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1.
AIMS: To determine if abdominal insufflation with medical air will improve oxygenation and ventilation parameters when compared to insufflation with CO2 in xylazine-sedated sheep undergoing laparoscopic artificial insemination (AI).METHODS: Forty-seven sheep underwent oestrus synchronisation and were fasted for 24 hours prior to laparoscopic AI. Each animal was randomised to receive either CO2 or medical air for abdominal insufflation. An auricular arterial catheter was placed and utilised for serial blood sampling. Respiratory rates (RR) and arterial blood samples were collected at baseline, after xylazine (0.1?mg/kg I/V) sedation, 2 minutes after Trendelenburg positioning, 5 minutes after abdominal insufflation, and 10 minutes after being returned to a standing position. Blood samples were collected in heparinised syringes, stored on ice, and analysed for arterial pH, partial pressure of arterial O2 (PaO2), and CO2 (PaCO2). The number of ewes conceiving to AI was also determined.RESULTS: Repeated measures ANOVA demonstrated temporal effects on RR, PaO2, PaCO2 and arterial pH during the laparoscopic AI procedure (p<0.001), but no difference between insufflation groups (p>0.01). No sheep experienced hypercapnia (PaCO2>50?mmHg) or acidaemia (pH<7.35). Hypoxaemia (PaO2<70?mmHg) was diagnosed during the procedure in 14/22 (64%) ewes in the CO2 group compared with 8/23 (35%) ewes in the medical air group (p=0.053). Overall, 15/20 (75%) ewes in the CO2 group conceived to AI compared with 16/22 (72.7%) in the medical air group (p=0.867).CONCLUSIONS AND CLINICAL RELEVANCE: There were no statistical or clinical differences in RR, PaO2, PaCO2, pH, or conception to AI when comparing the effects of CO2 and medical air as abdominal insufflation gases. None of the sheep experienced hypercapnia or acidaemic, yet 42% (19/45) of sheep developed clinical hypoxaemia, with a higher percentage of ewes in the CO2 group developing hypoxaemia than in the medical air group. Based on the overall analysis, medical air could be utilised as a comparable alternative for abdominal insufflation during laparoscopic AI procedures. 相似文献
2.
Fiona Da Riz Paul Higgs Guillaume Ruiz 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):611
Cobalamin concentration is often assessed in clinical practice but little is known about the significance of hypercobalaminemia. The objective of this retrospective study was to identify the conditions associated with hypercobalaminemia in dogs and to investigate association with clinicopathological variables. Medical records of dogs having serum cobalamin measured between 2016 and 2018 were reviewed. One hundred sixty dogs were included and 47 (29%) showed hypercobalaminemia. Dogs with hypercobalaminemia had gastrointestinal (57%), hepatic (11%), neurological (11%), endocrine (9%), renal (4%), pancreatic (2%), and miscellaneous (6%) diseases. Overall, 11% had neoplasia. This distribution was not significantly different from that for hypocobalaminemic and normocobalaminemic dogs. There were significantly more dogs with hyperfolatemia in the hypercobalaminemia group. These results suggest that in clinical practice hypercobalaminemia is commonly identified in gastrointestinal and hepatic disease in dogs, but can also be seen with endocrine and neurological conditions. The frequency of hyperfolatemia alongside hypercobalaminemia may reflect common metabolic pathways. 相似文献
3.
In the Upper Zambezi and Okavango ecoregions, Brycinus lateralis, Hepsetus cuvieri, Schilbe intermedius and Serranochromis macrocephalus are important in subsistence fisheries, while S. intermedius and S. macrocephalus are often caught in commercial catches. Despite their importance, there is little information on their age and growth and age validation. Growth zone deposition rate in otoliths of B. lateralis, H. cuvieri, S. intermedius and S. macrocephalus was validated as annual using edge analysis in this study. Annual deposition of growth zones was corroborated by a fluorochrome marking experiment. Both methods demonstrated that one growth zone was deposited annually. Edge analysis demonstrated that the highest proportion of opaque zones was detected between August and December, most likely as a result of slow growth during lower temperature water during the preceding winter. With growth zone deposition validated as annual, future research should focus on determining the growth, maturity and mortality rates of these species, parameters which are important for their management. 相似文献
4.
J. Gordon Bell Douglas R. Tocher Fiona M. MacDonald John R. Sargent 《Fish physiology and biochemistry》1994,13(2):105-118
Three practical-type diets utilizing fishmeal and casein as the protein sources and containing fish oil (FO), safflower oil
(SO) or linseed oil (LO) were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.2 g for a period of 12 weeks. No differences in final weight, mortality or development of pathological
lesions were evident either between duplicate tanks or between dietary treatments over this period. Fish fed diets containing
SO and LO contained significantly greater amounts of liver triacylglycerol compared to fish fed FO. The major C18 polyunsaturated fatty acids (PUFA) in SO and LO diets, 18:2(n-6) and 18:3(n-3) respectively, were readily incorporated into
both total lipid and individual phospholipids of turbot tissues. There was no accumulation of the Δ6-desaturation products
of these fatty acids, namely 18:3(n-6) and 18:4(n-3), in any of the tissues examined. The products of elongation of 18:2(n-6)
and and 18:3(n-3), 20:2(n-6) and 20:3(n-3) respectively, accumulated in both total lipid and phospholipids with the highest
levels of 20:2(n-6) in liver PC and 20:3(n-3) in liver PE. Eicosapentaenoic acid [EPA, 20:5(n-3)] levels exceeded those of
arachidonic acid [AA, 20:4(n-6)] in phosphatidylinositol (PI) from liver and gill of fish fed LO. EPA levels in liver PI from
fish fed LO were 3-fold and 2-fold greater than SO-fed and FO-fed fish, respectively. Fish fed diets containing SO and LO
had significantly reduced levels of AA in liver and muscle total lipid and lower AA in individual phospholipid classes of
liver and gill compared to FO-fed fish. The concentration of thromboxane B2 was significantly reduced in plasma and isolated gill cells stimulated with calcium ionophore A23187 of fish fed SO and LO
compared to those fed FO. Prostaglandin E produced by isolated gill cells stimulated with A23187 was significantly reduced
in fish fed both SO and LO compared to fish fed FO. 相似文献
5.
