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21.
The current experiment was carried out to evaluate the effect of different dietary chromium supplementation sources, chromium oxide (Cr2O3), chromium methionine (Cr‐Met), or chromium yeast (Cr‐yeast), at different levels each (500 or 1,000 ppb) on growth performance, physiological traits, and carcass characteristics of broiler chicks. A total of 490 seven‐day‐old Arbor Acres chicks were randomly distributed into 7 experimental groups each in 10 replicates of 7 birds each. The groups were control, 500 ppb Cr2O3, 1,000 ppb Cr2O3, 500 ppb Cr‐Met, 1,000 ppb Cr‐Met, 500 ppb Cr‐yeast, and 1,000 ppb Cr‐yeast. The results showed significant superiority of the organic chromium sources (Cr‐Met or Cr‐yeast) concerning body weight and weight gain, the group supplemented with 1,000 ppb Cr‐yeast consumed the lowest feed (3,185 g) and had the best feed conversion ratio (1.60) compared to the control (1.73). The chromium treatments recorded significantly better protein and lipid profile, antioxidant status, and immunological parameters than the control group. Similarly, dietary chromium supplementation increased carcass yield and decreased intestinal pathogenic bacteria. In conclusion, supplementing broiler diets with organic chromium sources at 1,000 ppb promotes growth performance, physiological traits, and carcass characteristics; such chromium treatments enhanced the antioxidant status and immunity levels of broilers.  相似文献   
22.
During the period from January 2002 to December 2003, serum samples were collected from 104 small ruminant flocks consisting of 18 sheep flocks, 27 goat flocks, and 59 mixed flocks containing both sheep and goats in northern Jordan. Only female sheep and goats were sampled. At least five females aged over 2 years per flock per species were sampled and examined for Mycoplasma mycoides subspecies capri using the latex agglutination test. To increase the chances of detecting positive flocks, sick or older ewes were sampled. Specific information was obtained using a questionnaire to identify potential risk factors for M. mycoides subsp. capri seropositivity in small ruminants. The true flock-level seroprevalences of M. mycoides subsp. capri were 34%, 32%, and 38% in small ruminants (sheep and goats), sheep, and goats, respectively. Differences between flock-level seroprevalences in sheep and goats were not significant (p = 0.7). Multivariable logistic regression analysis of 21 production and health management practices showed four to be associated with M. mycoides subsp. capri seropositivity including flocks which were grazed and fed concentrate supplement (OR = 4.6), improper cleaning of milking utensils (OR = 4.7), buying new animals to replace culled ones (OR = 0.3), and treating against helminths when clinical signs of helminth infections appear (OR = 0.4).  相似文献   
23.
为实现对大量元素水溶肥种类的快速准确辨识,根据水溶肥的介电特性设计了一个传感器,并在此基础上采用特征频率法,研制了一种大量元素水溶肥快速辨识装置,主要由±5V稳压电路、单片机控制电路、激励信号发生电路、传感器、真有效值转换电路和LCD显示模块组成。以市面上常见的尿素、普钙、硫酸钾、磷酸氢二铵、磷酸二氢钾和硝酸钾6种大量元素水溶肥作为试验对象,在1 kHz~10 MHz激励信号频率范围内研究了其频率响应特性,得出了9个用于辨识6种大量元素水溶肥的激励信号特征频率,即30、40、50、600、700、800 kHz和3、4、5 MHz。根据各种水溶肥分别在9个特征频率处的响应模式,设计了对6种大量元素水溶肥的辨识策略。该装置的辨识性能采用234组不同类型和浓度的待测水溶肥进行验证试验,结果表明:该装置的辨识准确率为98.3%,完成1次辨识的平均时间为14.3s,最长不超过19.5 s,表明该装置具有良好的快速性和准确性,满足实际应用要求。  相似文献   
24.

Background  

Studies have shown that insomnia is a common sleep disorder among patients with end-stage renal disease (ESRD). This study aimed to assess the prevalence of insomnia in Saudi patients with ESRD who are on maintenance dialysis.  相似文献   
25.
Serological detection of Mycoplasma agalactiae was carried out in 104 small ruminants flocks consisting of 18 sheep, 27 goat and 59 flocks containing both sheep and goats in northern Jordan between 2002 and 2003. At least 5 serum samples per flock were tested using an indirect ELISA for antibodies to M. agalactiae. To increase the chances of detecting this mycoplasma, sick or older animals were sampled. A high seropositivity to M. agalactiae was found in small ruminants suggesting a major role for M. agalactiae in contagious agalactia in northern Jordan. There was no significant difference in the seroprevalence of M. agalactiae in sheep and goats at flock level (X(2)=0.14, d.f.=1, p=0.7). A total of 31 variables including production and health management practices were tested as risk factors for seropositive flocks and analyzed using logistic regression analysis. Increasing risk factors for M. agalactiae seropositive flocks were: using outsider rams, improper cleaning of the milking utensils and separating young from dam, with odds ratios of 5, 3, 4.2, respectively; having mastitis problems in the flock was negatively associated (p=0.04) with M. agalactiae seropositivity. Educating small ruminant farmers to avoid the use of outsider rams, ensuring adequate cleaning of milking utensils and separating the young from dams would enhance the health of small ruminants.  相似文献   
26.
