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81.
OBJECTIVE: The aim of this study was to determine the food sources and acquisition practices used by homeless youth in Adelaide. This work is part of a larger study that aimed to examine the extent and nature of food insecurity among homeless youth. DESIGN: Cross-sectional design involving quantitative and qualitative methods. SETTING: Four health and welfare inner-city agencies serving homeless youth in Adelaide, South Australia. SUBJECTS: A sample of 150 homeless youth aged between 15 and 24 years recruited from these agencies. Fifteen were selected via snowball sampling for interview. RESULTS: Use of welfare food sources was high (63%). Food from welfare agencies was supplemented by unorthodox food acquisition methods such as theft (65%), begging for money for food (61%), begging for food items (44%) and asking for help from friends and relatives (34%). Reasons given for non-usage of welfare food services included affordability, access, being too busy, shame or embarrassment. CONCLUSIONS: Food insecurity is a salient issue for some homeless youth in Adelaide. Clarifying food acquisition practices of food-insecure homeless youth is essential for rational planning and improvement of food-related services to meet their needs. Such an understanding also underpins the development of broader public policy responses that improve individual and household skills and resources to acquire food and ensure food security. Nutrition professionals, welfare professionals and policy-makers need to work sensitively with welfare food agencies and others to improve food access and food security for homeless youth.  相似文献   
82.
Parvalbumin is a calcium-binding muscle protein that is highly conserved across fish species and amphibians. It is the major cross-reactive allergen associated with both fish and frog allergy. We used two-dimensional electrophoretic and immunoblotting techniques to investigate the utility of a commercial monoclonal anti-frog parvalbumin IgG for detecting parvalbumin present in some commonly consumed fish species. The 2D electrophoresis and immunoblots revealed species-specific differences in proteins that appear to represent various numbers of isoforms of parvalbumin in carp (5), catfish (3), cod (1) and tilapia (2). No parvalbumin was detected in yellowfin tuna. Based on minor differences in relative intensities of protein staining and immunodetection, parvalbumin isoforms may have slight differences in the epitope region recognized by the anti-frog parvalbumin antibody. These results suggest that the frog anti-parvalbumin antibody can be used as a valuable tool to detect parvalbumins from the fish tested in this study, except yellowfin tuna.  相似文献   
83.
Plant litter and fine roots are important carbon (C) inputs to soil and a direct source of CO2 to the atmosphere. Solid-state carbon-13 nuclear magnetic resonance (13C-NMR) spectroscopy was used to investigate the nature of C changes during decomposition of plant litter and fine roots of mulga (Acacia aneura F. Muell. Ex. Benth.), wheat (Triticum aestivum L.), lucerne (Medicago sativa) and buffel grass (Cenchrus ciliaris) over an 18-month period. Alkyl C was closely associated with total N concentrations in all litter materials during decay and as alkyl C increased so did total N, indicating an increase in refractory biomacromolecules. Mulga phyllodes had the greatest alkyl C concentration of all litter and fine root materials, and also exhibited the NMR peaks assigned to tannins that may slow or hinder decomposition rates and nitrification. Mulga litter and fine roots decomposed slower than all other litter materials and the soil under mulga had the highest soil C concentration, indicating slower CO2 release. The alkyl C-to-O-alkyl C ratio is generally used as an index of the extent of decomposition, but is not useful for the decay of woody components. Of all the NMR ratios studied that may indicate the extent of decomposition, the carbohydrate C-to-methoxyl C ratio proved to have the strongest and most consistent relationship with decay time, fraction of mass remaining and total C, even though increases in alkyl C were observed with decreases in carbohydrate C.  相似文献   
84.
