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101.
1. Records of maerl beds in Irish waters were compiled from the following sources: Admiralty Charts, published/unpublished ecological/geological accounts, and personal communications/observations. 2. Geographic and depth distributions of maerl records in Irish waters are discussed. Two main areas, Galway Bay–Connemara and South West Ireland, were identified as harbouring the highest concentrations of confirmed records, with maximum depth of confirmed records being approximately 25–30 m. 3. Deposits shown as ‘crl’ markings on older Admiralty Charts may refer to maerl and are situated at greater depths (to 95 m) and are further offshore than confirmed deposits (to 32 m), the latter being based on more recent observations. 4. Although the precise number of maerl beds in Irish waters cannot be assessed from the available records, the minimum number of larger beds (>1 km2), based on confirmed records only, is 35–40 beds located in 18 areas. In addition, along the south‐west coastline numerous smaller spatial aggregations (as small as 1–5 m2) occur. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
102.
Andrea R. Pluess Victoria L. Sork Brian Dolan Frank W. Davis Delphine Grivet Kurt Merg Jeanette Papp Peter E. Smouse 《Forest Ecology and Management》2009
Short distance pollen dispersal shapes the local genetic structure of plant populations and determines the opportunity for genetic drift and local selection. In this paper we focus on short distance dispersal (SDD) of pollen in a low-density stand of a savannah oak, Quercus lobata Née. Specifically, we are interested in the proportional contributions of pollen donors, the pollen dispersal kernel that describes local matings, the extent to which wind influences mating success, and the extent to which pollen sources vary within the large canopy of these trees. Using maximum likelihood paternity analysis, we assigned sires for 474 outcrossed progeny of five seed trees, representing 120 of 160 potential mating pairs within a 250 m radius of each focal tree (ca. 20 ha plots). We first established that the effective number of pollen donors for progeny with sires within the plot was about 10 individuals, with average weighted pollination distances of 114.1 m. We estimated 18.5% pollen immigration into the 20 ha plots. We next established that the SDD portion of the dispersal kernel is best described by the exponential power, inverse power, and Weibull functions, all that capture high local dispersal with steep decay. Two of these models suggest that long distance dispersal is abundant, represented by a fat tail, while the Weibull indicates depauperate long distance dispersal, represented by a thin tail. The addition of a directional component corresponding to the predominant wind axis had no meaningful impact on these models. Finally, we established that different parts of an individual tree canopy of Q. lobata sample from the same homogeneous pollen pool showing no bias towards pollen sources near that part of the canopy. Overall findings suggest low-density Q. lobata populations show steep decay of SDD. Policies and ordinances governing the amount of allowable tree removal of savannah oak populations should recommend the preservation of local clusters of adults, as well as some connectivity among clusters. 相似文献
103.
The National Environmental Policy Act (NEPA) of 1970 changed the landscape of natural resource management by requiring federal agencies to assess the environmental consequences of their proposed actions and to include the public in their decision-making processes. Of all federal agencies in the United States, the Forest Service prepares the most Environmental Impact Statements under NEPA. The U.S. Forest Service manages the National Forest System, public forestlands comprising approximately 9% of the United States land area. The overall objectives of this study were to (1) determine the litigants, success rates, and management activities disputed for NEPA litigation involving the Forest Service from 1970 to 2001 and (2) examine differences and patterns in cases among the U.S. District, Circuit, and Supreme Courts. Methods include a historical analysis of published court cases and results show an increasing trend in the number of NEPA-Forest Service cases in the federal courts. Environmental groups were the most common litigants in NEPA-Forest Service cases and timber harvesting, management plans, and endangered species were the subject of the majority of cases in both the U.S. District Court and the U.S. Circuit Court of Appeals. The Forest Service won a preponderance of cases in which they were involved with success rates of 60% in U.S. District Court, 57% in the U.S. Circuit Court of Appeals, and 100% in the U.S. Supreme Court. 相似文献
104.
Black spot disease, incited by the fungus Diplocarpon rosae Wolf, is the most important disease of roses (Rosa hybrida L.) in the outdoor landscape. Though partial resistance exists in cultivated germplasm, the genetic basis of this trait has
not yet been elucidated. Six diploid and six tetraploid rose cultivars were crossed in two factorial combining ability arrays.
Whole plant and detached leaf inoculation methods were used to assess partial resistance under two different disease pressures
using a characterized single-spore isolate. Parents from both arrays had significant general combining ability effects across
multiple inoculation methods and environments. Specific combining ability was not significant for either array. Parent per
se performance was highly correlated with progeny performance on a family mean basis. High positive correlations among whole
plant and detached leaf inoculation methods indicate that detached leaf assays can substitute for whole plant assays. Based
on these results, a breeding strategy including parental selection and early, among-family selection is proposed. To our knowledge,
this is the first investigation of combining ability for disease resistance in rose. 相似文献
105.
