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OBJECTIVE: To examine the validity of the presence of mucin, utilizing a semiquantitative, statistical approach, as a criterion for distinguishing low to intermediate grade mucoepidermoid carcinoma (ME) from Warthin's tumor (WT). STUDY DESIGN: We selected histologically established fine needle aspiration (FNA) cases of ME (26) and WT (30) from a six-year period (January 1995-January 2001). Mucicarmine staining was performed on the FNA preparations. The amount of mucin detected was rated on a scale of 1-3, as follows: 1 = no mucin present, 2 = mucin present in the background and < 5% of tumor cells, and 3 = mucin present in the background and > or = 5% tumor cells. The scores for the 30 WTs and 26 MEs were tabulated and analyzed for statistical significance utilizing the Student t test. RESULTS: The mean mucin score for the 26 MEs was 1.81, SD .63. The mean mucin score for the 30 WTs was 1.52, SD .74. There was no statistically significant difference (P = .122) in the amount of mucin present between MEs and WTs in the 56 aspirate specimens examined. CONCLUSION: Based on the results of this study, the presence of extracellular or intracellular mucin in FNA specimens of salivary gland tumors may not be a reliable criterion for distinguishing WT from ME.  相似文献   
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This study aimed to evaluate whether the host genetic background impact the ruminal microbial communities of the progeny of sires from three different breeds under different diets. Eighty five bacterial and twenty eight methanogen phylotypes from 49 individuals of diverging sire breed (Angus, ANG; Charolais, CHA; and Hybrid, HYB), fed high energy density (HE) and low energy density (LE) diets were determined and correlated with breed, rumen fermentation and phenotypic variables, using multivariate statistical approaches. When bacterial phylotypes were compared between diets, ANG offspring showed the lowest number of diet-associated phylotypes, whereas CHA and HYB progenies had seventeen and twenty-three diet-associated phylotypes, respectively. For the methanogen phylotypes, there were no sire breed-associated phylotypes; however, seven phylotypes were significantly different among breeds on either diet (P<0.05). Sire breed did not influence the metabolic variables measured when high energy diet was fed. A correlation matrix of all pairwise comparisons among frequencies of bacterial and methanogen phylotypes uncovered their relationships with sire breed. A cluster containing methanogen phylotypes M16 (Methanobrevibacter gottschalkii) and M20 (Methanobrevibacter smithii), and bacterial phylotype B62 (Robinsoniella sp.) in Angus offspring fed low energy diet reflected the metabolic interactions among microbial consortia. The clustering of the phylotype frequencies from the three breeds indicated that phylotypes detected in CHA and HYB progenies are more similar among them, compared to ANG animals. Our results revealed that the frequency of particular microbial phylotypes in the progeny of cattle may be influenced by the sire breed when different diets are fed and ultimately further impact host metabolic functions, such as feed efficiency.  相似文献   
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The aim of this study was to investigate whether the phases of the menstrual cycle affect lysine requirement in healthy adult females, as determined by the indicator amino acid oxidation (IAAO) method. Five healthy females with regular menstrual cycles were studied at seven graded levels of lysine intake, in random order, with an oral [13C]phenylalanine tracer protocol in both the follicular and luteal phases. A total of 14 studies were conducted for each subject. Breath and plasma samples were collected according to the standard IAAO protocol. Serum 17beta-estradiol and progesterone concentrations were measured on each IAAO study day. The rate of release of 13CO2 from [13C]phenylalanine oxidation (F13CO2) was measured, and a two-phase linear regression crossover model was applied to determine lysine requirement. F13CO2 was higher during the luteal phase (P < 0.001) and was positively associated with serum concentrations of 17beta-estradiol and progesterone. The F13CO2 data were adjusted for subjects and sex hormones and used to define breakpoints for lysine requirements. The lysine requirement of healthy females in the luteal phase was 37.7 mg.kg(-1).day(-1) and higher (P = 0.025) than that of females in the follicular phase (35.0 mg.kg(-1).day(-1)). At all lysine intake levels, plasma amino acids were lower and phenylalanine oxidation was higher in the luteal relative to the follicular phase. Therefore, we reason that the higher lysine requirement observed in the luteal phase is probably due to higher amino acid catabolism.  相似文献   
