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61.
To obtain a basal concentration of serum Haptoglobin (Hp) in cattle in Taiwan, Hp concentrations were measured from serum samples collected from 10 healthy heifers, every week for one year. The values were also compared with those collected from 15 cows diagnosed with postpartum metritis. The heifers were successfully impregnated by artificial insemination six months after the tests. Hp concentrations were also measured in the serum collected from 11 other cows within 3 weeks after parturition. The Hp assay developed in this study gave a good correlation (r=0.893)with Western blotting. The Hp concentration of 454 serum samples from the 10 heifers had a mean value of 83.6 +/- 34.1 mg/l, and there was no significant difference among individual heifers. The basal value of Hp in heifers was calculated as less than 73.6 mg/l. No significant difference in Hp concentration was observed among the 10 heifers during cold and warm seasons (19.8 +/- 2.2 degrees C vs 27.3 +/- 1.4 degrees C), or before and after pregnancy. The mean serum Hp concentration from cows suffering from postpartum reproductive disorders was 1133.5 +/- 627.1 mg/l, which was significantly greater than the serum of healthy heifers and postpartum cows (104.6 +/- 61.0 mg/l) (P<0.05). These results demonstrate that Hp concentration may be a useful indicator for cows with postpartum reproductive disorders.  相似文献   
62.
Canine mammary tumours (CMTs) are the most prevalent neoplasms in female dogs. Despite the high incidence of such tumours, a lack of easily accessible biomarkers still impedes early diagnosis of malignant CMTs. Herein we identify thymidylate synthetase (TYMS), hyaluronan and proteoglycan link protein 1 (HAPLN1) and insulin‐like growth factor‐binding protein 5 (IGFBP5) as CMT antigens eliciting corresponding autoantibodies in CMT cases. We establish enzyme‐linked immunosorbent assays (ELISAs) to detect autoantibodies to TYMS (TYMS‐AAb), HAPLN1 (HAPLN1‐AAb) and IGFBP5 (IGFBP5‐AAb) in sera from 81 dogs with malignant CMTs (41 in Stage I), 24 with benign CMTs and 35 healthy controls. Levels of all the three autoantibodies are elevated in the malignant group compared with the healthy or the benign group; notably, the elevated autoantibody levels significantly correlate with the stage‐I CMTs. For discriminating malignant CMTs from healthy control, the area under curve (AUC) of TYMS‐AAb is 0.694 with specificity of 82.9% and sensitivity of 50.6%. The AUC of utilising HAPLN1‐AAb for distinguishing the stage‐I CMTs from healthy controls is 0.711 with specificity of 77.1% and sensitivity of 58.5%. In differentiating malignant CMTs from the benign, the AUC of IGFBP5‐AAb reaches 0.696 with specificity of 70.8% and sensitivity of 67.9%, and a combination of IGFBP5‐AAb and TYMS‐AAb increases the AUC to 0.72. Finally, the AUC of combined HAPLN1‐AAb and IGFBP5‐AAb in discriminating the stage‐I CMTs from the benign achieves 0.731. Collectively, this study highlights a significant association of the three serum autoantibodies with early stage malignant CMTs.  相似文献   
63.
Three variations to the structure of the nicotinamide adenine dinucleotide (NAD)-dependent L-lactate dehydrogenase from Bacillus stearothermophilus were made to try to change the substrate specificity from lactate to malate: Asp197----Asn, Thr246----Gly, and Gln102----Arg). Each modification shifts the specificity from lactate to malate, although only the last (Gln102----Arg) provides an effective and highly specific catalyst for the new substrate. This synthetic enzyme has a ratio of catalytic rate (kcat) to Michaelis constant (Km) for oxaloacetate of 4.2 x 10(6)M-1 s-1, equal to that of native lactate dehydrogenase for its natural substrate, pyruvate, and a maximum velocity (250 s-1), which is double that reported for a natural malate dehydrogenase from B. stearothermophilus.  相似文献   
64.
