首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   111篇
  免费   12篇
林业   1篇
综合类   11篇
农作物   2篇
水产渔业   1篇
畜牧兽医   104篇
植物保护   4篇
  2023年   1篇
  2021年   1篇
  2019年   1篇
  2018年   2篇
  2017年   4篇
  2016年   6篇
  2015年   1篇
  2014年   8篇
  2013年   31篇
  2012年   1篇
  2011年   2篇
  2010年   11篇
  2009年   5篇
  2008年   1篇
  2007年   1篇
  2006年   3篇
  2005年   5篇
  2003年   1篇
  2002年   3篇
  2001年   1篇
  2000年   2篇
  1999年   1篇
  1998年   8篇
  1997年   3篇
  1996年   3篇
  1995年   5篇
  1994年   1篇
  1993年   7篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
排序方式: 共有123条查询结果,搜索用时 15 毫秒
101.
Cell cycle stage and synchronization of donor cells are important factors influencing the success of somatic cell nuclear transfer. This study examined whether serum starvation has any effect on specific cell death. We also studied the effects of serum starvation, culture to confluence, and full confluency (confluent + 72 h) on cell cycle characteristics and apoptosis of goat dermal fibroblast cells. The cells were obtained from the ear of a 1.5‐year‐old female goat. The following experimental groups were analysed for fibroblast cells: (i) normally growing, (ii) confluent, (iii) full confluency, (iv) cells starved for 48 h and (v) cells starved for 72 h. Analysis of cell cycle distribution by flow cytometry showed that 4.56 and 51.88% of normal cycling cells were at the G0 and G1 phases respectively. In the confluent group, 80% of the cells were arrested in the G0/G1 phase. Serum starvation for 48 and 72 h arrested 84.78% and 90.1% cells at the G0/G1 phase respectively which showed a significant difference when compared with the control group (p < 0.05). Double staining by PI and FITC distinguishes G0 phase from G1 phase. In the full confluency group, 91.53% of cells were at G0/G1 stage, but in contrast to the serum starved group, this high percentage of G0/G1 cells was mainly associated with G1 cells. Under normal culture conditions, 6.39% of cells underwent early apoptosis. In the confluent group 8.93% of cells showed early apoptosis. Serum starvation for 48 and 72 h caused early apoptosis in 8.91 and 39.83% of the cells respectively. Full confluency treatment did not increase the number of apoptotic cells significantly (8.67%). After 72 h, serum starvation significantly increased early apoptosis (p < 0.05). In conclusion, the use of full confluency is suitable for cell cycle synchronization because it arrests cells at the G0/G1 phase and also induces less apoptosis in comparison with the serum starvation group.  相似文献   
102.
103.
ObjectiveTo evaluate the analgesic efficacy and safety of tumescent local anesthesia (TLA) in cats undergoing unilateral mastectomy.Study designProspective clinical trial.AnimalsA total of 12 ovariohysterectomized female cats.MethodsAll animals were premedicated with pethidine (4 mg kg–1) intramuscularly (IM), followed by induction of anesthesia with propofol (5 mg kg–1) intravenously and maintenance with isoflurane in oxygen. A refrigerated TLA solution (15 mL kg–1, 8 °C) was injected using a Klein cannula. The solution was composed of 0.5 mL of epinephrine (1 mg mL–1) and 40 mL of 2% lidocaine added to 210 mL lactated Ringer’s solution (final lidocaine concentration 0.32%). Heart and respiratory rates, systolic arterial blood pressure, temperature and oxygen saturation were measured during anesthesia. Blood samples were collected from the jugular vein for measurement of plasma lidocaine concentration using high performance liquid chromatography. Postoperative pain scores were evaluated hourly for 6 hours. Analgesic rescue was performed with tramadol (2 mg kg–1) IM and meloxicam (0.15 mg kg–1) subcutaneously.ResultsPlasma lidocaine concentration peaked at 90 minutes after injection of TLA, but no concentration considered toxic for the species was measured. The median postoperative analgesia time was 6 hours after injection of TLA.ConclusionsThis study found that TLA prevented sympathetic response to noxious stimuli during anesthesia and provided satisfactory postoperative analgesia in cats submitted to total unilateral mastectomy, with no apparent signs of toxicity.Clinical relevanceTLA can prevent sympathetic stimulation resulting from noxious stimuli during anesthesia, promoting good intraoperative conditions, proving to be a viable addition to analgesia in cats submitted to a total unilateral mastectomy.  相似文献   
104.
