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41.
Plasmonics - The environmental concerns in the current century is not only limited to the polluting effect of the fossil fuel consumption but also the recycling challenges of waste turns to be a... 相似文献
42.
Plasmonics - In this paper, we have proposed a new npn-type design of a CMOS-compatible metal/semiconductor/insulator/metal (MSIM) plasmonic structure, to be used as a different geometry to... 相似文献
43.
Vascular disease is one of the complicating features of diabetes mellitus. Magnesium deficiency has recently been proposed as a novel factor implicated in the pathogenesis of diabetes complications. Several studies have indicated that hypertension in diabetic patients is an independent altered reaction of blood vessels to neurotransmitters and circulating hormones. Since magnesium has been proposed to decrease vascular sensitivity to vasoconstrictor agents, the present study was designed to determine whether chronic magnesium sulfate administration could prevent vascular complications of STZ-induced diabetes in rats. The animals were divided into six groups: two groups served as controls and received tap water for 8 weeks, while in the other four groups, made diabetic with a single IV injection of 40 mg/kg STZ, two groups treated with magnesium sulfate (10 g/L) added to the drinking water, and the other two groups received tap water only. After 8 weeks, in 3 groups (control, diabetic and Mg-treated), left common carotid artery was cannulated for continuous recording of blood pressure. All animals in these groups were decapitated and blood samples were drawn for glucose, Ca and Mg measurements. In the 3 remaining groups (again divided into control, diabetic and Mg-treated), the mesenteric vascular bed was perfused according to the McGregor method, and descending thoracic aortas were used for measurement of elasticity. In diabetic rats, plasma glucose was significantly increased and plasma magnesium was significantly decreased compared to controls and Mg-treated animals. Although plasma magnesium of Mg-treated animals increased significantly, it failed to reach to the magnesium level of the control group. Ca/Mg ratio was also increased compared to the control and Mg-treated animals. Mean arterial blood pressure in diabetics was significantly higher than control and Mg-treated rats. Similarly, there was a significant difference in mean arterial blood pressure of Mg-treated rats compared to control animals. Baseline perfusion pressure of diabetic group was significantly higher than control and Mg-treated groups with intact and denuded endothelium. Magnesium sulfate treatment decreased mean perfusion pressure of mesenteric vascular bed in intact and denuded endothelium in comparison with non-treated diabetic rats. There was a significant increase in passive tension in the aorta of diabetic rats compared to control and Mg-treated rats. However, there was no significant difference between Mg-treated and control rats. From the results of this study it may be concluded that magnesium could control STZ-induced diabetes and prevent its vascular complications. 相似文献
44.
Growth of Metarhizium anisopliaein modified starch-casein medium produced 61, 50, and 58 mg swainsonine/l when cultured in shaken flasks, stirred-tank and air-lift reactors respectively. Over approximately 45 h, the maximum swain-sonine specific productivity was 0.47 mg/g.h in a stirred tank reactor and 0.32 mg/g.h in an air-lift reactor. After 120 h, increasing broth viscosity was encountered in the latter fermenter. 相似文献
45.
46.
Keshavarz Azizi Raftar Shahrbanoo Abdollahiyan Sara Azimirad Masoumeh Yadegar Abbas Vaziri Farzam Moshiri Arfa Siadat Seyed Davar Zali Mohammad Reza 《Probiotics and antimicrobial proteins》2021,13(3):776-787
Probiotics and Antimicrobial Proteins - Hepatic stellate cell (HSC) activation is a key phenomenon in development of liver fibrosis. Recently, Akkermansia muciniphila has been introduced as a... 相似文献
47.
M Selseleh H Keshavarz M Mohebali S Shojaee M Selseleh MR Eshragian F Mansouri MH Modarressi 《The Korean journal of parasitology》2012,50(3):233-238
The precise diagnosis of the acute toxoplasmosis in pregnant women and immunocompromsied patients has critical importance. Most of the commercially available assays use the whole Toxoplasma soluble extract as the antigen. However, the assays currently available for the detection of specific anti-Toxoplasma antibodies may vary in their abilities to detect serum immunoglobulins, due to the lack of a purified standardized antigen. The aim of this study was production and evaluation of the usefulness of the recombinant Toxoplasma gondii GRA7 antigen for the serodiagnosis of Toxoplasma gondii IgM and IgG by ELISA. A total of 70 T. gondii IgM positive sera, 74 T. gondii IgG positive sera, and 60 sera from subjects who were not infected with T. gondii were examined. These sera were shown different absorbance values in ELISA test. To control the specificity of the rGRA7 other parasitic diseases, for example, echinococcosis, malaria, leishmaniasis, fascioliasis, and strongyloidiasis were tested of which none showed positive results. Sensitivity and specificity of the generated recombinant IgG ELISA in comparison with commercial ELISA (com ELISA) were 89% and 90%, and the sensitivity and specificity of the generated recombinant IgM ELISA were 96% and 90%, respectively. The results obtained here show that this antigen is useful for diagnostic purposes. 相似文献
48.
