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61.
62.
In skeletal muscle of adults, sepsis reduces protein synthesis by depressing translation initiation and induces resistance to branched-chain amino acid stimulation. Normal neonates maintain a high basal muscle protein synthesis rate that is sensitive to amino acid stimulation. In the present study, we determined the effect of amino acids on protein synthesis in skeletal muscle and other tissues in septic neonates. Overnight-fasted neonatal pigs were infused with endotoxin (LPS, 0 and 10 microg.kg(-1).h(-1)), whereas glucose and insulin were maintained at fasting levels; amino acids were clamped at fasting or fed levels. In the presence of fasting insulin and amino acids, LPS reduced protein synthesis in longissimus dorsi (LD) and gastrocnemius muscles and increased protein synthesis in the diaphragm, but had no effect in masseter and heart muscles. Increasing amino acids to fed levels accelerated muscle protein synthesis in LD, gastrocnemius, masseter, and diaphragm. LPS stimulated protein synthesis in liver, lung, spleen, pancreas, and kidney in fasted animals. Raising amino acids to fed levels increased protein synthesis in liver of controls, but not LPS-treated animals. The increase in muscle protein synthesis in response to amino acids was associated with increased mTOR, 4E-BP1, and S6K1 phosphorylation and eIF4G-eIF4E association in control and LPS-infused animals. These findings suggest that amino acids stimulate skeletal muscle protein synthesis during acute endotoxemia via mTOR-dependent ribosomal assembly despite reduced basal protein synthesis rates in neonatal pigs. However, provision of amino acids does not further enhance the LPS-induced increase in liver protein synthesis.  相似文献   
63.
The high efficiency of protein deposition during the neonatal period is driven by high rates of protein synthesis, which are maximally stimulated after feeding. Infusion of amino acids, but not insulin, reproduces the feeding-induced stimulation of liver protein synthesis. To determine whether amino acid-stimulated liver protein synthesis is independent of insulin in neonates, and to examine the role of amino acids and insulin in the regulation of translation initiation in neonatal liver, we performed pancreatic glucose-amino acid clamps in overnight-fasted 7-day-old pigs. Pigs (n = 9-12/group) were infused with insulin at 0, 10, 22, and 110 ng.kg(-0.66).min(-1) to achieve 0, 2, 6, and 30 microU/ml insulin, respectively. At each insulin dose, amino acids were maintained at fasting or fed levels or, in conjunction with the highest insulin dose, allowed to fall to below fasting levels. Insulin had no effect on the fractional rate of protein synthesis in liver. Amino acids increased fractional protein synthesis rates in liver at each dose of insulin, including the 0 microU/ml dose. There was a dose-response effect of amino acids on liver protein synthesis. Amino acids and insulin increased protein S6 kinase and 4E-binding protein 1 (4E-BP1) phosphorylation; however, only amino acids decreased formation of the inactive 4E-BPI.eukaryotic initiation factor-4E (eIF4E) complex. The results suggest that amino acids regulate liver protein synthesis in the neonate by modulating the availability of eIF4E for 48S ribosomal complex formation and that this response does not require insulin.  相似文献   
64.
Infusion of physiological levels of insulin and/or amino acids reproduces the feeding-induced stimulation of muscle protein synthesis in neonates. To determine whether insulin and amino acids independently stimulate skeletal muscle protein synthesis in neonates, insulin secretion was blocked with somatostatin in fasted 7-day-old pigs (n = 8-12/group) while glucose and glucagon were maintained at fasting levels and insulin was infused to simulate either less than fasting, fasting, intermediate, or fed insulin levels. At each dose of insulin, amino acids were clamped at either the fasting or fed level; at the highest insulin dose, amino acids were also reduced to less than fasting levels. Skeletal muscle protein synthesis was measured using a flooding dose of l-[4-(3)H]phenylalanine. Hyperinsulinemia increased protein synthesis in skeletal muscle during hypoaminoacidemia and euaminoacidemia. Hyperaminoacidemia increased muscle protein synthesis during hypoinsulinemia and euinsulinemia. There was a dose-response effect of both insulin and amino acids on muscle protein synthesis. At each insulin dose, hyperaminoacidemia increased muscle protein synthesis. The effects of insulin and amino acids on muscle protein synthesis were largely additive until maximal rates of protein synthesis were achieved. Amino acids enhanced basal protein synthesis rates but did not enhance the sensitivity or responsiveness of muscle protein synthesis to insulin. The results suggest that insulin and amino acids independently stimulate protein synthesis in skeletal muscle of the neonate.  相似文献   
65.
Summary Measurement of intracellular calcium activity (a Ca c ) by ion-selective microelectrodes has previously been technically limited to relatively large cells (20 m). We now report results obtained with this technique in the small epithelial cells (10 m) of split frog skin using microelectrodes having an outer tip diameter of <0.2 m. The basolateral membrane potential was measured with Ca2+-selective microelectrodes (E Ca sc ) and with reference micropipettes ( sc ) either sequentially or simultaneously in 15 successful experiments. Under baseline conditions,a Ca c was measured to be 215±39nm (mean±se), in close agreement with the mean values estimated from published data obtained withNecturus proximal tubule. Stimulation of Na+ transport across six skins with 1mm serosal 8p-chlorophenylthio-3,5 cyclic AMP (CPTcAMP) increaseda Ca c by a factor of 2.6±0.6. The increase ina Ca c preceded the CPTcAMP-induced increase inI sc. The results of the present study indicate that electrometric determination of intracellular calcium activity is now feasible in a much wider range of cell systems than heretofore possible. CPT cAMP elevates intracellular Ca2+ activity; this phenomenon is an early event, preceding the natriferic effect of CPTcAMP.  相似文献   
66.