Potassium bromate (KBrO3) is an oxidizing agent used as a food additive which causes kidney damage as a potent nephrotoxic agent, and the mechanism may be explained by the generation of oxygen free radicals. Our experiments showed that single intraperitoneal administration of 200 mg/kg KBrO3 could induce serious kidney damage, with an increase in serum blood urea nitrogen (BUN) and creatinine levels. Five-day oral administration of bilberry ( Vaccinium myrtillus L.) extract at 50, 100, and 200 mg/kg resulted in a reversal in serum BUN and creatinine to normal levels and decreased kidney malondialdehyde (MDA), nitric oxide (NO), and xanthine oxidase (XOD) levels. Also, bilberry extract improved oxygen radical absorbance capacity (ORAC) levels in kidney tissue, which showed that bilberry extract reduced the degree of oxidative stress and kidney damage induced by KBrO3. These findings demonstrate that the protective effect of bilberry extract is attributed to its free radical scavenging activity and lipid peroxidation inhibitory effect.  相似文献   
65.
Our experiments showed that 18 h restraint stress could induce serious liver damage, with an increase in plasma alanine aminotransferase (ALT) level (107.68 +/- 3.19 U/L vs 18.08 +/- 1.46 U/L). Meanwhile, we observed increased malondialdehyde (MDA) levels and lowered oxygen radical absorbance capacity (ORAC) values in plasma and liver of restraint mice compared with starved mice. Bilberry extract (containing 42.04% anthocyanins) was oral administrated to mice at 50, 100, and 200 mg/(kg x day) for five days, which remarkably decreased plasma ALT level to 17.23 +/- 2.49 U/L at the dose of 200 mg/(kg x day) and thus alleviated stress-induced liver damage. In addition, bilberry extracts increased glutathione (GSH) and vitamin C levels and significantly decreased MDA and nitric oxide (NO) levels in the liver tissues. These results suggest that bilberry extract plays an important role in protecting against restraint stress-induced liver damage by both scavenging free radicals activity and lipid peroxidation inhibitory effect. This study showed the beneficial health effects of bilberry extract through its antioxidative action.  相似文献   
66.
This study aimed to develop a synbiotic combination with probiotic, Lactobacillus plantarum 7–40 and one of three prebiotics, fructooligosaccharide (FOS), galactooligosaccharide (GOS) and mannan oligosaccharide (MOS). The best in vitro growth was observed when probiotic was cultured in the medium containing either FOS or GOS as the sole of carbon source. The analysis of enzyme activity revealed that GOS induced the highest activities of protease and β‐galactosidase of probiotic. Based on the findings, probiotic + GOS were selected as synbiotic to evaluate if it could promote the growth of white shrimp, Litopenaeus vannamei. For this, four diets, including a basal diet with no GOS or probiotic (control), 0.4% GOS (PRE), 108 CFU probiotic kg?1 (PRO) and 0.4% GOS in combination with 108 CFU probiotic kg?1 (SYN), were fed to shrimp for 60 days, and then the growth performance, intestinal microbiota (including total Vibrio counts, VBCs; and lactic acid bacteria, LAB) and digestive enzyme (including protease, leu‐aminopeptidase and β‐galactosidase) were evaluated. The weight gain (WG) of shrimp fed the PRO did not significantly differ from those of control (> .05). Shrimp fed the SYN had significantly higher WG compared with the other treatments (< .05). In addition, the SYN‐fed shrimp had significantly higher LAB and protease, leu‐aminopeptidase and β‐galactosidase activity (< .05). The lowest presumptive Vibrio count (VBC) was also observed in intestines of SYN‐fed shrimp. Therefore, we suggested that Lac. plantarum 7–40+ GOS can be used as a synergistic synbiotic for shrimp culture.  相似文献   
67.
