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411.
The use of Papanicolaou-stained touch preparations of gastric antral biopsies for the identification of Campylobacter pylori was examined using specimens obtained from 63 consecutive patients with endoscopic evidence of antral gastritis, with the results compared to routine histologic examination and Warthin-Starry silver staining. Organisms were readily identifiable in the Papanicolaou-stained imprints of the gastric mucus. The sensitivity in detecting organisms was 92.5% for the Warthin-Starry-stained sections, 71.4% for the Papanicolaou-stained imprints and 100% for both techniques combined. False-negative imprints were attributed to poor smears and/or the submission of duodenal tissue rather than antral biopsies. Properly performed touch preparations stained by the Papanicolaou method are a cost-effective adjunct to Warthin-Starry-stained section for improving the sensitivity of gastric biopsies for the diagnosis of C pylori.  相似文献   
412.
Probiotics and Antimicrobial Proteins - The objective of this work was to explore the effect of two encapsulating polysaccharides (sodium alginate and carrageenan) on the viability of probiotic...  相似文献   
413.
Pakistani camels have been classified socio-geographically into 20 breeds, but they have not yet been subjected to substantial selective pressures and the genetic basis for these breeds is not understood. However, it should be possible to distinguish them by use of molecular data. This study investigated the genetic diversity and population structure within and between two major Pakistani camel breeds, Marecha and Lassi. As no SNP array is currently available, we first identified 63 619 SNPs using a genotyping by sequencing approach. After quality control, a panel of 36 926 SNPs was used in the analysis. Population structure was investigated with a principal coordinate analysis as well as a cluster analysis using NetView , and multilocus heterozygosity analysis to explore between- and within-breed genetic variation. In addition, between-breed variation was explored using the fixation index, FST. We also compared relationship matrices computed using the VanRaden SNP-based method and a method developed specifically for genotyping by sequencing data. Among the two camel breeds, Lassi showed a lower level of genetic diversity whereas Marecha showed a higher level. As a genotyping platform has not yet been developed for the camel, the SNPs discovered in this study will be useful in future genetic studies in camels.  相似文献   
414.
ABSTRACT

This work presents the development and validation of a simple, rapid, and cost-effective spectrophotometric method for quantitative analysis of uric acid in biological samples. The method relies upon uric acid-led reduction of Fe(III) to Fe(II) of sample/standard solutions which stoichiometrically engages ferrozine to form a magenta-colored complex. Different parameters including pH, metal and chelator concentrations, temperature, etc., were optimized for the maximum intensity and stability of the complex. The uric acid concentrations of synthetic/plasma solutions were determined by comparing the color intensity of Fe(ferrozine)3 2+ complex produced by test solution with the standard curve formed by known uric acid concentrations. The method was validated in accordance with ICH guidelines and subjected to human plasma analysis. The results obtained were compared with a reference (enzymatic) method which revealed that there was no significant difference between the two methods at 95% confidence level. The method is highly specific, precise, linear, accurate, and robust.  相似文献   
415.
Ursolic acid (UA) is a ursane-type pentacyclic triterpenoid compound, naturally produced in plants via specialized metabolism and exhibits vast range of remarkable physiological activities and pharmacological manifestations. Owing to significant safety and efficacy in different medical conditions, UA may serve as a backbone to produce its derivatives with novel therapeutic functions. This review aims to provide ideas for exploring more diverse structures to improve UA pharmacological activity and increasing its biological yield to meet the industrial requirements by systematically reviewing the current research progress of UA. We first provides an overview of the pharmacological activities, acquisition methods and structural modifications of UA. Among them, we focused on the synthetic modifications of UA to yield valuable derivatives with enhanced therapeutic potential. Furthermore, harnessing the essential advances for green synthesis of UA and its derivatives by advent of metabolic engineering and synthetic biology are of great concern. In this regard, all pivotal advances for enhancing the production of UA have been discussed. In combination with the advantages of UA biosynthesis and transformation strategy, large-scale microbial production of UA is a promising platform for further exploration.  相似文献   
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417.
In Vitro Cellular & Developmental Biology - Plant - Optimization of in vitro regeneration protocol using multiple input variables is highly significant, and can be achieved by validating the...  相似文献   
418.
Magnetic resonance imaging of total body fat   总被引:7,自引:0,他引:7  
In this study we assessed different magneticresonance imaging (MRI) scanning regimes and examined some of theassumptions commonly made for measuring body fat content by MRI. Wholebody MRI was used to quantify and study different body fat depots in 67 women. The whole body MRI results showed that there was a significant variation in the percentage of total internal, as well as visceral, adipose tissue across a range of adiposity, which could not be predicted from total body fat and/or subcutaneous fat.Furthermore, variation in the amount of total, subcutaneous, andvisceral adipose tissue was not related to standard anthropometricmeasurements such as skinfold measurements, body mass index, andwaist-to-hip ratio. Finally, we show for the first time subjects with apercent body fat close to the theoretical maximum (68%). This studydemonstrates that the large variation in individual internal fatcontent cannot be predicted from either indirect methods or directimaging techniques, such as MRI or computed tomography, on the basis ofa single-slice sampling strategy.

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419.
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