Nycodenz density centrifugation (NDC) is an isolation method that allows extraction of both culturable and unculturable bacterial cells from soil, to be used in further downstream analysis; however, to date there has been a lack of information concerning the efficiency of this method. The aim of this study was therefore to investigate the overall efficiency of NDC extractions from soil and to identify sampling bias, if any.Bacterial cells were extracted from three soil plots from the Danish CRUCIAL field trial using an already established NDC protocol. To evaluate all aspects of the NDC procedure, DNA was extracted directly from soil, from NDC-extracted cells, and from the soil pellets left after NDC. Bacterial diversity was assessed by PCR amplification of the V4-V6 regions of the 16S rRNA from the extracted DNA followed by sample-tagged amplicon-pyrosequencing using the 454 Genome Sequencer FLX system. Sequences were processed and analyzed using the Ribosomal Database Project’s (RDP) Pyrosequencing Pipeline tools.In this study, we show that extraction of bacteria from soil using NDC can result in significant biases in the form of either over- or underrepresentation of specific bacterial phyla commonly found in soil. Furthermore, rarefaction analysis, analysis of similarity, multidimensional scaling plots and analysis of variance showed that the diversity in the NDC-extracted sample was reduced significantly compared to both the original soil sample and the remaining NDC-pellet. To further study the soil diversity a mathematical model was employed to estimate how many sequences would be required in order to find 95% of all operational taxonomic units (OTUs) in the soil. The model estimated that the soil contains approximately 29,400 OTUs and that just 351,500 sequences are needed to cover 95% of the bacterial biodiversity, the equivalent of one full standard GS FLX run.  相似文献   
27.
The current study was conducted to diagnose avian leukosis in naturally infected Brahma backyard chickens in southern parts of Iraq, on the basis of clincopathological findings and serological detection by using antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) in suspected tumor cases in field conditions. In this study the avian leukosis was mostly observed in birds from 16 to 22 weeks of age, as well as the infected flocks showed a low mortality rate ranging from 5–6%. Typical variable sized grey to yellow obvious tumor-like nodular lesion was demonstrated on the surface of enlarged visceral organs such as liver, spleen, kidney and duodenum, as in white meat-type chickens. The histopathological features revealed massive infiltration of monomorphic lymphocytes in which the lymphoblasts were predominant in the liver, kidney, spleen and duodenum. In this study, a total of 40 sera were tested for ALV P27 antigen by ELISA technique. Thirty-five out of forty sera (87.5%) obtained from Brahma chickens tested positive to ALV P27 antigen and a higher percentage (88.58%) of the chicken sera were strongly positive and had (EUs > 75%). Based on these findings, avian leukosis was concluded to be associated with this pathological condition in Iraqi backyard flocks. This is the first report of the presence of the avian leukosis in visceral samples of Brahma breed. It seems that commercial poultry population in Iraq is not far from the threat of the avian leukosis, and surveillance for avian leukosis is needed.  相似文献   
28.
The tumor microenvironment is a nutrient-deficient region that alters the cancer cell phenotype to aggravate cancer pathology. The ability of cancer cells to tolerate nutrient starvation is referred to as austerity. Compounds that preferentially target cancer cells growing under nutrient-deficient conditions are being employed in anti-austerity approaches in anticancer drug discovery. Therefore, in this study, we investigated physcion (1) and 2-(2′,3-epoxy-1′,3′,5′-heptatrienyl)-6-hydroxy-5-(3-methyl-2-butenyl) benzaldehyde (2) obtained from a culture extract of the marine-derived fungus Aspergillus species (sp.), which were isolated from an unidentified marine sponge, as anti-austerity agents. The chemical structures of 1 and 2 were determined via spectroscopic analysis and comparison with authentic spectral data. Compounds 1 and 2 exhibited selective cytotoxicity against human pancreatic carcinoma PANC-1 cells cultured under glucose-deficient conditions, with IC50 values of 6.0 and 1.7 µM, respectively. Compound 2 showed higher selective growth-inhibitory activity (505-fold higher) under glucose-deficient conditions than under general culture conditions. Further analysis of the mechanism underlying the anti-austerity activity of compounds 1 and 2 against glucose-starved PANC-1 cells suggested that they inhibited the mitochondrial electron transport chain.  相似文献   
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