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101.
Marine sponges harbor diverse microbial communities that represent a significant source of natural products. In the present study, extracts of 21 sponge-associated bacteria were screened for their antimicrobial and anticancer activity, and their genomes were mined for secondary metabolite biosynthetic gene clusters (BGCs). Phylogenetic analysis assigned the strains to four major phyla in the sponge microbiome, namely Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes. Bioassays identified one extract with anti-methicillin-resistant Staphylococcus aureus (MRSA) activity, and more than 70% of the total extracts had a moderate to high cytotoxicity. The most active extracts were derived from the Proteobacteria and Actinobacteria, prominent for producing bioactive substances. The strong bioactivity potential of the aforementioned strains was also evident in the abundance of BGCs, which encoded mainly beta-lactones, bacteriocins, non-ribosomal peptide synthetases (NRPS), terpenes, and siderophores. Gene-trait matching was performed for the most active strains, aiming at linking their biosynthetic potential with the experimental results. Genetic associations were established for the anti-MRSA and cytotoxic phenotypes based on the similarity of the detected BGCs with BGCs encoding natural products with known bioactivity. Overall, our study highlights the significance of combining in vitro and in silico approaches in the search of novel natural products of pharmaceutical interest.  相似文献   
102.
103.
The aims of this study were to assess the pharmacokinetics and pharmacokinetic/pharmacodynamic (PK/PD) indices predictive of clinical outcome of ciprofloxacin (CIP) and norfloxacin (NOR) after multiple oral dosing, and to investigate their penetration into prostatic fluid in dogs. Eight dogs received seven oral doses b.i.d. of NOR (20 mg/kg) and CIP (15 mg/kg). Drug concentrations were determined in blood and in two prostatic fluid samples. Prostatic fluid concentrations were lower than plasma concentrations for both drugs. No statistically significant differences were determined between the pharmacokinetic parameters calculated after the first and seventh doses for either CIP or NOR. The PK/PD indices were found to be useful for predicting bacteriological outcome for fluoroquinolones (area under the disposition curve/minimum inhibitory concentration [MIC] and peak plasma concentration/MIC) and indicate that with this dose regimen CIP presents a more favourable disposition than NOR for successful clinical outcome.  相似文献   
104.
Normal rat peritoneal exudate cells adhere to new-born Trichinella spiralis larvae in the presence of specific antibodies produced during the course of an oral infection. After 24 hours incubation with the peritoneal cells and antibodies most of the larvae were killed. Heated immune serum had less activity. With normal serum no adherence was observed. In order to investigate the influence of antibodies on new-born larvae in vivo, larvae were pre-treated in vitro with immune serum and then inoculated intravenously into normal mice. After 30 days the yield of normal larvae was 50% of the number recovered in a control group infected with non-treated new-born larvae.  相似文献   
105.
Trichophyton benhamiae was diagnosed in a 9-year-old female dog by histopathological evaluation, fungal culture and confirmation by sequencing of the internal transcribed spacer region of ribosomal DNA. Successful therapy was achieved with itraconazole, bathing with miconazole and chlorhexidine shampoo, and topical application of sodium hypochlorite as a rinse.  相似文献   
106.
The objective of the experiment was to compare the use of a PGF2α analogue (Cloprostenol) IM, with an intravaginal progestagen sponge, flurogestone acetate (FGA), and equine chorionic gonadotropin (eCG) IM application protocol. A total of 30 cyclical hair ewes (54.07?±?0.5 kg live weight, body condition score 3.5?±?0.5, and age 3?±?1 years) were used. For the control group ewes (n?=?15), intravaginal sponges (IS) impregnated with 20 mg of FGA were inserted for 12 days with 500 IU of eCG IM at sponges withdrawal. For the PG group ewes (Treatment group n?=?15), two injections of Cloprostenol (75 mcg) were given 12 days apart. The presence of estrus was detected using two rams with 8 h interval beginning at the end of the treatment. Progesterone concentrations in blood were measured by solid phase radioimmunoassay. A student’s t test was performed to analyze the duration of estrus and the interval between the ends of the treatment and the onset of estrus (ET-OE) presentation. Progesterone levels were compared with two-way ANOVA, with treatment, and day of menstrual cycle as fixed factors. Treatment costs ratio was calculated by dividing the total costs of FGA IS application between total costs of Cloprostenol application. Significant differences (P?P?相似文献   
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108.
Ultraviolet light analysis of a fossil of the theropod dinosaur Scipionyx samniticus revealed that the liver subdivided the visceral cavity into distinct anterior pleuropericardial and posterior abdominal regions. In addition, Scipionyx apparently had diaphragmatic musculature and a dorsally attached posterior colon. These features provide evidence that diaphragm-assisted lung ventilation was present in theropods and that these dinosaurs may have used a pattern of exercise physiology unlike that in any group of living tetrapods.  相似文献   
109.
The dissolution of heat-induced beta-lactoglobulin (betaLg) gels in alkaline solution plays an important role in the cleaning-in-place of fouled dairy and other food plants. The dissolution behavior is strongly influenced by the conditions under which the gel is formed. At low alkaline pH values (<13), the dissolution rate constant kg' decreases with longer gelation time and higher temperature. An inverse relationship is observed between the kg' value and the amount of covalently cross-linked proteins in the gel, which is mainly due to disulfide bonds. beta-Elimination kinetics of intramolecular cystines in betaLg have been used to estimate the amount of intermolecular disulfide bonds that are cleaved during dissolution. The results call into question current dissolution models for these systems based on external mass transfer through the fluid next to the swollen gel. At low temperatures, the amount of disulfide cleavage is estimated to be small, indicating that dissolution is likely to involve the (slow) disengagement of large protein clusters, analogous to the dissolution of synthetic polymers.  相似文献   
110.
The electrochemical elimination of the herbicide diquat dibromide (DQ) in an undivided electrochemical cell (Condiacell®-type cell) and an H-type cell (a divided electrochemical cell) using boron-doped diamond (BDD) electrodes is reported for the first time. The degradation of essentially 100% of the DQ present was achieved in the undivided electrochemical cell and ca. 92% in the H-type cell. Nearly 80% of the total organic carbon (TOC) and of the chemical oxygen demand (COD) were removed after 5 h of treatment at different current densities (i.e., 0.5, 1.0, and 1.5 mA/cm2 for the undivided cell, and 2.5, 5.0, and 7.5 mA/cm2 for the H-type cell) with a maximum specific energy consumption of approximately 150 kWh kg?1 of COD degraded in the undivided cell, and 300 kWh kg?1 of COD in the H-type cell. Energy consumption of about 0.30 kWh g?1 of TOC occurred in the undivided electrochemical cell and 2.0 in the H-type cell. In spite of obtaining similar percentages of DQ degradation and of COD and TOC removal, a smaller energy usage was required in the undivided cell since smaller current densities were employed. Best results were obtained with the undivided cell, since it required a smaller current density to obtain virtually the same percentage of DQ degradation and removal of COD and TOC. The results obtained herein show that the use of electrochemical advanced oxidation processes may be a good alternative for DQ degradation in polluted water.  相似文献   
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