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1.

Background  

Choriocarcinoma is an aggressive neoplasm arising in the body of the uterus. The disease normally spreads to lung and brain.  相似文献   
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Introduction  

Development of cell therapies for repairing the intervertebral disc is limited by the lack of a source of healthy human disc cells. Stem cells, particularly mesenchymal stem cells, are seen as a potential source but differentiation strategies are limited by the lack of specific markers that can distinguish disc cells from articular chondrocytes.  相似文献   
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Eastern cottontail (Sylvilagus floridanus, fam. Leporidae), introduced into Piedmont (Italy) in the 1960s, was studied as carrier of dermatophyte fungi. Of 216 hair samples collected from animals culled between September 1999 and July 2000 in the Province of Alessandria (Piedmont, Italy) during a pest control project, 57 (26.4%) yielded dermatophyte colonies. As two different species of dermatophytes grew from two samples, a total of 59 fungal isolates (26.5%) were obtained. Six dermatophyte species both geophilic (M. gypseum, M. cookei, Trichophyton ajelloi, T. terrestre) and zoophilic (M. canis, T. mentagrophytes) were identified. No sex-related differences were found but season-related differences were observed. The highest prevalence of dermatophyte-positive samples was recorded in May–September, due to the geophilic fungi whose prevalence decreased during colder and increased during warmer months ( p < 0.001). The presence of zoophilic dermatophytes, T. mentagrophytes, commonly associated with rodents, small mammals and lagomorphs and M. canis, usually correlated with domestic environment, did not change the whole year round. As Eastern cottontail has been showed to be a carrier of dermatophytes transmissible to man (M. canis, T. mentagrophytes and M. gypseum), it may represent a source of infection for gamekeepers, hunters and veterinarians.  相似文献   
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Objective

Patients with temporal lobe epilepsy (TLE) with hippocampal sclerosis (HS) have diffuse subtle gray matter (GM) atrophy detectable by MRI quantification analyses. However, it is not clear whether the etiology and seizure frequency are associated with this atrophy. We aimed to evaluate the occurrence of GM atrophy and the influence of seizure frequency in patients with TLE and either normal MRI (TLE-NL) or MRI signs of HS (TLE-HS).

Methods

We evaluated a group of 172 consecutive patients with unilateral TLE-HS or TLE-NL as defined by hippocampal volumetry and signal quantification (122 TLE-HS and 50 TLE-NL) plus a group of 82 healthy individuals. Voxel-based morphometry was performed with VBM8/SPM8 in 3T MRIs. Patients with up to three complex partial seizures and no generalized tonic-clonic seizures in the previous year were considered to have infrequent seizures. Those who did not fulfill these criteria were considered to have frequent seizures.

Results

Patients with TLE-HS had more pronounced GM atrophy, including the ipsilateral mesial temporal structures, temporal lobe, bilateral thalami and pre/post-central gyri. Patients with TLE-NL had more subtle GM atrophy, including the ipsilateral orbitofrontal cortex, bilateral thalami and pre/post-central gyri. Both TLE-HS and TLE-NL showed increased GM volume in the contralateral pons. TLE-HS patients with frequent seizures had more pronounced GM atrophy in extra-temporal regions than TLE-HS with infrequent seizures. Patients with TLE-NL and infrequent seizures had no detectable GM atrophy. In both TLE-HS and TLE-NL, the duration of epilepsy correlated with GM atrophy in extra-hippocampal regions.

