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   40篇
  免费   4篇
林业   3篇
农学   1篇
  8篇
综合类   1篇
农作物   9篇
水产渔业   6篇
畜牧兽医   11篇
园艺   2篇
植物保护   3篇
  2022年   2篇
  2021年   1篇
  2020年   1篇
  2019年   1篇
  2018年   5篇
  2017年   2篇
  2016年   1篇
  2015年   2篇
  2014年   2篇
  2013年   3篇
  2012年   1篇
  2010年   4篇
  2009年   2篇
  2008年   7篇
  2007年   3篇
  2006年   1篇
  2005年   3篇
  2002年   1篇
  2001年   1篇
  1969年   1篇
排序方式: 共有44条查询结果,搜索用时 448 毫秒
11.
1. A 6-week study was conducted to investigate the effects of phytase and hydroalcoholic extract of Withania somnifera root (WS) on productive performance and bone mineralisation of laying hens in the late phase of production.

2. Diets were arranged factorially (3?×?2?×?2) and consisted of a positive control with adequate Ca (4·37%) and nonphytate P (NPP; 0·39%) and a negative control diet with Ca (4·06%) and NPP (0·36 %); three concentrations of Withania somnifera (0, 65 and 130?mg/kg diet); and two concentrations of microbial phytase (0 and 300 U/kg diet).

3. A total of 144 72-week-old Hy-Line W36 laying hens were randomly assigned to the 12 treatment groups. Each treatment was replicated 4 times (4 x 3 hens). Egg production and egg weight were recorded daily, while feed intake and egg quality traits were recorded every two weeks. Bone quality traits were evaluated at the end of experiment.

4. Withania somnifera supplementation increased egg production and lowered egg weight only in the second two weeks of the experiment. Addition of phytase significantly depressed specific gravity of the eggs for the entire experiment period. No dietary treatment effects were observed on egg shell thickness and yolk weight.

5. Withania somnifera at 130?mg/kg did not affect feed intake. The hens fed on the positive control diet had higher albumen weight than the negative control diet in the second two-week period. Supplementation of the positive control diet with 65?mg/kg Withania somnifera in the absence of phytase significantly improved shell weight compared with the negative control (5·779 vs. 5·273?g respectively).

6. Supplementing Withania somnifera significantly improved Ca and P retention in tibia bone. In addition, an increase in tibia bone P was observed with phytase supplementation. There were significant interactions between Withania somnifera content and phytase for tibia bone Ca and P.

