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Summary Comparative studies of lipid composition were made on prolamellar bodies, envelopes and other plastid membranes separately extracted from etiolated, green or greening (intermittent or continuous light) wheat (Triticum sativum L.) leaves. The different membrane fractions were examined by electron microscopy.The major lipid was digalactosyldiglyceride in the envelopes and prolamellar bodies and monogalactosyldiglyceride in stroma lamellae and grana. Phosphatidylcholine represented 60% of total phospholipids in the envelopes, 30% in prolamellar bodies and 14% in grana. All types of envelopes had the same lipid proportions.For all lipids the lowest fatty acid unsaturation was always found in the envelope membranes. The relative amount of {ie193-1} acid in the phosphatidylglycerol of envelopes increased from 4% (etioplasts) to an average of 15% (etiochloroplasts and chloroplasts).Abbreviations DGDG digalactosyldiglyceride - MGDG monogalactosyldiglyceride - PC phosphatidylcholine - PE phosphatidylethanolamine - PG phosphatidylglycerol - PI phosphatidylinositol - PS phosphatidylserine - SL sulfolipid  相似文献   
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As a therapeutic treatment, recombinant human basic fibroblast growth factor (rhbFGF) is usually employed in tissue regeneration, and as an essential component in culture medium for maintaining the induced pluripotent stem (iPS) cell and embryonic stem (ES) cell in an undifferentiated state. Therefore, a large amount of biologically active rhbFGF is required. In this study, silkworm-baculovirus expression vector system (silkworm-BEVS) is employed to achieve a high productivity of recombinant rhbFGF with two small affinity tags (His-tag and STREP-tag) at the N or C-terminus. It is observed that rhbFGF with 30?K signal peptide of silkworm were successfully expressed but are not sufficiently secreted into the culture medium of cultured insect cells. Then we purified the N- or C-tagged intracellular rhbFGF protein and obtained a yield of about 0.7?mg/larva and 1.2?mg/larva, respectively. Although the final yield of the C-tagged rhbFGF is higher than that of the N-tagged, rhbFGF with N-tag demonstrated promising and comparable biological activity, which is evaluated through a mammalian cell proliferation assay. Taken together, these results indicate that silkworm-BEVS could contribute to the mass-production of the biologically active rhbFGF for medical uses.  相似文献   
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Applied Microbiology and Biotechnology - Mucin-type O-glycosylation is initiated by UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (ppGalNAc-Ts or PGANTs), attaching GalNAc to serine or...  相似文献   
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Microsporidia are a large group of obligate intracellular eukaryotic parasites related to Fungi. Recent studies suggest that their diversity has been greatly underestimated and little is known about their hosts other than metazoans, and thus about their impact on the communities at the base of the food web. In this work, we therefore studied the diversity of Microsporidia over one year and identified potential new hosts in small-sized fractions (<150 μm) in a lake ecosystem using a metabarcoding approach coupled with co-occurrence networks and tyramide signal amplification-fluorescent in situ hybridization. Our analysis shows a great Microsporidia diversity (1 472 OTUs), with an important part of this diversity being unknown. Temporal variations of this diversity have been observed, which might follow temporal variations of their potential hosts such as protists and microzooplankton. New hosts among them were identified as well as associations with phytoplankton. Indeed, repeated infections were observed in Kellicottia (rotifers) with a prevalence of 38% (infected individuals). Microsporidia inside a Stentor (ciliate) were also observed. Finally, potential infections of the diatom Asterionella were identified (prevalence <0.1%). The microsporidian host spectrum could be therefore even more important than previously described, and their role in the functioning of lake ecosystems is undoubtedly largely unknown.  相似文献   
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Severe injuries to the extremities often result in muscle trauma and, in some cases, significant volumetric muscle loss (VML). These injuries continue to be challenging to treat, with few available clinical options, a high rate of complications, and often persistent loss of limb function. To facilitate the testing of regenerative strategies for skeletal muscle, we developed a novel quadriceps VML model in the rat, specifically addressing functional recovery of the limb. Our outcome measures included muscle contractility measurements to assess muscle function and gait analysis for evaluation of overall limb function. We also investigated treatment with muscle autografts, whole or minced, to promote regeneration of the defect area. Our defect model resulted in a loss of muscle function, with injured legs generating less than 55% of muscle strength from the contralateral uninjured control legs, even at 4 weeks post-injury. The autograft treatments did not result in significant recovery of muscle function. Measures of static and dynamic gait were significantly decreased in the untreated, empty defect group, indicating a decrease in limb function. Histological sections of the affected muscles showed extensive fibrosis, suggesting that this scarring of the muscle may be in part the cause of the loss of muscle function in this VML model. Taken together, these data are consistent with clinical findings of reduced muscle function in large VML injuries. This new model with quantitative functional outcome measures offers a platform on which to evaluate treatment strategies designed to regenerate muscle tissue volume and restore limb function.  相似文献   
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We wished to assess the clinical safety and pharmacokinetics of ascending doses of a synthetic oligodeoxynucleotide (LR-3280) administered after coronary angioplasty. Antisense oligodeoxynucleotides designed to hybridize with target messenger ribonucleic acid (mRNA) in a complementary fashion to inhibit the expression of corresponding protein also have the ability to bind to extracellular growth factors. LR-3280 has been shown to reduce c-myc expression, inhibit growth and collagen biosynthesis in human vascular cells, and reduce neointimal formation in animal models of vascular injury. After successful percutaneous transluminal coronary angioplasty (PTCA), 78 patients were randomized to receive either standard care (n = 26) or standard care and escalating doses of LR-3280 (n = 52) (doses from 1 to 24 mg), administered into target vessel through a guiding catheter. Overall safety was evaluated by clinical adverse events, laboratory tests, and electrocardiograms. Patency was evaluated by quantitative coronary angiography. There were no clinically significant differences between treated and control patients. No adverse effects of LR-3280 on the patency of dilated coronary arteries were observed. Pharmacokinetic data revealed that peak plasma concentrations of LR-3280 occurred at 1 minute over the studied dose range and rapidly decreased after approximately1 hour, with little LR-3280 detected in the urine between 0-6 hours and 12-24 hours. The intracoronary administration of LR-3280 is well tolerated at doses up to 24 mg and produces no adverse effects in dilated coronary arteries. These results provide the basis for the evaluation of local delivery of this phosphorothioate oligodeoxynucleotide for the prevention of human vasculoproliferative disease.  相似文献   
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