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81.
We evaluated the effects of variations in atrazine input on the evolution of a bacterial culture adapted to a low atrazine concentration. This initial culture (M3-K) was subjected to weekly subculturing in the presence of a high concentration of atrazine as the only N source (100 mg l−1). After four subculturing, M3-K evolved to a new bacterial culture (M3) which exhibited a significant increase in the extent of atrazine mineralization in comparison with the initial culture. Molecular analyses of M3-K and M3 cultures by cloning, restriction analysis, and sequencing of the 16S rRNA genes revealed significant differences in culture structure and composition. M3-K culture comprised mainly Actinobacteria (40%), β-Proteobacteria (26%), and Bacteroidetes (16%). After exposure to a high atrazine concentration, the dominance of Actinobacteria decreased (14%), Bacteroidetes increased (27%), and β-Proteobacteria were replaced by γ-Proteobacteria (32%). Quantitative PCR revealed that the abundance of atzB and atzC genes relative to total bacteria decreased by a factor of 3–4 following the increase in atrazine concentration, while the relative abundance of trzD increased significantly (≈400 times). Presented study shows that variations in atrazine input drive both functional and compositional shifts in the atrazine-degrading bacterial culture.  相似文献   
82.
Incidence rate of cutaneous malignant melanoma (MM), one of the most aggressive skin tumours, is increasing nowadays. Etiology of MM has not been fully understood. Various etiological factors are of relevance for the occurrence of the disease. The solar radiation as well as long term exposure to ultraviolet radiation has the greatest impact on development of this skin tumour. Melanoma risk factors have different associations with melanoma on body sites. This study investigates the epidemiological and clinical characteristics of MM such as age, gender, distribution of MM on the body and type of melanoma in the area of West Herzegovina, on the sample of 205 patients. It presents the occurrence of MM in the period from 1997. to 2010. Both, females and males have increased the risk of melanoma on the trunk (45.9%). Different body sites receive various amounts of sun exposure, yet melanomas occur on all parts of the body. This may represent different pathways in the etiology of melanoma based on body location. The most frequent type of MM was superficial spreading melanoma (SSM) 47.8%. According to our investigation incidence rate was 18.6% (per 1000 patients).  相似文献   
83.
Morphological analysis of four populations of Suaeda maritima was undertaken in order to examine the variation between populations from inland and maritime saline area, as well as between the two subspecies. Variability and significance of morpho-anatomical differentiation were examined using principal component analysis (PCA), discriminant component analysis (DCA) and cluster analysis. Plants of each population exhibited halomorphic and xeromorphic characteristics. The results of PCA and DCA showed that S. maritima subsp. prostrata and S. maritima subsp. maritima could be clearly separated based on their quantitative anatomical characteristics. Based on our analysis, climate and the amount of salt and ions in the soil, are important factors that enhance the adaptive potential of S. maritima.  相似文献   
84.
There are some reports that low doses of γ-irradiation could induce antioxidant activities in plant material, including soybean. Irradiation, required for the inactivation of some pathogens and induction of mutations, may have adverse effects on sensorial, nutritional and antioxidant qualities. The effects of different γ-irradiation doses (100–200 Gy) on antioxidant properties of soybean seeds was investigated. In this study, we report the results obtained by analysis of antioxidant enzyme activities, reduced glutathione, malonyldialdehyde (MDA) and hydroxyl (HO) radical quantities, soluble protein content, and total antioxidant activity in irradiated soybean seeds. Antioxidant enzyme activities were affected due to high irradiation intensity. Significant changes of total antioxidant activity and MDA and HO.quantities were observed only under the highest irradiation dose, with a 15.7% reduction in total antioxidant activity, MDA quantity increase of 21.6%, and HO radical quantity increase of 79.3% compared to the non-irradiated control. The total soluble protein content increased slightly.  相似文献   
85.
MutS plays a critical role in DNA mismatch repair in Escherichia coli by binding to mismatches and initiating repair in an ATP-dependent manner. Mutational analysis of a highly conserved glutamate, Glu38, has revealed its role in mismatch recognition by enabling MutS to discriminate between homoduplex and mismatched DNA. Crystal structures of MutS have shown that Glu38 forms a hydrogen bond to one of the mismatched bases. In this study, we have analyzed the crystal structures, DNA binding and the response to ATP binding of three Glu38 mutants. While confirming the role of the negative charge in initial discrimination, we show that in vivo mismatch repair can proceed even when discrimination is low. We demonstrate that the formation of a hydrogen bond by residue 38 to the mismatched base authorizes repair by inducing intramolecular signaling, which results in the inhibition of rapid hydrolysis of distally bound ATP. This allows formation of the stable MutS-ATP-DNA clamp, a key intermediate in triggering downstream repair events.  相似文献   
86.