The objective of the study was to assess apoptosis and DNA defragmentation in equine semen diluted and chilled to +4°C. Semen was collected from nine fertile stallions, including four Arabian thoroughbreds and five coldbloods. Examinations were carried out immediately after semen collection (0) and at five storage times (24, 48, 72, 96 and 120 h). The basic semen evaluation was performed in terms of volume, sperm concentration, viable sperm percentage, progressive motility and morphology. Using flow cytometry, DNA defragmentation and cell membrane integrity of spermatozoa were determined. The results of basic tests did not demonstrate significant differences amongst stallions, except for progressive sperm motility, which was significantly higher (p < 0.05) in the semen of Arabian stallions. In the semen of the same stallions, a significant decrease in the percentage of alive spermatozoa was observed at 72, 96 and 120 h of storage, whereas a significant increase in the number of spermatozoa with DNA defragmentation was found after 24 h storage. In the semen of coldblood stallions, significantly reduced live spermatozoa percentage was observed at 96 and 120 h, while increased DNA defragmentation was observed at 48 h. These findings demonstrated that the semen of Arabian stallions chilled to +4°C retained original characteristics until 24 h of storage, whereas in coldbloods, these were preserved up to 48 h of storage.  相似文献   
105.
When Bill Manktelow died at his home in his 74th year on the 3rd of May, the veterinary profession lost a major figure whose work over 50 years has influenced many people in all branches of the profession.  相似文献   
106.
Several methods are used to measure lipid peroxidation (LPO) in spermatozoa. The objective of this study was comparing the thiobarbituric acid reactive species (TBARS) method and the BODIPY 581/591 C11 (B581) and BODIPY 665/676 C11 (B665) fluorescent probes to measure induced peroxidative damage in thawed epididymal spermatozoa from Iberian red deer. Samples from three males were thawed, pooled, diluted in PBS, incubated at room temperature and assessed at 0, 3, 6 and 24 h under different experimental conditions: Control, hydrogen peroxide (H2O2) 0.1 mm or 1 mm , or tert‐butyl hydroperoxide (TBH) 0.1 mm or 1 mm . LPO was assessed by the TBARS assay [malondialdehyde (MDA) detection] and by the fluorescence probes B581 and B665 (microplate fluorimeter and flow cytometry). Increasing MDA levels were only detectable at 1 mm of TBH or H2O2. Both fluorescence probes, measured with fluorometer, detected significant increases of LPO with time in all treatments, except Control. Flow cytometry allowed for higher sensitivity, with both probes showing a significant linear relationship of increasing LPO with time for all oxidizing treatments (p < 0.001). All methods showed a good agreement, except TBARS, and flow cytometry showed the highest repeatability. Our results show that both B581 and B665 might be used for LPO analysis in Iberian red deer epididymal spermatozoa, together with fluorometry or flow cytometry. Yet, the TBARS method offered comparatively limited sensitivity, and further research must determine the source of that limitation.  相似文献   
107.
108.
109.
110.
SUMMARY Sterile guarded swabs were used to sample the anterior vaginal and cervical area of 23 normal healthy sows during various stages of the reproductive cycle. The samples were collected one week before farrowing, within 24 hours of farrowing, weekly up to weaning, at mating and at 2 and 3 weeks after mating, and then plated and incubated aerobically and anaerobically. At least one positive sample was obtained from each sow and at each stage of the reproductive cycle. Most positive samples (78.3%) were obtained on the day of farrowing and the least 3 weeks after mating (19.0%). The second highest number of positive samples (45.5%) was found immediately after mating. Although there was no significant difference among sows of different parities, there was a trend for older sows to have more positive samples after farrowing (84.6%). There was a greater decrease in positive samples after farrowing and after mating among younger sows compared with older sows. A wide range of bacteria including aerobic and anaerobic species, were recovered from 142 Isolates. The more representative bacteria were Streptococcus spp (23.2%); Escherichia coll (22.5%); Staphylococcus spp (19.0%) and Corynebacterium spp (13.4%). Of the cultures, 54.7% were pure and 45.3% were mixed. Both the percentage of bacterial isolates as well as the type of culture (pure or mixed) were similar to those frequently reported in clinical cases of vulval discharge syndrome. The results indicate that sows usually develop infections of the reproductive tract at farrowing and mating but these infections do not normally persist.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号