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71.
A flow cytometric method has been developed for rapid determination of sperm concentration in semen from various mammalian species. * * Patent Pending, Int. Publication Number WO/00/54026.
All cells containing DNA are stained with SYBR‐14 or propidium iodide (PI) and sperm concentration is determined in relation to an internal standard of fluorescent microspheres (beads). Satisfactory staining can be achieved within 2–3 min and the following flow cytometric analysis on the FACSCount AF System rapidly provides the user with a precise and accurate assessment of the sperm concentration. In this study, the FACSCount AF System and Sperm Counting Reagent (BD Biosciences) was compared with microscopic counting using a Bürker–Türk haemocytometer. In addition, sperm concentration was determined using the Corning 254 spectrophotometer which is used routinely by Danish artificial insemination stations for boars. The results show that the agreement between flow cytometry and microscopic counting is very high. The slope for the regression line was 1.12 (SE = 0.03) with an estimated intercept with the Y‐axis of 22 × 106sperm/ml (SE = 10 × 106 sperm/ml) and an estimated error of the model of 10 × 106 sperm/ml. For the spectrophotometer, the slope of the regression line was 1.09 (SE = 0.07) with an estimated intercept of 137 × 106 sperm/ml (SE = 25 × 106 sperm/ml). The average error made by the spectrophotometer was 55 × 106 sperm/ml. In addition, the results obtained using flow cytometry was highly repeatable (CV = 2.7%) in comparison with the spectrophotometric method (CV = 6.3%). These results indicate that the FACSCount AF System is a valuable tool for precise and accurate assessment of sperm concentration in boar semen and that use of this system may lead to production of more uniform insemination doses containing a specific number of sperm per dose.  相似文献   
72.
Beat‐to‐beat variation of heart rate is reflective of autonomic balance and has been used to assess pain and stress in human beings. The purpose of this investigation was to pharmacologically manipulate the autonomic nervous system and to determine the effect of these manipulations on heart rate variability (HRV) in dogs. Four adult male hound dogs (27 ± 1 kg) were used in the investigation. Each dog was given five treatments: Parasympathetic blockade (glycopyrrolate; 0.01 mg kg–1 IV and 0.01 mg kg–1 IM), parasympathetic stimulation (phenylephrine; 0.005 mg kg–1 IV + 0.05 mg kg–1hour–1), sympathetic blockade (propranolol; 0.11 mg kg–1 IV), sympathetic stimulation propranolol; 0.01 μg kg–1 minute–1), and saline control. At least 48 hours were allowed between treatments. ECG recordings were obtained using an ambulatory ECG monitor. A 5‐minutes period of continuous recording obtained ~30 minutes after initiation of drug administration was used for data analysis. Changes in HRV were evaluated by time and frequency‐domain analysis. The standard deviation of normal R‐R intervals (SDNN), as well as the standard deviation of successive differences in RR intervals (SDSD) were assessed for each treatment. Low frequency (LFP; 0.05–0.15 Hz), high frequency (HFP; 0.15–0.35 Hz), and total (TP; 0.017–0.5 Hz) spectral power were also determined. The LFP:HFP ratio was also evaluated. A two‐way anova with a Tukey's test was used to detect differences (p < 0.05). Administration of glycopyrrolate or isoproterenol increased HR and decreased SDNN and SDSD below control levels. Phenylephrine or propranolol administration were without effect. LFP was diminished by glycopyrrolate and isoproterenol, but was unaffected by phenylephrine and propranolol. HFP, TP, and LFP:HFP were unaffected by treatment. Both branches of the autonomic nervous system influence SDNN and LFP. SDSD, in contrast, is altered primarily by parasympathetic activity. Thus, it appears that parasympathetic activity modulates HRV in the resting dog, as either withdrawal of parasympathetic influence or accentuated sympathetic activity led to significant changes in these measures of HRV. Conversely, augmentation of parasympathetic activity or withdrawal of sympathetic tone minimally affected HRV.  相似文献   
73.
