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91.
Cancer represents a set of more than 100 diseases, including malignant tumors from different locations. Strategies inducing differentiation have had limited success in the treatment of established cancers. Marine sponges are a biological reservoir of bioactive molecules, especially lectins. Several animal and plant lectins were purified with antitumor activity, mitogenic, anti-inflammatory and antiviral, but there are few reports in the literature describing the mechanism of action of lectins purified from marine sponges to induce apoptosis in human tumor cells. In this work, a lectin purified from the marine sponge Cinachyrella apion (CaL) was evaluated with respect to its hemolytic, cytotoxic and antiproliferative properties, besides the ability to induce cell death in tumor cells. The antiproliferative activity of CaL was tested against HeLa, PC3 and 3T3 cell lines, with highest growth inhibition for HeLa, reducing cell growth at a dose dependent manner (0.5-10 μg/mL). Hemolytic activity and toxicity against peripheral blood cells were tested using the concentration of IC(50) (10 μg/mL) for both trials and twice the IC(50) for analysis in flow cytometry, indicating that CaL is not toxic to these cells. To assess the mechanism of cell death caused by CaL in HeLa cells, we performed flow cytometry and western blotting. Results showed that lectin probably induces cell death by apoptosis activation by pro-apoptotic protein Bax, promoting mitochondrial membrane permeabilization, cell cycle arrest in S phase and acting as both dependent and/or independent of caspases pathway. These results indicate the potential of CaL in studies of medicine for treating cancer.  相似文献   
92.
The effect of the replacement of corn silage with spineless cactus associated with Tifton 85 hay or sugarcane bagasse was evaluated on the performance, body weight components and sheep meat quality. Twenty-one Santa Inês male sheep with initial body weight of 22.9 ± 2.9 kg were used. They were confined in individual stalls for 74 days receiving the following diets: corn silage + concentrate (CS); spineless cactus + Tifton 85 hay + concentrate (TH); spineless cactus + sugarcane bagasse + concentrate (SB). After the feedlot period, the animals were slaughtered and their body components were weighed and sampled. Data were submitted to Tukey’s test at 5% probability. The average daily gain (0.25 vs 0.14 kg), cold carcass weight (13.3 vs 13.7 kg), loin muscularity (0.6 vs 0.4 kg) and liver weight (0.7 vs. 0.5 kg) were higher (P < 0.05) for the TH diet when compared to that for the CS. The physical-chemical parameters of meat were not influenced (P > 0.05) by the treatments and presented about 20.1% of crude protein, 6.1% of crude fat and shear force of 2.0 kgf/cm2. In complete diets for sheep, Tifton 85 hay associated with spineless cactus provides greater weight gain, cold carcass muscularity and organ weight when compared to those for animals fed with corn silage as exclusive roughage. Sugarcane bagasse associated with spineless cactus may replace corn silage in complete diets for sheep.  相似文献   
93.
We aimed to evaluate the effects of chitosan and microbial inoculant addition to sugarcane silage fermentation, gas and effluent losses, chemical composition, in situ dry matter (DM), neutral detergent fibre (NDF) degradation and aerobic stability. A completely randomized design with four treatments (n = 40) was performed. It was arranged in a 2 × 2 factorial scheme with chitosan [0 and 6 g/kg of sugarcane DM—1.66 g/kg of natural matter (NM)] and microbial inoculant (0 and 8 mg/kg on NM). Each g of inoculant contained 3.9 × 1010 UFC/g of Pediococcus acidilactici and 3.75 × 1010 UFC/g of Propionibacterium acidicipropionici. The addition of microbial inoculant increased lactic acid concentration in silos treated with chitosan. Furthermore, chitosan increased pH and tended to increase acetic acid of silage. In contrast, the inoculant decreased pH and acetic acid, besides increasing ethanol concentration. As chitosan addition increased DM recovery, inoculant addition decreased it. Chitosan decreased NDF and acid detergent fibre (ADF) level and increased DM degradation, while inoculant decreased DM content, DM and NDF degradation. In addition, chitosan improved the aerobic stability only in non‐inoculated silos. Thus, chitosan has a positive effect on silage fermentation, reducing fermentative losses, and improving silage chemical composition and degradation. Conversely, the addition of microbial inoculant negatively affected silage DM recovery, chemical composition, and its association with chitosan decreased the aerobic stability when compared to the exclusive use of chitosan.  相似文献   
94.
