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1.
1. Tetracycline resistance determinants are widespread among bacterial species. Resistance to tetracycline occurs by different mechanisms regulated by various genes.

2. The study was conducted to determine the tetracycline resistance and prevalence of tetracycline resistance determinants among Escherichia coli strains isolated from broilers in northern Iran.

3. Minimum inhibitory concentration (MIC) of tetracycline and susceptibility pattern of the isolates were screened using micro-dilution and disk diffusion methods, respectively. The presence of 7 tetracycline resistance genes including tetA, tetB, tetC, tetD, tetE, tetG and tetM was tested using the polymerase chain reaction.

4. Among 100 strains isolated from broilers, 73% were identified as tetracycline resistant. All isolates showed the presence of tetracycline-associated genes. The most prevalent genes were tetA (46%) and tetB (41%) and totally, 17 different genotypes were recognised according to the presence of tetracycline resistance genes. Statistical analysis revealed that concomitant presence of the resistance genes significantly increased the tetracycline MIC and effectiveness of phenotypic characterisation.

5. The results demonstrated a high occurrence of tetracycline-resistant E. coli and related genes among broilers which presents a risk of increasing these strains in human infections associated with food animals.  相似文献   

2.
Mandibular pyogranulomatous osteomyelitis was diagnosed in a female Sannen goat. The doe presented for difficulty prehending and chewing food. The left mandible was swollen and firm on palpation. Radiographs revealed changes consistent with osteomyelitis of the affected mandible. Arcanobacterium pyogenes was isolated from aspirates of swollen mandible. Despite antimicrobial therapy, the goat died. Histopathological findings were consistent with pyogranulomatous disease of the affected mandible. The histopathological findings were similar to those reported for actinomycosis, caused by Actinomyces bovis. Mandibular osteomyelitis is a common condition in cattle and very rare in goat.  相似文献   
3.
1. The occurrence of Arcobacter spp. and three pathogenic species of Arcobacter from Iranian poultry carcasses was investigated at different steps of broiler processing to determine critical control points for reducing carcass contamination.

2. Samples were collected from (a) cloaca immediately before processing, (b) different points during processing and (c) at different stations in a processing plant of a slaughterhouse in southern Iran.

3. After enrichment steps in Arcobacter selective broth, DNA of the samples was extracted and three significant pathogen species of Arcobacter were identified based on polymerase chain reaction (PCR) detection of 16S rRNA and specific species PCR.

4. Out of a total of 540 samples, 244 (45%) were positive for Arcobacter spp. Arcobacter butzleri was more frequently detected (73% ± 13.9%) than A. cryaeophilus (9% ± 13.9%) and A. skirrowii (4.1%). In addition, co-colonisation (A. butzleri and A. cryaerophilus) occurred in 13.9% of the positive samples.

5. The results indicate a high prevalence of Arcobacter in the investigated slaughterhouse and broiler carcasses and that Arcobacter is not a normal flora of the broilers. Evidence for the presence of Arcobacter in the environment and water of processing plants suggests that these are sources of contamination of poultry carcasses. In addition, contamination of the poultry carcasses can spread between poultry meats in different parts and processes of the slaughterhouse (pre-scalding to after evisceration).  相似文献   

