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91.
To assess the impact of acute caloric shortage on reproduction, rabbit does were either fed ad libitum (control, AL), or fasted for 24 (STF) or 48 h (LTF) before induction of ovulation with GnRH injection. Blood samples were collected during the last 3 h of fasting, and the following 4 h after GnRH injection, when feed was provided again, to measure plasma concentrations of LH, estradiol-17beta, leptin, insulin, T3, corticosterone, glucose, and NEFA. Before re-feeding, plasma leptin, insulin, and T3 concentrations were lower (P < or = 0.01) in both fasted groups than in controls, but then gradually increased following realimentation to match those of controls. During fasting, corticosterone levels were higher (P < or = 0.01) in LTF than in STF and AL does, but decreased to control values soon after realimentation. During fasting, plasma glucose concentrations did not differ among groups, but upon re-feeding they markedly increased (P < or= 0.01) both in STF and LTF does. NEFA levels were also more elevated (P < or = 0.01) in fasted rabbits than in controls, and rapidly decreased (P < or = 0.01) after re-feeding. Following GnRH injection, LH peak was lower (P < or = 0.01) in LTF than in AL and STF does. Estradiol-17beta showed higher pulse frequency and amplitude in AL than in STF and LTF does. Compared to controls, receptivity rate of STF and LTF artificially inseminated does declined respectively by -20.5% (P < or = 0.05) and -22.7%, and fertility rate by -23.9% (P < or = 0.05) and 21.4%, but no difference was found in ovulation rate. In summary, nutritional status of does, as modified by fasting, greatly influenced fertility, metabolic and reproductive hormones.  相似文献   
92.
93.
Reversed phase high performance liquid chromatography (RP-HPLC) on a semimicro separation scale was employed to develop a straightforward method for the simultaneous separation, identification, and quantification of phenolic compounds occurring in whole berries of Vitis vinifera, which comprise phenolic acids, flavonols, catechins, stilbenes, and anthocyanins. A C-18 narrow bore column of 150 x 2.0 mm I.D. and a semimicro photodiode array detector (PDA) cell of 2.5 microL, in conjunction with a mass spectrometry detector equipped with an electrospray ionization source (ESI-MS) to confirm peak identification, were employed. The C-18 narrow bore column was eluted by a multisegment gradient of increasing concentration of acetonitrile in water-formic acid solution that was optimized on the basis of the results of a study carried out to evaluate the influence of mobile phase composition and gradient shape on separation performance and detection sensitivity by ESI-MS. The identification of individual phenolic compounds was performed on the basis of their retention times and both UV-visible and mass spectra, acquired by a mass spectrometer (MS) equipped with an electrospray ionization (ESI) source, employed in conjunction with the PDA detector. Libraries comprising retention times, UV-visible, and mass spectra for major phenolic compounds expected in grape berries were made by subjecting solutions of each phenolic standard to the optimized RP-HPLC method. Quantification of individual compounds was performed by the external standard method using a six point regression graph of the UV-visible absorption data collected at the wavelength of maximum absorbance of each analyte determined by the PDA spectra. The RP-HPLC method was validated in terms of linearity of calibration graphs, limits of detection, limits of quantification, repeatability, and accuracy, which was evaluated by a recovery study. The developed method was successfully applied to identify the phenolic compounds occurring in the whole berries of nine red and one white grape of different varieties of Vitis vinifera, comprising some autochthonous varieties of south Italy such as Aglianico, Malvasia Nera, Uva di Troia, Negroamaro, Primitivo, and Susumaniello. Large differences in the content of phenolic compounds was found in the investigated grape varieties. As expected, only glycosilated flavonols were quantified, and the total amount of these compounds was higher in the whole berries of red grapes than in the white Moscato, where the most abundant phenolic compound was quercetin 3-O-glucoside. In almost all samples, the most and least abundant anthocyanins were malvidin 3-O-glucoside and cyanidin 3-O-glucoside, respectively, with the exception of Uva di Troia where the least abundant anthocyanin was delphinidin 3-O-glucoside.  相似文献   
94.
Gall‐bladder diseases are common in dogs and two‐dimensional ultrasonography is a current standard method for diagnosis and treatment planning. However, findings from this modality can be nonspecific. The aim of this retrospective, case series study was to describe conventional and contrast‐enhanced ultrasound (using SonoVue®) findings in a group of dogs with histologically confirmed gall bladder disease. A total of 65 dogs were included. Branchlike, heterogeneous, and homogeneous contrast enhancement of echogenic intraluminal mass‐forming lesions was a contrast‐enhanced ultrasound characteristic of polypoid lesions due to cystic mucosal hyperplasia of the gallbladder and/or tumor, which had different wash‐in and washout characteristics. In dogs with mobile or immobile biliary sludge or mucocele, the echogenic intraluminal masses remained unenhanced. A double rim mark or enhancement defect in the gallbladder wall was a characteristic of edema or necrosis/rupture of the wall, respectively. Conventional ultrasonography correctly identified biliary sludge or mucocele in 36/37 dogs, cholecystitis/edema in 44/47 dogs, necrosis/rupture in 19/25 dogs, and gallbladder neoplasia in three of three dogs with these pathologies. It falsely identified biliary sludge or mucocele in eight of 28 dogs, cholecystitis/edema in three of 15 dogs, necrosis/rupture in 13/37 dogs, and gall‐bladder neoplasia in 20/59 dogs that did not have these pathologies. Contrast‐enhanced ultrasound correctly identified cholecystitis/edema in 42/47 dogs, but falsely identified cholecystitis/edema in three of 18 dogs. It correctly identified necrosis/rupture, benign polypoid lesions, and gallbladder neoplasia in all dogs with no false‐positive results. Findings supported contrast‐enhanced ultrasound as a complement to conventional ultrasonography for dogs with suspected gallbladder pathologies such as edema, necrosis, and rupture.  相似文献   
95.
