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161.
The aim of this study was to determine the immunohistochemical expression and localization of insulin-like growth factor-I (IGF-I), transforming growth factor-β2 (TGF-β2), basic fibroblast growth factor (bFGF) and epidermal growth factor-receptor (EGF-R) in developing rat ovaries.Eighteen female Wistar rats were enrolled in this study; newborn (n = 6), one-month-old (n = 6) and adult (n = 6) rats. Formalin-fixed and parafin-embedded ovarian tissues were stained with antibodies against IGF-I, TGF-β2, bFGF and EGF-R, immunohistochemically. The ovarian cells were evaluated by semi-quantitative scoring system under light microscope.The staining of IGF-I, TGF-β2, bFGF and EGF-R were most intense in the oocytes and were heavily at one-month-old rats. A moderate immunostaining in theca cells and corpus luteii reacted with IGF-I in adult rats. Furthermore the staining intensity for IGF-I was moderate in granulosa cells of newborn rat ovaries. We detected also a moderate staining for TGF-β2 in corpus luteii of adult rats. In addition, we found a bFGF immunostaining mainly in oocytes of follicles of young and adult rats. Immunostaining for EGF-R was moderate in granulosa cells of one-month-old rats.In conclusion, this study suggests that growth factors play a pivotal role in ovarian function, especially in follicular development. The role of growth factor in controlling degeneration or growth (or both) of ovary follicles remain as explained.  相似文献   
162.
Meiofauna are known to live on hard substrates in association with periphytic and epiphytic algae and attached epibiota; however, the abundance, diversity and colonizing abilities of hard-substrate meiofauna have been poorly documented. We quantified meiofauna living on microalgal-covered pilings associated with a wood pier in a shallow (<2 m deep) estuarine embayment with the use of a suction sampler, and compared colonization of pier-piling and sediment-dwelling meiofauna onto collectors that capture suspended meiofauna from the water column. Collectors were small mesh pads (159 cm3) suspended at mid-water depth, and their size and structural complexity were similar to floating or drifting masses of macroalgae that may be colonized by meiofauna. Sediment was collected by coring, and copepod (to species) and nematode (to genera) colonists on mesh pads were compared with pier-piling and sediment communities. Abundance of total meiofauna averaged 124±13.6 (S.E.) on pier pilings, compared to 2092±274.6 individuals 10 cm−2 in surrounding sediment. Phytal copepods (free-living copepods with prehensile first legs and dorsoventrally and laterally compressed body forms) and copepod nauplii dominated pier-piling collections, but nematodes were dominant on faunal collectors and in sediment. Phytal copepods also were abundant on faunal collectors but were rare in sediments. Copepod and nematode diversities were similar, but species composition was largely nonoverlapping, in pier pilings and sediments. Net recruitment of meiofauna to faunal collectors averaged about 900 individuals collector−1 day−1 during the 1-week experiment. Nematode and copepod colonists on faunal collectors were both much more similar to pier-piling than to sediment assemblages. These data suggest that meiofauna are abundant and diverse on algal-covered pier pilings, and they may become more important to marine ecology as artificial hard substrates increase with increasing urbanization. Furthermore, pier-piling meiofauna appear to readily migrate into the water column and probably contribute to a rapidly dispersing pool of meiofauna in estuaries.  相似文献   
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Liver and colon pro- and anti-oxidant enzyme activities were investigated in rats treated with ethylnitrosourea (ENU) (i.p.) (4 mg/kg body wt) for 6 months. The pro-oxidant enzymes (NADPH cytochrome c reductase, NADH cytochrome c reductase, NADH cytochrome b5 reductase and cytochrome P-4502E1and the antioxidant enzyme, superoxide dismutase (SOD) exhibited significantly increased activity in liver and colon. Glucose-6-phosphate dehydrogenase (G6PDH) and glutathione-S-transferase (GST) showed enhanced activity in liver, but decreased activity in colon. Glutathione peroxidase (GP) and glutathione reductase (GR) activities were significantly increased in colon, but decreased in liver. Catalase (CAT) activity while showed a significant increase in liver, exhibited only marginal increase in colon. Malondialdehyde (MDA) level was significantly elevated in both tissues.  相似文献   
165.
