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81.
Mutations in proteins of the Drosophila phototransduction cascade, a prototypic guanine nucleotide-binding protein-coupled receptor signaling system, lead to retinal degeneration and have been used as models to understand human degenerative disorders. Here, modulating the sphingolipid biosynthetic pathway rescued retinal degeneration in Drosophila mutants. Targeted expression of Drosophila neutral ceramidase rescued retinal degeneration in arrestin and phospholipase C mutants. Decreasing flux through the de novo sphingolipid biosynthetic pathway also suppressed degeneration in these mutants. Both genetic backgrounds modulated the endocytic machinery because they suppressed defects in a dynamin mutant. Suppression of degeneration in arrestin mutant flies expressing ceramidase correlated with a decrease in ceramide levels. Thus, enzymes of sphingolipid metabolism may be suitable targets in the therapeutic management of retinal degeneration.  相似文献   
82.
Tropical Animal Health and Production - Early selection of ewes for better reproductive performance may reduce generation interval and increase genetic gains. Considering this, the present study...  相似文献   
83.
BACKGROUND: There is limited published information regarding feline multiple myeloma. Diagnostic criteria are derived from canine studies and to our knowledge, have not been critically reviewed for cats. OBJECTIVE: To evaluate the clinical and laboratory findings in cats with multiple myeloma and appraise diagnostic criteria. METHODS: Retrospective evaluation of medical records was performed. Inclusion required an antemortem diagnosis of multiple myeloma using 2 of 4 criteria: 1) >or=20% plasma cells in the bone marrow, or >or=10% if atypical plasma cells; 2) paraproteinemia; 3) radiographically-evident osteolysis; 4) light chain proteinuria. Alternatively, a postmortem diagnosis was based on the findings of multiple plasma cell neoplasms, with marrow involvement. RESULTS: Sixteen cats were diagnosed with multiple myeloma between 1996 and 2004, with a median age of 14.0 years; 9 of 16 (56%) were castrated males, and 7 of 16 (44%) were spayed females. Laboratory abnormalities included hyperglobulinemia (14/16, 87.5%), with 11/14 (78.5%) monoclonal and 3/14 (21.4%) biclonal gammopathies; hypoalbuminemia (4/16, 25%); light chain proteinuria, (4/9, 44.4%); hypocholesterolemia (11/16, 68.7%); hypercalcemia, (3/15, 20%); nonregenerative anemia, (11/16, 68.7%); regenerative anemia, (1/16, 6.2%); neutropenia (5/15, 33.3%); thrombocytopenia (8/16, 50%); and marrow plasmacytosis (14/15, 93.3%). Plasma cells were markedly immature, atypical, or both in 10 of 12 (83.3%) cats. Focal or multifocal osteolysis was noted in 6 of 12 (50%) cats for which radiographs were available for review; generalized osteopenia was found in 1 (8.3%) cat. Noncutaneous, extramedullary tumors were found in all cats assessed, 7/7 (100%), including spleen (6), liver (3), and lymph nodes (4). The disease in 1 of 2 cats with cutaneous tumors progressed to plasmacytic leukemia. CONCLUSIONS: Common findings in feline multiple myeloma include atypical plasma cell morphology, hypocholesterolemia, anemia, bone lesions, and multi-organ involvement. Based on the results of this study, we advocate modifying diagnostic criteria in cats to include consideration of plasma cell morphology and visceral organ infiltration.  相似文献   
84.
85.
Pioneer Venus orbiter dual-frequency radio occultation measurements have produced many electron density profiles of the nightside ionosphere of Venus. Thirty-six of these profiles, measured at solar zenith angles (chi) from 90.60 degrees to 163.5 degrees , are discussed here. In the "deep" nightside ionosphere (chi > 110 degrees ), the structure and magnitude of the ionization peak are highly variable; the mean peak electron density is 16,700 +/- 7,200 (standard deviation) per cubic centimeter. In contrast, the altitude of the peak remains fairly constant with a mean of 142.2 +/- 4.1 kilometers, virtually identical to the altitude of the main peak of the dayside terminator ionosphere. The variations in the peak ionization are not directly related to contemporal variations in the solar wind speed. It is shown that electron density distributions similar to those observed in both magnitude and structure can be produced by the precipitation on the nightside of Venus of electron fluxes of about 108 per square centimeter per second with energies less than 100 electron volts. This mechanism could very likely be responsible for the maintenance of the persistent nightside ionosphere of Venus, although transport processes may also be important.  相似文献   
86.
87.
Genetic Resources and Crop Evolution - Genetic diversity analysis contributes to the conservation, protection and utilization of genetic resources toward efficient management of germplasm. In this...  相似文献   
88.
