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71.
The current study evaluated transgenic cotton lines with normal levels of gossypol/terpenoids in the vegetative and floral tissues, but with ultra‐low gossypol in the seeds as a replacement for glandless cottonseed meal (GCSM) and fishmeal. A 64‐day growth trial evaluated the ability of cottonseed meals from a natural glandless cotton variety/mutant, two transgenic Ultra‐low Gossypol Cottonseed (ULGCS) lines, a non‐transgenic parental control and a commercial variety, to replace 355 g kg?1 fishmeal in a diet containing 350 g kg?1 crude protein. Juvenile Litopenaeus vannamei (1.48 ± 0.29 g) were stocked (40 shrimp m?3) with six replicates. No significant differences were found between all formulated diets in terms of final weight, survival and feed conversion ratio. The commercial cottonseed variety displayed a significantly lower feed efficiency ratio and protein efficiency ratio than one of the ULGCS diets. These results suggest that GCSM and/or transgenic ULGCS meals can be used to replace fishmeal in commercial shrimp diets.  相似文献   
72.
Prawns, "Macrobrachium rosenbergii," and crawfish, "Procambarus clarkii," were alternatively grown in ponds to determine if they were compatible and if total production could be increased. Brood crawfish were stocked into replicated ponds at rates of 0,60, 120 or 180 kg/ha on 18 April. Water was removed to encourage burrowing. Following this, rice was planted as forage. Post-larval prawns (0.02 g) were stocked 3 July in all ponds at 17,500/ha. Prawns in half the ponds were fed and those in the other ponds were not. Ponds were drained from 7 to 11 October. Prawn production ranged from 157 to 248 kg/ha; survival ranged from 69% to 88%, and average size ranged from 11 to 7 g. There was no significant difference (P > 0.05) between fed and non-fed treatments. The ponds were reflooded and crawfish were harvested by trapping from 15 January to 15 May. The average yield of crawfish ranged from 746 to 1,266 kg/ha. Stocking rate had no effect of crawfish yields (P > 0.25). Total yield, with prawns and crawfish combined, ranged from 1,037 to 1,237 kg/ha. Overall, prawns and crawfish were compatible in rotation. Prawns were a good size for soft shell production during months when crawfish are not available for soft shell production.  相似文献   
73.
为了研究游离棉酚对育雏期海赛克斯蛋仔鸡免疫功能的影响,本试验选用360只1日龄海赛克斯蛋雏鸡,随机分为4组,每组3个重复,每个重复30羽。Ⅰ组饲喂基础日粮,Ⅱ、Ⅲ、Ⅳ组为试验组,分别饲喂含游离棉酚70、105、140 mg/kg的日粮,进行为期42 d的饲养试验,分别在14、28、42日龄进行取样,测定免疫器官指数和血清中IL-2、IFN-γ的含量,并每周测定血清中新城疫HI抗体效价。结果显示,①日粮中不同水平的游离棉酚对雏鸡的胸腺、法氏囊、脾脏指数无明显影响;②日粮中不同水平的游离棉酚对新城疫抗体的产生无显著抑制作用(P>0.05);③日粮中不同水平的游离棉酚能明显降低鸡血清中IL-2、IFN-γ的含量。结果表明,当游离棉酚含量高达140 mg/kg时,对雏鸡的免疫器官指数及抗体的产生没有显著影响(P>0.05),但在第42日龄时能显著或极显著降低鸡血清中细胞因子的含量(P<0.05或P<0.01))。  相似文献   
74.
刘志勤  彭博 《安徽农业科学》2011,39(35):21753-21754,21837
[目的]优化棉籽粕微生物脱毒条件,降低棉籽粕中的游离棉酚含量。[方法]利用米曲霉3042固态发酵降解棉籽粕中的游离棉酚,通过单因素试验和正交试验,研究接菌量、发酵温度、料水比和发酵时间对棉籽粕脱毒的影响,确定棉籽粕微生物脱毒的最优脱毒条件。[结果]极差分析表明,影响发酵棉籽粕游离棉酚含量的4个因素主次顺序依次为料水比〉发酵温度〉接菌量〉发酵时间。正交试验表明,棉籽粕微生物最优脱毒条件为:米曲霉3042接菌量5%,发酵底物添加0.5%尿素和1%蔗糖,料水比1∶0.83,5℃发酵48 h。在此条件下,游离棉酚含量降至117 mg/kg,降解率达到78.13%,发酵棉籽粕粗蛋白含量达到40.16%,较发酵前提高了12.87%。[结论]该研究为生产能够达到饲用标准的棉籽粕饲料提供了科学依据。  相似文献   
75.
本试验旨在研究醋酸棉酚对异育银鲫生长性能、血清生化指标和棉酚残留的影响.选取平均体重为(31.68±0.01)g的异育银鲫270尾,随机分为3组(每组3个重复,每个重复30尾),分别饲喂在基础饲料中添加0(对照组)、300和900mg/kg醋酸棉酚的试验饲料.试验期为8周.结果表明:随着醋酸棉酚添加量的增加,畀育银鲫的...  相似文献   
76.