Gender differences in fat patterning in children living in Ankara   总被引:3,自引:0,他引:3  
Body composition is an excellent indicator for assessing obesity and nutritional status of both individuals and populations. Youth obesity has important health and social implications, because a large proportion of adult obesity has its origin in childhood. Numerous studies report that adverse levels of cardiovascular diseases risk factors are associated with adiposity in children. Concerning the Turkish population there is up to now only limited information with regard to adiposity in children. The aim of this study was therefore to determine the anthropometric and body composition characteristics and to investigate sex differences in fat patterning including fat distribution in a group of children living in Ankara. The present study evaluated the body composition of 332 boys and 269 girls aged between 8 and 11 years, attending public schools. It was carried out by a cross-sectional study and was focused on that anthropometric variables, which reflect body fat and fat-free mass. Anthropometric measurements including height, weight, triceps and subscapular skinfolds thickness were carried out on these children. The body mass index (BMI) was also calculated. The measurements were used to estimate the two-compartment model of body composition: fat-free mass (FFM) and body fat (BF) from skinfold equations. The mean fat percentage in boys is highest at 11 years (16.8%) and lowest at 10 years (15.6%). In girls these figures come to 18.2% and 17.1%, respectively. Girls of these age groups have a significantly larger percentage of body fat and skinfold thickness. At this young age there is therefore clear evidence of sexual dimorphism in fat patterning, as girls are showing a greater subcutaneous adiposity, which is mainly contributed by the triceps fat. The body fat (kg) increases in both sexes all over the investigated age groups. The Pearson correlation matrix showed a high significant relation between the anthropometric measurements (p < 0.01). The present study confirms the findings that sexual dimorphism of fat patterning in children is to be seen in the age of 8 - 11 years. It furthermore presents basic data of body composition, which could serve as reference data in other studies on the Turkish population.  相似文献   
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Familial Mediterranean fever (FMF) is the most frequent hereditary inflammatory disease. FMF causes different clinical manifestations in different ethnic groups and countries. In this study, we retrospectively reviewed the records of 1,152 FMF suspected patients (673 female and 479 male) from November 2006 to December 2010. A commercial kit assay for the identification of MEFV (Mediterranean fever) gene mutations based on PCR and reverse-hybridization was used to investigate 12 mutations of the MEFV gene. 52.17% of 1,152 FMF suspected patients had MEFV mutation and 45.25% of them were male. The rate of MEFV mutation among male and female patients were 56.78 and 48.88%, respectively. These results were statistically significant and might support the suggestion that FMF had much more penetrance in male patients (P = 0.009). Not any significant difference was observed between the male and female patients in terms of heterozygote and homozygote mutation carriage rate (P = 0.071). Also not any significant difference was observed between the male and female patients in terms of compound heterozygote mutation carriage rate (P = 0.058).  相似文献   
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This study aimed to demonstrate the ways in which two chromium species, Cr (III) and Cr (VI), can affect various physiological and biochemical parameters in the plant Ceratophyllum demersum L., and to evaluate the single and combined impact of exposure concentration and duration. C. demersum was exposed to Cr (III) and Cr (VI) at a variety of concentrations (1, 2, 5, and 10 mM) and for differing durations (1, 2, 4, and 7 days), after which Cr accumulation, relative growth rate (RGR), malondialdehyde (MDA) content, electrical conductivity (EC), photosynthetic pigmentation, proline content and antioxidant enzyme activities were examined. The single and combined effects of exposure duration and Cr concentration on each parameter were determined using a two-way analysis of variance. For both the Cr (III) and Cr (VI) applications, it was observed that concentration had a significant effect on all parameters assessed. However, duration had no statistically significant effect on proline content in the Cr (III) application, or on MDA and protein content in the Cr (VI) application. It was determined that concentration exerted greater effects than duration for both Cr species studied. In addition, the results indicated that duration and concentration had a synergistic effect on variations of RGR, EC, protein content, and antioxidant enzyme activities in both the Cr (III) and Cr (VI) applications. These results may be useful when planning further phytoremediation and plant biotechnology studies.  相似文献   
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