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101.
Pulsed-wave Doppler tissue imaging (pw-DTI) techniques allow the non-invasive assessment of myocardial dynamics. pw-DTI has demonstrated regional and global diastolic impairment in various forms of human and feline cardiomyopathy. We hypothesise that in geriatric cats with systemic diseases that have been linked to specific cardiomyopathies in human beings, the myocardial velocity profile will be altered when compared to either normal or hypertrophic cardiomyopathy (HCM) cats; and that both age and heart rate have a significant affect upon pw-DTI velocities. The aims of this study were to determine whether the feline M-mode or myocardial velocity profile is altered in geriatric cats with disease states that have been linked to specific cardiomyopathies in humans when compared to normal geriatric cats or geriatric cats with HCM and to determine whether age or heart rate has a significant effect upon pw-DTI velocities within these groups of cats. Sixty-six cats aged 8 years or above were included in the study, and were divided as follows: Unaffected (n=8), basilar septal bulge (BSB) (17), HCM (14), hyperthyroid (HiT(4)) (12) and chronic renal failure (CRF) (15). Systolic blood pressure was normal in all the cats. pw-DTI systolic (S'), early (E') and late diastolic (A') velocities were assessed from standardised sites within the myocardium, and the relationships between these and disease group, age and heart rate were then assessed. In cats with HCM, the E' velocity was decreased at various sites. Conversely, the HiT(4) cats demonstrated increased S' velocities. The only site at which the age of the cat was significantly related to myocardial velocities was the S' velocity from the apical mid-septum. There were also significant positive relationships between heart rate and the magnitude of myocardial S', E' and A' velocities of radial motion and S' and A' velocities of longitudinal motion. pw-DTI detected diastolic dysfunction in untreated cats with HCM and increased systolic function in HiT(4) cats. The age of the cat was of little significance, whereas heart rate significantly influenced myocardial velocity profiles.  相似文献   
102.
Faecal samples from 74 cats with chronic large bowel diarrhoea that were living in a rescue colony in Italy, were submitted for assessment of Tritrichomonas foetus by direct microscopy of faecal smears (n=20) and T foetus-specific culture (n=74), with confirmation by polymerase chain reaction (n=1). Twenty-four of the cats (32%) were found to be infected with T foetus. The infected cats were predominantly over a year of age (67%) and were all neutered non-pedigree domestic cats.  相似文献   
103.
Recently, it has been found that the thermal experience during the earliest phases of development could determine the larval and postlarval growth characteristics of teleosts. In order to investigate the effects of the early temperature regime on the advanced stages of growth of sea bass, Dicentrarchus labrax L., this species was reared during the vitelline phase at two temperatures: natural temperature (15 °C) and 17.7±0.1 °C, and then larvae transferred to common temperature (natural temperature). Muscle growth was studied by morphometric and histochemical techniques (mATPase and NADH-TR). Body length and body mass were also measured. During the vitelline phase, muscle growth was similar in both experimental groups, but at 25 days, both hypertrophy and hyperplasia of white muscle fibres were greater in the prewarmed group (p<0.05). At the end of metamorphosis (80 days) and at 120 days, the average diameter of white muscle fibres, as well as the body length, were greater in the prewarmed group (p<0.05), but the number of white fibres did not differ significantly between groups. The morphological mosaic of white muscle fibres was observed at the end of metamorphosis, and the histochemical mosaic appeared gradually since the early postlarval stages. Thus, at 120 days, some specimens in both experimental groups showed three or four different mATPase staining white fibres: low (L), moderate (M), high (H) and/or very high (vH), whereas in other specimens, only L or M mATPase activity fibres were observed. Early T influenced the histochemical maturity of the white muscle. By 120 days, the proportion of H and vH fibres was greater in the prewarmed group (p=0.027; p=0.051, respectively). By 154 days, the four mATPase staining profiles (L, M, H, vH) were observed in all specimens of both groups, but the proportion of vH fibres was still higher in the prewarmed group. By 188 days, 3774 °C-day for the prewarmed group and 3759 °C-day for the natural temperature group, only slight differences between groups were observed in the histochemical properties and no differences were found in the number and size of white muscle fibres, neither in the body length and body mass of specimens.