The objective was to evaluate the toxicity effect of gossypol on ultrastructure of mouse testis and the expression of Bax mRNA and Bcl-2 mRNA of sperm cells in mice.Forty-eight male mice were randomly divided into four groups:control group,L-group(30 mg·kg~(-1)·d),M-group(60 mg·kg~(-1)·d)and H-group(120 mg·kg~(-1)·d)and were orally administrated with gossypol diluted by sodium carboxymethyl cellulose(SCC)or SCC(control group)for 20 days.On the 21st day,all the mice were killed and ultrastructure changes of testis were observed by TEM.mRNA expression of Bax and Bcl-2 in testis was measured by semiquantitative RT-PCR.The results showed that the testicular ultrastructure in three treated groups was gradually damaged,according to the dosage of gossypol and cellular structure disordered and organelle degenerated,manifesting vacuolation of mitochondria,expansion of endoplasmic reticulum.mRNA expression of Bcl-2 in testis significantly increased(p0.05)in L-group and then significantly decreased(p0.05,p0.01)in M-group and H-group compared with that in the control group;mRNA expression of Bcl-2 in M-group and H-group significantly decreased(p0.05,p0.01)than that in L-group and Bcl-2 mRNA expression in H-group showed a significant decrease(p0.05)compared with that in M-group.On the other hand,mRNA expression of Bax significant increased(p0.05,p0.01)in M-group and H-group than that in the control group.The ratio of Bcl-2/Bax significantly reduced(p0.05,p0.01)in the treated group than that in the control group and was found to be an obvious dose-dependent.It demonstrated that the gossypol could induce the changes on ultrastructure of mice testis,down-regulate mRNA expression of Bcl-2 and up-regulate mRNA expression of Bax,which indicated that sperm cells were induced apoptosis.  相似文献   
77.
高效降解游离棉酚并改善棉籽粕营养品质的菌株筛选   总被引:1,自引:0,他引:1  
本试验旨在利用枯草芽孢杆菌和植物乳酸菌发酵棉籽粕,研究其对棉籽粕中游离棉酚降解率的影响,并对发酵前后棉籽粕的营养品质指标如活菌数、中性蛋白酶活性、酸溶蛋白质含量、pH、游离棉酚含量等进行比较。结果发现:可高效降解棉籽粕中游离棉酚的枯草芽孢杆菌菌株为BLCC1-0039,可有效改善发酵风味的植物乳酸菌菌株为BLCC2-0092。综合上述2株益生菌的优点,筛选出最优复配发酵方式为植物乳酸菌BLCC2-0092与枯草芽孢杆菌BLCC1-0039按照1∶1比例接种,37℃需氧发酵24h再厌氧发酵。与空白对照组相比,最优复配发酵组各发酵阶段发酵棉籽粕的pH显著降低(P0.05),厌氧发酵72h时pH降至5.27;酸溶蛋白质含量显著提高(P0.05),厌氧发酵72h时酸溶蛋白质含量达到23.54%;游离棉酚含量显著降低(P0.05),需氧发酵24h时游离棉酚降解率达到52.12%,厌氧发酵72h时游离棉酚降解率达到61.58%。由此可知,植物乳酸菌BLCC2-0092与枯草芽孢杆菌BLCC1-0039复配发酵可有效降低发酵棉籽粕中的游离棉酚含量并改善其营养品质。  相似文献   
78.
Gossypol, a polyphenolic aldehyde found in cottonseed, has been shown to perturb steroidogenesis in granulosa and luteal cells of rats, pigs and cattle. However, little is known about the direct effect of gossypol on theca cell functions in any species. The present study was conducted to investigate the effect of gossypol on the steroidogenesis and the expression of genes involved in it in cultured bovine theca cells. Theca cells were isolated from healthy preovulatory follicles and were cultured in the presence of luteinizing hormone (LH) for up to 7 days. During the culture period, main steroid products of the theca cells shifted from androstenedione (A4) at day 1 to progesterone (P4) from day 2 onward. At days 1 and 7, theca cells were treated with gossypol (0‐25 μg/mL) for 24 h. Gossypol inhibited LH‐stimulated theca cell A4 and P4 production in a dose‐dependent manner at both occasions. The viability of theca cells was not affected by gossypol at any doses used. Gossypol down‐regulated expressions of steroidogenic enzymes CYP11A1, HSD3B1 and CYP17A1, but not that of LHR. These results indicate that gossypol inhibits thecal steroidogenesis through down‐regulating gene expressions of steroidogenic enzymes but without affecting cell viability in cattle.  相似文献   
79.
This study was conducted to compare the effects of electron beam (EB) and gamma ray (GR) irradiation treatments at doses of 10, 20 and 30 kGy on chemical composition, protein quality and protein digestibility of cottonseed meal (CSM). GR irradiation in all doses significantly decreased the crude fiber of samples compared to raw CSM. Free and total gossypol content of CSM was decreased significantly by utilizing both types of irradiation in a dose‐dependent manner. Also, EB irradiation caused decrease in free and total gossypol content more than that of GR irradiation. GR irradiation at doses of 20 and 30 kGy, and EB irradiation at doses of 10, 20 and 30 kGy can significantly decrease protein solubility of CSM compared to that of a raw sample. GR irradiation at a dose of 30 kGy significantly increased apparent digestibility of protein compared to raw and EB irradiation of CSM at a dose of 10 kGy in Leghorn cockerels. Maximum increase in protein digestibility of CSM was observed in GR irradiation at a dose of 30 kGy. In conclusion, the present study showed that EB and GR irradiation reduced gossypol and crude fiber and increased protein digestibility of CSM but had no effect on protein quality of CSM.  相似文献   
80.
选用43周龄海兰褐壳蛋鸡120羽,随机分成4组,每组3个重复,每个重复10羽鸡分别饲喂游离棉酚(FG)含量为0mg/kg、20mg/kg、70mg/kg、120mg/kg的试验日粮。试验结果表明:(1)日粮游离棉酚水平对产蛋率影响不显著(P>0.05),(2)日粮游离棉酚水平对蛋重影响不显著(P>0.05)。(3)当FG达到120mg/kg时,蛋鸡的日采食量比对照组显著降低(P<0.05),下降了1.4g;日粮中FG含量达到70mg/kg时蛋鸡的日采食量略有下降。  相似文献   
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