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Sheep have been used as translational models of human postnatal testicular development. However, the morphometric features of the normal developing testis in sheep embryos have not been previously investigated using stereology. The objective of the present work was to establish normal quantitative parameters for fetal testicular tissue components in sheep, using unbiased design-based stereological methods. Twenty-four sheep embryos were divided into four gestational age groups (9–11, 12–14, 15–17 and 18–20 weeks of gestation) on the basis of the embryos’ crown-rump length. Isotropic, systematic uniform random sections of the left testes were obtained by employing the orientator method. Testicular total volume, the absolute and proportional volumes occupied by the seminiferous tubules and interstitial tissue, as well as the seminiferous tubule length, were estimated using the point-counting system and the unbiased counting frame principle. All the parameters, with the exception of the interstitial tissue's fractional volume, gradually increased along with gestational age, with the maximum increase especially seen in the late fetal stages. The proportional volume of the interstitial tissue, on the other hand, showed a decreasing trend along with increasing gestational age. The absolute volume of the testes, of the seminiferous tubules and of the interstitial tissue, and the length of the seminiferous tubules showed a significant (p< 0.05) positive linear correlation with gestational age. Several similarities were observed with human testicular embryogenesis. The stereological data emerging from the present study might prove useful as basic contribution to the fields of andrology and embryology and stimulate further research in these areas.  相似文献   
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Dysplastic features of erythroid and megakaryocytic lineages were observed in a cat with acute erythroid leukemia. We demonstrated that flow cytometry analysis of the expression of glycophorin A and CD71 by neoplastic cells can be helpful in the diagnosis of this type of feline leukemia.  相似文献   
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Background:LINC-ROR, as a cancer-related lncRNA, has vital roles in stem cell survival, pluripotency, differentiation, and self-renewal in hESCs. However, cancer-related molecular mechanisms, its functional roles, and clinical value of LINC-ROR in GC remain unclear. In this study, we aimed to investigate probable interplay between LINC-ROR with SALL4 stemness regulator and their role with the development of the disease. Methods:The mRNA expression profile of LINC-ROR and SALL4 was assessed in tumoral and adjacent non-cancerous tissues of GC patients, using quantitative real-time PCR. Results:Significant LINC-ROR underexpression and SALL4 overexpression were observed in 55.81% and 75.58% (p < 0.0001) of samples, respectively. The expression of LINC-ROR and SALL4 were significantly correlated with each other (p = 0.044). There was an association between the underexpression of LINC-ROR and sex, stage of tumor progression, tumor type, and location of tumor (p < 0.05), and H. pylori infection with SALL4 expression (p = 0.036). There were also significant correlations between concomitant mRNA expression of SALL4 and LINC-ROR in tumors located at distal noncardiac, positive for H. pylori infection, tumors with invasion into the muscle layer of the stomach, and grade II tumor (p < 0.05). Conclusion:The clinical results of the SALL4-LINC-ROR association propose a probable functional interaction between these markers in tumor maintenance and aggressiveness. Our study can help to understand one of the mechanisms involved in the progression of GC through the function of these regulators. Key Words: LINC-ROR, Non-coding RNA, SALL4  相似文献   
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The physiological basis of genetic variation in drought response and its association with yield and related indices is not clear in tall fescue. In this study thirty genotypes of tall fescue (Festuca arundinacea Schreb.) were sampled from a polycross population and evaluated under two levels of irrigation in 2010 (normal and intense stress) and 2011 (normal and mild stress). Physiological traits including relative water content (RWC), total chlorophyll (TChl), chlorophyll a (Chla), chlorophyll b (Chlb), Chla/Chlb, carotenoids (Car), TChl/Car and proline content along with forage yield, agro-morpholgical traits and selection indices (stress tolerance index, STI and drought susceptibility index, DSI) were studied. Large variation and moderate to high heritability was estimated for most of the studied traits. Intense drought condition decreased chlorophyll content while mild stress significantly increased it. In the other hand intense drought stress increased Chla/b while mild stress didn’t change it. Under mild drought stress condition STI was positively correlated with RWC while under intense drought stress condition STI was positively correlated with chlorophyll content. Although proline content was significantly increased in both intense and mild drought stress conditions, no relationship was found between proline accumulation with forage yield and STI. Applications of principle component analysis for screening suitable genotypes are also discussed.  相似文献   
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Background: Rheumatoid arthritis (RA) is a chronic inflammatory disease with many genetic factors predisposing to disease susceptibility. The aim of the present study was to investigate the impact of CD226 rs727088 and rs763361 polymorphisms and susceptibility to RA in a sample of the Iranian population. Methods: This case-control study was carried out on 100 patients with RA and 104 healthy subjects. The polymorphisms were determined using tetra amplification refractory mutation system-polymerase chain reaction assay. Results: The rs763361 (Gly307Ser) polymorphism increased the risk of RA in codominant, dominant and recessive-tested inheritance models (odds ratio [OR] = 3.18, 95% confidence intervals [95% CI] = 1.44-7.02, P = 0.004, CC vs. TT, and OR = 1.98, 95% CI = 1.10-3.57, P = 0.023, CC vs. CT-TT, and OR = 2.61, 95% CI = 1.26-5.37, P = 0.010, CC + CT vs. TT, respectively). In addition, the rs763361 T allele increased the risk of RA (OR = 2.06, 95% CI = 1.38-3.08, P<0.001). However, no significant difference was observed among the groups regarding CD226 rs727088 polymorphism (χ2 = 3.20, P = 0.202). Conclusions: Our finding showed that CD226 rs763361, but not rs727088, gene polymorphism increased the risk of RA in a sample of the Iranian population.Key Words: Rheumatoid arthritis (RA), CD226, Polymorphism  相似文献   
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The improvement of sugar-related factors is associated with root traits in sugar beet. The objectives of the present study were to assess variations of sugar- and root yield (RY)-related traits and to estimate general (GCA) and specific (SCA) combining abilities of several lines, testers and hybrids under various environmental conditions. A line × tester mating design was used to develop 28 hybrids from seven lines × four testers. Presently, root- and sugar-related traits were recorded in parental lines, hybrids and five local ('Pars', 'Torbat' and 'Ekbatan') and international ('Kermit' and 'Tous') check varieties in the eight combinations of location and growing season. Mean RY and sugar yield (SY) were 44.81 t/ha and 7.57 t/ha, respectively. Genotypes tested had 16.91% sugar content (SC) and 13.64% white sugar content (WSC) across trials. No one genotype was found to have high levels for all traits, but several had above mean sugar-related or RY traits. L7T2 as the best hybrid for RY and SY yielded 37.0% and 34.4% more than the checks’ mean, whereas ratios for the best hybrid (L7T4) for SC and WSC were 8.2% and 4.3%, respectively. Additive variance was significant for all traits, whereas dominance component was only significant for RY. Several parental lines had stable GCA effects with respect to direction and magnitude for WSC, RY and SC in environments. L7 and T2 for RY and SY and L3 and T4 for SC and WSC were identified as the best combiners with high GCA effects, and their use might increase favourable alleles in further breeding programmes for traits tested. Estimated heritability for the combined environments was lower for sugar-related traits (54.01%–59.39%) compared with those for RY traits (73.68%–74.21%). Overall, given heritability and additive variances estimated the identification of environmentally stable GCA and SCA effects and might help to increase efficiency of selection of superior cultivars with respect to sugar traits.  相似文献   
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