7. The results of this experiment indicated that dietary Withania somnifera has beneficial effects on tibia bone Ca and P content, and phytase improved tibia bone P retention without adverse effects on productive performance.  相似文献   
12.
Eimeria species from poultry breeder farms without previous exposure to anticoccidial vaccines in five distinct geographical regions of Iran were examined for genetic relatedness by the random amplified polymorphic DNA (RAPD) assay. Eight different oligonucleotide decamers with arbitrary DNA sequences were tested as primers to amplify DNA from five isolates of each E. acervulina, E. tenella, and E. maxima. Depending on the species/isolate-primer combination, between 1 and 14 DNA fragments ranging in size from 240 to 3000 bp were amplified. The two isolates originated from Northeast and North parts of Iran showed minor differences and two isolates originated from Northeast and Southwest of Iran showed major differences in their amplified DNA patterns. The intra-specific similarity coefficient within five isolates of each species of, E. acervulina, E. tenella, E. maxima was 74, 82 and 72%, respectively. The distance indices observed between species were greater than those found between isolates (80-90%) with all examined primers. The inferred phylogenetic tree on the fingerprinting of all species revealed that the RAPD-PCR can easily differentiate within and between species and could be a useful and valuable tool in future epidemiological studies, designing and developing of vaccines against avian coccidosis, here in Iran and neighboring countries.  相似文献   
13.
14.
It has been hypothesized that pain originating from the dorsal margin of the sole of the hoof in horses can be attenuated by analgesia of either the distal interphalangeal (DIP) joint, or of the navicular bursa (NB). To test this hypothesis, an experimental lameness was induced in the toe region of the left forelimb in six adult horses. After this, both synovial structures were blocked and the effects on the lameness were semi-quantitatively scored. Lameness was induced by creating pressure on the dorsal margin of the sole with the help of set-screws that were screwed into a nut, welded to the inside of each branch of the shoe. Gaits were recorded on a videotape before and after application of the screws, and after application of either a local anaesthetic or saline into the DIP joint or NB. The gaits were independently evaluated by two blinded clinicians and scored. Lameness scores were high after application of the screws and remained high after the administration of saline, but decreased significantly (P < 0.05) after administration of the local anaesthetic. Analgesia of the DIP joint as well as the NB appeared to be able to desensitize a portion of the sole. It was concluded that pain arising from the toe region of the sole should not be excluded as a cause of lameness when lameness is attenuated by analgesia of the DIP joint, or of the NB.  相似文献   
15.
M. Mardi    L. Pazouki    H. Delavar    M. B. Kazemi    B. Ghareyazie    B. Steiner    R. Nolz    M. Lemmens    H. Buerstmayr 《Plant Breeding》2006,125(4):313-317
Fusarium head blight (FHB or head scab) has become a major limiting factor for sustainable wheat (Triticum aestivum L.) production around the world. For quantitative trait loci (QTL) analysis of resistance to FHB, F3 plants and F3 : 5 lines, derived from a ‘Frontana’ (moderately resistant)/‘Seri82’ (susceptible) cross, were spray‐inoculated in 2001 and 2002, respectively. Artificial inoculations were carried out under field conditions. Of 273 SSR and AFLP markers, 250 could be mapped and they yielded 42 linkage groups, covering a genetic distance of 1931 cM. QTL analysis was based on the constructed linkage map and area under the disease progress curve (AUDPC). The analyses revealed three consistent QTLs associated with FHB resistance on chromosomes 1BL, 3AL and 7AS explaining 7.9%, 7.7% and 7.6% of the phenotypic variation, respectively, above 2 years. The results confirmed the previously described resistance QTL of ‘Frontana’ on chromosome 3AL. A combination of ‘Frontana’ resistance with ‘Sumai‐3’ resistance may lead to lines with augmented resistance expression.  相似文献   
16.
The physiological condition in fishes required for their selection as broodfish can be determined by hematological studies. The present study aims at examining the hematological indices in juvenile sturgeons at different stages of growth. The main blood features, such as total albumin content in blood, hemoglobin concentration and the erythrocyte and leukocyte count, were measured in a total of 54 specimens of 1-, 2- and 6-year old sturgeon (Persian sturgeon Acipenser persicus and beluga Huso huso), artificially produced at the Shahid Dr. Beheshti Fish Breeding and Rearing Center located in the Gilan Province.In the Persian sturgeon specimens studied, the total albumin concentration in the blood increased from 26.05 to 52.50 g l–1, the hemoglobin concentration increased from 42.2 to 65.8 g l–1, the erythrocyte count increased from 240 to 452.5 thousand cell ml–1 and the leukocyte count increased from 13.43 to 46.48 thousand cells ml–1. The total leukocyte was composed of 73.25 to 82.70% lymphocytes, 12.3 to 20% neutrophils, 2.25 to 6.50% eosinophils and 0.2 to 2.5% monocytes.In the beluga specimens studied, the total albumin concentration in the blood increased from 20.05 to 42.20 g l–1, the hemoglobin concentration increased from 46.3 to 78.6 g l–1, the erythrocyte count increased from 495 to 735 thousand cells ml–1 and the leukocyte count increased from 31.6 to 57.7 thousand cells ml–1. The total leukocyte was composed of 54.5 to 67.5% lymphocytes, 22.63 to 33.86% neutrophils, 6.60 to 13.7% eosinophils and 0.6 to 2.25% monocytes.This research reveals the trends of some hematological features during the growth and development of sturgeons in the South Caspian Sea, reared in artificial conditions. It shows that with the increase in age, the hematological indices also increased.  相似文献   
