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71.
Human UBIAD1 localizes to mitochondria and converts vitamin K(1) to vitamin K(2). Vitamin K(2) is best known as a cofactor in blood coagulation, but in bacteria it is a membrane-bound electron carrier. Whether vitamin K(2) exerts a similar carrier function in eukaryotic cells is unknown. We identified Drosophila UBIAD1/Heix as a modifier of pink1, a gene mutated in Parkinson's disease that affects mitochondrial function. We found that vitamin K(2) was necessary and sufficient to transfer electrons in Drosophila mitochondria. Heix mutants showed severe mitochondrial defects that were rescued by vitamin K(2), and, similar to ubiquinone, vitamin K(2) transferred electrons in Drosophila mitochondria, resulting in more efficient adenosine triphosphate (ATP) production. Thus, mitochondrial dysfunction was rescued by vitamin K(2) that serves as a mitochondrial electron carrier, helping to maintain normal ATP production.  相似文献   
72.
Gentamicin (GT) was administered IM to 6 healthy mature mare ponies at a dosage of 5 mg/kg of body weight every 8 hours for 7 consecutive days (total, 21 doses). Two venous blood samples were collected before (trough) and at 1 hour (peak) after the 5th, 10th, 14th, and 19th doses. An endometrial biopsy was done of each mare on days 4 and 7. On the 7th day, just before the 21st administration of GT, base-line blood samples were collected, and 22 blood samples were collected over a period of 48 hours after GT was given. The mares were catheterized on the 7th day, and urine was collected for 24 hours. Serum, urine, and endometrial GT concentrations were determined by a radioimmunoassay technique (sensitivity of 0.3 micrograms/ml of serum). Serum GT concentration data obtained from the terminal phase were best fitted by a 1-compartment open model with a biological half-life of 2.13 +/- 0.43 hours. Total body clearance and renal clearance were 1.69 +/- 0.41 and 1.40 +/- 0.26 ml/min/kg, respectively. Mean endometrial concentrations on day 4 and day 7 were 5.02 +/- 3.3 and 12.75 +/- 1.6 micrograms/g. To achieve mean serum GT concentrations (micrograms/ml) at steady state of 6.47 +/- 1.51, a maximum steady-state concentration of 12.74 +/- 1.60, and a minimum steady-state concentration of 1.43 +/- 0.57, a dosage of 5 mg/kg every 8 hours is recommended. Serum urea nitrogen, serum creatinine, and the fractional clearance of sodium sulfanilate were determined before and after GT treatment. Renal function remained within the base-line range during 7 days of GT administration.  相似文献   
73.
Carbaryl was extracted from aged samples of rice, maize, peas and sunflower seeds using hexane, acetone and methanol. The quantities of insecticide extracted from the grain by acetone and methanol were much higher than that extracted by hexane for all four products. Methanol extracted higher levels of carbaryl than acetone from maize and peas but for rice and sunflower seeds the results were similar for the two solvents. Extraction by simply standing the whole grain in solvent for 48 h generally resulted in similar extracted levels of carbaryl to those obtained using more exhaustive techniques, such as grinding the grain or Soxhlet extraction. However, grinding or Soxhlet extraction removed the pesticide from the grain more rapidly.  相似文献   
74.
Abstract: An 8‐year‐old female spayed domestic shorthair cat had an abdominal mass palpated as an incidental finding on physical examination. Cytologic findings in ultrasound‐guided fine‐needle aspirates of the mass were most compatible with a sarcoma, with abundant mineralized material and mixed inflammation. The mass was removed surgically and on gross examination was white‐tan, firm, associated with the mesentery, and when transected contained a gauze sponge in its center. On histopathologic examination, an area of central necrosis with mineralization and numerous refractile fibers consistent with sponge material was surrounded by dense fibrous connective tissue (gossypiboma). Within the connective tissue was a population of highly pleomorphic spindle cells consistent with a fibrosarcoma. Immunohistochemically, most neoplastic cells stained strongly positive for vimentin and a low number of cells were positive for smooth muscle actin. The results were consistent with a fibrosarcoma arising at the site of a retained surgical sponge. At a follow‐up visit 2 months postoperatively, ultrasonographic and cytologic evidence of metastasis was found in the spleen and mesentery. To our knowledge, this is the first report of malignant transformation at the site of a retained surgical sponge in a cat and the first report of a fibrosarcoma arising within a gossypiboma in a domestic animal.  相似文献   
75.
76.
Integrated pest management includes the use of various pesticides that can have a detrimental effect on spiders. A pesticide can express its activity directly or via residues. Most of the attention paid to the impact of pesticides on spiders has investigated the effects of direct exposure. Our aim in this study was to investigate the residual activity (repellency and toxicity) of selected pesticides on six principal species of spider occurring in an apple orchard. Four of these species (Clubiona spp., Pardosa spp., Philodromus spp., Xysticus spp.) are hunting spiders, and two species (Dictyna spp., Theridion spp.) are web-building. We were interested to see whether these spiders could avoid a surface with residues and to examine their susceptibilities to fresh and 1-day-old residues. For this purpose we conducted laboratory experiments using three types of pesticide, an organophosphate, phosalone (Zolone), a pyrethroid, permethrin (Ambush) and Bacillus thuringiensis (Bt; Novodor), which were applied to paper discs or branches. Spiders could choose to stay on any treated paper/branch within a dish. Except for Theridion spp., all species were repelled by fresh residues but not by 1-day-old residues. Clubiona spp., Dictyna spp., Pardosa spp. and Xysticus spp were repelled by phosalone and permethrin residues only, whereas Philodromus spp. specimens were repelled also by Bt residues. Theridion spp. avoided contact with residues by making a web on any available branch. Regarding toxicity, neither fresh nor 1-day-old residues of phosalone or Bt caused significant mortality to any spider species. In contrast, both fresh and 1-day-old residues of permethrin caused significant mortality to all species except for Theridion spp. In conclusion, spiders can recognise and avoid only fresh residues, although older residues might still be toxic to them.  相似文献   
77.
