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51.
以我校教职工为全部受检对象,采集清晨空腹血样,通过对1 136例血浆中胆固醇(C)甘油三酯(TG)、高密度脂蛋白(HDL)水平进行检测,表明我校教职工从性别上看C、TG、HDL水平差异不显著,以45岁为界值,年龄在45岁以上各年龄组与年龄在45岁以下各年龄组相比差异极显著。结果表明:我校教职工血浆中胆固醇、甘油三酯随年龄的增长而递增,高密度脂蛋白的含量男性随年龄增长有所下降,而女性则随年龄的增长有所增加,这与正常人空腹血脂浓度受性别影响有关,但总体水平接近正常值,说明我校教职工饮食结构较为合理,身体比较健康。  相似文献   
52.
单核增生性李斯特杆菌感染和李氏溶血素   总被引:1,自引:0,他引:1  
单核增生性李斯特杆菌病能引起绵羊、人和其他很多动物疾病,在免疫学检测上有重要意义,在研究胞内菌感染的分子机制上也是一个重要的模型。但由于当前血清学试验上的非特异性和非敏感性,使李氏杆菌病的诊断和流行病学调查存在困难。在所有致病性的李斯特杆菌中,李斯特溶血素是主要致病因子,现已经有用其做诊断抗原的报道。文章论述了近年来单核增生性李斯特杆菌及李氏溶血素的最新进展,对研究李氏杆菌病的发病机理有一定作用。  相似文献   
53.
Two experiments (I and II) were conducted to evaluate the effect of nonprotein phenolic amino acid, L ‐dopa (L ‐3,4‐dihydroxyphenylalanine) on growth, metabolism and feed assimilation of common carp. Six isonitrogenous and isoenergetic diets (diets 1–6 containing 0, 2.5, 7.0, 14, 28 and 56 g kg–1L ‐dopa, respectively) were prepared by replacing wheat meal in the feed with L ‐dopa. For experiment I (8‐week duration), each treatment had two replicates with five fish each per replicate (mean initial body mass of 13.4 ± 1.0 g), whereas five groups of carp, each consisting of three fish, individually kept in respiration chambers, giving three replicates per treatment with a mean body mass of 25.0 ± 1.8 g were used for experiment II (4‐week duration). Fish were fed six times their maintenance ration daily (3.2 g feed kg–0.8 day–1). No fish died during either experiment. In experiment I, the growth rate, feed conversion ratio (FCR), protein efficiency ratio (PER) and apparent net protein utilization (ANPU) of carp fed diets 1, 2 and 3 were similar but they were significantly (P < 0.05) higher than those in dietary groups 4, 5 and 6. However, no significant differences were observed with regard to body composition (moisture, protein, lipid, ash and energy contents) between control (1) and the diets 2, 3, 4 and 5. Fish fed diet 6 had reduced lipid and energy contents (P < 0.05) when compared with other dietary groups. In experiment II, L ‐dopa significantly increased the oxygen consumption per unit body weight gain in treatments 4, 5 and 6. The average metabolic rate also tended to be higher in these groups. The energy expenditure was similar in treatment groups, but the energy retention was significantly lower and energy dissipated significantly higher in dietary groups 4, 5 and 6. The cholesterol level in blood plasma between the control and L ‐dopa containing diets was not significantly different. It may be concluded that at higher inclusion rates (>7 g kg–1) L ‐dopa appears to be a major antinutrient and hence the protein sources of plant origin, containing high amounts of L ‐dopa (i.e. mucuna beans) should be used with caution as fish meal substitutes in carp diets.  相似文献   
54.
采用SDS-PAGE研究成都麻羊乳上皮黏蛋白MUC1的遗传多态性,并以金堂黑山羊、乐至黑山羊、自贡黑山羊、藏山羊作对照进行比较分析。结果表明:成都麻羊与对照山羊乳MUC1的多态性丰富,成都麻羊有7种基因型、5个等位基因优势基因为C、D、E,金堂黑山羊7种基因型、6个等位基因优势基因为B、C、D,乐至黑山羊6种基因型、6个等位基因优势基因为B、C、D,自贡黑山羊5种基因型、5个等位基因优势基因为A、C、D,藏山羊3种基因型、3个等位基因优势基因为C、D。乳MUC1的基因型、等位基因的分布品种间有差异;根据乳MUC1等位基因频率对供试山羊品种进行聚类分析,成都麻羊与金堂黑山羊的遗传距离最小(D=0.2507)先聚为一类,再依次与乐至黑山羊(D=0.2831)、自贡黑山羊(D=0.3721)、藏山羊(D=0.4752)聚为一大类,结果较好的反映了成都麻羊与对照山羊品种间的亲缘关系。  相似文献   
55.
This study investigated the effects of Moringa oleifera (MO) as a partial substitute of alfalfa hay on milk yield, nutrient apparent digestibility and serum biochemical indexes of dairy cows. MO was harvested at 120 days post‐seeding. Fresh MO was cut, mixed with chopped oat hay (425:575 on a DM basis), ensiled and stored for 60 days. Sixty healthy Holstein dairy cows were allocated to one of three groups: NM (no MO or control), LM (low MO; 25% alfalfa hay and 50% maize silage were replaced by MO silage) or HM (high MO; 50% alfalfa hay and 100% maize silage were replaced by MO silage). The feeding trial lasted 35 days. The LM and HM diets did not affect dry matter (DM) intake, milk yield or milk composition (lactose, milk fat, milk protein and somatic cell count). The apparent digestibility of DM and NDF was lower for HM group than NM group. Additionally, there were no significant differences in serum biochemical indexes between the LM and NM groups. The HM group had lower serum concentrations of total cholesterol, high‐density lipoprotein cholesterol, and low‐density lipoprotein cholesterol and higher serum concentrations of urea than the NM group. The partial replacement of alfalfa hay (≤50%) and maize silage with MO silage had no negative effects on milk yield, in vivo nutrient apparent digestibility or serum biochemical indexes of lactating cows.  相似文献   
56.