The ventral spinal root origin of the radial nerve, its muscle branches, and brachial plexus nerves which supply shoulder and thoracic musculature was determined in the dog. Electrophysiological signal averaging techniques measured evoked potential from specific ventral spinal roots to individual muscle nerves. The entire radial nerve received input from the sixth cervical (C6) through the second thoracic (T2) spinal roots. The most significant (p less than .05) input to triceps brachii came from C8 while the deep ramus of the radial nerve received its largest input from C7. The brachiocephalicus, suprascapular, and subscapular nerves all received their most significant (p less than .05) innervation from C6. Approximately 90% of the evoked potential to the axillary nerve originated from C7. The thoracodorsal nerve received most of its innervation from ventral roots C7 and C8. The lateral thoracic nerve which innervates the cutaneous trunci muscle was supplied by ventral roots C8-T2. Examination of innervation patterns suggests that only modest variation of spinal root input to specific nerves occurred between individual dogs.  相似文献   
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The equine head is an anatomically complex area, therefore advanced tomographic imaging techniques, such as computed tomography or magnetic resonance imaging (MRI), are often required for diagnosis and treatment planning. The purpose of this multicenter retrospective study was to describe MRI characteristics for a large sample of horses with head disorders. Horses imaged over a period of 13 years were recruited. Eighty‐four horses met the inclusion criteria, having neurological (n = 65), sinonasal (n = 14), and soft tissue (n = 5) disorders. Magnetic resonance imaging accurately depicted the anatomy and allowed identification of the primary lesion and associated changes. There were good correlations between MRI findings and intraoperative or postmortem results. Magnetic resonance imaging showed the exact localization of the lesions, their size, and relation to surrounding structures. However, in the neurological group, there were 45 horses with no MRI abnormalities, 29 of which had a history of recurrent seizures, related to cryptogenic epilepsy. Magnetic resonance imaging was otherwise a valuable diagnostic tool, and can be used for studying a broad range of head disorders using either low‐field or high‐field magnets.  相似文献   
88.
OBJECTIVE: To evaluate safety and efficacy of LDI-100, a preparation containing human chorionic gonadotropin (hCG) and bacillus Calmette-Guerin (BCG), in the treatment of dogs with mast cell tumors and to compare results with those from a control group receiving single-agent vinblastine. ANIMALS: 95 dogs with measurable grade II or III mast cell tumors. PROCEDURES: Dogs were randomized to receive either LDI-100 (1.35 ng of BCG and 2 units of hCG, SC, q 24 h) or vinblastine (2 mg/m(2), IV, q 1 wk) for 6 weeks. Tumors were measured at baseline and day 42, and dogs were monitored for signs of toxicosis. Clinical performance scores were recorded at each visit. Differences in host factors (sex, weight, and age), clinical performance score, tumor response, and adverse events were analyzed. RESULTS: 46 dogs received LDI-100, and 49 dogs received vinblastine. No significant differences were found between the 2 treatment groups with regard to host factors or clinical performance score. Tumor response (>or=50% reduction) rates were similar between the LDI-100 and vinblastine group (28.6% and 11.7%, respectively). Dogs in the LDI-100 group had significantly less neutropenia than the vinblastine group. CONCLUSIONS AND CLINICAL RELEVANCE: hCG and BCG have immunomodulatory and antitumor effects against a variety of malignancies in humans and dogs. In this study, LDI-100 provided clinical responses comparable to single-agent vinblastine chemotherapy but without myelosuppression. LDI-100 is a promising new agent that should be further investigated for multimodality therapy of mast cell tumors in dogs.  相似文献   
89.
