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41.
1. A non-invasive condenser microphone was used to detect cardiogenic, acoustic pressure changes (acoustocardiogram, ACG) over the eggshell in order to determine embryonic heart rate (HR) of ostriches in a commercial hatchery. 2. HR measured for 36 eggs at 36.3C was maintained at about 185 bpm during the middle stage of development (days 19 to 23) and then decreased with embryonic development. 3. The daily changes in HR were not related to egg mass, but HR of high water vapour conductance (GspH2O) eggs was found to decrease less during the last stages of incubation relative to low and medium GspH2O groups. 4. The averaged HR at 80% of incubation period was close to the value predicted from the allometric equation determined previously for embryos of domesticated precocial birds.  相似文献   
42.
Effects of a short-term hyper- and hypoprolactinaemia on serum concentrations of LH, testosterone and semen quality in six male Beagles were investigated. Blood samples were collected at 3-day intervals for 12 weeks. The time span was divided into five 3-week periods: pre-treatment, metoclopramide (MCP) treatment (0.2 mg/kg orally three times daily), cabergoline (CAB) treatment (5 μg/kg orally once daily), post-treatment 1 and post-treatment 2. In the latter, only semen characteristics were evaluated. Semen parameters were analyzed once per week during the whole 15-week investigation time. At the end of each period, the effects of a single intravenous injection of thyrotropin-releasing hormone (TRH; 10 μg/kg) on the secretion of prolactin (PRL), LH, testosterone, thyroid-stimulating hormone and thyroxine (T4) were investigated. Pre-treatment serum PRL concentration increased under MCP (p < 0.05), followed by a decrease under CAB administration (p < 0.05). Luteinizing hormone and testosterone concentrations were not affected. Except for straight-line sperm velocity, semen quality did not differ between collection periods. A single iv TRH injection induced a significant PRL increase at 20 min in all experimental periods except during CAB treatment. Luteinizing hormone and testosterone did not show clear TRH-related changes. Basic T4 levels were significantly reduced after CAB treatment (p < 0.05). The results of the present study demonstrate that MCP-induced short-term hyperprolactinaemia in male beagles does not seriously affect the hypothalamo-pituitary axis and semen quality.  相似文献   
43.
In the last 21/2 years, 288 grey parrot and amazon species with symptoms of respiratory disease clinically were presented to the clinic for avian medicine at the Justus-Liebig-University in Giessen. Ventro-dorsal and latero-lateral radiographs were taken from all birds; radiologic signs of lower respiratory tract disease were noted. Radiographs were normal in 55 of the birds. The results of the radiographic examination for the remaining 233 birds were compared with the necropsy results of terminally ill parrots, with the results of laboratory examinations/endoscopy/and/or with an examination by computed tomography. Thoracic radiographs were evaluated for occurring radiological abnormalities pertaining to the respiratory tract. The frequency of these lesions and their association with a disease process and/or specific etiology was noted.  相似文献   
44.
Two vaccines, based on formalin-killed whole cells of toxigenic Pasteurella multocida type D and Bordetella bronchiseptica combined with a partially toxoided cell extract of P multocida, were prepared with Freund's incomplete adjuvant (vaccine 1) or by alum precipitation (vaccine 2). Each was tested for safety and efficacy in reducing the severity of nasal turbinate atrophy and improving the growth rate of pigs in three Western Australian commercial piggeries with endemic atrophic rhinitis. In safety experiments with vaccine 1, no adverse clinical effects were observed in vaccinated sows or their progeny. Piglets receiving vaccine 2 showed no injection site abnormalities, pyrexia or turbinate atrophy. In field trials, vaccine 1 significantly reduced the prevalence of moderate to severe nasal turbinate atrophy (Done score 3 to 5) when used in two piggeries (A and B). Progeny from vaccinated sows in piggery B also grew significantly faster than controls. When vaccine 2 was used in piggery A at a later date and in another piggery (C), growth rate was not improved in either piggery and the prevalence of moderate to severe turbinate atrophy was reduced only in piggery C.  相似文献   
45.
AIMS: To report on the long-term outcomes of hydraulic artificial urethral sphincter (HAUS) placement for the correction of urethral sphincter mechanism incompetence (USMI) in New Zealand dogs.

METHODS: Retrospective data were obtained from cases of dogs which had a HAUS placed after failed medical and/or surgical management of USMI between August 2012 and November 2016. Owner assessment of urinary incontinence was evaluated by an online survey in May 2017 using a visual analogue scale (0 being normal, 100 being severely affected) for the frequency, volume and severity of any straining to urinate, immediately prior to the placement of the HAUS and at the time of the survey. The number of days between surgery and the completion of survey were recorded.

