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81.
RAPD and SSR markers were used for genetic diversity evaluations among 15 genotypes selected from the genus Prunus L. Altogether 40 RAPD primers and 21 primer pairs designated for microsatellite loci were applied on the whole group of genotypes.  相似文献   
82.
Within a three-year period, 178 clinically healthy and 442 sick cats (patients of the Clinic for Small Animal Diseases of the University of Veterinary Medicine, Brno) were examined for the presence of antibodies to Toxoplasma gondii. Antibodies to T. gondii were detected in 34.8% of the animals without clinical signs of the disease and in 54.3% of the sick cats (P less than 0.01). Compared with the group of clinically healthy cats, the specific antibodies occurred significantly more frequently in the cats suffering from diseases of the digestive tract (P less than 0.01), particularly in those with acute gastroenteritis, and in those having liver disorders (P less than 0.01; P less than 0.05). A statistically significantly higher occurrence of antibodies to T. gondii was also recorded in the cats with disorders of the nervous system (P less than 0.05; P less than 0.01), particularly in those with symptoms of extraordinary aggressivity at the age span from four months to three years. Enlarged lymph nodes were found out in 44% of the cats having antibodies to T. gondii. This is 15% more than the average for the investigated set of animals, which is a statistically significant dependence (P less than 0.01).  相似文献   
83.
A serological examination by the microagglutination reaction of lysis (RMAL) was performed with 12 leptospira strains to investigate 1272 blood serums of dogs coming for various kinds of treatment to the outpatient ward of the veterinary hospital. The higher infestation rate was recorded in the dogs from outside the city (14.08%) than in the city dogs (7.96%). A considerably high infestation was found in the dogs of the service breeds (13.47%). The males were infested more frequently (10.99%) than the bitches (7.22%). As for age, young dogs until the age of one year were found to be infested more frequently. Separate significant titres were demonstrated with the leptospira of the Grippotyphosa, Icterohaemorrhagiae, Sejroe, and Australis (L. bratislava) serological groups. Reactions with the leptospira of other groups were recorded only at low titres: they were as coagglutinations with parallel high-titre reactions with the leptospira of the Grippotyphosa and Icterohaemorrhagiae groups.  相似文献   
84.
The effect of cold milk drink on selected biochemical and haematological parameters in calves blood during the milk nutrition period was observed in farm conditions, as compared with the current feeding regime. The test group was offered cold sour milk drink (one 1 MKS Laktosan acidulated with addition of 22 ml formic acid to a pH of 4.6) at the temperature of 16 degrees C after four-day-adaption till the calves average age of 61 days. The control group was given MKS Laktosan in the usual way, using the same amount of the drink and time of serving it. During the test the performance was recorded, as well as haemoglobine content, total protein, haematocrit, urea, glucose, cholesterol, transaminase (ALT and AST) activities and alkaline blood reserves. In the studied parameters no significant differences were found between the test and control group (P greater than 0.05). The average daily gains of live weight during the period of milk nutrition was 0.762 kg in the test group and 0.667 kg in the control group.  相似文献   
85.
ABSTRACT: BACKGROUND: We have developed a new analytical approach for isolation and quantification of cytokinins (CK) in minute amounts of fresh plant material, which combines a simple one-step purification with ultra-high pressure liquid chromatography-fast scanning tandem mass spectrometry. RESULTS: Plant tissue samples (1-5 mg FW) were purified by stop-and-go-microextraction (StageTip purification), which previously has only been applied for clean-up and pre-concentration of peptides. We found that a combination of two reverse phases and one cation-exchange phase, was the best tool, giving a total extraction recovery higher than 80%. The process was completed by a single chromatographic analysis of a wide range of naturally occurring cytokinins (bases, ribosides, O- and N-glucosides, and nucleotides) in 24.5 minutes using an analytical column packed with sub-2-microne particles. In multiple reaction monitoring mode, the detection limits ranged from 0.05 to 5 fmol and the linear ranges for most cytokinins were at least five orders of magnitude. The StageTip purification was validated and optimized using samples of Arabidopsis thaliana seedlings, roots and shoots where eighteen cytokinins were successfully determined. CONCLUSIONS: The combination of microextraction with one-step high-throughput purification provides fast, effective and cheap sample preparation prior to qualitative and quantitative measurements. Our procedure can be used after modification also for other phytohormones, depending on selectivity, affinity and capacity of the selected sorbents.  相似文献   
86.
Impairment of the peripheral lymphoid compartment in iron-deficient piglets   总被引:2,自引:0,他引:2  
The aim of this study was to investigate the effect of neonatal iron deficiency on immune functions in young piglets. While control piglets were not given any iron preparation until the age of 21 days, another group of piglets was given 200 mg of Fe(3+)-dextran i.m. on day 3. Red blood cell parameters in the former, iron-deficient group were characteristic of hypochromic anaemia. In addition, the total leucocyte count (P < 0.01), relative and absolute neutrophil count (P < 0.01) and absolute lymphocyte count (P < 0.05) in peripheral blood were found significantly lower in iron-deficient piglets than in their iron-supplemented counterparts. Lymphocyte activity as measured by in vitro lymphocyte transformation test was impaired in iron-deficient piglets. A statistically significant decrease in circulating B-lymphocyte numbers was found in non-supplemented animals. Iron deficiency apparently negatively influenced the immunocompetence in piglets.  相似文献   
87.
