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121.
In early embryogenesis, the posteroventral foregut endoderm gives rise to the budding endodermal organs including the liver, ventral pancreas and gallbladder during early somitogenesis. Despite the detailed fate maps of the liver and pancreatic progenitors in the mouse foregut endoderm, the exact location of the gallbladder progenitors remains unclear. In this study, we performed a DiI fate-mapping analysis using whole-embryo cultures of mouse early somite-stage embryos. Here, we show that the majority of gallbladder progenitors in 9–11-somite-stage embryos are located in the lateral-most domain of the foregut endoderm at the first intersomite junction level along the anteroposterior axis. This definition of their location highlights a novel entry point to understanding of the molecular mechanisms of initial specification of the gallbladder.  相似文献   
122.
Choroid plexus tumor (CPT) is a primary intracranial neoplasm of the choroid plexus epithelium in the central nervous system. In the current World Health Organization classification, CPT is classified into two categories; choroid plexus papilloma (CPP) and carcinoma (CPC). In the present study, we investigated immunohistochemical expressions of N-cadherin, E-cadherin and β-catenin in 5 canine CPT cases (1 disseminated CPC, 2 CPCs and 2 CPPs). One CPP case was positive for N-cadherin and β-catenin, but negative for E-cadherin. The disseminated CPC case was positive for E-cadherin and β-catenin, but negative for N-cadherin. The other cases were positive for the three molecules examined. These results suggest that loss of the N-cadherin expression might associate with the spreading of CPC cells.  相似文献   
123.
A 2-month-old male Japanese Black calf was presented with a 30-day history of progressive ataxia. Antemortem examination using computed tomography (CT) revealed narrowing of the disc spaces due to destruction of intervertebral structures between the first and second thoracic vertebrae and between the second and third thoracic vertebrae. Osteolysis was evident as irregular hypoattenuating lesions within the opposing end plates of the first, second and third thoracic vertebrae. Pseudomonas aeruginosa was detected as the causative bacteria, and discospondylitis was diagnosed. To the best of our knowledge, this is the first bovine case report describing the application of CT for the diagnosis of discospondylitis.  相似文献   
124.
The aim of the present study was to examine changes in innate immune factors in the milk of mastitic dairy cows treated with antibiotics. Cows in the antibiotics group (n = 13) were infused into the mammary gland with cefazolin on the sixth day after mastitis was diagnosed (the day of the mastitis diagnosis = day ?6). The control group (n = 12) was not treated. Milk samples were collected once every 2 days from days ?6 to 12 and somatic cell count (SCC), lingual antimicrobial peptide (LAP), and lactoferrin (LF) concentrations and lactoperoxidase (LPO) activity were measured. SCC and LF concentrations in the antibiotics group markedly decreased after the antibiotic treatment. When cows in the antibiotics group were divided according to SCC on day 0, LAP concentrations and LPO activity in cows with a lower SCC on day 0 (<5 × 106 cell/mL) were significantly higher and lower than those in cows with a higher SCC, respectively. These results suggest that LF concentration decreased with decrease in SCC after treatment and that LAP concentration and LPO activity differed depending on the severity of mastitis. This is the first report to reveal the dynamics of innate immune factor in milk of cows treated for clinical mastitis.  相似文献   
125.
Clock mutation affects circadian regulation of circulating blood cells   总被引:1,自引:0,他引:1  

Background  

Although the number of circulating immune cells is subject to high-amplitude circadian rhythms, the underlying mechanisms are not fully understood.  相似文献   
126.
Within-field soil variability has often been reported in Japanese paddy fields. In one of such fields, we examined the relationships of spatial variations among different forms of soil nutrients and their direct influence on rice growth. Samples of surface soils collected from 100 plots (5 x 10 m) in the field were analyzed for the contents of N, P, and K as well as for the total C and clay contents. The values of the coefficient of variation (CV) for the soil properties were relatively high, ranging from 7% (total K) to 33% (inorganic N). More than 60% of the variation was spatially dependent, with ranges of less than 30 m for the contents of inorganic N and clay, 30-40 m for the contents of N (mineralizable and total), P (water-soluble, available, and total), and total C, and more than 60 m for the content of K (water-soluble, exchangeable, and nonexchangeable). These properties were grouped into two types; those significantly correlated either with the total C content (contents of mineralizable N, total N, all P forms, water-soluble K, exchangeable K, and 0.01 M HCl-extractable nonexchangeable K) or with the clay content (contents of fixed Nand NaBPh4-extractable nonexchangeable K). In a pot experiment in which rice plants were grown in soil from each plot for 50 d, the dry matter weight of shoots exhibited a large variation (CV 12%) and increased significantly with the increase of the level of the components related to the total C content, especially the content of mineralizable N. Significantly positive correlations were also found between the contents of N, P, and K in shoots and the corresponding soil nutrients occurring in a moderately labile form. These soil-plant relationships suggest that site-specific application of organic fertilizers for altering the level of the components related to the total C content in the topsoil could be effective to homogenize rice growth in the paddy field examined.  相似文献   
127.
