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1.
Sandflies are the main vectors of Leishmania parasites in tropical and subtropical areas. The immunization of vertebrate hosts with vector components through repeated bites may offer an alternative method for sandfly control. Aliquots of female Phlebotomus papatasi (Scopoli) (Diptera: Psychodidae) were weekly blood fed on 12 individual hamsters throughout 18 successive weeks. Significant biological and biochemical changes resulting from antibodies developed by immunized host sera against repeated biting were observed in sandfly females. Blood feeding and fertility rates of females significantly gradually declined to the end of the study period. No appreciable difference was observed in mortality rates among flies repeatedly fed on individual hamsters throughout weeks 9 and 18, compared to flies fed on naïve hamsters. Total salivary gland proteins of female sandflies were compared to proteins in sera of sensitized hamsters. SDS-page revealed bands common to both flies and hosts, indicating the development of anti-saliva antibodies in hamster sera. The importance of anti-sandfly saliva antibodies as a potential tool for vector control leading to the interruption of leishmaniasis is discussed.  相似文献   
2.
Ishac  Y. Z.  El-Haddad  M. E.  Daft  M. J.  Ramadan  E. M.  El-Demerdash  M. E. 《Plant and Soil》1986,90(1-3):373-382
Summary The effect of seed inoculation withAzotobacter spp. orAzospirillum spp., and garbage amendment (0.5%), on the growth of wheat was studied in a field experiment under sub-tropical conditions. Two levels of N fertilizer were applied, the usual field rate (150 kg N ha–1) and half this amount. Tillering of plants, dry matter contents and nitrogenase activity were determined 30, 60 and 90 days after sowing. At the end of the experimental period, spore numbers and percentage of mycorrhizal infection were observed in the rhizosphere and root systems of plants. Straw and grain yields were also determined. The results of this study showed that seed inoculation and/or organic amendment stimulated plant growth, nitrogenase activity and mycorrhizal infection. This was more noticeable withAzotobacter than withAzospirillum. Inoculation withAzotobacter together with 1/2 N dose and organic amendment was the most effective application (19.75 and 10.70 t ha–1 were recorded for straw and grain yield, respectively).  相似文献   
3.
The in vitro propagation of medicinal species is proving to be one successful approach to addressing the issues raised by increasing global demand, overharvest of wild populations and variability in product quality. In this report we describe a protocol for establishing nodal cultures of an Egyptian medicinal plant, Echinops spinosis-simus Turra and for the induction of regeneration in epidermal peels and leaf explants obtained from the nodal cultures. Kinetin was found to be optimal for induction and proliferation of nodal cultures. Transverse slices of leaf blades produced regenerants resembling somatic embryos in the presence of thidiazuron while regeneration was observed on epidermal peels only when the medium contained elevated auxin concentrations.  相似文献   
4.
Abstract

Lycopene (LP), a naturally occurring carotenoid in red-coloured fruits, especially tomatoes, has a pivotal role in counteracting the deleterious effect of oxidative stress on periodontal tissues. The aim of this study is to prepare solid lipid microparticles (SLMs) encapsulating LP and to assess their biochemical and clinical effects in the management of chronic periodontitis. Optimization of SLMs was performed by assessing particle size and LP entrapment efficiency. Clinical study included 16 chronic periodontitis patients allocated into two groups, Group I was managed by scaling and root planing (SRP) and local delivery of LP loaded SLMs, while Group II was managed by SRP only. Protein carbonyl (PC) levels as a biomarker of oxidative stress and drug concentration in gingival crevicular fluid (GCF) were assessed at different time intervals. Results revealed that optimum formula of SLMs had a particle size of 77.28 µm and entrapped 98.03% of LP. SLMs recorded 30 d of drug release with no burst effect. Patients treated with LP SLMs showed significantly lower levels of PC after SRP compared to those treated with SRP only, in addition to improvement in the measured clinical parameters. In conclusion, locally delivered LP SLMs along with SRP could have a protective effect over periodontal tissues and it has the ability to decrease oxidative damage of proteins in diseased periodontium.  相似文献   
5.
Recent studies suggest that bone marrow stem cells (BMSCs) are promising grafts to treat a variety of diseases, including reproductive dysfunction. Primary ovarian failure is characterized by amenorrhea and infertility in a normal karyotype female, with an elevated serum level of follicle-stimulating hormone (FSH) and a decrease level of estrogen caused by a mutation in FSH receptor (FSHR) gene. Currently, there is no effective treatment for this condition. The phenotype of FSHR (-/-) mouse, FORKO (follitropin receptor knockout), is a suitable model to study ovarian failure in humans. Female FORKO mice have elevated FSH, decreased estrogen levels, are sterile because of the absence of folliculogenesis, and display thin uteri and small nonfunctional ovaries. In this study, we determined the effects of BMSC transplantation on reproductive physiology in this animal model. Twenty four hours post BMSC transplantation, treated animals showed detectable estroidogeneic changes in daily vaginal smear. Significant increase in total body weight and reproductive organs was observed in treated animals. Hemotoxylin and eosin (H&E) evaluation of the ovaries demonstrated significant increase in both the maturation and the total number of the follicles in treated animals. The FSH dropped to 40-50% and estrogen increased 4-5.5 times in the serum of treated animals compared to controls. The FSHR mRNA was detected in the ovaries of treated animals. Our results show that intravenously injected BMSCs were able to reach the ovaries of FORKO mice, differentiate and express FHSR gene, make FSHR responsive to FSH, resume estrogen hormone production, and restore folliculogenesis.  相似文献   
6.
7.