The aquaculture of spotted hard clams, Meretrix petechialis, is a well‐developed industry in Taiwan. Spats have been produced for decades through artificial propagation using broodstocks selected from neighbouring culture farms on the basis of size and maturity, and the produced spats are resold to these culture farms. Although mass mortality occurs frequently in this practice, the effect of inbreeding depression has never been evaluated. Therefore, genetic diversity of 173 spotted hard clams from museums, two culture farms and three purchased populations was examined in this study. Phylogenetic analyses, based on either COI or cyt b fragments, indicated a division into lineages A and B among the samples. Cultured clams, except for one clustered with M. lusoria, museum specimens, and purchased samples from Hsinchu were all grouped into lineage A. The remaining two purchased populations were placed in both lineages. Compared with cultured clams from the Chinese coast in a previous study, our results exhibited a much lower haplotype (0.354 vs. 0.900) and nucleotide diversity (0.00113 vs. 0.00543). However, whether the loss of genetic variation is a consequence of inbreeding or the founder effect in the initial small broodstocks is unclear. The introduction of broodstocks from northern Vietnam and southern China may facilitate the management of genetic diversity. Environmental factors that potentially cause mass mortality require further investigation.  相似文献   
68.
Taiwan has prioritized bed and breakfast (B&B) business performance improvement in its tourism policies because B&Bs are a sustainable business model that can boost local economy through rural tourism. In order to identify the factors that can improve business performance, this research uses directional distance function and metafrontier approach to evaluate the technical efficiency of 18 cities and counties with B&Bs in Taiwan from 2011 to 2016. Results are divided into four geographic regions: Northern, Central, Southern, and Eastern Taiwan; technology gap ratios are computed to determine the degree of technical gaps for each region in order to provide information to potential B&B owners when selecting their accommodation location or region, to aid B&B managers in tailoring their business models and marketing strategies to maximize total revenues or minimize inputs, and to facilitate tourism, small businesses, and local economy with the support of the Taiwanese government.  相似文献   
69.
台湾红壤及森林土壤中之氧化铁   总被引:3,自引:0,他引:3       下载免费PDF全文
本文综合汇整近年来在台湾,应用高梯度磁场分离技术,配合一般化学分析,X-射线衍射法,磁测分析,电子显微镜观察与电子衍射鉴定,以及铁-57穆期堡尔谱学分析等方法,研究红壤与森林土壤中,氧化铁的分布及其结构性质之成果回顾;关于氧化铁之分布情形,其研究结果显示:台湾红壤中普遍存在有赤铁矿与针铁矿等氧化铁矿物,而在化育自大屯山更新世纪安山岩母质与澎湖列岛更新世纪玄武岩母质的红壤中,以及兰屿绿岛海边之银白色  相似文献   
70.
Protein digestibility in sorghum (Sorghum bicolor (L.) Moench) lines was determined using two standard procedures (pepsin digestibility and pH‐stat) and compared with a newly developed, rapid electrophoresis‐based screening assay. The new assay was based on the rate of α‐kafirin disappearance after pepsin digestion. α‐Kafirin, the major sorghum storage protein, makes up ≈60–70% of the total protein in the grain. In the new assay, samples were first digested with pepsin for 1 hr, and undigested proteins were then analyzed by SDS‐PAGE. The intensitizes of the undigested α‐kafirin bands were measured. Higher band intensity indicated lower protein digestibility. The new assay was significantly correlated with the standard pepsin digestibility assay (r = −0.96, n = 16) after which it was patterned. The same was true of the pH‐stat procedure (r = −0.85, n = 16). This implies that the new assay is comparable to existing procedures and can be used for screening sorghum lines for protein digestibility. Two groups consisting of high‐protein digestibility and wild‐type sorghum lines were identified when the new assay was tested on 48 sorghum lines derived from crosses of wild‐type and mutant high protein digestibility lines, indicating that the new assay was efficient in differentiating between the two groups. Advantages of the new assay over the standard procedures include considerable reduction in analysis time and sample size required for the analysis. For example, analysis time was reduced by 20% and sample size by 10% when the new assay was used as compared with the pH‐stat procedure. We estimate that ≈60 sorghum lines can be screened in a day by a single operator using the new assay.  相似文献   
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