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431.
The genome of Malassezia pachydermatis isolates from dogs was resolved into six chromosomes by using pulsed-field gel electrophoresis and their molecular sizes were calculated as 820, 1,100, 1,400, 1,470, 1,660 and 1,820 Kb, respectively. Comparison of electrophoretic patterns suggested that the chromosomes of M. pachydermatis were homozygous.  相似文献   
432.
In order to detect the presence of aflatoxin B1 (AFB1), the use of the enzyme-linked immunosorbent assay (ELISA) and recovery test was evaluated. The detection limit of ELISA for AFB1 was 1 pg/assay and the recovery from maize spiked with AFB1 exceeded 80%. AFB1 was detected by ELISA in seven out of twelve samples of imported food products including peanut, almond, red pepper, cocoa bean, black pepper, buckwheat, walnut, adlay, soybean, popcorn, and pistachio nut, and by high performance liquid chromatography (HPLC) in four of the samples. However, the content of AFB1 in these samples was less than 10 ng/g of the minimum value authorized by the Japanese sanitation law. These results demonstrate that ELISA is more sensitive than HPLC and imported food products are broadly contaminated with AFB1.  相似文献   
433.
Cabbage (B. oleracea L. var. capitata L.) plants wore grown for 79 days in cuture solutions obtaining 4 levels of lithium, 0, 0.1, 1. 10 mel) sodium (0, 0.2. 2, 20, or rubidium , 0, 0.05, 0.5) combined with a low or high supply of potassium(0.2 or 2 mcf/l, and the effects of the cations supplied on the growth and ration composition of the plants were studied.

The total dry weight of the plants decreased at higher levels of the cations, especially Li in the culture solution, concurrent with an increaie in the contents of each cation in the plants. The decrease in the dry weight at higher levels was smaller in the high K supply, than in the low supply, causing a decrease in the contents of the cations. The critical contents of Li, Na, and which resulted in a 50° decrease in the dry weight or inner leaves due to excess injury were estimated to be about 0.07, 2.5, and 3.0% on a dry basis in the outer leaves and 0.05, 2.0, and 3.0% in the roots, respectively, regardless of the K supply.  相似文献   
434.
One of the major difference between the in vivo and in vitro embryonic environments is the stiffness of the culture substrate. Xanthan gum (XG) and locust bean gum (LBG) are natural materials that are safe, inexpensive and easy to handle. In this study, we investigated the effects of using a polysaccharide culture substrate made from 1% XG and 1% LBG (XG-LBG gel) on bovine embryonic development. Oocytes collected from bovine ovaries were subjected to maturation, and fertilization to generate embryos at an early developmental stage (>4 cell stage). Cleaved embryos were further cultured in a well of 96-well cell culture plate coated with or without XG-LBG gel for 5 days. While the developmental rate up to the blastocyst stage did not differ between the two culture systems (control, 38.0 vs. gel, 38.6%), blastocysts developed on the XG-LBG gel produced significantly high cell numbers and ATP content. Embryos cultured on XG-LBG gels for 24 hr had high expression levels of F-actin and a highly even distribution of E-cadherin. In addition, embryos developed on XG-LBG gel demonstrated increased translocation of YAP to the nucleus and increased connective tissue growth factor (CTGF) protein levels (downstream of Hippo signalling). These findings suggest that soft culture substrates improve embryonic development by enhancing mechanotransduction, including YAP-CTGF signalling.  相似文献   
435.