Abstract. Classification of the vegetation of the Farasān Islands using TWINSPAN technique resulted in the recognition of seven community types associated with seven different habitat types: silty runnels, palm orchards, rocky plains, rocky plateau crevices, coastal sand dunes, sand plains, and mangroves. These communities were dominated or co-dominated by 13 perennial species; 87 associate species were recorded in the study area with chamaephytes dominating the life-form spectrum. Canonical Correspondence Analysis (CCA) indicated that organic carbon, soil moisture, silt, electrical conductivity and calcium carbonate were the major edaphic gradients controlling the distribution of the plant communities on the Farasān Islands. Higher species richness was recorded in the plant communities inhabiting the palm orchards, the crevices of the rocky plateau, silty runnels, rocky plains and rocky plateau, while those of the mangrove and sand formations (dunes and plains) showed a lower species richness. Soil texture and organic matter are the main factors promoting species diversity in the more diversified habitats, while high salinity and calcium carbonate are the main factors associated with lower species diversity in the less diversified habitats of the study area.  相似文献   
8.
Artemisia judaica L., an Egyptian medicinal plant used in the treatment of gastrointestinal disorders, was mass-propagated and grown using solid, paper-bridge-support liquid, liquid-flask and bioreactor cultures. The liquid-flask culture using 50 ml MS liquid medium in 250 ml flask yielded significantly greater shoot proliferation than either solid cultures or paper-bridge-support liquid cultures. Increasing flask capacity from 100 to 500 ml improved shoot proliferation and growth. Mass-propagation efficiencies of various bioreactor systems, viz. temporary immersion reactors and bubble column reactors, were also compared. The temporary immersion bioreactor was found to have significant advantages for A. judaica shoot proliferation. The shoot cultures from the temporary immersion reactor formed complete plantlets when subcultured onto a medium containing 1 micromoll(-1) indole-3-butyric acid (IBA), and mature plants were established, acclimatized and thrived in standard greenhouse conditions. Assays of antioxidant activity and total flavonoid content of in vitro and in vivo grown tissues were evaluated as gross parameters of medicinal efficacy. Significantly higher antioxidant activity and flavonoid contents were observed in the tissues of mature greenhouse-grown plants. The efficient in vitro production systems developed in this study provided sterile, consistent tissues for investigation of bioactivity and germplasm conservation of A. judaica.  相似文献   
9.
Low dose methotrexate is the cornerstone for the treatment of rheumatoid arthritis. One of its major drawbacks is hepatotoxicity, resulting in poor compliance of therapy. Dissatisfied arthritis patients are likely to seek the option of complementary and alternative medicine such as bee venom. The combination of natural products with modern medicine poses the possibility of potential interaction between the two groups and needs investigation. The present study was aimed to investigate the modulatory effect of bee venom acupuncture on efficacy, toxicity, and pharmacokinetics and tissue disposition of methotrexate. Complete Freund''s adjuvant induced arthritic rats were treated for 3 weeks with methotrexate and/or bee venom. Arthritic score, ankle diameter, paw volume and tissue expression of NF-κB and TNF-α were determined to assess anti-arthritic effects, while anti-nociceptive effects were assessed by gait score and thermal hyperalgesia. Methotrexate toxicity was assessed by measuring serum TNF-α, liver enzymes and expression of NF-κB in liver. Combination therapy of bee venom with methotrexate significantly improved arthritic parameters and analgesic effect as compared to methotrexate alone. Bee venom ameliorated serum TNF-α and liver enzymes elevations as well as over expression of NF-κB in liver induced by methotrexate. Histological examination supported the results. And for the first time bee venom acupuncture was approved to increase methotrexate bioavailability with a significant decrease in its elimination. Conclusion: bee venom potentiates the anti-arthritic effects of methotrexate, possibly by increasing its bioavailability. Also, it provides a potent anti-nociceptive effect. Furthermore, bee venom protects against methotrexate induced hepatotoxicity mostly due to its inhibitory effect on TNF-α and NF-κB.  相似文献   
10.
Radiotherapy is a major factor contributing to female infertility by inducing premature ovarian failure (POF). Therefore, the need for an effective radioprotective agent is evident. The present study investigated the mechanism of potential radioprotective effect of sodium selenite on radiation-induced ovarian failure and whether sodium selenite can stimulate in-vivo follicular development in experimental rats. Immature female Sprague-Dawely rats were either exposed to gamma-radiation (3.2 Gy, LD20), once and/or treated with sodium selenite (0.5 mg/kg), once daily for one week before irradiation. Follicular and oocyte development, apoptotic markers, proliferation marker as well as oxidative stress markers were assessed 24-h after irradiation. In addition, fertility assessment was performed after female rats became completely mature at two months of age. Sodium selenite significantly enhanced follicular development as compared to the irradiated group. Sodium selenite significantly reversed the oxidative stress effects of radiation that was evidenced by increasing in lipid peroxide level and decreasing in glutathione level, and glutathione peroxidase (GPx) activity. Assessment of apoptosis and cell proliferation markers revealed that caspase 3 and cytochrome c expressions markedly-increased, whereas, PCNA expression markedly-decreased in the irradiated group; in contrast, sodium selenite treatment prevented these alterations. Histopathological examination further confirmed the radioprotective efficacy of sodium selenite and its in-vivo effect on ovarian follicles’ maturation. In conclusion, sodium selenite showed a radioprotective effect and improved folliculogenesis through increasing ovarian granulosa cells proliferation, estradiol and FSH secretion, and GPx activity, whilst decreasing lipid peroxidation and oxidative stress, leading to inhibition of the apoptosis pathway through decreasing the expressions of caspase 3 and cytochrome c.  相似文献   
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