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1.
Mixed convection peristaltic flow of Jeffrey nanofluid in a channel with compliant walls is addressed here. The present investigation includes the viscous dissipation, thermal radiation and Joule heating. Whole analysis is performed for velocity, thermal and concentration slip conditions. Related problems through long wavelength and low Reynolds number are examined for stream function, temperature and concentration. Impacts of thermal radiation, Hartman number, Brownian motion parameter, thermophoresis, Joule heating and slip parameters are explored in detail. Clearly temperature is a decreasing function of Hartman number and radiation parameter.  相似文献   
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Molecular Biology Reports - A recent spike in demand for chemical preservative free food has derived the scientific community to develop natural ways of food preservation. Therefore,...  相似文献   
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Abstract

A total of 106 Fusarium spp. were isolated from infected roots and soil samples of wheat and rice. Of the 106 isolates, 32 from wheat, and 74 from rice, were isolated. Six Fusarium spp. (F. oxysporum, F. moniliforme, F. poae, F. graminearum, F. tricinctum and F. equiseti) were identified at specie level. In aggressiveness tests Fusarium spp. root rot causing fungi were screened out into different aggressiveness classes according to disease severity scales. The aggressiveness of Fusarium spp. was studied on wheat varieties (Inqalab-91 and chakwal-86) and on rice varieties (Basmati-385 and IRRI-6) under controlled conditions. The overall total number of aggressive isolates was higher in rice than in wheat. However, the percentage of severely aggressive isolates was high in wheat, whereas the percentage of moderately and slightly aggressiveness isolates was high in rice. In rice, five isolates were non-aggressive and on wheat 17 were non-aggressive. Random Amplified Polymorphism DNAs (RAPDs) were used to study the polymorphism and genetic variations within the population of Fusarium spp. that established to study correlation between taxonomical and genetical characters of fungi. Five random primers were used P1 (5′-AGGAGGACCC-3′), P2 (5′-ACGAGGGACT-3′), PE7 (5′-AGATGCAGCC-3′), P14 (5′-CCACAGCACG-3′) and PE20 (5′-AACGGTGACC-3′). Each of the 10-mer primers produced results based on the respective banding patterns they generated in present investigations. Primers distinguished the F. oxysporum, F. moniliforme, F. graminearum, F. tricinctum, F. poa and F. equiseti. All the tested primers yielded amplification products, and that were reproducible. Although there was some intraspecific variation with primers, some strains were similar and some were different in banding pattern. In F. oxysporum, F. moniliforme, F. graminearum, F. tricinctum, F. poa and F. equiseti were seen clustered close to one another but each primer separated them unambiguously. All primer (P1, P2, P14, PE7 and PE20) combination produced 62 bands. All primers have shown interspecific and intraspecific variations in banding patterns.  相似文献   
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NtdA from Bacillus subtilis is a sugar aminotransferase that catalyzes the pyridoxal phosphate-dependent equatorial transamination of 3-oxo-α-d-glucose 6-phosphate to form α-d-kanosamine 6-phosphate. The crystal structure of NtdA shows that NtdA shares the common aspartate aminotransferase fold (Type 1) with residues from both monomers forming the active site. The crystal structures of NtdA alone, co-crystallized with the product α-d-kanosamine 6-phosphate, and incubated with the amine donor glutamate reveal three key structures in the mechanistic pathway of NtdA. The structure of NtdA alone reveals the internal aldimine form of NtdA with the cofactor pyridoxal phosphate covalently attached to Lys-247. The addition of glutamate results in formation of pyridoxamine phosphate. Co-crystallization with kanosamine 6-phosphate results in the formation of the external aldimine. Only α-d-kanosamine 6-phosphate is observed in the active site of NtdA, not the β-anomer. A comparison of the structure and sequence of NtdA with other sugar aminotransferases enables us to propose that the VIβ family of aminotransferases should be divided into subfamilies based on the catalytic lysine motif.  相似文献   
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BackgroundSeveral developing countries like Pakistan step into Sustainable Development Goals period with crucial maternal and child health needs that need to be addressed for improving health outcomes among people. We aim to explore existent socio-economic disparities in use of family planning methods (FPM) among Pakistani women, and compare any such inequalities between the years 2006 and 2013.SettingPakistan Demographic and Health Surveys (PDHS) 2006–7 (n = 9177) and the most recent 2012–13(n = 13558) data were used to conduct secondary analysis. Participants were ever married women aged between 15 and 49 years. Socio-economic status was assessed by the education level and wealth index. Inequalities were measured through Odds Ratio (OR), Relative Index of inequality (RII), and Slope index of inequality (SII) on non-use of FPM.ResultsAlthough the prevalence of FPM use has increased over time (28% in 2006 versus 54% in 2013), the socio-economic inequalities persistently exist. Comparing results of PDHS 2006 with PDHS 2013, education related absolute inequalities among urban dwellers increased from -0.41 (95% CI -0.67, -0.13, p-value < 0.01) to -0.83 (95% CI -1.02, -0.63, p-value < 0.01); and increased from -0.93 (95% CI -1.21, -0.64, p-value < 0.01) to -0.98 (95% CI -1.20, -0.76, p-value < 0.01) among rural dwellers. Similarly wealth related absolute inequalities are also existent.ConclusionsAlthough the FPM use has increased over time, but it is important to note that socio-economic gap in use of FPM persists. Such differences have disadvantaged the poor and the illiterate. Family planning programs may target the disadvantaged subgroups for ensuring well-being of women and children in Pakistan.  相似文献   