The shallot is considered an important genetic resource for Allium breeding programs because, compared to the bulb onion, the shallot contains higher levels of several functional chemical compounds. However, there may be differences in content, composition and beneficial activity among shallot landraces. This study was carried out to characterize the differences in phenolic, quercetin, sugar, S-alk(en)yl-l-cystein sulfoxide (ACSO), and saponin contents and antioxidant capacities of a shallot germplasm including 31 strains derived from different regions of Vietnam and six other countries. A wide variation was observed in the quantitative analyses of the chemical contents. Shallots with high contents of polyphenols, saponins, and quercetins were found in the south of Vietnam and other low-latitude countries. Meanwhile, those possessing fairly high ACSO and sugar contents were observed in the north of Vietnam. Qualitative analysis of saponins via thin layer chromatography did not show clear variation among shallot strains, but polymorphism was observed between the shallot and other Allium species, such as A. roylei. The principal component analysis could clearly discriminate shallot strains by their geographical origins. All shallot strains showed potent antioxidant activities in a DPPH assay. The highest antioxidant capacity was in the strains possessing relatively high contents of polyphenol, quercetin, and saponin. Significant correlations were found between antioxidant capacity (IC 50 ?1 ) and four groups of chemical compounds (polyphenols, quercetins, saponins, and ACSOs) (r = 0.40–0.59). A strong correlation was observed between IC 50 ?1 and quercetin contents (r = 0.59, p < 0.01). The six Fusarium-inoculated shallot strains seemed to be adequately resistant against disease, and the levels of resistance may be related to the saponin content in the bulb tissues.  相似文献   
128.
129.
Iron (Fe) deficiency is a serious agricultural problem, especially in calcareous soils, which are distributed worldwide. Poplar trees are an important biomass plant, and overcoming Fe deficiency in poplars will increase biomass productivity worldwide. The poplar Fe-deficiency response and the genes involved in poplar Fe homeostasis remain largely unknown. To identify these genes and processes, we cultivated poplar plants under Fe-deficient conditions, both in calcareous soil and hydroponically, and analyzed their growth rates, leaf Soil and Plant Analyzer Development (SPAD) values, and metal concentrations. The data clearly showed that poplars have notable growth defects in both calcareous soil and a Fe-deficient hydroponic culture. They exhibited serious chlorosis of young leaves after 3 weeks of Fe-deficient hydroponic culture. The Fe concentrations in old leaves with high SPAD values were markedly lower in Fe-deficient poplars, suggesting that poplars may have good translocation capability from old to new leaves. The Zn concentration in new leaves increased in Fe-deficient poplars. The pH of the hydroponic solution decreased in the Fe-deficient culture compared to the Fe-sufficient culture. This finding shows that poplars may be able to adjust the pH of a culture solution to better take up Fe. We also analyzed the expression of Fe homeostasis-related genes in the roots and leaves of Fe-sufficient and Fe-deficient poplars. Our results demonstrate that PtIRT1, PtNAS2, PtFRO2, PtFRO5, and PtFIT were induced in Fe-deficient roots. PtYSL2 and PtNAS4 were induced in Fe-deficient leaves. PtYSL3 was induced in both Fe-deficient leaves and roots. These genes may be involved in the Fe uptake and/or translocation mechanisms in poplars under Fe-deficient conditions. Our results will increase a better understanding of the Fe-deficiency response of poplars and hence improve the breeding of Fe-deficiency-tolerant poplars for improved biomass production, the greening of high pH soils, and combatting global warming.  相似文献   
130.
Ecdysteroids are a class of steroid hormones in arthropods that control molting and metamorphosis through interaction with intracellular nuclear receptors. In contrast to the extensive literature describing their biosynthetic pathways and signaling components, little has been known about how these hormones are traveling into and out of the cells through lipid bilayers of the cell membranes. Recently, a series of studies conducted in the fruit fly Drosophila melanogaster revealed that membrane transporters have critical functions in trafficking ecdysteroids across cell membranes, challenging the classical simple diffusion model of steroid hormone transport. Here we summarize recent advances in our understanding of membrane transporters involved in ecdysteroid signaling in Drosophila, with particular focus on Ecdysone Importer (EcI) that is involved in ecdysteroid uptake in peripheral tissues. We then discuss the potential advantage of EcI blockers as a novel pest management tool as compared to classical insect growth regulators.  相似文献   
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