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271.
Sequencing of the 300 bp region of the mitochondrial cytochrome b gene was done. Genetic analysis was carried out for the first time in three exotic breeds (Giant White, Soviet Chinchilla, and German Angora) of European rabbit (Oryctolagus cuniculus) to determine intra- and interspecific variability and to measure the genetic distance. The frequencies of types of mutations (transition, transversion, deletion, and insertion) were also determined. This study throws light on matrilineage of breeds that arise due to interbreed crosses and the genetic management of a stocked rabbit breeding population. 相似文献
272.
Lance W. Noll Pragathi B. Shridhar Diana M. Dewsbury Xiaorong Shi Natalia Cernicchiaro David G. Renter T. G. Nagaraja 《PloS one》2015,10(8)
Culture-based methods to detect the six major non-O157 (O26, O45, O103, O111, O121 and O145) Shiga toxin-producing E. coli (STEC) are not well established. Our objectives of this study were to develop a culture-based method to detect the six non-O157 serogroups in cattle feces and compare the detection with a PCR method. Fecal samples (n = 576) were collected in a feedlot from 24 pens during a 12-week period and enriched in E. coli broth at 40° C for 6 h. Enriched samples were subjected to immunomagnetic separation, spread-plated onto a selective chromogenic medium, and initially pooled colonies, and subsequently, single colonies were tested by a multiplex PCR targeting six serogroups and four virulence genes, stx1, stx2, eae, and ehxA (culture method). Fecal suspensions, before and after enrichment, were also tested by a multiplex PCR targeting six serogroups and four virulence genes (PCR method). There was no difference in the proportions of fecal samples that tested positive (74.3 vs. 77.4%) for one or more of the six serogroups by either culture or the PCR method. However, each method detected one or more of the six serogroups in samples that were negative by the other method. Both culture method and PCR indicated that O26, O45, and O103 were the dominant serogroups. Higher proportions (P < 0.05) of fecal samples were positive for O26 (44.4 vs. 22.7%) and O121 (22.9 vs. 2.3%) serogroups by PCR than by the culture method. None of the fecal samples contained more than four serogroups. Only a small proportion of the six serogroups (23/640; 3.6%) isolated carried Shiga toxin genes. The culture method and the PCR method detected all six serogroups in samples negative by the other method, highlighting the importance of subjecting fecal samples to both methods for accurate detection of the six non-O157 STEC in cattle feces. 相似文献
273.
We examined pollen of all five species of Olinia, the only genus of Oliniaceae (Myrtales), an endemic African family. Olinia pollen is heteropolar with one pole colpate and the other heterocolpate. Restriction of pseudocolpi to one polar face, hence, half pseudocolpi, the inequality of the two polar faces, and the unequal distribution of the colpus segments across the modal plane, are features that distinguish Olinia from all other Myrtales. 相似文献
274.
Edward L. Vezey Varsha P. Shah John J. Skvarla 《Plant Systematics and Evolution》1992,181(3-4):245-254
We present a key synthesizing pollen-sculpture terminology for grains having perforations or lumina of any size and spatial distribution. The key uses quantitative criteria to distinguish five non-overlapping qualitative terms (reticulate, microreticulate, foveolate, scrobiculate, and punctate). In addition, the range of quantitative variation encompassed by these qualitative terms is highlighted, including ways to express and compare that variation using computerized image analysis of SEM micrographs. Finally, a mathematical analysis combined with image-analysis measurements is used to explore the relationships between the terms outlined above and two closely related terms, tectate and semitectate. 相似文献
275.
276.
Hexammine ruthenium(III) chloride, (Ru[NH3]6)Cl3, a potent novel compound, eliminated 100% of pBR322 and pBR329 plasmids fromEscherichia coli, rendering the bacteria vulnerable to the antibiotic-resistance markers carried on these plasmids. However, the curing activity of hexammine ruthenium(III) chloride was pH dependent. 相似文献
277.
William P Sheffield Louise J Eltringham-Smith Sharon Gataiance Varsha Bhakta 《BMC biotechnology》2009,9(1):15-11
Background
The plasma protein α2-antiplasmin (α2AP) is cross-linked to fibrin in blood clots by the transglutaminase factor XIIIa, and in that location retards clot lysis. Competition for this effect could be clinically useful in patients with thrombosis. We hypothesized that fusion of N-terminal portions of α2-antiplasmin to human serum albumin (HSA) and production of the chimeric proteins in Pichia pastoris yeast would produce a stable and effective competitor protein. 相似文献278.
Mangesh R. Bhalekar Varsha Pokharkar Ashwini Madgulkar Nilam Patil Nilkanth Patil 《AAPS PharmSciTech》2009,10(1):289-296
The purpose of this study was to prepare miconazole nitrate (MN) loaded solid lipid nanoparticles (MN-SLN) effective for topical
delivery of miconazole nitrate. Compritol 888 ATO as lipid, propylene glycol (PG) to increase drug solubility in lipid, tween
80, and glyceryl monostearate were used as the surfactants to stabilize SLN dispersion in the SLN preparation using hot homogenization
method. SLN dispersions exhibited average size between 244 and 766 nm. All the dispersions had high entrapment efficiency
ranging from 80% to 100%. The MN-SLN dispersion which showed good stability for a period of 1 month was selected. This MN-SLN
was characterized for particle size, entrapment efficiency, and X-ray diffraction. The penetration of miconazole nitrate from
the gel formulated using selected MN-SLN dispersion as into cadaver skins was evaluated ex-vivo using franz diffusion cell. The results of differential scanning calorimetry (DSC) showed that MN was dispersed in SLN in
an amorphous state. The MN-SLN formulations could significantly increase the accumulative uptake of MN in skin over the marketed
gel and showed a significantly enhanced skin targeting effect. These results indicate that the studied MN-SLN formulation
with skin targeting may be a promising carrier for topical delivery of miconazole nitrate. 相似文献
279.
Ajay Joseph Taewon Lee Carrie L. Moland William S. Branham James C. Fuscoe Julian E.A. Leakey William T. Allaben Sherry M. Lewis Akhtar A. Ali Varsha G. Desai 《Mitochondrion》2009,9(2):149-158
Usnic acid is a lichen metabolite used as a weight-loss dietary supplement due to its uncoupling action on mitochondria. However, its use has been associated with severe liver disorders in some individuals. Animal studies conducted thus far evaluated the effects of usnic acid on mitochondria primarily by measuring the rate of oxygen consumption and/or ATP generation. To obtain further insight into usnic acid-mediated effects on mitochondria, we examined the expression levels of 542 genes associated with mitochondrial structure and functions in liver of B6C3F1 female mice using a mitochondria-specific microarray. Beginning at 8 weeks of age, mice received usnic acid at 0, 60, 180, and 600 ppm in ground, irradiated 5LG6 diet for 14 days. Microarray analysis showed a significant effect of usnic acid on the expression of several genes only at the highest dose of 600 ppm. A prominent finding of the study was a significant induction of genes associated with complexes I through IV of the electron transport chain. Moreover, several genes involved in fatty acid oxidation, the Krebs cycle, apoptosis, and membrane transporters were over-expressed. Usnic acid is a lipophilic weak acid that can diffuse through mitochondrial membranes and cause a proton leak (uncoupling). The up-regulation of complexes I–IV may be a compensatory mechanism to maintain the proton gradient across the mitochondrial inner membrane. In addition, induction of fatty acid oxidation and the Krebs cycle may be an adaptive response to uncoupling of mitochondria. 相似文献
280.