Conclusion

Although a diffuse network GM atrophy occurs in both TLE-HS and TLE-NL, this is strikingly more evident in TLE-HS and in patients with frequent seizures. These findings suggest that neocortical atrophy in TLE is related to the ongoing seizures and epilepsy duration, while thalamic atrophy is more probably related to the original epileptogenic process.  相似文献   
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The contribution of nitro compounds to airborne particulate mutagenicity was studied with Salmonella typhimurium strains TA98, TA98NR, TA98/1,8DNP6. The results obtained indicate that nitropyrenes play a minor role in air particulate mutagenicity. Seasonal variations indicate a relatively greater contribution of nitro compounds to the mutagenicity of spring and summer samples. Fractionation of extracts into acidic, neutral and basic components shows that neutral compounds account for about two-thirds of the total mutagenic activity. Attempts to extract mutagens adsorbed onto particulate matter with aqueous media were almost completely negative. No significant mutagenicity was detected in urine and faecal extracts and in plasma samples of Sprague-Dawley rats treated with air particulate extracts at 80 mg/kg either per os or by i.p. injection. Negative results were obtained in the micronucleus test with Swiss mice treated at 200 and 400 mg/kg (twice by i.p. injection). A significant decrease in liver aminopyrine-N-demethylase was observed in Swiss mice injected with air particulate extracts or its basic and neutral fractions. In vitro experiments suggest a direct interaction of test materials with microsomal cytochrome P-450.  相似文献   
9.
Insect proteins have been proposed for human and animal food production. Safeguarding the health status of insects in mass rearing allows to obtain high-quality products and to avoid severe economic losses due to entomopathogens. Therefore, new strategies for preserving insect health must be implemented. Modulation of the insect immune system through the diet is one such strategy. We evaluated gene expression of two antimicrobial peptides (one defensin and one cecropin) in Hermetia illucens (L.) (Diptera: Stratiomyidae) reared on different diets. Analyses were performed on prepupae and 10-day-old larvae reared on cereal- and municipal organic waste-based diets and on only prepupae reared on a cereal-based diet supplemented with sunflower, corn, or soybean oil. The inclusion of sunflower oil at different points in the cereal-based diet was also evaluated. Moreover, diet-driven differences in the inhibitory activity of the hemolymph were tested against Escherichia coli DH5α and Micrococcus yunnanensis HI55 using diffusion assays in solid media. Results showed that a municipal organic waste-based diet produced a significant overexpression of antimicrobial peptides only in prepupae. Inclusion of vegetable oils caused an upregulation of at least one peptide, except for the corn oil. Higher expression of both genes was observed when sunflower oil was added 5 days before pupation. All hemolymph samples showed an inhibitory activity against bacteria colonies. Our results suggest that municipal organic waste-based diet and vegetable oil-added diet may successfully impact the immune system of H. illucens. Such alternatives may also exist for other species of economic interest.  相似文献   
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A previous study conducted in this laboratory revealed a decrease in total cholinesterase (total ChE) in the cerebral cortex, hippocampus and striatum in aged rats (24 months) of various strains, as compared with young animals (3 months). The purpose of the present experiments was to extend the study to other brain areas (hypothalamus, medulla-pons and cerebellum) and to assess whether this decrease was dependent on the reduction of either specific acetylcholinesterase (AChE) or butyrylcholinesterase (BuChE) or both. By using ultracentrifugation on a sucrose gradient, the molecular forms of AChE were evaluated in all the brain areas of young and aged Sprague-Dawley rats. In young rats the regional distribution of total ChE and AChE varied considerably with respect to BuChE. The age-related loss of total ChE was seen in all areas. Although there was a reduction of AChE and, to somewhat lesser extent, of BuChE in the cerebral cortex, hippocampus, striatum, and hypothalamus (but not in the medulla-pons or the cerebellum), the ratio AChE/BuChE was not substantially modified by age. Two molecular forms of AChE, namely G4 (globular tetrameric) and G1 (monomeric), were detected in all the brain areas. Their distribution, expressed as G4/G1 ratio, varied in young rats from about 7.5 for the striatum to about 2.0 for the medulla-pons and cerebellum. The age-related changes consisted in a significant and selective loss of the enzymatic activity of G4 forms in the cerebral cortex, hippocampus, striatum, and hypothalamus, which resulted in a significant decrease of the G4/G1 ratio. No such changes were found in the medullapons or the cerebellum. Since G4 forms have been proposed to be present presynaptically, their age-related loss in those brain areas where acetylcholine plays an important role in neurotransmission may indicate an impairment of presynaptic mechanisms.  相似文献   
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