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171.
This work was carried out to investigate the pulp composition of four mango cultivars (Haden, Tommy Atkins and Ubá) at the ripening stage in relation to three components with antioxidant potential (total phenolics, carotenoids and ascorbic acid). Total phenolic compound content was estimated by the Folin-Ciocalteu reagent and total carotenoid content by spectrophotometry at 450 nm. The contents of β-carotene and total vitamin C (ascorbic acid and dehydroascorbic acid) were quantified by high performance liquid chromatography. Differences were found among the four mango cultivars in all the components analyzed. The content of phenolic compounds ranged from 48.40 (Haden) to 208.70 mg/100 g (Ubá); total carotenoid from 1.91 (Haden) to 2.63 mg/100 g (Palmer); β-carotene from 661.27 (Palmer) to 2,220 μg/100 g (Ubá) and total ascorbic acid ranged from 9.79 (Tommy Atkins) to 77.71 mg/100 g (Ubá). These results corroborated previous information that mangoes are a good source of antioxidants in human diet.  相似文献   
172.
The increasing incidence of candidiasis has drawn the attention of scientists and clinicians attempting to improve methods of studying Candida yeasts. PCR amplification followed by agarose gel electrophoresis (PCR-AGE) and the manual method (morphological characteristics, biochemical profiles and culturing on CHROMagar-Candida) and VITEK 2 automated method were used to test a total of 30 fungal strains from dog sources. The strains were obtained from cases of dermatitis, otitis externa and from the ears, oral mucosa, vaginal mucosa, prepuce and perianal region of clinically normal dogs. After identification as Candida yeasts by the manual method, the strains were analyzed using both VITEK and PCR-AGE methods. Isolates of C. parapsilosis ATCC 22019, C. krusei ATCC 6258 and C. albicans ATCC 10231 were included as controls. The universal primers ITS1, ITS3 and ITS4 were used in two independent PCR reactions. Of 30 yeast isolates, 3 isolates (Saccharomyces cerevisiae, C. rugosa and C. parapsilosis) that were incompletely identified by the manual method were identified with the PCR-AGE and VITEK methods. The results revealed a 96.7% and 86.7% concurrent identification between the PCR-AGE and VITEK methods versus the manual method, respectively. PCR-AGE showed a greater level of concordance with the manual method, besides being faster and more sensitive than the other methods examined, and is therefore indicated for routine diagnostic testing of Candida spp. strains from veterinary sources.  相似文献   
173.
The effects of successive brassinosteroid analogue (BR) applications (0.1 mg l−1 of brassinosteroid analogue BB-16) were evaluated on commercial yellow passion fruit (Passiflora edulis f. flavicarpa) orchards in the first year of production. The treatments applied were: control, BR-1 (1 BR application shortly after the first flowers appeared), BR-2, BR-3, BR-4 and BR-5 (BR application in two, three, four and five consecutive weeks after the appearance of the first flowers, respectively). The fruits were collected for seven consecutive weeks (105 fruits treatment−1) and fruit mass, length and diameter, soluble solid contents; pulp mass and peel thickness were evaluated in the laboratory. Multivariate analysis was performed in order to determine whether there were differences among the treatments taking into account all the measurements made. BR-3 was the most promising treatment because it produced the highest number of fruits plant−1 (81.5) compared to the control (53.5) and the soluble solid content was 1 °Brix greater than the control. The BR-3 treatment resulted in a 65% increase in the estimated yield of the passion fruit plants, corresponding to 20 t ha−1 compared to the control yield of 12 t ha−1. The results showed that BB-16 sprayed during a period of reproductive development can increase the number of fruits per plant.  相似文献   
174.
The effect of Haemonchus contortus infection in sheep fed with a moderate and high protein content diet was evaluated in two breeds of sheep. Forty-eight Ile de France and Santa Ines lambs were maintained indoors since birth, in worm-free conditions. The lambs were allocated after weaning in four groups of six animals per breed, which were either infected or remain uninfected and given access to either a moderately or highly metabolizable protein diet. The moderately and highly metabolizable protein diets were calculated to supply 75 and 129 g metabolizable protein per kg of dry matter (MP/kg DM), respectively. The infection consisted of a trickle infection with 300 infective larvae, three times a week, for 12 weeks. Significant differences were observed for mast cell, globule leukocyte and eosinophil counts in the abomasal mucosa of the infected groups compared to the control of both breeds (P<0.05), regardless of the diet supplied. Significantly higher IgA anti-L5 antibody was detected in the infected Santa Ines groups than in the infected Ile de France groups (P<0.05). Increased metabolizable protein supply resulted in larger body weight gain and higher packed cell volumes for both breeds (P<0.05). Both breeds showed an increased ability to withstand the pathophysiological effects of H. contortus infection when given access to the highly metabolizable protein diet. However, increased metabolizable protein supply resulted in reduced worm burdens in Santa Ines lambs but not in the Ile de France lambs (P<0.05). The present results show that the increase in protein content in growing lamb diets may benefit resistance and resilience to gastrointestinal parasites but that these benefits may vary among breeds.  相似文献   
175.