17.
18.
Performance and clinical characteristics of a novel hyperthermia antenna operating at 434 MHz were evaluated for the adjuvant treatment of locally advanced superficial tumours in cats, dogs and horses. Electromagnetic simulations were performed to determine electric field characteristics and compared to simulations for a flat microwave antenna with similar dimensions. Simulation results show a reduced skin surface and backfield irradiation and improved directional irradiation (at broadside) compared to a flat antenna. Radiated power and penetration is notably increased with a penetration depth of 4.59 cm compared to 2.74 cm for the flat antenna. Clinical use of the antenna was then evaluated in six animals with locoregionally advanced solid tumours receiving adjuvant chemotherapy. During clinical applications, therapeutic temperatures were achieved at depths ≥4 cm. Objective responses were seen in all patients; tissue toxicity in one case limited further therapy. This antenna provides compact, efficient, focused and deep‐penetrating clinical hyperthermia for the treatment of solid tumours in veterinary patients.  相似文献   
19.
Despite a large number of investigations on the molecular genetics and population structure of the whitefly Bemisia tabaci (Gennadius) complex, no such study had been conducted in Iran. The genetic variation of B. tabaci was examined using polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) for 18 field collections from cucumber, eggplant, and tomato in four provinces of Iran. PCR amplification and restriction digestion with two enzymes detected 388 RFLP fragments, of which 16 fragments showed polymorphisms. Cluster analysis of these data placed all B. tabaci individuals within a single group, and there was no evidence for between- or within-population genetic variation. Phylogenetic (Clustal W) analysis of 42 B. tabaci mtCOI sequences (n = 21 field collections) from Iran, and a comparison with well-studied haplotype or biotype reference sequences available in public sequence databases, revealed that the Iranian B. tabaci populations were most closely related to the B biotype at 0–1.2% nucleotide identity. The B biotype is a well-known member of a sister clade from the Middle East–North African region of the world, owing to its nearly worldwide distribution and invasive characteristics. This report indicates that a single major haplotype of B biotype is prevalent in Iran and that its closest relative is the B biotype. Also, given the extent of known variation in the Middle East and African continent, data indicate somewhat surprisingly that the B. tabaci collections sampled in Iran had limited genetic variation and population substructure. Knowledge that the B biotype of B. tabaci predominates in Iran is important for designing effective pest management strategies given that biotypes of B. tabaci are known to differ greatly with respect to insecticide resistance, host range, virus–vector interactions, and other key biological characteristics.  相似文献   
20.
This research was aimed to investigate the prevalence and clinical impact of occult HBV infection in thalassemic patients with chronic HCV infection. In this cross-sectional study we have totally examined 60 patients suffering HBV and HCV infections by PCR and RT-PCR methods, respectively, in Kerman province of Iran. ELISA technique (RADIM, Italy) was used to detect anti-HBc, anti-HBs and HBsAg. The serum level of liver enzymes (SGOT, SGPT, DB, TB and ALK) were analyzed in the HCV infected patients (MAN, IRAN). Statistical analyses performed using t-test and Chi-square. We found that 27 cases (out of 60) were infected by HCV but HBV-DNA was not seen in HCV infected patients. Present findings also showed that none of samples were HBsAg positive but 9 (33%) (out of 27) HCV-RNA positive patients were anti-HBc positive and 11 (40.7%) were positive for anti-HBs. We found that SGOT, SGPT, DB, TB and ALK are above normal in 27 (100%), 19(70.3%), 12(44.5%), 15 (55.5%) and 15 (55.5%) RNA-HCV positive patients, respectively. The prevalence of hepatitis C infection is very high in thalassemic patients and based on other studies our results showed that the prevalence of HCV infection in Kerman is more than other provinces of Iran. In contrast with other studies HBV-DNA in these patients could not be detected, hence, it seems that occult HBV infection isn't frequent in Iranian thalassemic patients who suffering from chronic HCV infection.  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