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51.
Tetrodotoxin (TTX) is a crystalline, weakly basic, colorless organic substance and is one of the most potent marine toxins known. Although TTX was first isolated from pufferfish, it has been found in numerous other marine organisms and a few terrestrial species. Moreover, tetrodotoxication is still an important health problem today, as TTX has no known antidote. TTX poisonings were most commonly reported from Japan, Thailand, and China, but today the risk of TTX poisoning is spreading around the world. Recent studies have shown that TTX-containing fish are being found in other regions of the Pacific and in the Indian Ocean, as well as the Mediterranean Sea. This review aims to summarize pertinent information available to date on the structure, origin, distribution, mechanism of action of TTX and analytical methods used for the detection of TTX, as well as on TTX-containing organisms, symptoms of TTX poisoning, and incidence worldwide.  相似文献   
52.
A field study was conducted to determine effects of seasonal deficit irrigation on plant cob, leaf, stem and total fresh yield, plant height and water use efficiency (WUE) of silage maize for a 2-year period in the semiarid region. In addition, the crop and pan coefficients k c and k p of silage maize were determined in full irrigation conditions. Irrigations were applied when approximately 50% of the usable soil moisture was consumed in the effective rooting depth at the full irrigation treatment. In deficit irrigation treatments, irrigations were applied at the rates of 80, 60, 40, 20 and 0% of full irrigation treatment on the same day. Irrigation water was applied by hose-drawn traveler with a line of sprinklers. Increasing water deficits resulted in a relatively lower cob, leaf, stem and total fresh yields. The linear relationship between evapotranspiration and total fresh yield were obtained. Similarly, WUE was the highest in full irrigation conditions and the lowest in continuous stress conditions. According to the averaged values of 2 years, yield response factor (k y) was 1.51 for silage maize. When combined values of 2 years, seasonal pan coefficient (k p) and seasonal crop coefficient (k c) were determined as 0.84 and as 1.01 for silage maize, respectively.  相似文献   
53.
The study and development of transformation technology with new selection schemes is important for various fundamental studies and for crop trait improvement via genetic engineering. Here we have shown that hygromycin resistance is an effective system for plum genetic transformation. Embryonic axes of mature seeds were co-cultivated with Agrobacterium strain LBA4404 containing the pC1381 plasmid carrying the hygromycin phosphotranferase gene (hpt) and β-glucuronidase (GUS) gene or with strain EHA105 containing the plasmid pC1301 carrying the same marker and reporter genes. The latter strain containing a pC2301 plasmid carrying the neomycin phosphotransferase gene (nptII) gene was used as a control. Infected explants were placed on shoot induction medium containing either 5 mg L−1 hygromycin or 75 mg L−1 kanamycin for selection. Green shoots developed from the explants under hygromycin pressure. These shoots showed continued and vigorous growth and development upon transfer onto fresh hygromycin medium. PCR using hpt sequence primers, and Southern blot analysis using a probe from the hpt gene, confirmed the presence of the transgenes and their stable integration in regenerated plants. Full transgenic plants were obtained in a greenhouse. Hygromycin selection was very effective and no escapes were observed. The study demonstrated that hygromycin resistance can be used as an effective selectable marker for plum transformation. The new system developed here is important and useful for multiple gene transformation in plum.  相似文献   
54.
The effects of three finishing systems on carcass composition and other characteristics of meat were studied in 15 young Eastern Anatolian Red bulls in Eastern Turkey. For 93?days, five bulls grazed pasture (P), five grazed the same pasture and were given concentrate supplementation (P + C), and five grazed the same pasture for 93?days, and then for an additional 40?days, they received concentrate in a barn (PF). Carcasses of the P bulls were lighter and leaner than those of the PF animals. Compared with the P carcasses, PF carcasses had a greater percentage of kidney, pelvic, and heart fat (P?相似文献   
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56.
Bone-related complications are among the highest concerning metabolic diseases in the modern world. Bone fragility and susceptibility to fracture increase with age and diseases like osteoporosis. Elevated adipogenesis in bone results in osteoporosis and loss of bone mass when coupled with lack of osteoblastogenesis. In this study the potential effect of Salicornia herbacea extract against osteoporotic conditions was evaluated. Adipogenesis inhibitory effect of S. herbacea has been evidenced by decreased lipid accumulation of differentiating cells and expression levels of crucial adipogenesis markers in 3T3-L1 pre-adipocytes. S. herbacea treatment reduced the lipid accumulation by 25% of the control. In addition, mRNA expression of peroxisome proliferator-activated receptor (PPAR)γ, CCAAT/enhancer-binding protein (C/EBP)α and sterol regulatory element binding protein (SREBP)1c were inhibited by the presence of S. herbacea. Bone formation enhancement effect of S. herbacea was also confirmed in MC3T3-E1 pre-osteoblasts. The presence of S. herbacea significantly elevated the alkaline phosphatase (ALP) activity by 120% at a concentration of 100 μg/mL in differentiating osteoblasts. S. herbacea also significantly increased the expression of osteoblastogenesis indicators, ALP, bone morphogenetic protein (BMP)-2, osteocalcin and collagen type I (collagen-I). In conclusion, S. herbacea possess potential to be utilized as a source of anti-osteoporotic agent that can inhibit adipogenesis while promoting osteoblastogenesis.  相似文献   
57.