We argue that thematic resolution, i.e., the level of categorical detail of a thematic map expressed by the number of classes
included in the map legend, is an inherent component of the scale at which a landscape is analyzed. Changing the number of
classes can change the configuration of the patch mosaic as much as changing the grain does. We address recent calls in this
and other journals to deepen research in this topic. In particular, we report how thematic resolution affects the patchiness
of mosaics representing natural landscapes, which have seldom been studied in this respect. We selected seven 50 × 50 km landscapes
within national parks, each representative of a world biome. We applied an object-based unsupervised classification to Landsat
TM imagery of these landscapes using increasing numbers of classes, between 2 and 50, and derived curves of mean patch size
and patch density for each site. Our results are consistent with previous findings in that the patchiness of output mosaics
increases monotonically with increasing thematic resolution, with a higher rate of increase up to eight classes that declines
until it becomes roughly constant for more than 16 classes. However, this constant rate of increase is still considerable,
meaning that, at least for natural landscapes, there is no threshold beyond which the patch-mosaic model is independent of
the conceptual filter applied. This dependence on human fiat calls for re-thinking the patch-mosaic paradigm. 相似文献
6.
Assessment of EST- and genomic microsatellite markers for variety discrimination and genetic diversity studies in wheat 总被引:22,自引:0,他引:22
Fiona Leigh Vince Lea John Law Petra Wolters Wayne Powell Paolo Donini 《Euphytica》2003,133(3):359-366
It is likely that in the near future sequence information from sequencing programmes and EST libraries will generate an abundance
of genic microsatellite markers. This study is focused on the assessment of their likely impact and performance vis-à-vis
their genomic counterparts. Microsatellites from two sources were used to assess the genetic diversity in 56 old and new varieties
of bread wheat on the UK Recommended List. A set of 12 microsatellite markers generated from genomic libraries and 20 expressed
sequence tag (EST)-derived microsatellites were used in the study, and the performance of both marker sets assessed. The EST-derived
or genic microsatellites delivered fingerprints of superior quality, amplifying clear products with few stutter bands. Diversity
levels as revealed bygenic microsatellites are similar to the few published results. The PIC values for the genic markers
were generally lower than those calculated for the genomic microsatellites, though advantages of both marker classes for variety
identification applications are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Papantoniou E Hammond EW Tsiami AA Scriven F Gordon MH Schofield JD 《Journal of agricultural and food chemistry》2003,51(4):1057-1063
Fractionation and reconstitution techniques were used to study the contribution of endogenous flour lipids to the quality of semisweet (Rich Tea-type) biscuits. Biscuit flour was defatted with chloroform and baked with bakery fat but without endogenous lipid addition. Semisweet biscuits baked from defatted flour were flatter, denser, and harder and showed collapse of gas cells during baking when compared with control biscuits. Defatted flour semisweet doughs exhibited a different rheological behavior from the control samples showing higher storage and loss moduli (G' and G' ' values), that is, high viscoelasticity. Functionality was restored when total nonstarch flour lipids were added back to defatted flour. Both the polar and nonpolar lipid fractions had positive effects in restoring flour quality, but the polar lipid fraction was of greatest benefit. Both fractions were needed for complete restoration of both biscuit quality and dough rheological characteristics. 相似文献
8.
A recent survey of insecticide resistance in two of the most problematic pests in UK glasshouses revealed some new developments. At least some individuals in all UK samples of Trialeurodes vaporariorum that were tested resisted the insect growth regulator (IGR) buprofezin. The most strongly resistant strains were unaffected by the field application rate of this compound, and even samples from populations that had never been exposed to buprofezin contained individuals that survived the highest concentration applied (10,000 mg litre-1). The field rate of buprofezin was shown to select for resistance through vapour action alone. The benzophenylurea teflubenzuron, an unrelated IGR, was cross-resisted by buprofezin-resistant individuals. There was no evidence of resistance to imidacloprid, but all T vaporariorum strains tested, regardless of origin, exhibited a high innate tolerance to nicotine, when compared with another whitefly species, Bemisia tabaci. Marked resistance to fenbutatin oxide and tebufenpyrad was found in single glasshouse populations of Tetranychus urticae, but these compounds and abamectin appeared to remain highly effective against all other strains collected. 相似文献
9.
10.
Testicular seminoma associated with torsion of the spermatic cord in two cryptorchid stallions 总被引:1,自引:0,他引:1
R J Hunt W Hay C Collatos E Welles 《Journal of the American Veterinary Medical Association》1990,197(11):1484-1486
Two adult horses had colic attributable to spermatic cord torsion and strangulation of abdominally retained neoplastic testes. Both horses had caudal abdominal soft tissue masses palpable per rectum. One horse was treated successfully by surgical removal of the testis, and the other was euthanatized without treatment. Histopathologic diagnosis of the involved testes was testicular seminoma. Spermatic cord torsion of an abdominally retained testis should be considered in the differential diagnosis of signs of abdominal pain in cryptorchid stallions, especially those with a palpable caudal abdominal mass. 相似文献