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Lymphocytes have a finite and predictable proliferative life span in culture similar to that observed in fibroblasts. In general, the senescence of human fibroblasts is inevitable and irreversible, but their proliferative life span can be extended by certain DNA tumor virus oncogenes, such as the large T antigen of the SV40 virus. Here, we show that human T lymphocytes (HTL) can be stably transfected with SV40 large T and that expression of T antigen extended the life span of T cell cultures. PHA-stimulated HTL were transfected with pSV3neo, an expression vector containing the SV40 early region and the neomycin resistance gene. Transfectants were selected for neomycin (G418) resistance. Control HTL, either mock transfected or transfected with pSV2neo (containing the neomycin resistance gene only), ceased proliferation after about 17 population doublings. In contrast, HTL transfected with pSV3neo underwent more than 170 doublings. pSV3neo-transfected cells expressed SV40 large T RNA, detectable by in situ hybridization, and SV40 T antigen, detectable by immunofluorescence. Greater than 95% of the transfected cells were CD4 positive. These results clearly show that SV40 large T enables HTL to escape senescence. Transfection with SV40 large T may be a valuable method for obtaining long term human T cell lines for studies of both aging and immunology.  相似文献   
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The influence of rumen microbial structure and functions on host physiology remains poorly understood. This study aimed to investigate the interaction between the ruminal microflora and the host by correlating bacterial diversity with fermentation measurements and feed efficiency traits, including dry matter intake, feed conversion ratio, average daily gain, and residual feed intake, using culture-independent methods. Universal bacterial partial 16S rRNA gene products were amplified from ruminal fluid collected from 58 steers raised under a low-energy diet and were subjected to PCR-denaturing gradient gel electrophoresis (DGGE) analysis. Multivariate statistical analysis was used to relate specific PCR-DGGE bands to various feed efficiency traits and metabolites. Analysis of volatile fatty acid profiles showed that butyrate was positively correlated with daily dry matter intake (P < 0.05) and tended to have higher concentration in inefficient animals (P = 0.10), while isovalerate was associated with residual feed intake (P < 0.05). Our results suggest that particular bacteria and their metabolism in the rumen may contribute to differences in host feed efficiency under a low-energy diet. This is the first study correlating PCR-DGGE bands representing specific bacteria to metabolites in the bovine rumen and to host feed efficiency traits.A fundamental understanding of microbial ecology and relationships to ruminant physiology is essential for successful manipulation of ruminal microflora and subsequent improvement in animal production since rumen microflora play important roles in the nutrient and energy uptake of the host (25). Hence, principles such as niche occupancy, selective pressure, adaptation, and interactions among populations (42) as well as the kinetics of substrate utilization (18) have to be taken into account when evaluating the ruminal microflora and host interactions. Bacterial density in the rumen is high, with direct counts as high as 10 billion cells per gram of ruminal contents (19, 33). Due to the limited understanding of the complex nature of the microbial component and activities in the rumen, the mechanisms of host-microbe and microbe-microbe interactions and whether such interactions impact host biology have not been well established.Many recent studies have employed molecularly based culture-independent techniques to investigate bacterial profiles (11, 22, 24, 39). PCR-denaturing gradient gel electrophoresis (PCR-DGGE) analysis has been applied to assess ruminal microbial diversity based upon PCR-amplified 16S rRNA fragments to study community interactions (34), monitor populations shifts (23), and screen clone libraries (10). The PCR-DGGE banding patterns are considered to be representative of the dominant bacterial groups (26) and can be applied to screen changes of dominant species in the microflora for large numbers of environmental samples. A new terminology of “microbiome” has been applied to the study of the rumen microbial community, and such studies have further confirmed the complexity of this environment (7). However, many questions remain unanswered. For example, how does the microbiome change in large numbers of animals in response to host, diet, environment, health, and other factors? Which is more important to the host, the whole microbiome or the core microbiome? What is the function of a particular microbiome? Therefore, defining the ruminal microbiome to study its functions and interactions with the host has been an immense challenge. The selection of the rumen microbiome with particular functions after screening by culture-independent methods such as PCR-DGGE, therefore, is essential for high-throughput sequence analysis.Feed efficiency is one of the most critical factors that impact feed utilization by cattle. We hypothesized that particular bacterial populations in the rumen are associated with fermentation metabolites, which can also influence host feed efficiency. A recent study suggested that the bacterial structure may be associated with cattle''s residual feed intake (14); however, the small number of animals used in this study did not provide a direct linkage between a particular microbial population and host feed efficiency traits. The rumen microbial community changes in response to the feeding time (20). Since previous studies have shown that the concentration of volatile fatty acids (VFA) at prefeeding had less variation by diet (31) or by feeding cycles (43) and because of