Brucella suis is an emerging, zoonotic disease predominantly affecting dogs and humans that engage in feral pig hunting in Australia and other countries. Although B. suis infection in dogs shares some clinical similarities to the host-adapted species (B. canis), B. suis remains an incompletely understood pathogen in dogs with limited published data on its pathogenesis and clinical features. This case series describes the presentations, diagnosis, and clinical management of B. suis infection in three dogs: (1) a bitch with dystocia, abortion and mastitis; (2) an entire male dog with septic arthritis and presumptive osteomyelitis; and (3) a castrated male dog with lymphadenitis. Unique features of these cases are reported including the first documented detection of B. suis from milk and isolation from lymph nodes of canine patients, as well as the follow-up of pups born to a B. suis-infected bitch. Consistent with previous reports, all three dogs showed a favourable clinical response to combination antibiotic therapy with rifampicin and doxycycline. Individually tailored drug regimens were required based on the clinical presentation and other factors, including owner expectations and compliance with therapy as well as a zoonotic risk assessment (generally considered low, except around time of whelping). The authors include their recommendations for the clinical management of dogs that are at-risk or seropositive for B. suis with or without clinical signs or laboratory-confirmed infection.  相似文献   
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The objective of this retrospective study was to evaluate the effect of management strategies aiming to improve animal well‐being on pregnancy and embryonic death (ED) rates. Breeding records of a cohort of 1206 Thoroughbred mares brought to a stallion station facility, to be bred with the stallions housed there, were evaluated during ten breeding seasons. Mares were blocked according to management strategies in two groups: Stress and Relax. Strategies used to improve animal well‐being (Relax group) were as follows: stopping the teasing routine, reducing or eliminating stall confinement, reducing the number of mares per group and maintaining herd stability during the breeding season. In barren mares, the pregnancy rate was higher in the Relax group (91.8%) when compared to the observed in Stress group (84.7%). However, no difference in pregnancy rates were observed (Stress = 85.2% vs. Relax = 86.2) in foaling mares. ED rate was higher in barren and foaling mares of the Stress group mares (25.5% and 26.8%, respectively) compared with the Relax group (16.1% and 14.7%, respectively). No significant differences were observed on foal heat pregnancy rate between groups; yet, the embryo loss on foal heat was significant reduced in Relax mares (Relax = 8.7% vs Stress = 24.5%). In conclusion, management strategies aimed to reduce social stress can reduce early pregnancy losses and the average cycles per pregnancy, improving reproductive performance in mares.  相似文献   
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Heat shock proteins (HSPs) act as molecular chaperones with important regulatory functions. HSPs are considered to be essential factors in animal reproduction. In view of seasonal variations in the secretory activity of the reproductive tract of mature roe deer (Capreolus capreolus), the aims of this study were to identify HSPs in the epididymides and compare the expression of the identified proteins in three periods of the reproductive season. Two‐dimensional polyacrylamide gel electrophoresis revealed the highest number of polypeptides in homogenates of epididymal tissues and in caput, corpus and cauda epididymal fluids throughout the reproductive season. Epididymal tissue homogenates and epididymal fluids were analysed by tandem mass spectrometry (MS/MS) to reveal 31 polypeptides with enzymatic activity, including polypeptides with antioxidant properties, structural and cell signalling functions. Moreover, among the identified polypeptides, five of them were similar to heat shock proteins: endoplasmin (Grp94); heat shock protein 90 kDa (HSP90); 78‐kDa glucose‐regulated protein (Grp78); chain A, the crystal structure of the human HSP70 ATPase domain and heat shock protein beta‐1 isoform X. The concentrations of the analysed polypeptides, expressed in optical density units (ODU), differed significantly (p ≤ .05) across the examined periods of the reproductive season. The highest ODU values for almost all analysed proteins were observed during the rutting period. The presence of HSPs in the epididymal tissues and fluids of roe deer in different periods of the reproductive season could indicate that those proteins play an important role in sperm maturation in the epididymis.  相似文献   
80.
Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservation ex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallus L.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 106 per ml to 3520 × 106 per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that for AI purposes, the ejaculate quality has to be at minimum 10 SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons.  相似文献   
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