胆固醇的代谢,即胆固醇的合成和转化过程,尤其是胆固醇和胆汁酸之间的相互转化是胆固醇降解的主要通路。胆固醇的代谢和调控紊乱,以及高胆固醇血症所引起的如动脉粥样硬化等心血管疾病的研究越来越多,同时治疗这种高胆固醇血症相关疾病的药物也相继发现。论文通过对胆固醇的代谢途径、调控机制、高胆固醇疾病及其治疗药物进行综述,对胆固醇的来源、去路以及该代谢过程中的调控机制进行较为全面的探讨,为与胆固醇相关疾病及其治疗研究提供依据。  相似文献   
57.
A total of 540 2‐day‐old male Ross 308 broilers were used in a 35‐day experiment and were randomly divided into five treatments: (i) NC (low energy); (ii) PC (high energy diet); (iii) P1 (NC + 0.1% carbohydrases); (iv) P2 (NC + 0.05% emulsifier); and (v) P3 (NC + 0.1% carbohydrases + 0.05% emulsifier). From days 0 to 21, body weight gain in PC and P3 treatments increased (P < 0.05) compared with NC treatment. The chicks fed PC, P1, P2 and P3 improved (P < 0.05) feed conversion ratio compared with the NC treatment throughout the whole experiment. Abdominal fat weight was heavier (P < 0.05) in PC, P2 and P3 treatments than in NC and P1 treatments. On day 35, serum total cholesterol and low density lipoprotein cholesterol concentration were higher (P < 0.05) and high‐density lipoprotein cholesterol was lower (P < 0.05) in NC and P2 treatments than in PC, P1 and P3 treatments. The concentration of oleic acid, linoleic acid and total unsaturated fatty acids were highest (P < 0.05) in PC than in the other treatments. In conclusion, the results indicate that low energy density diet had lower growth performance, while the inclusion of emulsifier and carbohydrases in low energy diets can partially improve growth performance.  相似文献   
58.
对零世代8周龄血浆极低密度脂蛋白(VLDL)浓度进行降低腹脂的间接选择,一世代取得了明显效果:腹脂和肝脂向两极分化,其中肌胃脂和肝脂选择反应较大。低血浆VLDL的选择使腹脂降低,肝脂增加,对产肉性状未产生不利影响。9周龄腹脂率、板油率和肌胃脂率在高VLDL系分别高于低VLDL系21%,16%和51%;肌胃脂率品系间差异极显著(P<0.001)。品系与性别互作对肌胃脂率有明显影响(P<0.05)。腹脂、肌胃脂存在性别差异,腹脂率雌性略高于雄性,而肌胃脂率雄性高于雌性。9周龄肝脂率,高VLDL系显著低于低VLDL系(P<0.01),雌性高于雄性。一世代8周龄血浆VLDL产生了直接选择反应,血浆VLDL浓度,高VLDL系高于低VLDL系。血浆VLDL存在性别差异,雄性高于雌性。一世代高、低VLDL系血浆VLDL和腹脂的变异系数仍然很大,继续对其选择仍然有效。由于血浆VLDL属中等遗传力,并且家系间差异显著,因此,在世代选育中应采取家系结合个体选择法  相似文献   
59.
磷对奶牛红细胞膜脂质的影响   总被引:5,自引:0,他引:5  
对15例临床上有明显低磷血症的奶牛血清磷、红细胞膜脂质成分进行了测定。结果表明,低磷血症奶牛血清磷、红细胞膜磷脂明显降低;红细胞膜胆固醇及膜胆固醇/磷脂摩尔比值(nch/npl)明显升高,与健康对照组牛相比差异极显著(P<0.01);直线相关分析表明,血清磷与红细胞膜磷脂之间呈极显著正相关(r=0.917,y=10.852x+3.196,P<0.01);与红细胞膜胆固醇以及nch/npl之间分别呈显著负相关(r=-0.940,y=2.850x-1.072,P<0.01;r=-0.920,y=1.968x-1.401,P<0.01)。此外,红细胞膜微粘度与膜磷脂之间呈显著负相关(r=-0.954,y=19.122x-4.384,P<0.01),而与膜胆固醇以及nch/npl之间呈显著正相关(r=0.988,y=0.927x+0.964,P<0.01;r=0.978,y=-0.293x+1.113,P<0.01)。结果表明,磷是红细胞膜脂质成分改变的先决因素,而后者又是红细胞膜流动性及膜结构、功能发生变化并导致膜损伤的一个重要因素。  相似文献   
60.
The nature of the hyperlipemia in two 3-week-old male kittens, one of which was presented with the owner's complaints of retarded growth and white streaks on its eyes, was studied. Hypertriglyceridemia, hypercholesterolemia, and reduced Post-Heparin Plasma Lipolytic Activities (PHPLA) were observed in both animals. One of the kittens, however, was more severely affected and in addition, had lipemia retinalis and a marked lactescent, hyperchylomicronemic serum in spite of a short-term fast before sampling. These findings are strikingly similar to those found in human Type I hyperlipoproteinemia due to familial Lipoprotein Lipase (LPL) deficiency. Diagnosis of persistent hyperlipemic syndromes in kittens should include the possibility of LPL deficiency as determined by PHPLA measurements.  相似文献   
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