In conclusion, a slight increase of temperature during the vitelline phase of sea bass increased the muscle growth and body length of fish in subsequent larval and postlarval stages, and advanced the histochemical maturity of the white muscle.  相似文献   

104.
Most investigations related to the characterisation of the enteric nervous system (ENS) are pivoted on the intestine of small rodents, but few studies are available on the ENS of wild or ‘unconventional’ rodents. Anti‐PGP 9.5 and anti‐Hu antibodies were utilised to recognise the distribution pattern of neuronal cell bodies and fibres of the ileum of the Persian squirrel (Sciurus anomalus) ENS. The percentages of subclasses of enteric neurones in the total neuronal population were investigated by neuronal nitric oxide synthase (nNOS), choline acetyltransferase (ChAT), calcitonin gene‐related peptide (CGRP), substance P (SP), and calbindin (CALB). Myenteric plexus (MP) and submucosal plexus (SMP) neurones showing nNOS immunoreactivity (IR) were 41 ± 4% and 11 ± 6%, respectively, whereas cells expressing ChAT‐IR were 56 ± 9% and 74 ± 16%, respectively. nNOS‐IR was co‐expressed by 21 ± 2% and 9 ± 4% of the MP and SMP cholinergic neurones, respectively, whereas the nNOS‐IR MP and SMP neurones co‐expressing ChAT‐IR were 86 ± 6% and 89 ± 2%, respectively. CGRP‐IR and SP‐IR were expressed, respectively, by 13 ± 5% and 6 ± 3% of MP and 18 ± 2% and 2 ± 2% of SMP neurones. CALB‐IR was expressed by 22 ± 8% and 56 ± 14% of MP and SMP neurones, respectively. MP and SMP cholinergic neurones co‐expressed nNOS‐IR (21 ± 2% and 9 ± 4%, respectively) and a very high percentage of nNOS‐IR neurones showed ChAT‐IR (86 ± 6% and 89 ± 2%, respectively). MP and SMP CALB‐IR neurones co‐expressed ChAT‐IR (100% and 63 ± 11%, respectively) and CGRP‐IR (89 ± 5% and 26 ± 7%, respectively). Our data might contribute to the neuroanatomical knowledge of the gastrointestinal tract in exotic mammals and provide a comparison with the available data on other mammals.  相似文献   
105.
Vegetables play an important role in human nutrition and health. Cultivation of vegetable crops is an integral part of the agricultural economy of many developing countries. Vegetable crop productivity and quality are seriously affected by several biotic and abiotic stresses, which destabilize rural economies in many countries. Moreover, absence of proper post-harvest storage and processing facilities leads to qualitative and quantitative losses. In the past four decades, conventional breeding has contributed significantly for the improvement of vegetable yields, quality, post-harvest life, and resistance to biotic and abiotic stresses. However, there are many constraints in conventional breeding, which can only be overcome by advancements made in modern biology. In the last decade various traits such as biotic stress resistance, quality and storage life have been successfully engineered into vegetable crops and some of them have been commercialized. In recent years significant progress has been made to manipulate vegetable crops for abiotic stress tolerance, quality improvement and pharmaceutical and industrial applications. Although the progress in commercialization of transgenic vegetable crops has been relatively slow, transgenic vegetables engineered for nutraceutical and pharmaceutical use will contribute significantly to the value added agriculture in near future.  相似文献   
106.
Muscle histochemical characteristics are decisive determinants of meat quality. The relative percentage and diameters of the different muscular fiber types influence crucial aspects of meat such as color, tenderness, and ultimate pH. Despite its relevance, however, the information on muscle fiber genetic architecture is scant, because histochemical muscle characterization is a laborious task. Here we report a complete QTL scan of muscle fiber traits in 160 animals from a F(2) cross between Iberian and Landrace pigs using 139 markers. We identified 20 genome regions distributed along 15 porcine chromosomes (SSC1, 2, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and X) with direct and(or) epistatic effects. Epistasis was frequent and some interactions were highly significant. Chromosomes 10 and 11 seemed to behave as hubs; they harbored 2 individual QTL, but also 6 epistatic regions. Numerous individual QTL effects had cryptic alleles, with opposite effects to phenotypic pure breed differences. Many of the QTL identified here coincided with previous reports for these traits in the literature, and there was overlapping with potential candidate genes and previously reported meat quality QTL.  相似文献   
107.
