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51.
The preparation of modified Mohs paste, commonly used for malignant wounds, requires time and effort. Moreover, metal-containing liquid waste is generated when malignant wounds are scrubbed. Therefore, we previously changed the base material of the modified Mohs paste from zinc oxide starch powder to carboxymethyl cellulose (CMC). The novel modified Mohs paste based on CMC (moM-CMC sol) may reduce these disadvantages. In the present study, the moM-CMC sol was applied to malignant tumors in three dogs to manage bleeding and malodor. The moM-CMC sol transitioned into a gel on the tumors within an hour of application and could be easily removed. The symptoms resolved in all cases. The moM-CMC sol could be beneficial for dogs with malignant wounds.  相似文献   
52.
O-[1-Ethyl-2-(3-trifluoromethylphenoxy)]ethyl-N-benzylcarbamate exhibits a marked inhibition of carotenoid biosynthesis. Forty-one analogues were synthesized and assayed for plant-type phytoene desaturase (PDS) and zeta-carotene desaturase (ZDS) inhibition in a cell-free system using recombinant enzymes obtained from Escherichia coli transformants. The target enzyme of all carbamates synthesized in this study is PDS and not ZDS; no inhibition of ZDS was observed using a 10(-4) M inhibitor concentration. Four compounds, O-[1-ethyl-2-(3-trifluoromethylphenoxy)]ethyl-N-(2-phenylethyl)carbamate (23), O-[1-ethyl-2-(3-trifluoromethylphenoxy)]ethyl-N-(2-chlorobenzyl)carbamate (25), O-[1-ethyl-2-(3-trifluoromethylphenoxy)]ethyl-N-(2-chlorobenzyl)carbamate (26), and O-[1-methyl-2-(3-trifluoromethylphenoxy)]ethyl-N-benzylcarbamate (30), were the most potent PDS inhibitors. Their pI(50) values, the negative logarithms of the molar concentration that produces a 50% inhibition, were 7.5, representing the same inhibitory activity as norflurazon. With respect to a structure-activity relationship the oxygen atom of the phenoxy group and a carbamate structure in O-(1-ethyl-2-phenoxy)ethyl-N-aralkylcarbamates studied were found to be essential for strong PDS inhibitors. Also, introduction of an ethyl group at the alpha-position of the ethylene bridge between the phenoxy group and the carbamate was important for a strong PDS inhibitor. Substituents at the 2- and/or 3-position of the phenoxybenzene ring were found to be favorable to a strong PDS inhibition of the analogues.  相似文献   
53.
The photoassimilate flow in an intact plant stem was imaged in real-time and its dynamics was quantitatively described using the Positron Emitting Tracer Imaging System (PETIS). Radioactive 11CO2 was fed to a leaf of an intact broad bean ( Vicia faba L.) plant, together with air containing an ambient concentration of non-radioactive carrier CO2 gas. Movies of flow of the 11C-labeled photoassimilates in the plant body were captured with PETIS. Here we demonstrate that the average flow speeds and the distribution ratios of photoassimilates in the respective nodes and internodes of the observed stem can be estimated by the transfer function analysis, one of the mathematical modeling methods. We also estimated the changes in the spatial distribution of the average flow speeds in the same stem when the fed leaf was exposed to enriched carrier CO2 gas.  相似文献   
54.
Abstract. The influence of pH and glucose on growth of the fish pathogenic fungus Ichthyophonus hoferi was measured by indirect conductimetry and microscopy. Using indirect conductimetry, distinct resistance curves were produced within 3 days at 15 †C, Conductimetric changes were enhanced when the media were supplemented with glucose. Low pH (3–4) was essential to ensure continuous growth of the fungus, which could be further facilitated by supplementation with glucose. At pH 7, growth occurred when the fungus had been pre-cultured at low pH. Growth of the fungus ceased after three successive transfers at pH 7 and this explains why earlier attempts to subculture have failed. Only vegetative stages of I. hoferi were observed; i.e. no conidia. At pH 7, growth was mainly observed as spherical bodies of varying size, with large numbers of nuclei, and thick-walled spherical multinucleate bodies. Hyphal growth was abundant at low pH. The alternating pH simulates the natural conditions experienced by the fungus on transfer from the stomach (low pH) to the muscle (neutral pH) and reproducible sub-culturing is obtained when mimicking this pH cycle or when a low pH is maintained.  相似文献   
55.
An ideal head‐immobilization method provides a high level of accuracy and reproducibility in the immobilization. Various head‐immobilization methods for radiotherapy have been published and are excellent in terms of accuracy; however, these methods are complicated to use, and labor intensive. The present study describes two new bite block‐type head‐immobilization devices designed for higher stability and lower vertical variation. The device designed in our previous study (the bite block‐type head‐immobilization device; Device A) was modified by making a groove on the top the horizontal plate (Device B) for a stable ventral‐dorsal position, or beneath the horizontal plate (Device C) for a stable dorsal‐ventral position. The three devices were objectively compared with respect to setup time, and accuracy of the computed tomography scan images by two authors independently. Five male healthy beagles were used in this study. For each device, the setup time and the variation in the coordinates were measured five times for each dog. The mean setup times for Devices A, B, and C were 3.3, 1.5, and 2.4 min, respectively, showing the groove modifications were able to reduce the setup time (in device B, by at least 50%). Moreover, three‐dimensional analysis of the computed tomography images revealed that the measurement variability of Device A (1.6 ± 1.0 mm) was significantly higher than that of Device C (0.7 ± 0.4 mm; P < 0.001). Collectively, our results show that use of a bite block‐type head‐immobilization device with a groove improves the setup time and head‐immobilization accuracy.  相似文献   
56.