Hystrix javanica is endemic species in Indonesia. Study about fetal development of Hystrix javanica are very rare because of sample limitation. This study was carried out to describe the morphometrics and x-ray analysis of three fetuses in different stage to give basic information about fetal development of Hystrix javanica. Three fetus samples fixed in Bouin’s solution was used in this study. Observation was carried out to identify the characteristic of three fetus samples. This included the pattern of hair, body measurements, body volume, and body weight. X-ray analysis was carried out to know the ossification process in the fetal development. Statistical analysis was carried out using Microsoft 365® Excel program software. Three fetus samples had different specific hair pattern, that was hairless, smooth hairs, and smooth hairs with dense-non dense pattern. Body volume of 1st, 2nd, and 3rd fetus were 23mL, 90mL, and 170mL, respectively. Body weight of 1st, 2nd, and 3rd fetus were 19.5g, 79.22g, and 153.18g, respectively. Pearson’s correlation analysis shown strong relationship between total body length, front body length, back body length, horizontal body diameter, vertical body diameter, head length, and head diameter against body volume and body weight of three fetuses. Significant positive correlation was shown between horizontal body diameter, vertical body diameter, and head diameter against body volume and body length with P value < 0.05. Faint radiopaque images showed in the 2nd fetus sample and strong radiopaque images showed in the 3rd fetus sample. Radiopaque images were identified in the teeth, cranium, vertebrae, and extremities bones. In this study we concluded that there was a specific hair pattern in different fetal stage. All body measurements have positive correlation with body volume and body weight and x-ray analysis shown that the ossification of the bone was started to happen while the smooth hair was growth.  相似文献   
67.
Lactobacillus plantarum CNRZ 1228 exhibited heme-dependent catalase activity under environmental conditions similar to those encountered during sausage fermentation. The 1,455-bp catalase gene (katL) was cloned and encoded a protein of 484 amino acids. Expression of katL in a heterologous host showed that katL encodes a functional catalase. PCR screening of selected strains of lactic acid bacteria for katL indicated the presence of similar genes in other strains of lactobacilli.  相似文献   
68.
Invasive species can be detrimental to a nation's ecology, economy and human health. Rapid and accurate diagnostics are critical to limit the establishment and spread of exotic organisms. The increasing rate of biological invasions relative to the taxonomic expertise available generates a demand for high‐throughput, DNA‐based diagnostics methods for identification. We designed species‐specific qPCR primer and probe combinations for 27 economically important tephritidae species in six genera (Anastrepha, Bactrocera, Carpomya, Ceratitis, Dacus and Rhagoletis) based on 935 COI DNA barcode haplotypes from 181 fruit fly species publically available in BOLD, and then tested the specificity for each primer pair and probe through qPCR of 35 of those species. We then developed a standardization reaction system for detecting the 27 target species based on a microfluidic dynamic array and also applied the method to identify unknown immature samples from port interceptions and field monitoring. This method led to a specific and simultaneous detection for all 27 species in 7.5 h, using only 0.2 μL of reaction system in each reaction chamber. The approach successfully discriminated among species within complexes that had genetic similarities of up to 98.48%, while it also identified all immature samples consistent with the subsequent results of morphological examination of adults which were reared from larvae of cohorts from the same samples. We present an accurate, rapid and high‐throughput innovative approach for detecting fruit flies of quarantine concern. This is a new method which has broad potential to be one of international standards for plant quarantine and invasive species detection.  相似文献   
69.
Normalization of single cell RNA-seq data remains a challenging task. The performance of different methods can vary greatly between datasets when unwanted factors and biology are associated. Most normalization methods also only remove the effects of unwanted variation for the cell embedding but not from gene-level data typically used for differential expression (DE) analysis to identify marker genes. We propose RUV-III-NB, a method that can be used to remove unwanted variation from both the cell embedding and gene-level counts. Using pseudo-replicates, RUV-III-NB explicitly takes into account potential association with biology when removing unwanted variation. The method can be used for both UMI or read counts and returns adjusted counts that can be used for downstream analyses such as clustering, DE and pseudotime analyses. Using published datasets with different technological platforms, kinds of biology and levels of association between biology and unwanted variation, we show that RUV-III-NB manages to remove library size and batch effects, strengthen biological signals, improve DE analyses, and lead to results exhibiting greater concordance with independent datasets of the same kind. The performance of RUV-III-NB is consistent and is not sensitive to the number of factors assumed to contribute to the unwanted variation.  相似文献   
70.
A detailed account of the second coelacanth specimen known to have been captured in Indonesian waters is provided. The account is written in the official format of the Coelacanth Conservation Council's (CCC) inventory of known specimens of the living coelacanth Latimeria chalumnae, and the specimen is herein numbered CCC no. 175. Morphological measurements and fin ray counts are recorded. A comparison of these measurements and meristic data with those recorded for Comoran specimens of Latimeria chalumnae shows that the present specimen has a similar allometry to L. chalumnae. Ongoing genetic analyses should reveal the depth of divergence between the two known populations of living coelacanths and help determine if this specimen is conspecific with its Comoran counterparts.  相似文献   
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