Folic acid and folates have an important role in prevention of neural tube defect that appears in the first weeks of pregnancy, when women are still not aware of their pregnancy, especially when pregnancy is not planned. Since ensuring sufficient quantities of folates and folic acid in this period is essential, dietary habits of childbearing age women are very important. In line with that the intake of folates and folic acid in nutrition of women age group 20-30 years is examined, as well as the frequency of consumption of foodstuffs rich in vitamins and folic acid supplements. Values of folates in serum are presented, dependent on their nutritional habits. Obtained results indicate that in spite of inadequate intake of folates and folic acid from foodstuffs, clinical deficit is not recorded, which is the result of frequent consumption of dietary supplements. In accordance with these dietary habits, differences in the folates status of examinees were observed.  相似文献   
87.
The study investigated differences in morphological, motor and functional abilities between folk and ballet dancers. The sample comprised 51 female subjects: Croatian National Ballet (N=30) and Croatian National Folk Ensemble "LADO" (N=21). The data regarding menstrual cycle, menarche, number of births and smoking habit were collected and the morphological, motor and functional abilities measured. Significant correlations between the amount of fat tissue and number of births were found in both groups. Folk dancers were as tall as ballet dancers but weighted more and had a larger body frame (p<0.001). Ballet dancers were more flexible but there were no differences in absolute maximal oxygen uptake (2.65 vs. 2.35 L/min, p=0.101). Still, as the ballet dancers weighted less, their relative maximal oxygen uptake was significantly higher (37.62 vs. 50.22 mL/kg/min, p<0.001). Also, a high number of 45% of smokers among professional ballet and professional folk dancers was found.  相似文献   
88.
This investigation reports on weed-bed invertebrate abundance associated with the submersed macrophyte Ceratophyllum demersum L. in Lake Sakadaš within Kopački rit Nature Park (Croatia). Twenty five taxonomic groups, with the dominance of chironomids (79%), were recorded at three stations during the investigation from July 14 to September 8, 2004. Nematodes and large predatory larvae of Zygoptera with 6% were second in dominance, followed by oligochaetes with 5%. Weed-bed invertebrates on C. demersum were more abundant than on Myriophyllum spicatum L. due to different morphology of the host plants. Environmental parameters within C. demersum stands were found in the same range at all stations, but they changed during the season. They indicated eutrophy with the tendency to hypertrophy which is reflected by the composition of the weed-bed invertebrate community.  相似文献   
89.
High levels of expression of galectin-1 and galectin-3, the beta-galactoside-binding proteins, have been recently described in malignant thyroid tumors but not in adenomas nor in normal thyroid tissue. However, there are no data about the expression of these galectins during fetal thyroid development. In this study we analyzed immunohistochemically the presence of galectin-1 and galectin-3 in human fetal thyroid glands (16-37 weeks of gestation). Weak to moderate cytoplasmic staining for galectin-1 was observed in follicular cells of all fetal thyroids. Galectin-3 could not be detected in thyroid follicular cells of any fetal thyroid investigated. Both galectins were detected in stromal tissue, but staining for galectin-1 was more intense. The absence of galectin-3 in thyroid cells during fetal development suggests that galectin-3 is expressed de novo during malignant transformation of thyroid epithelium, and that galectin-1 could be considered an oncofetal antigen. The results obtained indicated potential roles for galectin-1 and galectin-3 during the investigated period of human fetal thyroid gland development. Both galectins might participate in developmental processes regarding stromal fetal thyroid tissue organization, whereas galectin-1 might have a function in thyroid epithelium maturation.  相似文献   
90.
The aim of this investigation was to establish precise indicators of the vertical dimension of occlusion (VDO) which could be used as objective parameters in prosthodontic treatment providing exact control of the reconstructed vertical dimension of occlusion, early detection of errors and correction of the vertical dimension of occlusion during complete denture manufacturing. A total of 60 lateral cephalometric radiographs of subjects with natural dentition and class I skeletal jaw relationship, of Serbian nationality from the region of Vojvodina, were included in the investigation. Thirty subjects were males, and thirty females, their age range was 20 to 29 years. Cephalometric analysis was performed by using "Dr. Ceph" computer software (FYI Technologies, GA, USA). By evaluation of the craniofacial complex in subjects with natural dentition, horizontal dentofacial developmental growth was established in the examined sample and it was based on the relationship between the posterior and anterior total facial height (S-Go:N-Me, female X=68.96%, male X=72.8%) and statistically significant differences were found between the sexes in almost all linear dimensions and in the relation between the posterior and the anterior total facial height. Highly significant differences (p<0.001) between the sexes were found in regard to anterior total facial height (N-Me, male X=120.75 mm, female X=112.72 mm) and the anterior lower facial height (ANS-Me, male X=67.87 mm, female X=61.50 mm) (p<0.05). The proportions of the upper and lower anterior facial heights (N-ANS:ANS-Me, male X=79.36%, female X=80.63%) were within normal values in both sexes. Facial harmony existed both in men and women. Cephalometric study of the subjects with complete natural dentition included in this study provided important and specific parameters for optimal reconstruction of vertical dimension of occlusion in the treatment of edentulous patients.  相似文献   
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