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31.
Effects of formulation on the textural stability of intermediate‐moisture, flour‐based, “jerky”‐type extrudates were assessed. Potato‐based extrudates containing various particulate‐meat concentrations and different plasticizers (sucrose, fructose, glycerol, and glucose) were produced and subjected to accelerated storage for three weeks. The elastic modulus of the samples was measured before storage and then weekly. The relative fluidity and moisture mobility of the specimens were assessed by dynamic mechanical spectrometry (DMS), electron spin resonance (ESR), and nuclear magnetic resonance (NMR). Samples were also evaluated by fluorometry and X‐ray diffraction to determine the extent of browning reaction and degree of molecular ordering, respectively. While elastic modulus increased appreciably during storage, firming was progressively reduced by entrained meat content and also by plasticizers, especially glycerol; plasticized and meat‐containing samples had correspondingly lower tan δ peak temperatures as measured by DMS. Textural results were also in keeping with fluidity and local viscosity as assessed by ESR measurements. NMR T1 relaxation values, reflecting moisture mobility, increased during storage. Diffraction spectra were consistent with published observations of hydrated starch, suggesting that water may have been released due to increased association of proteinaceous constituents. Fluorescence measurements confirmed moderate Maillard browning in all samples and significant chlorogenic browning in glucose‐containing samples, although these effects were unrelated to degree of firming. It was concluded that textural stability was optimized by interruption of the matrix by dispersed meat or by plasticization by low molecular weight constituents.  相似文献   
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White yam (Dioscorea rotundata) is an important tuber crop of West Africa and the Caribbean, and one of the key limiting factors in its production is the availability of good quality planting material. The Adaptive Yam Minisett Technique (AYMT) was designed to help overcome this constraint. The paper presents an analysis of agronomic and economic data collected across four years (2013 to 2016) of AYMT plots planted in two areas within the middle-belt of Nigeria. Of the 136 plots that were established, 11% were lost to flooding and damage from Fulani cattle. Mean yield was 13.16 t/ha, 17,747 tubers/ha and the mean tuber weight was 0.73 kg. Plot yield declined with an increase in planting time, while plots owned by female farmers were on average planted later than those owned by their male counterparts; this helps explain the effect of gender noted in a previous study. Differences in yield were also noted between the two areas, which could also partly be explained by differences in planting time. The plots were profitable, with a mean cost over the four years of Naira 915,196/ha, revenue of Naira 3,197,786/ha and gross margin of Naira 2,282,591/ha (equivalent to US$4,039, US$14,319 and US$10,280 respectively). The main factor influencing costs and revenue was year, with no effect of gender. There is a need for more research on planting time in AYMT and how it interacts with factors, such as yam variety.  相似文献   
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The goal of this study was to determine the prevalence of gastric ulcers in horses with acute abdominal crisis (colic) and to examine the temporal effect of hospitalization on ulcer development in equine patients treated for colic. In addition, other factors that may be associated with gastric ulceration were also explored. The study design was a prospective original study incorporating 169 horses that presented to the George D. Widener Hospital for examination. One hundred and twelve horses presenting with the chief complaint of colic were included in the study group, and 57 horses that presented for non-colic or nonemergency complaints were evaluated and included as case controls. Gastroscopy was performed on equine patients presenting with the chief complaint of colic or horses presenting for reasons other than colic (control); mucosal changes were scored 0 to 3. Additionally, horses presenting for colic were gastroscopically evaluated twice during a 5-day period. Medical records were reviewed for history, clinical findings, laboratory results, and treatment. Seventy-six of 112 horses presenting with the chief complaint of colic had gastric ulceration compared with 41 of 57 horses in the control group. There was a significant association between age of the patient and chief complaint (ie, colic vs control) and between breed and chief complaint. There was no association between gastric ulcer score and chief complaint (colic vs control). Thirty-eight of the 112 horses presenting with colic deteriorated in ulcer score while hospitalized. Using a Pearson chi-squared test, there was no statistically significant association between gastric ulceration with age, breed, or sex. Horses with gastric ulceration in the colic group had lower packed cell volumes compared with horses presenting with colic without gastric ulcers, and this was statistically significant (P < .001). The high incidence of gastric ulceration in the study and control groups supports the reports of other investigators that gastric ulcers in horses, no matter the presenting complaint, are widespread. There was a significant association between breed and chief complaint (P = .005); however, breed and outcome of gastric ulceration were not related (Thoroughbreds were the least likely breed to present for colic). Although a trend in increasing gastric ulceration was seen in hospitalized colic patients, it was not statistically significant. This suggests that horses that are hospitalized may be at increased risk for developing gastric ulcers because of stress, feed deprivation, and administration of treatment. Thus, horses that present for colic should be gastroscopically evaluated if clinical signs raise the index of suspicion for gastric ulceration.  相似文献   