4.
Journal of Plant Diseases and Protection - The present study aimed to evaluate the effects of Zataria multiflora essential oil at different concentrations (0, 100, 200, 300 and 500 ppm) on the...  相似文献   
5.
Hyperlipidemia in Caspian miniature horses: Effects of undernutrition   总被引:1,自引:0,他引:1  
The susceptibility of Caspian miniature horses to hyperlipidemia was followed in a study of healthy Caspian miniature horses in which food but not water was withheld for 48 hours. Two months before the study, the horses were fed a high-energy diet. The mean of weight gain was 26.46 kg per horse during this period. All horses had a normal rectal temperature, respiratory rate, and pulse throughout the experiment. During the period of food deprivation, levels of serum triglyceride, aspartate aminotransferase, and alanine aminotransferase significantly (P < .05) increased and glucose concentration decreased. As a conclusion, Caspian miniature horses were susceptible to hyperlipidemia, but they did not show classic hyperlipemia syndrome.  相似文献   
6.
The mucoadhesive Chitosan (CS) nanofibers as a drug delivery system were developed. Chitosan was modified via the immobilization of thiol groups from L-cysteine as a mucoadhesive reagent. The mucoadhesive properties of the chitosan nanofibers were evaluated by tensiometer set and via tensile studies. Drug and mucoadhesive agent loading lead to decrease diameters and increased porous of nanofibers. The release of Tetracycline (Tet) and Triamcinolone (Tri) were increased with increasing immersion time and it became constant at long immersion times. Mucoadhesion studies were done at pH 2–7 and in pH 6 maximum mucoadhesive properties observed. Release studies demonstrated a sustained release of both drug continued up to 48 hours. Microbial studies were performed on the nanofibers. The drug delivery system represented a novel tool for improve the therapeutic efficacy of various drugs that are poorly absorbed from the gastrointestinal tract. Also it is an efficient system for treatment of oral ulceration.  相似文献   
7.
8.
This study investigated the effects of fish meal replacement by Spirulina platensis meal on growth, survival, body biochemical composition, and reproductive performance of Trichopodus trichopterus until the first spawning for 16 weeks. The fish fed dietary algal meal at levels of 2.5, 5, 10, and 20 % against those received fish meal only as control. The results showed that indicators such as belly diameter, feed intake, feed conversion ratio (FCR), and viscerosomatic index were significantly different between treatments with 5 and 10 % algal replacements (P < 0.05). The growth factors including final weight, weight gain, total length, fork length, and body height of fish did not show significant differences (P > 0.05) between the treatments. Feed intake increased up to 10 % replacement level and then decreased, though the best FCR values (0.77–0.79) were obtained with 2.5 and 5 % substitutions. The body lipid content showed a statistically marked decrease (P < 0.05) as a result of the algal replacements, but the amounts of protein and moisture were not significantly (P > 0.05) different between treatments. All fish fed S. platensis meal had greater gonadosomatic indices (19.4–21.85 %) than that of the control in spite of insignificant differences (P > 0.05) in their ovary weights (2.07–2.21 g). Absolute fecundity ranged between 7300 and 12,700 eggs/female with the highest amount in fish fed with replaced S. platensis levels of 2.5–10 %. The second-order polynomial regression analysis between absolute fecundity and substitution levels of algal meal was y = ?0.5319x 2 + 106.87x + 7812.9 (R 2 = 0.9642), and the optimal substitution level was determined to be 8.13 % for maximum absolute fecundity. Hatching percentages in the control and 20 % replacement were much lower (P < 0.05) than those in the other treatments (78–86 %). Given the relative enhancement of growth parameters and significant improvement in reproductive performance of broodstock three-spot gourami, 8.1–9.6 % S. platensis meal instead of fish meal is recommended in the diets.  相似文献   
9.
The influence of flower position on the inflorescence on opening day, gender, and petal persistence was studied in three olive cultivars: Manzanillo, Mission, and Frantoio. In each cultivar, 45 inflorescences were checked every morning from flower opening to petal fall. Perfect flowers opened mainly in the beginning of the flower opening period, and staminate flowers opened later. Flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than the flowers located on the secondary branches. Flower position had also a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. Among the primary branches, the branch arising immediately next to the terminal flower had the latest flowers to open and the lowest percent of perfect flowers. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal half of 120 inflorescences, on which the flowers tend to be perfect, in three trees of Manzanillo were removed about 1 month before full bloom. There was a highly significant effect on the percent of perfect flowers that opened on the proximal half. Flower competition may be a reason for pistil abortion in flowers located on secondary branches.  相似文献   
10.
The aim of the present study was to investigate the efficacy of early single‐dose probiotics administered from proximal or distal gastrointestinal tract on quails’ performance and small intestinal morphology. A total of 120 Japanese quail (Coturnix coturnix japonica) 1‐d‐old chicks were divided into the following experimental groups before being transferred to the raising room: (i) control (no probiotic administered); (ii) oral group (received probiotics via oesophageal gavage); and (iii) vent lip group (received probiotics directly into vent). Four replicates of 10 chicks per cage were considered for each treatment and birds were raised up to 35 days in the same conditions with ad libitum access to feed and water. A commercial probiotics (Protexin, Somerset, UK) used in this study contained 2 × 109 cfu/g of nine different micro‐organisms. On day 35, all birds were weighed and then three birds in every pen were killed via cervical dislocation. Two cm of mid‐point of duodenum and ileum were cut for histomorphology assays. Both probiotics‐treated groups had higher body weight and body weight gain than control (< .01). Ileum was longer in probiotics‐treated groups than in the control (< .01). Orally treated birds had the highest duodenum villus height and crypt depth (< .01). In the cloacally treated quails, ileum villus length was higher than the both other groups, and crypts’ depth was deeper than the control (< .01). The numbers of both types of goblet cells (acidic mucin producer and neutral mucin producer) were higher in the birds receiving probiotics than control birds (< .01). Although there were no statistical differences in performance values between the different ways of probiotics entrance into gut, some intestinal histomorphometric parameters were improved in ileum of the birds receiving probiotics through distal gut that is cloaca (< .01).  相似文献   
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