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101.
102.
The paired neuronal and glial membranes, or interglial membranes, which are separated by the narrow layer of the extracellular medium, are involved in intercellular communications. In the crayfish stretch receptor, the paired neuroglial membranes contain thin protein bridges (septate junctions) that maintain the intermembrane gap. In some places the paired membranes are locally disorganized. In the altered regions, they comprise the diffuse material in which a few 10–15 nm vesicles are embedded. The development of these defects can lead to formation of 20–30 nm vesicles and perforations in the paired membranes. The presence of such holes can, in principle, disturb ionic gradients and neuronal activity. However, a free passage between contacting neurons and glia is prevented by the diffuse proteolipid material (the product of the membrane disorganization) that seals perforations. As a result, the neuroglial border does not lose its integrity and impermeability for ions so that the sensory neurons save the capability for prolonged regular firing. Unlike the neuroglial border, some perforations in the paired glia–glial membranes are not sealed. This can create the interglial syncytial connections providing the shortcut pathway for transport of ions and metabolites across the glial layers in the crayfish stretch receptor. © 2014 Wiley Periodicals, Inc.  相似文献   
103.
Direct skeletal attachment of limb prostheses is a viable alternative to traditional techniques that are based on a socket-residuum interface. Direct skeletal attachment may be a better or even the only method for patients with a very short residuum and high soft-tissue volume. The problem of integrating the prosthetic pylon with residual skin during direct skeletal attachment of a limb prosthesis has not been solved, and the use of a completely porous prosthetic pylon has not been the subject of focused, systematic research. In this in vivo study, we investigated cell (osteocyte, fibroblast, and keratinocyte) adhesion and penetration into the pores of a titanium pylon implanted in Wistar rats. The porous titanium pylon was implanted in the bone of the thigh residua of four rats. Electronic scanning and morphological analysis demonstrated integration of the pylon with the surrounding skin. These findings support the possibility of developing a natural barrier against the infection associated with direct skeletal attachment of limb prostheses.  相似文献   
104.
Sulbutiamine (isobutyryl thiamine disulfide) is a lipophilic derivative of thiamine used for the treatment of asthenia and other related pathological conditions. It is available over-the-counter in several countries either as a component of nutritional supplements or as a pharmaceutical preparation. The presence of sulbutiamine in urinary doping control samples was monitored to evaluate the relevance of its use in sports. As one of the sulbutiamine metabolites has very close retention time and the same characteristic ion (m/z 194) as the main boldenone metabolite, the raw data files generated from the screening for anabolic steroids were automatically reprocessed to identify the samples containing sulbutiamine. It was found that of ca. 16 000 samples analyzed in the Russian laboratory during 2009, about 100 samples contained sulbutiamine. It is important to note that most of these samples were collected in-competition, and sulbutiamine concentration was estimated to be greater than 500 ng/ml. This may indicate that sulbutiamine was intentionally administered for its ergogenic and mild stimulating properties.  相似文献   
105.
Diabetes mellitus is a well-recognized cause of male sexual dysfunction and impairments of male fertility. Streptozotocin (STZ) is used for medical treatment of neoplastic islet β-cells of pancreas and producing of animal model of diabetes mellitus type 1 that is characterized by suppression of reproductive activity due to the hyperglycaemia-induced oxidative stress and histopathological alterations in testes. Seeking for the agents that could alleviate diabetes-induced damage to reproductive system is yet the important area of inquiry. The present study was designed to evaluate whether hydrated C60 fullerene (C60HyFn), which is known to be powerful bioantioxidant, eliminate testicular dysfunction induced by STZ-diabetes in rats. Wistar strain male albino rats were divided into four groups of six animals each: (1) control group, (2) C60HyFn-treated nondiabetic group, (3) STZ-diabetic group and (4) C60HyFn-treated diabetic group. Once hyperglycaemia was induced by STZ, rats in the second and fourth groups were treated with C60HyFn (in the form of drinking water) at the dose of 4 μg/kg daily for 5 weeks. In diabetic rats, relative weights of right cauda epididymis, seminal vesicles, prostate, sperm motility and epididymal sperm concentration were significantly less than those of control group, but which were restored in the fourth group treated with C60HyFn (p < 0.001). In hematoxylin and eosin staining, marked histopathological changes including degeneration, desquamation, disorganisation and reduction in germinal cells, interstitial oedema and congestion were evident in the testis of diabetic rats, but C60HyFn treatment resulted in recovery of histopathological changes and an increase in Johnsen's testicular score significantly (p < 0.001). C60HyFn treatment restores the increased apoptosis induced by STZ-diabetes. In diabetic rats, levels of serum testosterone, testicular reduced glutathione (GSH) and alpha-tocopherol were significantly reduced and testicular lipid peroxidation level was increased (p < 0.001). Nevertheless, treatment of diabetic rats with C60HyFn resulted in significant corrective effects on these parameters towards the control levels. C60HyFn, applied alone, did not exert any toxic effects in testicular tissues. Furthermore, C60HyFn treatment in diabetic and nondiabetic rats resulted in considerable elevations of some important polyunsaturated fatty acids. In conclusion, we have presented for the first time substantial evidence that administration of C60HyFn significantly reduces diabetes-induced oxidative stress and associated complications such as testicular dysfunction and spermatogenic disruption.  相似文献   