The polymerase chain reaction (PCR) was used for the specific detection of Phytophthora nicotianae and P. citrophthora in citrus roots and soils. Primers were based on the nucleotide sequences of the internal transcribed space regions (ITS1 and ITS2) of 16 different species of Phytophthora. Two primer pairs, Pn5B–Pn6 and Pc2B–Pc7, were designed specifically to amplify DNA from P. nicotianae and P. citrophthora, respectively. Another primer pair (Ph2–ITS4) was designed to amplify DNA from many Phytophthora species. All primer pairs were assessed for specificity and absence of cross-reactivity, using DNA from 118 isolates of Phytophthora and 82 of other common soil fungi. In conventional PCR, with a 10-fold dilution series of template DNA, the limit of detection was of 1pgl–1 DNA for all the primer pairs (Ph2–ITS4, Pn5B–Pn6, and Pc2B–Pc7). In nested PCR, with primers Ph2–ITS4 in the first round, the detection limit was of 1fgl–1 for both the primer sets (Pn5B–Pn6 and Pc2B–Pc7). Simple, inexpensive and rapid procedures for direct extraction of DNA from soil and roots were developed. The method yielded DNA of a purity and quality suitable for PCR within 2–3h. DNA extracted from soil and roots was amplified by nested PCR utilizing primers Ph2–ITS4 in the first round. In the second round the primer pairs Pn5B–Pn6 and Pc2B–Pc7 were utilized to detect P. nicotianae and P. citrophthora, respectively. Comparison between the molecular method and pathogen isolation by means of a selective medium did not show any significant differences in sensitivity.  相似文献   
96.
97.
The ratio of oleic to linoleic acids (O/L) and the tocopherol content are important features in determining peanut (Arachis hypogaea) seed shelf life. Soluble carbohydrates are known to be important precursors in roasted peanut flavor. The chemical qualities of Argentine grain are different from those of other countries, but no previous studies that associate grain quality and environmental parameters have been performed. Relationships were determined between O/L, tocopherol and sugar contents, and variations in temperature and rainfall during the grain filling period of Florman INTA peanuts. Dry seed yield was used as another explanatory variable. Multiple regression procedure gave mean temperature (positive coefficient) and total precipitation (negative coefficient) as the explanatory variables for variations in O/L. Total precipitation and dry seed yield (both negative coefficients) were found to be predictor variables for tocopherol and sugar contents. Total precipitation was an explanatory variable included in all of the linear regression models obtained in this study.  相似文献   
98.
Peroxisomal defects in neonatal-onset and X-linked adrenoleukodystrophies   总被引:13,自引:0,他引:13  
Accumulation of very long chain fatty acids in X-linked and neonatal forms of adrenoleukodystrophy (ALD) appears to be a consequence of deficient peroxisomal oxidation of very long chain fatty acids. Peroxisomes were readily identified in liver biopsies taken from a patient having the X-linked disorder. However, in liver biopsies from a patient having neonatal-onset ALD, hepatocellular peroxisomes were greatly reduced in size and number, and sedimentable catalase was markedly diminished. The presence of increased concentrations of serum pipecolic acid and the bile acid intermediate, trihydroxycoprostanic acid, in the neonatal ALD patient are associated with a generalized diminution of peroxisomal activities that was not observed in the patient with X-linked ALD.  相似文献   
99.
Seedlings of Phillyrea latifolia L., a Mediterranean shrub, were exposed for 90 days to 110 nl l(-1) ozone (O(3)). Comparison of the cDNA-amplified fragment length polymorphism (cDNA-AFLP) patterns for treated and control plants allowed the identification and cloning of 88 differential sequences induced by O(3). The differential expression of 67 cloned sequences was further confirmed by RT-PCR. The functions of 36 cloned sequences, corresponding to seven of the twelve gene functional classes of Arabidopsis, were presumed on the basis of their homology with characterized gene sequences. Ozone induction of genes homologous to 24 of the clones has been reported in other plant species, whereas the induction of the 12 remaining sequences has not been observed before. Ozone activation of these newly identified genes could be a result of the chronic exposure to low O(3) concentration, because in most previous studies, acute treatments, involving high O(3) dosages, were applied. Possible roles of the cloned sequences in the response of P. latifolia to O(3) and other causes of oxidative stress are discussed.  相似文献   
100.
BACKGROUND: The effect of storage temperature and time on blood gas and acid-base values has been investigated intensively in cattle and dogs; however, data are lacking in other species. OBJECTIVE: The aim of our study was to evaluate changes in gas composition and acid-base values in venous blood stored at different temperatures and for different times in 4 domestic species in Italy. METHODS: Blood samples from Comisana sheep (n = 10), Maltese goats (n = 10), Ragusana donkeys (n = 10), and Thoroughbred horses (n = 10) were analyzed after storage at 23 degrees C (room temperature) for 15 minutes (group I), 23 degrees C for 1 hour (group II), 37 degrees C for 8 hours (group III), and 4 degrees C for 24 hours (group IV). Results were analyzed using a 1-way repeated measures ANOVA. RESULTS: In all species no statistically significant differences in pH values were present in samples stored at 4 degrees C for 24 hours. This also was true for PCO2 in all species except the horse. Except for HCO3- concentration in the horse, significant changes in PO2, HCO3- concentration, base excess, and the standard bicarbonate concentration were observed for all species in samples stored at 4 degrees C. In samples stored for only 1 hour at room temperature, significant changes in most analytes were detected. CONCLUSIONS: The results of this study underline the need for rapid assessment of acid-base samples, because any delay, even for 1 hour, may affect the results.  相似文献   
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