Efficient export of prefolded,disulfide‐bonded recombinant proteins to the periplasm by the Tat pathway in Escherichia coli CyDisCo strains 下载免费PDF全文
Cristina F. R. O. Matos Colin Robinson Heli I. Alanen Piotr Prus Yuko Uchida Lloyd W. Ruddock Robert B. Freedman Eli Keshavarz‐Moore 《Biotechnology progress》2014,30(2):281-290
Numerous high‐value therapeutic proteins are produced in Escherichia coli and exported to the periplasm, as this approach simplifies downstream processing and enables disulfide bond formation. Most recombinant proteins are exported by the Sec pathway, which transports substrates across the plasma membrane in an unfolded state. The Tat system also exports proteins to the periplasm, but transports them in a folded state. This system has attracted interest because of its tendency to transport correctly folded proteins, but this trait renders it unable to export proteins containing disulfide bonds since these are normally acquired only in the periplasm; reduced substrates tend to be recognized as incorrectly folded and rejected. In this study we have used a series of novel strains (termed CyDisCo) which oxidise disulfide bonds in the cytoplasm, and we show that these cells efficiently export a range of disulfide‐containing proteins when a Tat signal peptide is attached. These test proteins include alkaline phosphatase (PhoA), a phytase containing four disulfide bonds (AppA), an antiinterleukin 1β scFv and human growth hormone. No export of PhoA or AppA is observed in wild‐type cells lacking the CyDisCo factors. The PhoA, AppA and scFv proteins were exported in an active form by Tat in the CyDisCo strain, and mass spectrometry showed that the vast majority of the scFv protein was disulfide‐bonded and correctly processed. The evidence indicates that this combination of Tat + CyDisCo offers a novel means of exporting active, correctly folded disulfide bonded proteins to the periplasm. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:281–290, 2014 相似文献
49.
Waqas Hameed Syed Khurram Azmat Moazzam Ali Muhammad Ishaque Sheikh Ghazunfer Abbas Marleen Temmerman Bilal Iqbal Avan 《PloS one》2014,9(8)
Introduction
There is little available evidence of associations between the various dimensions of women''s empowerment and contraceptive use having been examined - and of how these associations are mediated by women''s socio-economic and demographic statuses. We assessed these phenomena in Pakistan using a structured-framework approach.Methods
We analyzed data on 2,133 women who were either using any form of contraceptive or living with unmet need for contraception. The survey was conducted during May - June 2012, with married women of reproductive age (15–49 years) in three districts of Punjab. The dimensions of empowerment were categorized broadly into: economic decision-making, household decision-making, and women''s mobility. Two measures were created for each dimension, and for the overall empowerment: women''s independent decisions, and those taken jointly by couples. Contraceptive use was categorized as either female-only or couple methods on the basis of whether a method requires the awareness of, or some support and cooperation from, the husband. Multinomial regression was used, by means of Odds Ratios (OR), to assess associations between empowerment dimensions and female-only and couple contraceptive methods.Results
Overall, women tend to get higher decision-making power with increased age, higher literacy, a greater number of children, or being in a household that has superior socio-economic status. The measures for couples'' decision-making for overall empowerment and for each dimension of it showed positive associations with couple methods as well as with female-only methods. The only exception was the measure of economic empowerment, which was associated only with the couple method.Conclusion
Couples'' joint decision-making is a stronger determinant of the use of contraceptive methods than women-only decision-making. This is the case over and above the contribution of women''s socio-demographic and economic statuses. Effort needs to be made to educate women and their husbands equally, with particular focus on highly effective contraceptive methods. 相似文献50.
M Selseleh MH Modarressi M Mohebali S Shojaee MR Eshragian M Selseleh E Azizi H Keshavarz 《The Korean journal of parasitology》2012,50(3):199-205
Toxoplasmic encephalitis is caused by reactivation of bradyzoites to rapidly dividing tachyzoites of the apicomplexan parasite Toxoplasma gondii in immunocompromised hosts. Diagnosis of this life-threatening disease is problematic, because it is difficult to discriminate between these 2 stages. Toxoplasma PCR assays using gDNA as a template have been unable to discriminate between an increase or decrease in SAG1 and BAG1 expression between the active tachyzoite stage and the latent bradyzoite stage. In the present study, real-time RT-PCR assay was used to detect the expression of bradyzoite (BAG1)- and tachyzoite-specific genes (SAG1) during bradyzoite/tachyzoite stage conversion in mice infected with T. gondii Tehran strain after dexamethasone sodium phosphate (DXM) administration. The conversion reaction was observed in the lungs and brain tissues of experimental mice, indicated by SAG1 expression at day 6 after DXM administration, and continued until day 14. Bradyzoites were also detected in both organs throughout the study; however, it decreased at day 14 significantly. It is suggested that during the reactivation period, bradyzoites not only escape from the cysts and reinvade neighboring cells as tachyzoites, but also converted to new bradyzoites. In summary, the real-time RT-PCR assay provided a reliable, fast, and quantitative way of detecting T. gondii reactivation in an animal model. Thus, this method may be useful for diagnosing stage conversion in clinical specimens of immunocompromised patients (HIV or transplant patients) for early identification of tachyzoite-bradyzoite stage conversion. 相似文献