58.
The aim of this study was to evaluate the stress response to long-term transportation and to analyze the effects of vitamin A + D + E and vitamin E + selenium administrations on oxidative stress induced by long-term transportation in Holstein dairy cows. Control group (n = 10) received 0.9% saline (placebo), Group I (n = 10) received vitamin A + D + E, and Group II (n = 10) received vitamin E + selenium. After the transport, adrenaline levels were high in all groups (P < 0.05). Noradrenaline level was low in Group I (P < 0.05) and tended to be low in Group II. Mean levels of serum cortisol decreased significantly in all groups (P < 0.05) when comparing pre-transport data with post-transport data. Glucose levels increased in Control group (P < 0.05) and in Groups I and II (P < 0.01). The malondialdehyde level significantly increased in the Control group (P < 0.05) after the transport and the levels were lower in Group I (P = 0.076) and Group II (P < 0.05) than in the Control group. As a result, vitamin E + selenium and vitamin A + D + E have been determined to prevent lipid peroxidation and oxidative stress, associated with long-term transportation stress in cattle.  相似文献   
59.
The water-use characteristics of sesame (Sesamum indicum L.) were studied in the field under furrow irrigation. Irrigation water quantities were based on pan evaporation (Epan) from a screened class-A pan. Treatments consisted of three irrigation intervals (I1: 7 days; I2: 14 days, I3: 21 days), and four pan coefficients (Kcp 1: 0.60; Kcp 2: 0.80, Kcp 3: 1.00 and Kcp 4: 1.20). Average irrigation values for each treatment varied from 467 to 857 mm in 2003 and 398 to 654 mm in 2004. The highest seasonal evapotranspiration was obtained from the I3Kcp 4 treatment in 2004 (1019 mm); the lowest value was observed in the I1Kcp 1 treatment in the same year (598.0 mm). Data collected in 2003 and 2004 showed that the amount of irrigation water applied significantly the affected seed yield. However, the effects of irrigation interval on yield were not significant. On average, the Kcp 3 treatment gave the highest seed yield (1.915 t ha−1), whereas Kcp 1 treatment gave the lowest (1.538 t ha−1). Seasonal yield response factors (ky) were 1.01 and 0.54 in 2003 and 2004, respectively. ET/Epan ratios for each treatment varied from 0.3 to 1.3 in 2003 and from 0.1 to 1.1 in 2004. In conclusion, the Kcp 3 plant-pan coefficient is recommended for sesame grown under field conditions in order to maximise yield.  相似文献   
60.
This study was carried out to determine the presence and distribution of tick-borne haemoprotozoan parasites (Theileria and Babesia) in apparently healthy cattle in the East Black Sea Region of Turkey. A total of 389 blood samples were collected from the animals of various ages in six provinces in the region. Prevalence of infection was determined by reverse line blot (RLB) assay. The hypervariable V4 region of the 18S ribosomal RNA (rRNA) gene was amplified with a set of primers for members of the genera Theileria and Babesia. Amplified PCR products were hybridized onto a membrane to which generic- and species-specific oligonucleotide probes were covalently linked. RLB hybridization identified infection in 16.19% of the samples. Blood smears were also examined microscopically for Theileria and/or Babesia spp. and 5.14% were positive. All samples shown to be positive by microscopy also tested positive with RLB assay. Two Theileria (T. annulata and T. buffeli/orientalis) and three Babesia (B. bigemina, B. major and Babesia sp.) species or genotypes were identified in the region. Babesia sp. genotype shared 99% similarity with the previously reported sequences of Babesia sp. Kashi 1, Babesia sp. Kashi 2 and Babesia sp. Kayseri 1. The most frequently found species was T. buffeli/orientalis, present in 11.56% of the samples. T. annulata was identified in five samples (1.28%). Babesia infections were less frequently detected: B. bigemina was found in three samples (0.77%), B. major in two samples (0.51%) and Babesia sp. in five samples (1.28%). A single animal infected with T. buffeli/orientalis was also infected with B. bigemina.  相似文献   
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