In the course of two years, 663 dogs from Brno and its vicinity were subjected to clinical and parasitological examination with a special reference to the occurrence of coccidia. A saturated sugar solution with the specific weight of 1150 was used as the flotation medium. Coccidia were found in 2.17% of the dogs examined. The oocysts of the groups Isospora ohioensis, I. burowsi and I. neorivolta were identified most frequently (2.11% of the dogs). Four dogs (0.60%), all alike, eliminated the oocysts of Hammondia heydorni and sporocysts of Sarcocystis species, and two dogs oocysts of Hammondia heydorni and sporocysts of Sarcocystis species, and two dogs (0.30%) excreted oocysts of I. canis. Out of the animals infected, 58% were younger than six months. Clinical signs were observed only at a medium to strong invasion with oocysts of the species I. ohioensis, I. burowsi and I. neorivolta. The digestive tract was affected most severely--the animals suffered from bloodless diarrhoeas lasting two to twelve days, from occasional vomiting and systemic dehydration. Invasion by I. canis, Hammondia heydorni and Sarcoystis sp. did not cause any clinical changes.  相似文献   
88.
The aim of the study was to assess the role of pest control as a preventive measure in the control of trichinosis. The investigation was designed as a retrospective cohort study in the Virovitica-Podravina County. The incidence of trichinosis was determined according to the presence or absence of exposure to protective pest control measures. Differences in the rate of trichinosis infection were determined by calculating relative risk (RR), i.e., the ratio of absolute risk in the two groups. In this epidemiological study, data collected in the County area regularly covered by pest control (exposure area) were compared with other areas not covered by regular pest control measures (non-exposure area). The study included 132 subjects living in the County and locally infected with trichinosis. Patient data were obtained from their medical history, epidemiological survey and epidemiological questionnaire on the source (autochthony) of the disease. The study also included 133,028 domestic pigs, 875 wild animals (mostly wild boar) and 111 trapped rats. All samples were examined by the method of trichinoscopy at authorized veterinary institutions of the County. Trichinosis infection was recorded in 1012 of 79,534 domestic pigs in the area exposed to pest control measures and in 51 of 53,494 domestic pigs from the rest of the County. RR for the exposure area vs. non-exposure area was 13.35 (95% CI 10.08-17.68; p<0.05); according to particular areas, RR was 3.66 (95% CI 2.62-5.13) for Pitomaca, 22.47 (95% CI 13.27-38.08) for Slatina and 118.89 (95% CI 29.7-476.01) for Orahovica (p<0.05 all). Domestic pigs from the County areas exposed to regular pest control measures had a 13-fold likelihood of infection recorded in pigs from County areas where pest control measures were not or were only occasionally performed. Quite unexpectedly, these results revealed a failure of pest control to reduce the incidence of trichinosis. The spread of trichinosis obviously occurs by some routes obviating the impact of pest control.  相似文献   
89.
Soils and housedusts were collected from three areas of Pribram,an historic metal mining and smelting town in the Czech Republic. The main objectives of the study were: (i) to assessthe influence of physico-chemical form, particle size, soilproperties and contaminant source on Pb bioavailability andexposure risk; (ii) compare the Pb bioavailability data obtainedfrom the mining and smelting areas and assess whether anydifferences observed could be attributed to the factors thoughtto exert an influence. Lead concentrations were highest in thesmelter area. Mining area garden soils also contained elevatedPb concentrations. Solubility of housedust Pb in 0.12 M HCl (asurrogate for stomach acid) was similar in all study areas andwas similar to values reported in the literature. However, 0.12M HCl solubility of garden soil Pb was low in the mining areacompared to the other study areas and compared to other urbanareas. Blood Pb concentrations were also relatively low in themining area compared to the other study areas and the reducedsoil Pb solubility observed in this area was suspected as aninfluencing factor. However, exposure pathways may also beimportant in explaining the differences observed.  相似文献   
90.
Montane Norway spruce forests of Central Europe have a very long tradition of use for timber production; however, recently there has been increasing concern for their role in maintaining biological diversity. This concern, coupled with recent severe windstorms that led to wide-spread bark beetle outbreaks, has brought the management of montane spruce forests to the forefront of public policy discussions in Central Europe. In order to shed light on the natural development and current structure of mature montane spruce forests, we established four 0.25 ha research plots in a semi-natural montane spruce forest in the Šumava Mountains (The Bohemian Forest), Czech Republic. We mapped all trees, extracted increment cores for age and growth-pattern analyses, and inventoried all current tree regeneration, including the substrates on which it was found. Stands were characterized by uni-modal tree diameter distributions and high basal areas (56.6 m2 ha−1 on average), indicating a natural transition from the stem exclusion phase towards the understory reinitiation phase. The stands showed largely single-cohort recruitment age structures, however, with recruitment spanning seven decades. Our analyses suggest that this cohort existed as advance regeneration prior to major disturbances in the late 1800s, which included post-bark beetle salvage logging. Spatial pattern analyses of living and dead stems combined, showed an increase in uniformity of living trees, pointing to the role of natural density-dependent mortality. However, past growth patterns and historical documentation suggest that low intensity canopy disturbances (wind and snow) also caused mortality and diversified canopy structure. Because the stands developed naturally over the past 120+ years and thus escaped thinning operations, high volumes of coarse woody debris (94 m3 ha−1) and snag densities (546 stems ha−1) have accrued. Advance spruce regeneration was quite abundant and existed primarily on deadwood substrates, even though these occupied only a small percent of stand area. Because of salvage logging in the late 1880s, these stands do not qualify, according to the traditional paradigm, as natural spruce forests. As a result, they are recently subject to active management practices including salvage logging that remove dead and dying trees. Given the importance of deadwood for forest regeneration and recovery from disturbance, as demonstrated in this study, we argue that dead wood removal may limit future natural regeneration in these stands. Thus, the purported benefits of removing dead and dying trees from semi-natural forests must be carefully weighed against the potential detrimental impacts on natural spruce forest regeneration and biodiversity.  相似文献   
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