The histochemical profiles - mATPase and NADH-TR reactions - of the red and white muscle fibres of gilthead sea bream and sea bass were determined from the first week after hatching. Modifications of the mATPase technique by combinations of pH/time/molarity were carried out in order to compare the sensitivity of the myosin ATPase of each muscle fibre type of the lateral muscle. Results showed that the staining of muscle fibres was independent of small modifications in the technique. The intermediate ‘pink’ muscle was histochemically defined towards the end of the larval life and is considered to be implicated in the growth of the myotome. A layer of external cells was observed, by electron microscopical examination, between the connective tissue of the skin and the superficial red muscle fibres of larvae and postlarvae. It is suggested that the external cells are unlikely to be a source of red muscle fibres and implicated on the growth of the myotome, but rather a part of the dermatome. The timing, areas and mechanisms of hyperplastic growth of the myotome were defined and discussed.  相似文献   
108.
Hypocobalaminaemia in cats has previously been identified, but the incidence reported has varied, and the frequency of folate deficiency is unknown. The aims of this study were to evaluate the incidence of low cobalamin and folate levels in a population of cats that were suffering predominantly from diseases of the alimentary tract (including the liver and pancreas) and to ascertain whether severity of disease (as assessed by bodyweight and body condition score (BCS)) related to degree of deficiency. The study population comprised 103 cats, of which 16.5% had low cobalamin levels and 38.8% had low folate levels. A serendipitous finding was inorganic phosphate levels below the reference range in 48% of the cases. Significant associations were found between subnormal cobalamin levels and median BCS (P=0.049); combined low folate and low cobalamin and bodyweight (P=0.002), BCS (P=0.024) and inorganic phosphate levels (P=0.003). The finding of low levels of folate and cobalamin in clinical cases suggests that supplementation may be indicated more frequently than is currently recognised.  相似文献   
109.
Background: Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance. One of the most studied groups are polyphenolic compounds, given their advantages over other types of additives and their easy potentiation of effects when complexes are formed with metal ions. Therefore, the objective of the present study was to evaluate the impact of dietary supplementation of copper acetate(CA), curcumin(CR), and their combination(CA-CR)against Salmonella Typhimurium colonization, intestinal permeability, and cecal microbiota composition in broiler chickens through a laboratory Salmonella infection model. S. Typhimurium recovery was determined on day 10 post-challenge by isolating Salmonella in homogenates of the right cecal tonsil(12 chickens per group) on Xylose Lysine Tergitol-4(XLT-4) with novobiocin and nalidixic acid. Intestinal integrity was indirectly determined by the fluorometric measurement of fluorescein isothiocyanate dextran(FITC-d) in serum samples from blood obtained on d 10 post-S. Typhimurium challenge. Finally, microbiota analysis was performed using the content of the left caecal tonsil of 5 chickens per group by sequencing V4 region of 16 S rRNA gene.Results: The results showed that in two independent studies, all experimental treatments were able to significantly reduce the S. Typhimurium colonization in cecal tonsils(CT, P 0.0001) compared to the positive control(PC)group. However, only CA-CR was the most effective treatment in reducing S. Typhimurium counts in both independent studies. Furthermore, the serum fluorescein isothiocyanate dextran(FITC-d) concentration in chickens treated with CR was significantly lower when compared to PC(P = 0.0084), which is related to a decrease in intestinal permeability and therefore intestinal integrity. The effect of dietary treatments in reducing Salmonella was further supported by the analysis of 16 S rRNA gene sequences using Linear discriminant analysis effect size(LEfSe)since Salmonella was significantly enriched in PC group(LDA score 2.0 and P 0.05) compared to other groups. In addition, Coprobacillus, Eubacterium, and Clostridium were significantly higher in the PC group compared to other treatment groups. On the contrary, Fecalibacterium and Enterococcus in CR, unknown genus of Erysipelotrichaceae at CA-CR, and unknown genus of Lachnospiraceae at CA were significantly more abundant respectively.Conclusions: CR treatment was the most effective treatment to reduce S. Typhimurium intestinal colonization and maintain better intestinal homeostasis which might be achieved through modulation of cecal microbiota.  相似文献   
110.
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