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排序方式: 共有123条查询结果,搜索用时 0 毫秒
1.
A feeding trial was designed to examine the effects of copper sulfate pentahydrate (CuSO(4).5H(2)O) on the fatty acid composition and oxidative stability in muscle and adipose tissues of Boer x Spanish goat kids. Fifteen (n = 5 per treatment) goats were fed 0, 100, or 200 mg of supplemental Cu per day as copper sulfate for 98 d. The animals were slaughtered, and LM, s.c. adipose from the sternal region, and mesenteric adipose tissues were collected. Total lipids were extracted with chloroform:methanol (2:1), methylated and isolated via GLC from all tissues. The subsequent peaks were then positively identified by mass spectrometry. Thiobarbituric acid-reactive substances were measured also. In s.c. adipose, dietary Cu significantly decreased C14:0 (P = 0.03) and C16:0 (P = 0.01). In muscle, C15:0 (P = 0.03) was linearly increased by Cu. Dietary Cu supplementation did not influence oxidative stability in goat muscle or s.c. adipose. Copper supplementation at 200 mg/d resulted in a significant increase in malondialdehyde in mesenteric adipose (P = 0.01) compared with the 0 or 100 mg/d groups. These results indicate that lipid composition may differ from depot to depot and that depending on the depot, dietary Cu seems to elicit a variable response on the fatty acid composition. 相似文献
2.
Two experiments were conducted to examine the consequences of attempting to control dystocia in Hereford heifers by restricting nutrition during late pregnancy. Nutritional level was controlled by varying feedlot rations in experiment 1 and by varying pasture availability in experiment 2. In neither experiment was the incidence of dystocia or stillbirths significantly affected by level of nutrition during late pregnancy. Calf birthweight was reduced and dam pelvic growth was retarded when the feed intake of heifers was restricted prior to calving. Clear evidence of the dangers associated with allowing heifers to lose too much weight in late pregnancy was provided by these experiments. The loss of around 0.5 kg/day during the last trimester of pregnancy was associated with weak labour, increase dystocia rates, increased perinatal mortality, reduced calf growth rate, prolonged post partum anoestrus and a reduced pregnancy rate (not all statistically significant differences). These effects were not evident in heifers which were maintaining or gaining weight at a moderate rate during late pregnancy. On the basis of this work it is suggested that heifers should be fed to allow modest rates of bodyweight gain (0--0.5 kg/day) during late pregnancy. 相似文献
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Margo E Chase-Topping Ian Handel Bartlomiej M Bankowski Nicholas D Juleff Debi Gibson Sarah J Cox Miriam A Windsor Elizabeth Reid Claudia Doel Richard Howey Paul V Barnett Mark EJ Woolhouse Bryan Charleston 《Veterinary research》2013,44(1):46
The control of foot-and-mouth disease virus (FMDV) outbreaks in non-endemic countries relies on the rapid detection and removal of infected animals. In this paper we use the observed relationship between the onset of clinical signs and direct contact transmission of FMDV to identify predictors for the onset of clinical signs and identify possible approaches to preclinical screening in the field. Threshold levels for various virological and immunological variables were determined using Receiver Operating Characteristic (ROC) curve analysis and then tested using generalized linear mixed models to determine their ability to predict the onset of clinical signs. In addition, concordance statistics between qualitative real time PCR test results and virus isolation results were evaluated. For the majority of animals (71%), the onset of clinical signs occurred 3–4 days post infection. The onset of clinical signs was associated with high levels of virus in the blood, oropharyngeal fluid and nasal fluid. Virus is first detectable in the oropharyngeal fluid, but detection of virus in the blood and nasal fluid may also be good candidates for preclinical indicators. Detection of virus in the air was also significantly associated with transmission. This study is the first to identify statistically significant indicators of infectiousness for FMDV at defined time periods during disease progression in a natural host species. Identifying factors associated with infectiousness will advance our understanding of transmission mechanisms and refine intra-herd and inter-herd disease transmission models. 相似文献
5.