Three electrophoretic variations (AA, BB and AB) of ovalbumin controlled by codominant alleles OvA and OvB have been observed in various chicken populations. We compared nucleotide sequences of the open reading frame between two alleles of ovalbumin gene. The difference between the two alleles was found as a non‐synonymous substitution of asparagine to aspartic acid as a result of AAT to GAT point mutation at position 8032–8034 in exon 8. We developed polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) protocol in combination with Mbo I restriction endnuclease mapping for the detection of this substitution. By the PCR‐RFLP the allelic frequency of the OvB was estimated to be within the range of 0.000–0.150 in 11 Asian indigenous chicken populations and 0.000 in four improved breeds used in the present study. Gene frequency, estimated by PCR‐RFLP in the present study, paralleled that obtained by protein polymorphisms of egg white. Thus, this study provides, for the first time, information of the occurrence of ovalbumin allele OvA and OvB in Asian indigenous chicken populations.  相似文献   
57.
A 2-month-old mix-breed calf developed acute blindness and ataxia. Serum thiamine concentration was deficient. In antemortem magnetic resonance imaging there were laminar T2-hyperintense regions extending along the cerebral cortex that primarily affected the gray matter. The lesions were relatively symmetric between the left and right hemispheres but no abnormalities were present at the frontal lobes. At necropsy, laminar autofluorescence of the cerebral cortex was observed under ultraviolet exposure at 365 nm, consistent with a diagnosis of polioencephalomalacia. Polioencephalomalacia in the bovine species is compared with that in other species, namely humans, dogs, and cats.  相似文献   
58.
In this study, by partial sequence analysis of the genome segments encoding VP5* and VP7, we characterized a novel bovine group A rotavirus, namely, Tak2, that was detected from adult cattle diarrhea in Tochigi Prefecture, Japan. The nucleotide (nt) and deduced amino acid (aa) sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 of Tak2 revealed a low identity with those of group A rotaviruses carrying previously published P and G type specificities (VP5*: nt identity, 61.6%-67.6% and aa identity, 58.0%-71.4%; half of the amino terminal portion of VP7: nt identity, 57.8%-73.5% and aa identity, 61.2%-70.9%). Additionally, phylogenetic analysis of the nt sequences of the genome segments encoding VP5* and half of the amino terminal portion of VP7 revealed that Tak2 formed a branch separate from the established P and G types. These results suggested that Tak2 could possess novel P and G types yet not reported among group A rotaviruses.  相似文献   
59.
Nitrification inhibitory activity of halomethyl-1,3,5-triazines was determined by measuring the inhibitory activities on ammonia-oxidation to nitrate (NO3-N) in an upland soil and on ammonia-oxidation to nitrite (NO2-N) by Nitrosomonas europaea ATCC 25978 (ATCC) and Nitrosomonas sp TK 794 (TK). Within the chlorinated trimethyl-1,3,5-triazines, those bearing at least one trichloromethyl group inhibited nitrification more strongly, both in soil and in cell suspension of ATCC, than other mono- or dichlorinated methyl-1,3,5-triazines. Introduction of an amino group to 2,4,6-tris(trichloromethyl)-1,3,5-triazine gave 10- and 100-fold increases of nitrification inhibitory activity in soil and ATCC cell culture, respectively. Within the trihalomethyl-1,3,5-triazines, those having tribromomethyl group(s) exhibited rather weaker nitrification inhibition in soil than the corresponding trichloromethyl-1,3,5-triazines, although they showed a strong inhibition in cell suspension. Ammonium oxidation in ATCC was inhibited more strongly than that in TK. In QSAR studies, the optimum log P values were calculated as c 4.30. By using this value it will become possible to design highly active trichloromethyl-1,3,5-triazine nitrification inhibitors.  相似文献   
60.
In the Japanese macaque, semen has been collected by electro-ejaculation (EE), using the higher voltage stimuli compared to other species including genus Macaca. Semen coagulates immediately after ejaculation, which makes difficult to produce high-quality semen for artificial insemination. Recently, semen collection using urethral catheterization (UC) has been reported in carnivore and this technique may allow semen collection without coagulation in a less invasive manner. Further, the temporal preservation temperature and cooling rate of semen during cryopreservation affect post thawing sperm quality. In this study, to improve semen quality and quantity, as well as the animal welfare, semen collection was performed by EE with high (5–15 V) or low (3–6 V) voltage, UC and a combination of the two (EE-UC). It has been suggested that a high voltage is necessary for semen collection, but 10 V stimulation was effective enough and 15 V is for additional sperm collection. Also, liquid semen was collected by EE-UC and this could increase the total number of sperm. Further, to improve the post thawing sperm motility, semen was kept at four temperatures (4, 15, 25 and 37°C) for 60 min, and processed with two cooling procedures (slow cooling before second dilution and fast cooling after second dilution). Holding semen at 25°C and fast cooling after the second dilution maintained progressive motile sperm rate. The present results will contribute to the improvement of semen collection and animal welfare of Japanese macaques.  相似文献   
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