The prevalence of antibodies to Neospora caninum was examined in six wild Artiodactyla species, and in five wild Carnivora species from Kenya. Blood sera (104 wild ungulates from Marula Estates (MEs), and 31 wild carnivores from Masai-Mara reserve and from other wildlife areas in northern and Southern Kenya), were screened using a Neospora agglutination test (NAT), with a twofold dilution (1:40-1:320 titres). Presence of NAT antibodies to N. caninun is reported here for the first time in zebra (Equus burchelli), eland (Taurotragus oryx), African buffalo (Syncerus caffer), Thompson gazelle (Gazella thompsoni), impala (Aepyceros melampus), warthog (Phacochoerus aethiopicus), spotted hyena (Crocuta crocuta) and in free-ranging cheetah (Acinonyx jubatus). At 1:80 dilution, prevalence was 61.5% in eland, 58.5% in zebra, 19.2% in Thompson gazelle, 33.3% in warthog, 50% in African buffalo, 30% in lion (Panthera leo), 20% in cheetah, and 33.3% in spotted hyena. Antibodies up to 1:320 titre were detected in eland (38.4%), zebra (19.5%), Thompson gazelle (3.8%) and lion (5%). Amongst herbivores, sero-prevalence was significantly (P<0.05) higher, at all dilutions, in "grazer/digger" species (e.g. eland and zebra) than in non-"grazer/digger" species (e.g. impala and Thompson gazelle). No antibodies to N. caninum were found in two leopards (Panthera pardus) and one serval (Felis serval). Our results indicates a steady presence of N. caninum in wild mammals from Kenya. The hypothesis of a sylvatic cycle of N. caninum could be suggested, but more data are needed to verify the hypothesis, as to evaluate the role of N. caninum infection on the dynamics of wild animals population in the study area.  相似文献   
95.
OBJECTIVE: In view of the considerable importance of venereal transmission of bovine leptospirosis, the objective of the present study was to compare the polymerase chain reaction (PCR), culture/isolation and serology to detect leptospire infection in bovine semen. DESIGN: Blood for serologic examination and semen for bacterial culture and PCR were collected from 20 bulls at artificial insemination centres in Brazil. Each animal was sampled twice for serology. RESULT: Forty-five percent (9/20) of the serum samples collected showed agglutinin titers to serovar hardjo in the first sample and 25% (5/20) had agglutinin titers to serovar hardjo in the second sample. Eighty percent (16/20) of semen samples were positive by PCR. Leptospires could not be isolated from any of the semen samples examined. CONCLUSION: Polymerase chain reaction can be a method of great potential for the detection of leptospires at artificial insemination centres.  相似文献   
96.
Does literacy improve brain function? Does it also entail losses? Using functional magnetic resonance imaging, we measured brain responses to spoken and written language, visual faces, houses, tools, and checkers in adults of variable literacy (10 were illiterate, 22 became literate as adults, and 31 were literate in childhood). As literacy enhanced the left fusiform activation evoked by writing, it induced a small competition with faces at this location, but also broadly enhanced visual responses in fusiform and occipital cortex, extending to area V1. Literacy also enhanced phonological activation to speech in the planum temporale and afforded a top-down activation of orthography from spoken inputs. Most changes occurred even when literacy was acquired in adulthood, emphasizing that both childhood and adult education can profoundly refine cortical organization.  相似文献   
97.
98.
Few studies have attempted to understand how fish growth scales at community and macroecological levels. This study evaluated the drivers of reef fish growth across a large gradient of environmental variables and a range of morphological and behavioural traits. We compiled Von Bertalanffy Growth parameters for reef fishes and standardized K relative to species maximum sizes, obtaining Kmax. We then modelled the response of Kmax to body size, diet, body shape, position relative to the reef, schooling behaviour, sea surface temperature, pelagic net primary productivity and ageing method, while accounting for phylogenetic structure in the data. The final model explained 61.5% of the variation in Kmax and contained size, temperature, diet, method and position. Body size explained 64% of the modelled Kmax variability, while the other variables explained between 6% (temperature) and 2.5% (position). Kmax steadily decreased with body size and increased with temperature. All else being equal, herbivores/macroalgivores and pelagic reef fishes had higher growth rates than the other groups. Moreover, length–frequency ageing tended to overestimate Kmax compared to other methods (e.g. otolith's rings). Our results are consistent with (a) metabolic theory that predicts body size and temperature dependence of physiological rates; and (b) ecological theory that implies influence of resource availability and acquisition on growth. At last, we use machine learning to accurately predict growth coefficients for combinations of traits and environmental settings. Our study helps to bridge the gap between individual and community growth patterns, providing insights into the role of fish growth in the ecosystem process of biomass accumulation.  相似文献   
99.
We aimed to study the normal puerperium in the bitch. Ovariohysterectomy was performed in nine bitches, each at a different day after normal whelping; their genital tract was subject to gross anatomical examination, as well as to histological examination and electron microscopy scanning. Corpora albicans were evenly distributed in the left and right ovaries and placental sites were evenly distributed among left and right uterine horns. Placental sites were initially of dark green to grey colour, later becoming dark brown; their length and height progressively decreased. Height of the myometrium and diameter of the uterine glands progressively decreased. Trophoblast-like cells were consistently observed at the placental sites and on the surface of the interplacental areas, at all time points where hysterectomy had been performed. It is suggested that involution of the canine genital tract can last up to 3 months and is slow. Continuous (up to D84 post-partum) presence of prominent placental sites should be considered a normal feature of canine uterine post-partum involution.  相似文献   
100.
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