The dynamics of plasma cortisol, blood glucose, plasma chloride and liver glycogen were investigated in matrinxã (Brycon cephalus) submitted to capture and various periods of crowding. A total of 400 fish (700±22 g weight) were distributed in four ponds divided into four 50‐m2 squares (25 fish/square, 350 g L?1), where they were acclimated for 30 days. On the sampling day, after 24 h without food, all fish from three squares were transferred to the fourth square. Six fish were sampled before the procedure (control group, zero time) and 1, 3, 6 and 24 h after the capture and crowding. Each sampling was performed in a different pond to prevent additional stress. Fish were anaesthetized and blood and liver collected for biochemical analysis. Water temperature, pH, dissolved oxygen, alkalinity, ammonia and nitrite levels were within acceptable levels for matrinxã rearing. Slight but not significant increases were verified in plasma cortisol and blood glucose levels, as were decreases in plasma chloride and liver glycogen levels. The results suggest that matrinxã is highly tolerant to the procedures of capture and short‐term crowding.  相似文献   
176.
Parasites resembling Neospora caninum or Toxoplasma gondii were detected by cytologic examination of cerebrospinal fluid (CSF) from a dog with neurologic disease. The dog became severely ill and was euthanized. Canine tissue homogenates were used for direct parasite isolation in cell culture, bioassay in 2 mouse lineages, and PCR. T. gondii was isolated in monkey kidney cells, and species identity was confirmed by PCR. Inoculated parasites were highly virulent for mice, which developed clinical signs and were euthanized immediately. PCR-RFLP for T. gondii using the cultured isolate (TgDgBA22) was conducted with 12 genetic markers, and a unique recombinant strain was identified. Detection of T. gondii by CSF cytology, although described in humans, had not been reported previously in dogs, to our knowledge, and was crucial for the diagnosis of toxoplasmosis in the examined dog.  相似文献   
177.
In a dairy herd experiencing an abortion outbreak, 49% of the 119 cows were positive for Neospora caninum antibodies and the remaining 51% were seronegative. Using immunohistochemical analysis of foetal brain tissue, Neospora cysts and bradyzoite clusters were identified in two of the 15 aborted foetuses submitted for testing. Other agents that commonly cause abortions were not found. These results, coupled with neurological clinical symptoms in new-born calves, implicated N. caninum as the major cause of abortions in this dairy herd. This is the first report that associates N. caninum infection with bovine abortions in Portugal.  相似文献   
178.
The first results of a study relative to the demography of wild Lima bean (Phaseolus lunatus L.) populations in the Central Valley of Costa Rica are presented. Six wild populations were selected in the four mainly representative ecological zones of this region and several 1 m2 quadrats were demarcated in order to determine the vital rates (fecundity, survival, growth and mortality) of the individuals within each population. These data were collected during two years from 3000 labelled individuals and combined with those relative to the soil seed bank and the seed dormancy to propose a demographic model for a hypothetical mean wild population based on the projection matrix theory. This model helps to determine the growth rate of the population, the stability of its structure and, by using a sensitivity analysis, reveals also the factors most constraining for the population survival. Population behaviour under natural conditions and human pressure are simulated, which allow to propose management practices for in situ conservation.  相似文献   
179.
180.
A diagnosis of congenital stricture of the vestibulo-vaginal fold was reached in an 11-year-old mare without previous reproductive records, during a breeding soundness examination. The mare had an annular stricture of the vestibule–vaginal fold that did not allow palpation or vaginoscopic visual examination of the anterior portion of the vagina. Endoscopic evaluation of both anterior and posterior portions of the vagina revealed a normal mucosa without scar tissue. Ultrasound examination of the cervix, uterus and ovaries did not reveal any other abnormality. The mare had a normal karyotype – 64 XX. Vestibulo-vaginal stricture or stenosis is a congenital anomaly that occurs when there is an incomplete perforation of the hymen or occurs in association with hypoplasia of the genital canal that results in the formation of an annular fibrotic stenosis at the vestibule–vaginal junction. To our knowledge, this is the first report of vestibulo-vaginal stricture in a mare with confirmed normal karyotype, 64,XX.  相似文献   
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