A live Pasteurella haemolytica vaccine efficacy trial 总被引:3,自引:0,他引:3
C W Purdy C W Livingston G H Frank J M Cummins N A Cole R W Loan 《Journal of the American Veterinary Medical Association》1986,188(6):589-591
A live Pasteurella haemolytica serotype 1 vaccine was used in an efficacy trial conducted on 100 lightweight feeder calves purchased from a Florida ranch. Forty-one calves were inoculated with the vaccine intradermally in the neck. Fifty-nine calves served as nonvaccinated controls. Fourteen days later, the calves were shipped to an order buyer in eastern Tennessee, where the calves were mixed with 60 local calves in a community sale barn for 72 hours. After 3 additional days, the calves were shipped to a research feedlot in Bushland, Tex. They remained in the feedlot for 56 days, and the test was concluded 76 days after vaccination. The P haemolytica vaccine had no significant effect on performance, morbidity, or mortality. There was no significant difference between the vaccinated and nonvaccinated calves in the number of times Pasteurella was isolated. The calves became seropositive to bovine viral diarrhea virus, respiratory syncytial virus, and infectious bovine rhinotracheitis (IBR) virus during the 76-day experiment. All calves initially were seropositive to parainfluenza-3 virus. A virulent outbreak of IBR occurred 30 days after the calves arrived at the feedlot. Before the onset of IBR, the isolation of P haemolytica serotype 1 from nasal turbinates was rare (2 of 500 nasal swabs). After the IBR outbreak, P haemolytica serotype 1 was isolated from 40 of 92 calves. 相似文献
6.
A 20-year-old gelding presented with a history of acute respiratory distress which began immediately after administration of a mineral oil and water mix, via nasogastric intubation, for treatment of suspected gastrointestinal dysfunction. An initial presumptive diagnosis of acute lipoid pneumonia was made; this was further supported by evidence of arterial hypoxaemia and oxygen desaturation on arterial blood gas analysis, ultrasonographic signs of bilateral ventral lung consolidation and a mixed bronchoalveolar-interstitial lung pattern seen on thoracic radiographs. Despite intensive supportive therapy the horse's condition continued to deteriorate and the decision was made for humane euthanasia. Gross necropsy findings supported the clinical diagnosis of lipoid pneumonia. 相似文献
7.
G Zamaratskaia J Babol A Madej EJ Squires K Lundström 《Reproduction in domestic animals》2004,39(3):168-172
This study describes the age-related variation in boar taint compounds, skatole and androstenone, and testosterone, oestradiol-17 beta (E17 beta), oestrone sulphate (ES), dehydroepiandrosterone sulphate (DHEAS), triiodothyronine (T(3)) and insulin-like growth factor-1 (IGF-1) in six boars. Three pairs of littermates of crossbred entire male pigs (from three Yorkshire x Duroc dams and one Hampshire sire) were included. Blood samples were taken at the age of 9-15 weeks and thereafter at weekly intervals from the age of 20-32 weeks. Plasma concentrations of skatole, androstenone, testosterone, E17 beta, ES, DHEAS, T(3) and IGF-1 were measured. We found that skatole levels in boars increased at the age around puberty after an increase in the levels of testicular steroids. Levels of skatole were not associated with the levels of sex steroids, T(3) and IGF-1. However, the increased level of testicular steroids is probably the underlying factor needed for high skatole levels to occur although the specific mechanism leading to increased skatole levels remains unknown. 相似文献
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9.
Immunohistochemical Expression of Growth Factors in the Follicular Wall of Normal and Cystic Ovaries of Sows 下载免费PDF全文
FJF Sant'Ana JL Reis Junior GR Blume EJ Gimeno F Rey HH Ortega 《Reproduction in domestic animals》2015,50(2):327-332
The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF‐I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF‐I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF‐II was very similar to pattern noted in IGF‐I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF‐II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors. 相似文献
10.
Lopez N Graham DJ McGuire R Alliger GE Shao-Horn Y Cummins CC Nocera DG 《Science (New York, N.Y.)》2012,335(6067):450-453
Generation of soluble sources of peroxide dianion (O(2)(2-)) is a challenge in dioxygen chemistry. The oxidizing nature of this anion renders its stabilization in organic media difficult. This Report describes the chemically reversible reduction of oxygen (O(2)) to cryptand-encapsulated O(2)(2-). The dianion is stabilized by strong hydrogen bonds to N-H groups from the hexacarboxamide cryptand. Analogous stabilization of peroxide by hydrogen bonding has been invoked recently in crystalline saccharide and protein systems. The present peroxide adducts are stable at room temperature in dimethyl sulfoxide (DMSO) and N,N'-dimethylformamide (DMF). These adducts can be obtained in gram quantities from the cryptand-driven disproportionation reaction of potassium superoxide (KO(2)) at room temperature. 相似文献