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BACKGROUND: The co-operation between psychiatrists in Norway and Russia is increasing. The object of this study was to find out whether there were differences in diagnostic practice of psychiatrists in both countries, to look at the nature of the differences and to examine whether these differences affected diagnostic quality. METHOD: Thirty medical doctors working at psychiatric hospitals in both countries diagnosed 12 clinical case vignettes selected from a wide spectre of psychiatric disorders. RESULTS: The Russian clinicians used a larger range of diagnoses than the Norwegians. The Russians tended to diagnose schizophrenia and schizophrenia-like disorders in cases that presented psychotic syndromes, and somatoform disorders in cases that presented agoraphobia. The Norwegians tended to evaluate affective aspects in preference to psychotic symptoms in the case of schizoaffective disorder and overestimate the degree of depression. In general, the Russians had lower total score of correct answers than the Norwegians. CONCLUSION: In spite of the limitations due to minor differences in the data collection phase in the two countries, the study clearly demonstrates differences in diagnostic practice between the countries.  相似文献   
108.
109.
Lung cancer, chronic obstructive pulmonary disease (COPD), and coronary artery disease (CAD) are expected to cause most deaths by 2050. State-of-the-art computed tomography (CT) allows early detection of lung cancer and simultaneous evaluation of imaging biomarkers for the early stages of COPD, based on pulmonary density and bronchial wall thickness, and of CAD, based on the coronary artery calcium score (CACS), at low radiation dose. To determine cut-off values for positive tests for elevated risk and presence of disease is one of the major tasks before considering implementation of CT screening in a general population. The ImaLife (Imaging in Lifelines) study, embedded in the Lifelines study, is designed to establish the reference values of the imaging biomarkers for the big three diseases in a well-defined general population aged 45 years and older. In total, 12,000 participants will undergo CACS and chest acquisitions with latest CT technology. The estimated percentage of individuals with lung nodules needing further workup is around 1–2%. Given the around 10% prevalence of COPD and CAD in the general population, the expected number of COPD and CAD is around 1000 each. So far, nearly 4000 participants have been included. The ImaLife study will allow differentiation between normal aging of the pulmonary and cardiovascular system and early stages of the big three diseases based on low-dose CT imaging. This information can be finally integrated into personalized precision health strategies in the general population.  相似文献   
110.
During the period 1996-1997, three highly homogeneous variants of HIV-1 were identified, circulating among injecting drug users (IDUs) in the former Soviet Union republics. One of these belonged to HIV-1 genetic subtype A (IDU-A), another belonged to HIV-1 genetic subtype B (IDU-B) and the third was a recombinant between the first two variants (CRF03_AB). However, since 1997, the HIV-1 epidemic has affected an increasing number of geographic regions in Russia. This study was undertaken to survey the prevailing genetic variants and to estimate the current proportions of these three HIV-1 genetic subtypes in Russia. Blood samples were taken in 1999-2003 from 1090 HIV-infected individuals and analysed by gag/env HMA. The IDU-A variant was found to be the majority variant (89.7-100%) in 44 of 45 regions of the Russian Federation studied. The IDU-A variant was also found to spreading rapidly through heterosexual transmission in 1999-2003 (30/34, 88%). CRF03_AB predominates in the Kaliningrad region only (28/29, 96.6%). The IDU-B variant is currently of minor importance in the IDU epidemic but other European subtype B variants predominate among men having sex with men (18/18, 100%). Sequence analysis of the env V3 encoding regions derived from HIV-1 infected individuals in Yekaterinburg (the main centre of the HIV-1 epidemic in Russia in 2002-2003) showed that the IDU-A variant is still highly homogeneous. The mean pairwise nucleotide distance (n = 9) was 2.89 +/- 1.14 (range 1.36-6.14). However, the mean genetic distance between each sequence within the samples collected from the Yekaterinburg IDU-A variant subset and the IDU-A consensus is 2.51 +/- 1.06 (range 1.36-4.66) and considerably higher than in South Russia in 1996 (0.79 +/- 0.51, range 0.38-1.90). The current HIV-1 epidemic in Russia is almost entirely caused by a highly homogeneous A-subtype strain, which will influence vaccine development strategies and must be taken into account in the quality control of molecular tests for the diagnosis of HIV-1.  相似文献   
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