RESULTS: Seven females and two male dogs, which were all desexed except for one female, were eligible for inclusion in the study. The period of follow-up following HAUS placement ranged from 206–1,685 days. Following HAUS placement, frequency and volume of urinary incontinence decreased for six dogs and were practically unchanged for three dogs. The median frequency score decreased from 70 to 13 and the volume score decreased from 73 to 12. There was no consistent change in the perceived degree of straining to urinate. Complications occurred in three dogs; one required repositioning of a dislodged injection port, one required management for haematuria and a hypoplastic bladder, and one required surgical removal of fibrous tissue around the HAUS cuff.

CONCLUSIONS AND CLINICAL RELEVENCE: HAUS placement was an effective method for the treatment of persistent USMI in most dogs and provided good clinical results based on owner assessment. The technique was associated with few complications and allowed successful long-term control of urinary incontinence without the need for medical management.  相似文献   

46.
Abstract

CASE HISTORY: Ovariohysterectomy was performed on an adult Cavalier King Charles Spaniel. The skin that had been clipped for surgery was noticed to be erythematous 8 days later.

CLINICAL AND PATHOLOGICAL FINDINGS: Poorly defined patches containing multiple papules were visible bilaterally within the clipped skin. These became larger over the following 2 weeks, and samples were collected for histology. Seven days later, the lesions were multiple raised masses, up to 5 cm in diameter. Histology revealed numerous cup-shaped epidermal proliferations extending into the dermis. The presence of keratinocytes with increased quantities of blue-grey cytoplasm, and koilocytosis suggested papillomavirul infection; Canis familiaris papillomavirus (CfPV-2) DNA was amplified from two separate samples. Complete regression was observed 8 weeks after the lesions had been initially observed.

DIAGNOSIS: Multiple inverted papilloma confined to skin that had been clipped for surgery.

CLINICAL RELEVANCE: This is the first time that the development of canine cutaneous papillomas has been associated with surgery. The nature of the association between surgery and development of the papillomas is uncertain. However, it is possible that damage to superficial skin could promote the formation of papillomas. This is the first identification of CfPV-2 in New Zealand.  相似文献   
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49.
Natural transmission of bovine leukaemia virus (BLV) infection in south-eastern Queensland dairy herds was slow in 2 herds with a low to moderate (13 to 22%) prevalence of infection. Infection spread much more rapidly in a herd that had a higher prevalence (42%) when first tested. In a 13 month study of this herd, the cumulative incidence of infection was 24%. In one herd new infections were confined almost entirely to calves of uninfected dams. Following the end of feeding bulk milk to calves, a common practice in dairy herds, no more calves in this herd became infected. In laboratory experiments, neither prolonged housing of susceptible calves with infected cattle, consumption of drinking water contaminated with infected blood, nor inoculation of sheep with saliva from infected cattle resulted in transmission of BLV infection. Sheep were infected by subcutaneous inoculation of a suspension of purified lymphocytes from an infected heifer. The minimum infective dose was 10(3) lymphocytes, equivalent to the number of lymphocytes in approximately 0.1 microliter blood. Thus, procedures involving the transfer of a very small volume of blood from animal-to-animal have the potential to transmit infection.  相似文献   
50.
This study aimed to evaluate various concentrations of egg yolk (5, 10, or 20%) in combination with different concentrations of glycerol (3% or 6%) added to a Tris‐based extender on the post‐thaw characteristics of sperm obtained from Tayassu tajacu. For this purpose, semen from 10 sexually male mature collared peccaries was collected by electroejaculation and evaluated for sperm motility, vigour, viability, morphology and functional membrane integrity. The ejaculates were initially extended in Tris‐fructose plus egg yolk (5%, 10% or 20%). After cooling, the semen was added to Tris‐egg yolk plus glycerol (6% or 12%), resulting in a final concentration of 3% or 6% glycerol of the extender. Straws were frozen using liquid nitrogen and thawed in a water bath at 37°C for 30 s. The frozen–thawed semen was evaluated as reported for fresh semen. After thawing, a significant decrease was verified for sperm motility and vigour, for all the samples in comparison with fresh semen. However, no differences were evidenced among treatments for any sperm characteristics evaluated (p > 0.05), except for the combination between 10% egg yolk and 6% glycerol, which provided the worst preservation of functional membrane integrity (p < 0.05). The interactions between higher concentrations of egg yolk (20%) and glycerol (6%) and also between lower concentrations of the same substances (5% egg yolk and 3% glycerol) added to the Tris‐based extender negatively affected the preservation of the normal sperm morphology after thawing (p < 0.05). In conclusion, the use of Tris‐based extender added to 10% or 20% egg yolk plus 3% glycerol is recommended for effective sperm cryopreservation in collared peccaries.  相似文献   
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