Recessive missense mutation in the solute carrier family 12, member 1 (SLC12A1) gene (g.62382825G>A) is associated with hydrallantois, which is the accumulation of fluid in the allantoic cavity of a pregnant animal, and usually causes fetal death in Japanese Black cattle. However, the symptoms of a homozygote with this mutation that do not result in fetal death have not previously been tracked and evaluated. In the present study, we observed a homozygote with the SLC12A1 risk allele over a long‐term period. The calf did not show any obvious clinical symptoms, although it did exhibit a slight growth retardation that accompanied mild calciuria. At 28 months of age, the homozygote showed renal dysfunction, which in turn resulted in hydronephrosis. The time course of the symptoms was consistent with the phenotype of Bartter syndrome in humans. Additionally, the risk heterozygous genotype did not any effects on carcass traits, which indicates that eliminating the risk allele would not have any unfavorable effects. Therefore, we emphasize that both the fetal‐ and late‐stage symptoms associated with the SLC12A1 risk allele compromise animal welfare, and consequently may result in severe economic losses for individual farmers if the SLC12A1 risk allele is not eliminated from the population.  相似文献   
436.
Female moths of different species but belonging to the same subfamily produce an identical compound as their sex pheromone. The sex pheromone of the almond moth, Cadra cautella (Walker), and the Indian meal moth, Plodia interpunctella (Hübner), has been isolated and identified as cis-9, trans-12-tetradecadienyl acetate.  相似文献   
437.
Three forms of female-specific plasma protein were purified from blood plasma of estrogen-treated white perch, characterized, and classified as three distinct vitellogenins (VgA, VgB, and VgC). This study describes the first purification of three classes of native Vg from any vertebrate and sets the stage for discovery of the different functions of each type of Vg.  相似文献   
438.
This study dealt with the detection of parentage in a mixed family tank of abalone Haliotis discus hannai using microsatellite DNA markers. As a preliminary investigation, the early growth rate between selected and non-selected abalone families, which were reared together in the mixed family tank from settlement stage to juvenile stage (7 months of age), was also compared. The selected families were derived from seven parents (three females and four males) selected for larger size in shell length at about 1-year-old, and the non-selected families originated from five wild captives (three females and two males). Parentage analysis based on eight microsatellite markers unambiguously allocated the 170 juveniles sampled from the single tank to the 17 parental pairs. The family size was highly heterogeneous among families, as two males in the selected families and one male in the non-selected families dominated the contribution to the offspring pool (>80%). The mean shell length of the selected families was approximately 23% larger than that of the non-selected families (Student’s t-test, P<0.001). This study demonstrated that the use of microsatellite markers is effective for parentage determination in the mixed family farming, commonly used in abalone hatcheries, and selective operations for larger size could improve the growth of the next generation.  相似文献   
439.
Changes in serum thyroxine (T4), estradiol-17β (E2) and testosterone (T) levels during the parr-smolt transformation (smoltification) were investigated in the masu salmon (Oncorhynchus masou) in 1985 and 1987. T4 showed a peak in levels at the early stage of smoltification and E2 and T levels peaked almost at the same time. There were no significant differences between the concentrations of serum hormones in female and males. During smoltification, germ cells in the peri-nucleolus and spermatogonia stage were present in the ovary and testis, respectively. These results suggest that E2 and T may be involved in smoltification in the masu salmon.  相似文献   
440.
Sweetpotato (Ipomoea batatas L.) is an outcrossing hexaploid species with a large number of chromosomes (2n = 6x = 90). Although sweetpotato is one of the world’s most important crops, genetic analysis of the species has been hindered by its genetic complexity combined with the lack of a whole genome sequence. In the present study, we constructed a genetic linkage map based on retrotransposon insertion polymorphisms using a mapping population derived from a cross between ‘Purple Sweet Lord’ (PSL) and ‘90IDN-47’ cultivars. High-throughput sequencing and subsequent data analyses identified many Rtsp-1 retrotransposon insertion sites, and their allele dosages (simplex, duplex, triplex, or double-simplex) were determined based on segregation ratios in the mapping population. Using a pseudo-testcross strategy, 43 and 47 linkage groups were generated for PSL and 90IDN-47, respectively. Interestingly, most of these insertions (~90%) were present in a simplex manner, indicating their utility for linkage map construction in polyploid species. Additionally, our approach led to savings of time and labor for genotyping. Although the number of markers herein was insufficient for map-based cloning, our trial analysis exhibited the utility of retrotransposon-based markers for linkage map construction in sweetpotato.  相似文献   
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