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981.
982.
Acrylamide is a probable carcinogen found in processed potato products. The compound is formed at elevated temperatures by the Maillard reaction from two primary precursors - reducing sugars (fructose and glucose) and asparagine. Significant advances have been made in reducing acrylamide formation by selecting varieties with low precursor concentrations through conventional breeding or genetic modification techniques. However, acrylamide in many of the traditional varieties processed for fries or chips is sometimes found at elevated levels. Both agronomic and storage practices can significantly influence glucose, fructose, and asparagine concentrations and therefore the potential to form acrylamide during processing. This summary of a symposium presentation given at the 99th Annual Potato Association of American Meeting is to provide a general overview of previous studies that have examined the effects of agronomic factors such as nutrient and water management and storage factors such as temperature and duration on acrylamide precursors and/or acrylamide in processed potato products. A better understanding of how these factors affect acrylamide precursors is a first step in minimizing acrylamide formation during processing and improving the quality of processed potato products.  相似文献   
983.
Lisa zhang 《国际木业》2009,39(9):14-14
来自全球连锁建材超市家得宝(home depot),从2007年以来开始,在中国开拓了中国市场零售业务。目前在北京、天津、西安、郑州、等区域有10家店面经营建材商品的业务。他们在“可持续发展”议题上的做法,值得重视。因为在“渠道为王”的时代,渠道商的合力,或许将左右木制品的发展方向……  相似文献   
984.
The effects of altered water temperature in vivo on in vitro smooth muscle contractility of rainbow trout intestine were investigated. Temperature has a significant effect on receptor-mediated intestinal smooth muscle contractility in the rainbow trout. The efficacy of 5-HT, carbachol, and transmural stimulation increased with temperatures above 10°C, with an optimal increase at 15°C. There was also a modest increase in the potency of 5-HT and carbachol within 2 days of establishing trout at 20°C. By day 8, most of these changes had either stabilized or were returning to control values, suggesting that acclimation changes in membranes and enzyme activities were taking effect. However, the contractile responses to carbachol and transmural stimulation were still increasing at this time. This may imply that the muscarinic receptors are more resistant to membrane acclimation changes and may take longer to adapt. Because these experiments were controlled for handling stress and seasonal changes that affect contractility, we have been able to demonstrate some early changes in smooth muscle contractility that occur during acclimation to altered temperature.  相似文献   
985.
The effects of altered temperature in vivo on in vitro smooth muscle contractility of rainbow trout intestine were investigated. Initial analysis of the data revealed a seasonal variation in the maximal tension of intestinal smooth muscle attainable with 5-hydroxytryptamine (serotonin), carbachol, KCl, and transmural stimulation in vitro. Peaks occurred in spring and troughs in autumn. There was no seasonal cycling of the potency of the stimulants. All data regarding the efficacy of the stimulants were subsequently corrected for seasonal variation. The response of smooth muscle depends on the temperature of the water in which the fish are placed (2°C−20°C). There was a marked linear increase in efficacy and a slight increase in potency of the stimulants with increasing temperature. Changes in responsiveness of the intestinal smooth muscle occurred within 30 min of moving the fish between tanks. Smooth muscle reactivity returned to pretreatment values by 48h. Any changes in responsiveness with regards to time were unlikely to be as a consequence of water temperature, but may have been a result of handling stress.  相似文献   
986.
987.
988.
Ten dogs were given mitoxantrone at a dose of 5 mg/m2 body surface area intravenously. Recombinant canine granulocyte colony-stimulating factor (rcG-CSF) was administered subcutaneously daily for 20 days after an infusion of mitoxantrone in five of these dogs to determine the effect of the hematopoietic growth factor on the duration and severity of myelosuppression. The median neutrophil counts dropped below normal (less than 3,000/uL) for 2 days in the dogs that received rcG-CSF, and for 5 days in the dogs that received only mitoxantrone. Four of five dogs not treated with rcG-CSF and none of those receiving rcG-CSF developed serious neutropenia (less than 1,500/uL). The neutrophil counts were significantly (P less than 0.05) higher in the rcG-CSF treated dogs at all time points except before the administration of the colony-stimulating factor, and the sixth day after the mitoxantrone was administered. These findings demonstrate that rcG-CSF is capable of reducing the duration and severity of mitoxantrone-induced myelosuppression.  相似文献   
989.
990.
OBJECTIVES: To determine the requirement for 2nd surgical interventions and mortality after 3 different surgical techniques (percutaneous tube cystostomy [10 goats], surgical tube cystostomy [25 goats], urinary bladder marsupialization [10 goats]) for caprine obstructive urolithiasis, and to determine whether pre- or 24-hour postoperative physical examination findings or serum chemistry results could be used as predictors of mortality. STUDY DESIGN: Retrospective study. ANIMALS: Male goats (45) with obstructive urolithiasis. METHODS: Medical records for all male goats admitted and operated for obstructive urolithiasis between 1993 and 2003 were reviewed. Data retrieved included signalment, pre- and 24-hour postoperative values for temperature, pulse, respiratory rate, packed cell volume, serum K(+), serum creatinine, and blood urea nitrogen [BUN]. The type of initial surgical procedure, time to 2nd surgical intervention, time to death, and duration and cost of hospitalization were also obtained. RESULTS: Percutaneous tube cystostomy was associated with a significantly increased requirement for (5.6-fold increased hazard) and decreased time to a 2nd intervention (P=.002). There were no differences between the 3 procedures for time to mortality. Increased BUN and respiratory rate at admission were associated with increased mortality (hazards ratio of 4.8 and 5.0, respectively). Urinary bladder marsupialization was associated with significantly decreased hospitalization time (P=.02) and cost (P=.04) compared with surgical tube cystostomy and percutaneous tube cystostomy. CONCLUSION: Surgical tube cystostomy and bladder marsupialization are both acceptable surgical methods for treatment of caprine obstructive urolithiasis. Each procedure has inherent complications that should be discussed with the owner before choosing the surgical treatment. CLINICAL RELEVANCE: There are acceptable options for treatment of caprine obstructive urolithiasis; however, percutaneous tube cystostomy should be avoided.  相似文献   
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