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1.
This study was conducted to determine whether the seasonal delay in puberty in autumn is driven by individual differences in night-time melatonin secretion in domestic gilts at the attainment of puberty. A group of spring-born gilts (n = 30) were expected to reach puberty in autumn by the age of 7 months. Eighteen of these gilts were selected in pairs on the basis of matched days of birth. By the expected time, half of the animals showed oestrous symptoms (group CYCLING, n = 9) with the rest remaining silent (group SILENT, n = 9). Afterwards, all gilts were fitted with indwelling jugular catheters for frequent blood sampling. Blood samples were collected from all animals three times during the day followed by three times in the night at 2-h intervals for 48 h. The samples were analysed by a commercial radioimmunoassay (RIA). The results show a consistent 25-fold rise (on average) in night-time melatonin concentration in every animal sampled with group averages ranging from 0.28 +/- 0.04 to 0.37 +/- 0.06 pg/ml at day and from 10.20 +/- 2.16 to 10.67 +/- 0.05 pg/ml at night. Night-time group mean values between CYCLING and SILENT gilts did not differ significantly (10.26 +/- 0.67 and 10.38 +/- 0.94 for the CYCLING; 10.67 +/- 0.05 and 10.20 +/- 2.16 for the SILENT). When 10 pg/ml was used as a threshold value, six individuals did not reach it during the night (low responders). Two of these gilts were CYCLING and four were SILENT. In conclusion, the results presented imply no involvement of the level of night-time melatonin concentration in the seasonal delay of puberty in gilts.  相似文献   
2.
The effect of vulvar discharge syndrome (VDS) on sow and gilt fertility was studied on 26 farms. Of 824 animals inspected in 21 randomly selected and five VDS problem farms, 19 (2.3%) were afflicted with VDS. Altogether 542/799 of the examined animals (67.8%) farrowed thereafter. Nine of the 19 VDS animals (47.4%) and 533/780 non-VDS animals (68.3%) farrowed at the first chance after the examination (p = 0.05). None of the unmated gilts in this study had VDS. Environmental and individual factors likely to be associated with fertility and VDS were tested. In multivariate analysis, factors associated with farrowing were VDS, reproductive status, availability of roughage and confinement to individual stalls. None of the variables tested was associated with VDS. However, all of the VDS problem farms were overcrowded and had concrete, partly slatted floors with little or no bedding. The median value of haptoglobin (Hp) was 2.5 (range 1.3-3.1) g/l in VDS animals and 2.3 (0.5-4.3) g/l in controls (p = 0.6). The median C-reactive protein (CRP) in VDS animals was 30.3 (3.3-171.3) mg/l and in controls 25.9 (3.3-361.1) mg/l (p = 0.7). In conclusion, VDS decreased fertility of gilts and sows in the absence of a systemic acute-phase response, as indicated by stable concentrations of Hp and CRP.  相似文献   
3.
Comparison was made of the holding power of 5.5 and 4.5 mm cortical orthopedic screws inserted into third metacarpal and metatarsal cadaver bones from 3- and 8-year-old horses. The tensile strength of these screws was tested mechanically. In nine comparative trials of these screws, 5.5 mm screws pulled out of bone in five trials at an average of 116.0 kg tensile force and broke in four trials at an average of 1383.2 kg. A 4.5 mm screw pulled out of bone at 834.5 kg in one trial, and screws broke at an average of 849.2 kg in eight trials. The larger 5.5 mm screw required a significantly greater (p = 0.022) pullout force than the mean force at 4.5 mm screw breakage. Fixation failure was due to screw breakage or bone shear, with 5.5 mm screws occasionally creating bone fragmentation during pullout. The average tensile breaking strengths of the 5.5 mm screws (1391.4 kg) and 4.5 mm screws (832.7 kg) determined mechanically were similar to forces at screw breakage during pullout testing in bone. Since the 5.5 mm screws have greater holding power and tensile strength than 4.5 mm screws, the use of the 5.5 mm screw in fracture repair in adult horses is recommended.  相似文献   
4.
5.
Objectives To assess a method for monitoring depth of anaesthesia using components of middle latency auditory evoked potential (AEP) waveforms during anaesthesia with fentanyl/fluanisone and midazolam. Study design Prospective observational study. Animals Five female Wistar rats weighing between 210 and 250 g. Methods Implanted electrodes were used to record AEPs in animals receiving five doses of anaesthetic. Recordings were made at 5 minutes post‐injection (deep anaesthesia; no pedal withdrawal response, PWR) and then at 25 minutes (light anaesthesia; strong PWR). Responses showed five characteristic peaks occurring at 11, 14, 23, 42 and 68 ms that were measured for latency of occurrence and peak amplitude. Results Auditory evoked potential peaks P14, N23 and P42 were increased significantly in latency with successive anaesthetic injections [avg. F(1,4) = 12.53, p < 0.001; avg. F(1,4) = 10.6, p < 0.001; avg. F(1,4) = 3.9, p = 0.02, respectively]. Peak N23 showed a significant reduction in latency during the 20 minute recovery period following both the first and second anaesthetic injections (t(3) = 7.52, p = 0.005; t(4) = 5.17, p = 0.007, respectively). Peak P42 occurred significantly earlier 20 minutes following the second anaesthetic injection (t(4) = 4.75, p = 0.009). The mean overall depth of anaesthesia assessed using PWR scores was significantly correlated with the mean latency of peak N23, such that as the strength of PWR increased, N23 occurred significantly earlier (r = ?0.99, p = 0.01). The amplitude difference between peaks N23 and P42 increased after the second and third drug administrations [avg. F(1,4) = 10.65, p = 0.031 and avg. F(1,4) = 11.24, p = 0.028, respectively]. Conclusion The characteristics of these peaks, and in particular latency of peak N23, may provide a useful tool for assessing depth of anaesthesia produced by this, and possibly other anaesthetic agents.  相似文献   
6.