Differences in the degree of starch granule swelling and granule morphology are shown as a function of iodine concentration during heating. The observations reveal a restriction and delay in wheat and corn starch swelling in presence of iodine (0.02%) and a lack of swelling at higher iodine concentration (0.2%). The presence of iodine during heating did not influence waxy corn starch granule swelling, even at the higher concentration. A delay in the increase in paste viscosity during heating was observed, and gel formation was precluded after cooling at the higher iodine concentration. Waxy corn starch pastes formed a weak gel even at the higher iodine concentration. Spectrophotometric analyses showed that polymers leach into the solution when heated in the presence of 0.02% iodine, while no leaching was observed at 0.2% iodine concentration. Furthermore, the length and the amount of polymers leaching from normal corn were different from that observed for wheat starch. Thermal analyses reveal a shift in the onset of gelatinization temperature and an increase in the enthalpy in the amylose‐lipid region of the endotherm. While the iodine‐polymer complex did not appear to exhibit an endotherm during heating, the granules exhibited a diffused polarized cross, suggesting the presence of an ordered complex.  相似文献   
89.
Cranberry ( Vaccinium macrocarpon ) has been shown in clinical studies to reduce infections caused by Escherichia coli and other bacteria, and proanthocyanidins are believed to play a role. The ability of cranberry to inhibit the growth of opportunistic human fungal pathogens that cause oral, skin, respiratory, and systemic infections has not been well-studied. Fractions from whole cranberry fruit were screened for inhibition of five Candida species and Cryptococcus neoformans , a causative agent of fungal meningitis. Candida glabrata , Candida lusitaniae , Candida krusei , and Cryptococcus neoformans showed significant susceptibility to treatment with cranberry proanthocyanidin fractions in a broth microdilution assay, with minimum inhibitory concentrations as low as 1 μg/mL. MALDI-TOF MS analysis of subfractions detected epicatechin oligomers of up to 12 degrees of polymerization. Those containing larger oligomers caused the strongest inhibition. This study suggests that cranberry has potential as an antifungal agent.  相似文献   
90.
Phytates represent a significant pool of organic phosphorus (Po) that is largely unavailable to plants. This study deals with phytate-mineralizing (PM), organic-acid-producing (OAP) rhizobacterial isolates, their characterization and their effect on plant growth. Their genetic diversity was assessed by 16S rRNA amplified ribosomal DNA restriction analysis (ARDRA) and selected isolates were identified by partial sequencing of 16S rRNA gene. Na-phytate and Po rich poultry farm manure (PFM) used as sources of phosphorus in semi-solid-agar (SSA) medium and soil respectively, for plant inoculation studies, where Cajanus cajan (pigeon pea) used as plant. Of thirty-nine rhizobacterial isolates, nineteen were proficient at releasing phosphate (Pi) (up to 85 μg/ml) from sparingly soluble calcium (Ca)-phytate and concomitantly decreasing the pH of minimal medium with 100 mM glucose from 8.0 to below 5. When the medium contained glycerol in place of glucose, Ca-phytate remained undissolved with no significant Pi released and no decline in pH. Genetic diversity of phytate-mineralizing (PM) rhizobacterial isolates suggests that the isolates mainly fall in two populations: acid-producing (AP) population (mainly represented by members of Enterobacteriaceae) and non-AP population. OAP-PM rhizobacterial isolates were identified as Citrobacter, Pantoea, Klebsiella and Enterobacter species. Organic acids (OAs) secreted by PM isolates were detected by HPLC, showed secretion of gluconic and acetic acids. Importance of OAs in Ca-phytate dephosphorylation was demonstrated in vitro using A. ficuum phytase. Gluconate and acetate additions enhanced phytase catalyzed dephosphorylation of Ca-phytate in vitro. Sonicated cell lysates of isolates showed significant Pi release from Ca-phytate compared to whole cells, indicating inaccessibility of Ca-phytate due to poor solubility. Selected isolates showed that they possess cell-associated acid phytase and modulators of phytase activity suggested that the enzymes are histidine acid phosphatase (HAP) type of phytase. OAP-PM isolates PP1 and DHRSS showed significant increase in dry shoot/root ratio and P content of shoot in Na-phytate containing semi-solid agar (SSA) medium, but isolate DHRSS did not increase dry shoot/root ratio in soil experiments containing poultry farm manure as source of P, although it significantly increased shoot P content of plants. The inoculation of isolates enhanced the shoot P content and dry shoot/root ratio, but did not increase the dry weight in SSA medium. It may be concluded that some OAP-PM rhizobacterial isolates that release P from Ca-phytate show increase in shoot P content in phytate containing SSA medium and in soils.  相似文献   
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