limited access to rumen fluid sampling from the examined commercial population in this study, we centered on the characterization of prefeeding dynamics in the ruminal bacteria and in the fermentation metabolites in 58 steers to test our hypothesis. Therefore, we focused on investigating the associations between rumen bacteria and host feed efficiency traits using PCR-DGGE analysis, aiming to identify the functional rumen microflora. The traits evaluated were daily dry matter intake (DMI), average daily gain (ADG), feed conversion ratio (FCR) (feed/gain), and residual feed intake (RFI) to measure the feed efficiency of cattle (1, 2, 28). Furthermore, we developed a multivariate statistical analysis to correlate bacterial PCR-DGGE profiles with fermentation measurements such as VFA and ammonia-nitrogen (NH3-N) in the rumen and with feed efficiency traits, including, DMI, FCR, ADG, and RFI.  相似文献   
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Limited knowledge of the structure and activities of the ruminal bacterial community prevents the understanding of the effect of population dynamics on functional bacterial groups and on host productivity. This study aimed to identify particular bacteria associated with host feed efficiency in steers with differing diets and residual feed intake (RFI) using culture-independent methods: PCR-denaturing gradient gel electrophoresis (DGGE) and quantitative real-time PCR analysis. PCR-DGGE profiles were generated from the ruminal fluid of 55 steers fed a low-energy-density diet and then switched to a high-energy-density diet. Bacterial profile comparisons by multivariate statistical analysis showed a trend only for RFI-related clusters on the high-energy diet. When steers (n = 19) belonging to the same RFI group under both diets were used to identify specific bacterial phylotypes related to feed efficiency traits, correlations were detected between dry matter intake, average daily gain, and copy numbers of the 16S rRNA gene of Succinivibrio sp. in low-RFI (efficient) steers, whereas correlations between Robinsoniella sp. and RFI (P < 0.05) were observed for high-RFI (inefficient) animals. Eubacterium sp. differed significantly (P < 0.05) between RFI groups that were only on the high-energy diet. Our work provides a comprehensive framework to understand how particular bacterial phylotypes contribute to differences in feed efficiency and ultimately influence host productivity, which may either depend on or be independent from diet factors.  相似文献   
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The objective of this study was to investigate the effect of 2 levels of prebreeding nutrition on reproduction in yearling does artificially inseminated (AI) by the intrauterine laparoscopic method. Forty-two does (Alpine = 22 and Saanen = 20) were randomly penned in groups of 7 and were fed 1 of 2 diets. The diets contained 3.2 Mcal DE/d (MAINT) or 3.5 Meal DE/d (HIGH), which was 10 and 20% higher than the National Research Council recommendations for maintenance requirements. The does were on the 2 feed treatments for 8 wk, after which the MAINT group was switched to the HIGH group diet. A week later, they were fitted with Veramix sponges to synchronize estrus. The sponges were removed from 22, 10 and 10 randomly picked does after 17, 22 and 23 d, respectively. All the does showed estrus within 48 h of removing the sponges. Previously frozen Alpine or Saanen semen (0.5 ml) was deposited into the uterus of does exhibiting standing estrus after anesthetizing them with zylazine and ketamine. Pure breeding was practiced. All the does lost weight prior to breeding. Seventeen does (41%) conceived and kidded by AI while the rest returned to estrus about 23 d later. A significant difference (P < 0.05) in the kidding percentage was observed between the 2 breeds (Alpine = 64% and Saanen = 16%), while the kidding percentage between the 2 diets did not differ (P > 0.05). Of the does that kidded, seven (41%) had singletons, eight (47%) had twins, one had triplets and one had quadruplets. Average litter size (kids/doe kidding) by AI was 1.76. Although the does lost weight prior to breeding, this did not affect their reproduction.  相似文献   
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This study focused on the detection of value-added co-products in dried distiller’s grain plus soluble (DDGS), a possibility that could open new avenues for further processing and marketing of DDGS and improving economic sustainability of ethanol industry. Varieties of triticale, wheat and two benchmarks, CPS wheat and Pioneer Hi-Bred corn, were fermented using two very high gravity (VHG) fermentation approaches: jet-cooking and raw starch processing (STARGEN fermentation). DDGS from STARGEN fermentation could be promising sources of value-added co-products. Pronghorn triticale DDGS (STARGEN fermentation) had the highest concentration of sterols (3.7 mg/g), phenolic compounds (13.61 mg GAE/g), and β-glucan (2.07%). CDC Ptarmigan DDGS (STARGEN fermentation) had the highest concentration of tocopherols and tocotrienols (107.0 μg/g), 1.93% of β-glucan, and 53.0 mg/g of fatty acids. AC Reed DDGS (STARGEN method) showed 1.97% of β-glucan. This study shows that proper choice of fermentation approach and feedstock for ethanol production could improve commercial quality of DDGS.  相似文献   
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