Background

Due to numerous complications associated to gastrointestinal augmented cystoplasty, this study aimed to analyze the anatomic repair of the bladder of 10 female dogs using grafts of porcine small intestinal submucosa (SIS) seeded with cultured homologous smooth muscle cells, and compare them with the acellular SIS grafts.

Results

We assessed the possible side effects and complications of each type of graft by clinical examination, abdominal ultrasound and laboratory findings. Anatomic repair of neoformed bladder was assessed by histological staining for H/E and Masson''s Trichrome, analyzed with a Nikon Photomicroscope connected to the system of image analysis Image J.

Conclusions

We propose that SIS associated to homologous smooth cells can improve the quality of tissue repair, and consequently decrease the potential complications inherent to acellular SIS.  相似文献   
7.
8.
Sixty-eight cases of cortical bone sequestration in 67 equine patients were reviewed with regard to the clinical presentation, method of treatment, and outcome. All lesions were located in skeletal areas with minimal soft tissue coverage, with 53% of them in the metatarsal and metacarpal bones. At the time of admission, 60% of the patients with limb lesions were lame; the majority improved with therapy. After sequestrectomy, there was a trend for surgical wounds which could be managed by primary closure to heal more rapidly (3.8 weeks) than wounds which required second intention healing (6.4 weeks). The appearance of healed wounds, as evaluated by owners, was acceptable in 45 cases. Dissatisfaction with the appearance of the healed wounds in 22 cases suggested a need to address the issue of cosmetic results.  相似文献   
9.
The holding power of orthopedic screws in the third metacarpal and metatarsal cadaver bones of foals that were aged from 1 to 14 days was tested. Comparative trials between screws inserted at the same site in contralateral bones from the same foal were performed to compare the holding power of 5.5 mm cortical and 6.5 mm cancellous screws in the metaphysis, and the holding power of 5.5 and 4.5 mm cortical screws in the diaphysis. A MTS servohydraulic tensile testing machine was used to perform screw pullouts at a displacement rate of 19 mm/sec. There was no significant difference between maximum holding power of 5.5 mm cortical screws and 6.5 mm cancellous screws in the metaphysis when expressed as kg per mm of bone width at the screw insertion site (p = 0.097) or as kg per mm of screw thread engaged in the bone (p = 0.17). There was no significant difference in holding power of 5.5 and 6.5 mm screws in the proximal versus distal metaphysis (p = 0.10). The 5.5 mm screws had significantly greater holding power than the 4.5 mm screws in the diaphysis (p = 0.0097). Fixation failure at screw pullout was always due to bone shear. In internal fixation in foal bone, the 5.5 mm screws may be a suitable alternative to 6.5 mm screws in the metaphysis. Use of 5.5 mm rather than 4.5 mm screws is recommended in the diaphysis because of greater holding power.  相似文献   
10.
The Iberian lynx is considered the most endangered felid species. Therefore, an ex situ conservation program was initiated to protect this species from extinction. Additional knowledge on lynx reproduction biology and reliable methods for reproductive monitoring are important for developing a captive breeding program. The aim of this study in lynx was to implement transrectal ultrasonography to visualize ovarian structures (follicles, corpora lutea) and to assess ovarian activity in addition to analysis of serum progesterone and oestradiol. Because of limited access to Iberian lynxes, the less-endangered Eurasian lynx and bobcat were also studied in this comparative study. Recent endocrinological studies based on faecal and urinary progesterone and oestrogen metabolites revealed that steroid profiles in both these species were alike and did not follow the typical pattern of other felids. Pregnancy diagnosis was not possible, since progesterone concentrations did not differ between pregnant and pseudopregnant animals. Progesterone was also detected after parturition as well as after weaning until the onset of a new oestrous cycle. In the present study, the presence of corpora lutea during the non-breeding season was confirmed by ultrasonography and by elevated serum levels of progesterone averaging 3.56 ± 1.3 ng/ml in Eurasian and 6.1 ± 0.26 ng/ml in Iberian lynx, respectively. The ultrasonographical findings on the ovarian structures suggest strongly that corpora lutea developed after ovulation stay active until November and regress before the onset of the next oestrus.  相似文献   
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