Neospora caninum is one of the most important causes of abortion in cows. The occurrence of N. caninum infection in beef and dairy cattle has been reported worldwide, and in most provinces in Canada. The objective of this review is to summarize our current understanding of N. caninum in dairy and beef cattle for Canadian bovine practitioners. The review covers the life cycle of the agent, its mechanisms of transmission, clinical signs, and tests for diagnosing the infection. Data on the prevalence of the infection in Canadian dairy and beef cattle are reviewed and briefly compared with estimates from other parts of the world. Most importantly for Canadian bovine practitioners, the impacts of the infection, risk factors for its occurrence, and methods of control are also discussed. By reviewing the scientific literature on N. caninum from a Canadian perspective, culling decisions based on the interpretation of diagnostic tests are more effectively made in the control of N. caninum-associated disease.  相似文献   
78.
Until recently, none of the Mycobacterium bovis typing techniques permitted a satisfactory differentiation of isolates. During the last 10 years, the genome of pathogenic mycobacteria has been extensively studied, and phylogenetic analyses have shown that all (except Mycobacterium avium) belong to a single genetic species: the Mycobacterium tuberculosis complex. This increase in knowledge about the genome of these bacteria has lead to the discovery of molecular markers that allow us to differentiate isolates. Because of the phylogenetic proximity of the strains, even if most of these markers have been discovered in M. tuberculosis, they could be successfully adapted to the other bacteria of the M. tuberculosis complex, especially M. bovis. The most common markers in use today are the IS6110 insertion sequence, the direct repeat (DR) region, the poly(GC) rich (PGRS) sequences and the variable number tandem repeats (VNTR) sequences. The corresponding typing techniques are briefly described, and current knowledge of polymorphism and marker stability is detailed. If molecular markers are to offer wide perspectives for field studies, these two characteristics (polymorphism and stability) must be taken into account when choosing the marker(s) used in a study. In this context, examples of the application of molecular typing techniques for M. bovis are reviewed, on the one hand with epidemiological studies for which the major problem is the comparison between isolates and, on the other, with more general studies about the population genetics of M. bovis in a given country, and about its history and its phylogeny.  相似文献   
79.
In Algeria, cystic echinococcosis (CE) is a serious economic and public health problem. The common sheep/dog cycle is usually considered as the major source of human contamination. But to date the main strain of Echinococcus granulosus involved in the human contamination and the role of other hosts are still unknown. This paper reports an original work performed in northern Algeria combining field observations and molecular analysis. In a first step, examination of 6237 carcasses in slaughterhouses showed high infection and fertility rates in cattle and dromedaries. Then, in a second step, we used a molecular biology approach to identify the E. granulosus strain(s) involved. Forty-six samples from various origins were collected. They were analysed using comparison of PCR-amplified DNA sequences with one genomic (BG 1/3) and two mitochondrial (COI and NDI) targets. Results show the presence of a "sheep" strain of E. granulosus in North Algeria circulating between cattle and ovines and infectious to humans, whereas in South Algeria, a "camel" strain and a "sheep" strain were found to circulate in camels and in sheep, respectively. This study also reports an ambiguous genotype which resembled the "sheep" strain genotype (Gl) on the basis of the partial COI gene sequence, whereas on the basis of the partial NDI gene sequence, it was similar either to the "sheep" strain (Gl) or to the "camel" strain (G6). Besides its basic interest, our study confirms the role of other hosts (mainly cattle) in leading to transmission to humans and suggests that control measures should not only target sheep.  相似文献   
80.
Three field experiments were conducted on chickpea ( Cicer arietinum L.) and four on lentil ( Lens culinaris Med.) at different winter-sown rainfed locations in Jordan from 1988/89 to 1990/91 to study the effect of the duration of weed-free and weed-infested conditions on yields and yield components of the crops. Chickpea seed yields were reduced on average by 81 % and straw yields by 63 % when fields remained weed infested until harvest compared with weed-free conditions throughout the growing season. The corresponding lentil seed and straw yield decreases were 63 % and 55 %. As the duration of weed-free period increased and the duration of weed-infested period decreased, yields increased. However, the critical period of weed interference was between 35 and 49 days after emergence in chickpea and between 49 and 56 days after emergence in lentil, when these crops were at an advanced stage of vegetative growth. There were significant negative correlations between the weed dry weight and the seed or straw yields. The reduction in seed yields in both crops because of weed interference occurred mainly through the reduced number of pods /plant, which in turn was partly the result of reduced number of secondary branches. In chickpea, some reduction also occurred through reduced 100-seed weight.  相似文献   
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