were collected from Croatian Meteorological and Hydrological Service. In the observed period there were 173 cases of monosymptomatic optic neuritis, female/male ratio was 1.66, and overall incidence was 2.18/100,000 inhabitants. There was no correlation of incidence with average yearly and monthly temperature, humidity, insolation, or month of birth. This is the first study on meteorological factors and optic neuritis in Croatia.  相似文献   
45.
Myoglianin, the Drosophila homolog of the secreted vertebrate proteins Myostatin and GDF-11, is an important regulator of neuronal modeling, and synapse function and morphology. While Myoglianin suppression during development elicits positive effects on the neuromuscular system, genetic manipulations of myoglianin expression levels have a varied effect on the outcome of performance tests in aging flies. Specifically, Myoglianin preserves jumping ability, has no effect on negative geotaxis, and negatively regulates flight performance in aging flies. In addition, Myoglianin exhibits a tissue-specific effect on longevity, with myoglianin upregulation in glial cells increasing the median lifespan. These findings indicate complex role for this TGF-β-like protein in governing neuromuscular signaling and consequent behavioral outputs and lifespan in adult flies.  相似文献   
46.
Encapsulated microbubbles (MBs) serve as endovascular agents in a wide range of medical ultrasound applications. The oscillatory response of these agents to ultrasonic excitation is determined by MB size, gas content, viscoelastic shell properties and geometrical constraints. The viscoelastic parameters of the MB capsule vary during an oscillation cycle and change irreversibly upon shell rupture. The latter results in marked stress changes on the endothelium of capillary blood vessels due to altered MB dynamics. Mechanical effects on microvessels are crucial for safety and efficacy in applications such as focused ultrasound-mediated blood–brain barrier (BBB) opening. Since direct in vivo quantification of vascular stresses is currently not achievable, computational modelling has established itself as an alternative. We have developed a novel computational framework combining fluid–structure coupling and interface tracking to model the nonlinear dynamics of an encapsulated MB in constrained environments. This framework is used to investigate the mechanical stresses at the endothelium resulting from MB shell rupture in three microvessel setups of increasing levels of geometric detail. All configurations predict substantial elevation of up to 150 % for peak wall shear stress upon MB breakup, whereas global peak transmural pressure levels remain unaltered. The presence of red blood cells causes confinement of pressure and shear gradients to the proximity of the MB, and the introduction of endothelial texture creates local modulations of shear stress levels. With regard to safety assessments, the mechanical impact of MB breakup is shown to be more important than taking into account individual red blood cells and endothelial texture. The latter two may prove to be relevant to the actual, complex process of BBB opening induced by MB oscillations.  相似文献   
47.
Abstract

Human dipeptidyl peptidase III (hDPP III) is a zinc-exopeptidase of the family M49 involved in final steps of intracellular protein degradation and in cytoprotective pathway Keap1-Nrf2. Biochemical and structural properties of this enzyme have been extensively investigated, but the knowledge on its contacts with other proteins is scarce. Previously, polypeptide aprotinin was shown to be a competitive inhibitor of hDPP III hydrolytic activity. In this study, aprotinin was first investigated as a potential substrate of hDPP III, but no degradation products were demonstrated by MALDI-TOF mass spectrometry. Subsequently, molecular details of the protein–protein interaction between aprotinin and hDPP III were studied by molecular modeling. Docking and long molecular dynamics (MD) simulations have shown that aprotinin interacts by its canonical binding epitope with the substrate binding cleft of hDPP III. Thereby, free N-terminus of aprotinin is distant from the active-site zinc. Enzyme-inhibitor complex is stabilized by intermolecular hydrogen bonding network, electrostatic and hydrophobic interactions which mostly involve constituent amino acid residues of the hDPP III substrate binding subsites S1, S1', S2, S2' and S3'. This is the first study that gives insight into aprotinin binding to a metallopeptidase.

Communicated by Ramaswamy H. Sarma  相似文献   
48.
To elucidate the role of iron in the pathomechanisms of autoimmune CNS disorders, we estimated the tissue concentrations of Fe2+ in the brain, spinal cord, and liver in the chronic relapsing form of experimental autoimmune encephalomyelitis (EAE). The disease was induced in Dark Agouti (DA) strain of rats, by subcutaneous injection of bovine brain homogenate in complete Freund's adjuvant (CFA). Control rats consisted of unsensitized rats and of rats treated with CFA or saline. The data obtained by clinical assessment and by inductively coupled plasma spectrometry have shown that the attacks of disease (on the 12th and 22nd post-immunization day) were followed by high accumulation of iron in the liver. Additionally, during the second attack of disease, the decreased concentration of Fe2+ was found in cervical spinal cord. The data point to regulatory effects of iron and hepatic trace elements regulating mechanisms in the pathogenesis of EAE.  相似文献   
49.
The aim of this study was to provide an overview of the central nervous system (CNS) tumours epidemiology in Karlovac region, over the 1995-2010 period. We analyzed data on 359 patients (194 men and 165 women), diagnosed with CNS tumours according to the World Health Organization's diagnostic criteria, in period 1995-2010. The data were obtained from the Neurology and Neurosurgery Department, including other medical records. The data were analysed with t-test and chi-square test. A total of 359 cases of tumours in CNS were recorded for the period of 1995-2010, with slight predominance of men (194;54.0%) over women (165;46.0%). Under the assumption of gender equality, we did not detect a significant gender difference in tumour diagnosis (p = 0.279). Mean age at the diagnosis was 64.1 +/- 12.6 years, with significant gender difference: mean age at diagnosis for men was 62.8 +/- 11.6 years, while for women it was 65.7 +/- 13.5 (p = 0.029). The commonest type of all tumours was metastases (144;40.1%). When only primary tumours were analysed, the commonest type was glioblastoma (125;58.15%), followed by meningeoma (44;20.5%). The remaining types were much less frequent, with i.e. 5 recorded cases of the following three types: astrocytoma, ependimoma and oligodendroglyoma (2.3%). These results suggest a commonly encountered epidemiological profile in the region, with commonest metastases, and glioblastoma as the most common primary tumour. Due to difficulties related to patient gravitating hospitals admittance and overall small sample size for more detailed analyses, it remains for future studies to determine potential association of the Homeland war (1991-1995) and the occurrence of CNS tumours.  相似文献   
50.
This work emphasizes new algorithms for 3D edge and corner detection used in surface extraction and new concept of image segmentation in neuroimaging based on multidimensional shape analysis and classification. We propose using of NifTI standard for describing input data which enables interoperability and enhancement of existing computing tools used widely in neuroimaging research. In methods section we present our newly developed algorithm for 3D edge and corner detection, together with the algorithm for estimating local 3D shape. Surface of estimated shape is analyzed and segmented according to kernel shapes.  相似文献   
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