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Postharvest losses of cut flowers is one of the considerable challenges restricting their efficient marketability. Consequently, such challenges have triggered a constant hunt for developing compatible postharvest treatments to mitigate postharvest losses. Interestingly, recent studies entrench extensive role of salicylic acid (SA) in mitigating postharvest losses in various flower systems. The current investigation focusses on role of SA in augmenting physiological and biochemical responses to mitigate postharvest senescence in cut spikes of Consolida ajacis. The cut spikes of C. ajacis were supplemented with various SA treatments viz, 2 mM, 4 mM, 6 mM. The effects of these treatments were evaluated against control set of spikes placed in distilled water. Our study indicates considerable increment in postharvest longevity of cut spikes, besides an increase in solution uptake, sugar and protein content of tepal tissues.SA augmented antioxidant system via upsurge in phenolic content and antioxidant enzymes viz, superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) to forfend reactive oxygen species (ROS) related oxidative damage. SA profoundly reduced lipoxygenase (LOX) activity to preserve the membrane integrity and thus prevented seepage of solutes from tepal tissues. These results authenticate SA particularly 4 mM concentration as effective postharvest treatment to preserve the postharvest quality of C. ajacis cut spikes.  相似文献   
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We investigated prostanoid biogenesis by human colonic fibroblasts (CCD-18Co cells and nine primary fibroblast cultures) exposed to a primary (cholic, CA) or a secondary (deoxycholic, DCA) bile acid. Basal PGE2 levels in CCD-18Co cultures and fibroblast strains initiated from normal and adenocarcinomatous colon, respectively, were 1.7 +/- 0.3, 4.0 +/- 2.0, and 15.0 +/- 4.8 ng/mg protein. Peak levels 24 h after exposure to DCA (300 microM) rose, respectively, seven-, six- and sevenfold, but CA elicited no such responses. Increases in PGE2 synthesis were preceded by sequential increases in PGH synthase-2 mRNA and protein expression and were fully prevented by a nonselective (indomethacin) or a selective (celecoxib) nonsteroidal anti-inflammatory drug. DCA, but not CA, caused abrupt, transient increases in fibroblast intracellular Ca2+ concentration ([Ca2+]i) approximately 1 min after exposure. Increased [Ca2+]i was required for DCA-mediated induction of PGE2 synthesis, and protein kinase C was a further essential component of this signaling pathway. Colonic fibroblasts may be a major target for prostanoid biogenesis induced by fecal bile acids and, potentially, other noxious actions of these agents.  相似文献   
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The effect of various doses of sodium tellurite (0.4, 0.8, and 2.0 mg/kg body weight, orally) on the activity of antioxidant enzymes (glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and catalase) and content of glutathione and thiobarbituric acid reactive substances (TBARSs) in the cerebrum, cerebellum, and brainstem of male albino mice was studied after 15 d of treatment. All of the doses of tellurium (0.4, 0.8, and 2.0 mg/kg body weight, orally) have depleted the activity of antioxidant enzymes and the content of glutathione dose dependently in the cerebrum, cerebellum, and brainstem and it was significant with the dose of 2.0 mg/kg. On the other hand, the 2.0-mg/kg dose of tellurium has significantly elevated the content of TBARSs in the cerebrum and cerebellum. The 0.8-mg/kg dose of tellurium has significantly depleted the activities of glutathione peroxidase in the cerebrum and brainstem, glutathione-S-transferase in the cerebrum and cerebellum, catalase in the brainstem, and the content of glutathione in the cerebrum and cerebellum. In contrast, this dose has significantly elevated the content of TBARSs in the cerebrum and cerebellum. However, the depletion in the activity of glutathione reductase with various doses of sodium tellurite was not significant in any brain part of mice. The result suggests that sodium tellurite differentially affects the antioxidant status within various parts of the mice brain.  相似文献   
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A number of substrates were tested for the cultivation of microorganisms to produce a host of enzymes. The effect of different substrates (wheat and rice straw, sugar cane waste, wood waste), incubation temperatures (20–40°C), initial pH levels (3.5–9.0), incubation periods (0–72 hours) and nitrogen sources (ammonium sulfate, urea, peptone, yeast extract, sodium nitrate) on growth and α-amylase activity was studied for the native and mutant strains. Maximum enzyme activity was observed at 1.5% wheat straw for Aspergillus niger FCBP-198 and An-Ch-4.7 and at 2% wheat straw for An-UV-5.6, with sodium nitrate as a principle nitrogen source. The optimum temperature for maximum enzyme activity was 30°C for the parental strain, while An-UV-5.6 and An-Ch-4.7 thrived well at 32.5°C. The best conditions of pH and incubation duration were 4.5 and 48 hours, respectively, for all the strains. Mass production under preoptimized growth conditions demonstrated the suitability of wheat straw for swift mycelial colonization and viability.  相似文献   
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