The need for microgram quantities of RNA for microarray experiments has hindered application of this novel technology in cell types/tissue samples with limited abundance of RNA. In this study, potential application of T7-based linear RNA amplification was investigated for use in gene expression profiling experiments where starting material is limited. Yield and integrity of amplified antisense RNA (aaRNA), microarray hybridization intensities, and fidelity of differential gene expression detected were determined for arrays generated for unamplified versus amplified RNA from the same homogenous starting pools. Total RNA was extracted from bovine spleen and fetal ovary, serially diluted to concentrations ranging from 2 microg to 500 pg and amplified. Quality and quantity of total input RNA and aaRNA were assessed by spectrophotometry, gel electrophoresis and bioanalyzer. In experiment 1, we determined the optimal amounts of aaRNA generated from 20, 40, 200 ng and 2 microg input total RNA for use in cDNA synthesis, labeling and array hybridization that would yield robust and consistent hybridization signals on a bovine oocyte cDNA microarray. In experiment 2, comparison of microarray hybridization intensities and fidelity of differential gene expression between aaRNA generated from 2, 20 and 40 ng input total RNA versus unamplified RNA (uRNA) were conducted. The hybridization intensities for each of the 7000 spots per slide for microarrays conducted using aaRNA versus uRNA were highly correlated (2 ng = 0.84, 20 ng = 0.88, 40 ng = 0.90; P < 0.01). The false positive rate was low and similar (4.0% versus 4.4%) for arrays done with uRNA and aaRNA. Ninety-seven ESTs were detected as differentially expressed in the fetal ovary versus spleen at > 1.5- or < 0.5-fold using uRNA (P < 0.05). However, the number of genes detected in arrays using aaRNA was approximately 1.5-2.5 times greater than with uRNA. Approximately, 65-70% of differentially expressed genes were common between uRNA and aaRNA arrays. Relative fold-expression (Cy3/Cy5 ratios) for 25 overlapping abundant genes was comparable for uRNA versus aaRNA arrays with 2 and 20 ng total RNA as input. Results demonstrate that T7-based linear amplification of small amounts of input RNA and use of aaRNA in microarray experiments retains fidelity of detection of differential gene expression that is relatively comparable to experiments done with uRNA and provides a potentially viable approach to facilitate gene expression profiling using limited amounts of starting material.  相似文献   
90.
Objective To evaluate disposition of a single dose of butorphanol in goats after intravenous (IV) and intramuscular (IM) administration and to relate behavioral changes after butorphanol administration with plasma concentrations. Design Randomized experimental study. Animals Six healthy 3‐year‐old neutered goats (one male and five female) weighing 46.5 ± 10.5 kg (mean ± D). Methods Goats were given IV and IM butorphanol (0.1 mg kg?1) using a randomized cross‐over design with a 1‐week interval between treatments. Heparinized blood samples were collected at fixed intervals for subsequent determination of plasma butorphanol concentrations using an enzyme linked immunosorbent assay (ELISA). Pharmacokinetic values (volume of distribution at steady state [VdSS], systemic clearance [ClTB], extrapolated peak plasma concentration [C0] or estimated peak plasma concentration [CMAX], time to estimated peak plasma concentration [TMAX], distribution and elimination half‐lives [t1/2], and bioavailability) were calculated. Behavior was subjectively scored. A two‐tailed paired t‐test was used to compare the elimination half‐lives after IV and IM administration. Behavioral scores are reported as median (range). A Friedman Rank Sums test adjusted for ties was used to analyze the behavioral scores. A logit model was used to determine the effect of time and concentration on behavior. A value of p < 0.05 was considered significant. Results Volume of distribution at steady state after IV administration of butorphanol was 1.27 ± 0.73 L kg?1, and ClTB was 0.0096 ± 0.0024 L kg?1 minute?1. Extrapolated C0 of butorphanol after IV administration was 146.5 ± 49.8 ng mL?1. Estimated CMAX after IM administration of butorphanol was 54.98 ± 14.60 ng mL?1, and TMAX was 16.2 ± 5.2 minutes; bioavailability was 82 ± 41%. Elimination half‐life of butorphanol was 1.87 ± 1.49 and 2.75 ± 1.93 hours for IV and IM administration, respectively. Goats became hyperactive after butorphanol administration within the first 5 minutes after administration. Behavioral scores for goats were significantly different from baseline at 15 minutes after IV administration and at 15 and 30 minutes after IM administration. Both time and plasma butorphanol concentration were predictors of behavior. Behavioral scores of all goats had returned to baseline by 120 minutes after IV administration and by 240 minutes after IM administration. Conclusions and Clinical Relevance The dose of butorphanol (0.1 mg kg?1, IV or IM) being used clinically to treat postoperative pain in goats has an elimination half‐life of 1.87 and 2.75 hours, respectively. Nonpainful goats become transiently excited after IV and IM administration of butorphanol. Clinical trials to validate the efficacy of butorphanol as an analgesic in goats are needed.  相似文献   
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