T B Whitaker J W Dickens F G Giesbrecht 《Journal of the Association of Official Analytical Chemists》1986,69(3):508-510
The amount of aflatoxin extracted from raw peanuts by using the water-slurry modification of AOAC Method II was determined for 49 different combinations of methanol concentrations and solvent/peanut ratio. Results indicate that the amount of aflatoxins B1 and B2 extracted from raw peanuts is a function of both methanol concentration and solvent/peanut ratio, and a cubic equation was developed, using regression techniques, to describe the combined effects. From the functional relationship, the predicted methanol concentration and solvent/peanut ratio that extracts the most aflatoxin B1 was computed to be 60.0% and 10.8 mL solvent/g peanuts, respectively. This combination extracted 12.1% more aflatoxin than did AOAC Method II. 相似文献
106.
B R Whitaker K M Wright S L Barnett 《Veterinary Clinics of North America: Exotic Animal Practice》1999,2(2):265-90, v-vi
The veterinarian presented with an amphibian patient must be prepared to assess both the animal's medical condition and its husbandry record; good health is inextricably linked to proper care and diet. This article provides the clinician with guidelines for maintaining amphibians in captivity, including information on climate control and lighting, housing and cage enrichment, and nutrition. The article also covers questions to ask when taking a history, methods of restraint, and practical advice on the equipment and techniques used to conduct a complete physical examination of the amphibian patient. 相似文献
107.
Comprehensive hematologic and biochemical analyses were conducted on blood from 23 male and 31 female clinically stable captive mugger crocodiles (Crocodylus palustris). Erythrocyte mean corpuscular volume (MCV), potassium, cholesterol, and calcium concentrations were significantly greater in juvenile males than in juvenile females, but no significant differences were determined between parameters of subadult males and subadult females. The mean WBC count and mean heterophil count were significantly higher in adult males than in adult females. Mean uric acid concentration was significantly greater in adult females than in males. Mean erythrocyte count was significantly higher in adults than in juveniles. Adult mean WBC and lymphocyte counts were significantly lower than those of both juveniles and subadults. Subadults had significantly lower mean eosinophil counts than both adults and juveniles. Subadults had significantly lower mean alkaline phosphatase activities than juveniles, whereas the adults had significantly lower aspartate aminotransferase and alanine aminotransferase activities than other groups. Lactate dehydrogenase activities were significantly lower for subadults than for juveniles and adults. Cholesterol concentrations were significantly higher for subadults and juveniles compared with adults. Triglyceride concentration was significantly lower for subadults and highest for juveniles. Glucose concentrations were significantly higher for adults. Blood urea nitrogen was significantly lower for subadults than for both adults and juveniles. Uric acid concentrations were significantly higher for juveniles than for the subadults and adults. The subadult animals also had a significantly lower potassium concentration. The results obtained were then compared with known values for other crocodilian species. 相似文献
108.
Thomas W. Whitaker 《Euphytica》1962,11(3):273-281
F1, F2, and backcross progenies derived from an interspecific cross between Cucurbita lundelliana and C. maxima were analyzed by using the hybrid index method of Anderson. The results suggest that C. lundelliana is dominant for most characters. There is a good deal of sterility, particularly in the backcross to C. maxima. It appears feasible, however, to transfer such characters as powdery mildew resistance, perennial habit, solid placenta, etc. from C. lundelliana to C. maxima by conventional plant-breeding techniques. The mean pollen fertility for the F1, F2 and backcross to C. lundelliana was respectively 17.6%, 28.4% and 5.2%: for the backcross to C. maxima. 65.9%. 相似文献
109.
110.
Megan M. Mathey Sonali Mookerjee Lise L. Mahoney Kazim Gündüz Umesh Rosyara James F. Hancock Philip J. Stewart Vance M. Whitaker Nahla V. Bassil Thomas M. Davis Chad E. Finn 《Euphytica》2017,213(5):112
Ten seedlings from 36 crosses representing eastern and western North American short day and remontant genotypes were evaluated in 2011 and 2012 in California, Michigan, New Hampshire and Oregon, for phenology, flower related traits, plant characteristics, fruit characteristics and fruit chemistry traits. There was significant variability among genotypes, locations and evaluation year for most of the characteristics; however, few genotype × location and genotype × year interactions were detected. General combining ability variance components were significant for all traits and greater than SCA variance components for peduncle length, total flowering weeks, flowering cycles, truss size, growing degree days for harvest data, remontancy, achene position, ease of capping, fruit weight, percent soluble solids, titratable acidity and soluble solids/titratable acidity. ‘Sarian’ was identified as the best contributing parent for remontancy. Narrow-sense heritability estimates were moderate to high (0.33–0.78) for total flowering weeks, flowering cycle, truss size, remontancy, number of runners, fruit weight, pH, and titratable acidity. Having a better understanding of these attributes will provide breeders guidance on the most effective breeding strategies for incorporating superior traits from this germplasm into their programs. 相似文献