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Oilseed rape yield potential could be improved lengthening the duration of the late reproductive phase by increasing the number of grains per unit area. Photoperiod sensitivity could be used as a tool to manipulate the reproductive phase and thereby the number of grains. The aim of this study was to assess (i) the effects of different combinations of photoperiod on the duration of different phases and (ii) analyze how the changes in that duration affect yield (and its components) as well as oil seed content in oilseed rape. Field experiments were conducted in a factorial combination of three cultivars and three photoperiod regimes: natural photoperiod (NP) which represents the control and extended photoperiod of 6 h over NP (NP + 6) during emergence (E)-flower buds visible (FBV) and FBV-maturity (M) arranged in a randomized complete block design with three replicates, during two years representing three environments. Results showed that oilseed rape evidenced photoperiod responses during vegetative and early reproductive phases. Due to the lack of correlation between the duration of the vegetative and reproductive phases, it is possible to speculate the vegetative period may be altered independently of the modification of the rest of the phases. The positive relationship between grain number per m2 and the duration of the late reproductive phase suggests that yield could be increased by lengthening the duration of that phase. Thus, regardless of the effect on the previous phase, the photoperiod sensitivity found in the early reproductive phase opens the possibility to manipulate the relative durations of vegetative and reproductive phases. Therefore, the length of the reproductive phase will be increased at the expense of a reduction in the duration of the vegetative phase, but without changing the whole duration of the crop cycle. This strategy could increase yield in oilseed rape in the future. Variations in yield were mostly explained by changes in the grain number per unit area without significant correlation with grain weight. However, a negative relationship between grain weight and grain number was found, showing a slight counterbalance in yield, by decreasing the grain weight. Since oil concentration appeared to be a more conservative attribute, increases in crop yield through a higher grain number per unit area would be a suitable strategy for improving oil yield as no reductions in oil concentration can be expected.  相似文献   
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Herbs are a rich source of bioactive phytochemicals such as carotenoids, which are known to exert various positive biological effects. However, there is very limited information in the literature regarding the content and bioavailability of carotenoids from commonly consumed herbs. Therefore, the objectives of the present study were first, to determine the carotenoid content of eight herbs namely basil (Ocimum basilicum), coriander (Coriandrum sativum), dill (Anethum graveolens), mint (Metha L.), parsley (Petroselinum crispum), rosemary (Rosmarinus officinalis), sage (Salvia officinalis), and tarragon (Artemisia dracunculus L.); and second, to assess carotenoid bioaccessibility from these herbs using a simulated human in vitro digestion model. Carotenoid bioaccessibility is defined as the amount of carotenoids transferred to micelles after digestion when compared with the original amount present in the food. The content of individual carotenoids varied significantly among the herbs tested. Carotenoid bioaccessibility varied from 0 to 42.8%. Basil and coriander, and their respective micelles, contained the highest levels of β-carotene, β-cryptoxanthin, and lutein + zeaxanthin. Our findings show that herbs are rich sources of carotenoids and that these foods can significantly contribute to the intake of bioaccessible carotenoids.  相似文献   
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Rat‐associated zoonoses transmitted through faeces or urine are of particular concern for public health because environmental exposure in homes and businesses may be frequent and undetected. To identify times and locations with greater public health risks from rats, we investigated whether rat characteristics, environmental features, socioeconomic factors, or season could predict rat infection risk across diverse urban neighbourhoods. In partnership with a pest management company, we sampled rats in 13 community areas along an income gradient in Chicago, a large city where concern about rats has increased in recent years. We collected kidneys for Leptospira spp. testing and colon contents for aerobic bacteria such as Salmonella spp. and Escherichia coli. Of 202 sampled rats, 5% carried Leptospira spp. and 22% carried E. coli. Rats were significantly more likely to carry Leptospira spp. on blocks with more standing water complaints in higher‐income neighbourhoods (OR = 6.74, 95% CI: 1.54–29.39). Rats were significantly more likely to carry E. coli on blocks with more food vendors (OR = 9.94, 2.27–43.50) particularly in low‐income neighbourhoods (OR = 0.26, 0.09–0.82) and in the spring (OR = 15.96, 2.90–88.62). We detected a high diversity of E. coli serovars but none contained major virulence factors. These associations between environmental features related to sanitation and infection risk in rats support transmission through water for Leptospira spp. and faecal–oral transmission for E. coli. We also found opposing relationships between zoonotic infection risk and income for these two pathogens. Thus, our results highlight the importance of sanitation for predicting zoonotic disease risks and including diverse urban areas in pathogen surveillance to mitigate public health risks from rats.  相似文献   
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