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91.
梅花鹿鹿茸不同产品中氨基酸含量的比较 总被引:1,自引:0,他引:1
通过对二杠鹿茸、三杈鹿茸、鹿茸片、鹿茸血、鹿角、鹿角盘等鹿茸产品中氨基酸含量的测定研究,结果表明:鹿茸血中氨基酸含量最高,鹿茸片中的氨基酸含量次之,三杈鹿茸中的氨基酸含量高于二杠鹿茸中氨基酸含量,鹿花盘中的含量高于鹿角中的氨基酸含量,从而为鹿茸这一动物性中药材资源的功能评价、药理作用提供科学理论依据。 相似文献
92.
Ruth F. CARDEN Caitríona M. CARLIN Ferdia MARNELL Damian MCELHOLM John HETHERINGTON Martin P. GAMMELL 《Mammal Review》2011,41(4):313-325
- 1 Throughout Europe, the range of many deer species is expanding. We provide current distribution maps for red deer Cervus elaphus, sika Cervus nippon, fallow deer Dama dama and muntjac deer Muntiacus sp. in Ireland, and estimates of range expansion rates for red deer, sika and fallow deer.
- 2 There was a considerable expansion in the ranges of red deer, sika and fallow deer between 1978 and 2008. The compound annual rate of expansion was 7% for red deer, 5% for sika and 3% for fallow deer. The total range increase was 565% for red deer, 353% for sika and 174% for fallow deer. The potential implications of these expansions are discussed.
- 3 There are unknown numbers of red‐sika hybrid deer in some parts of Ireland. Range expansion is likely to lead to further hybridizations with implications for the genetic integrity of deer stocks.
- 4 Sightings of free‐roaming muntjac deer were first recorded in 2007. The distribution of confirmed sightings of single and multiple animals in the eastern region of Ireland suggests multiple releases.
- 5 Deer are already impacting on both the economic and biodiversity values of habitats in Ireland, where, at present, no sustainable deer management policy exists.
93.
Over a 5-year period (1997-2001) the population densities of Ixodes pacificus Cooley & Kohls (Acari: Ixodidae) nymphs infected with spirochaetes of Borrelia burgdorferi sensu lato (s.l.) were evaluated in areas of 2000 ha at two localities (CHR, nine sites; HREC, seven sites) 25 km apart in Mendocino County, north-western California. The 5-year median density of infected nymphs was significantly higher at CHR than at HREC (0.51 vs. 0.09 per 100 m(2) and site-specific yearly densities exceeding one infected nymph per 100 m2 were 10-fold more likely to occur at CHR than at HREC. The importance of long-term data in acarologic risk assessment was demonstrated by significantly higher median yearly densities of infected nymphs at CHR from 1997 to 1999, whereas both areas had similar densities during 2000-2001. Overall, the causative agent of Lyme borreliosis in North America, B. burgdorferi Johnson et al. sensu stricto (s.s.) accounted for 76% of 46 genetically characterized B. burgdorferi s.l. infections from I. pacificus nymphs. Tremendous variability in acarologic risk was recorded within both areas: yearly densities of infected nymphs varied 11-97-fold between sites at CHR and 8-30-fold at HREC. Part of this variation could be explained by environmental traits, most notably deer usage. However, correlations between environmental factors and density of infected nymphs (for CHR and HREC combined) did not necessarily apply when these areas were considered separately. Thus, a Lyme borreliosis ecology model developed in one of these areas needs testing in the other area. 相似文献
94.
95.
David Reby Benjamin D. Charlton Yann Locatelli Karen McComb 《Proceedings. Biological sciences / The Royal Society》2010,277(1695):2747-2753
Across vertebrates, the observation that lower-pitched vocalizations are typically associated with larger and/or higher quality males has lead to the widespread belief that inter- and intra-sexual selection will produce male calls with low fundamental frequencies (F0). Here we investigated the response of oestrous red deer hinds to playback of re-synthesized male roars characterized by either higher than average or lower than average F0. We found that hinds prefer higher rather than lower ‘pitched’ roars, providing, to our knowledge, the first evidence of such a bias in nonhuman mammals. Our findings can be interpreted in relation to previous observations that the minimum F0 of roars is positively correlated with male reproductive success in free-ranging red deer stags, and that across Cervids the F0 of male mating calls shows extreme variability. Females showing preferences for higher-pitched roars might derive genetic benefits through more competitive male offspring. Our results emphasize the need for further investigations of female preferences in mammals in order to better understand the extreme variation of F0 values observed in male sexual calls. 相似文献
96.
MAHMOUD R. HEMAMI† REW R. WATKINSON† ROBIN M. A. GILL‡ PAUL M. DOLMAN† 《Mammal Review》2007,37(3):246-254
- 1 Managing the conservation impacts of deer requires knowledge of their numbers. However, estimating densities in forested areas is problematic, with pellet‐group‐based methods subject to error and uncertainty in estimating defecation and decay rates in addition to sampling variance. Use of thermal imaging equipment allows direct census by distance sampling.
- 2 Densities of introduced Chinese muntjac Muntiacus reevesi and native roe deer Capreolus capreolus were estimated in 12.8 km2 of conifer forest in eastern England by thermal imaging distance transects. Estimated density of introduced muntjac (±95% confidence intervals [CI]: 20 ± 8 km−2) exceeded that of native roe deer (16 ± 6 km−2); 95% CI of c. 40% were achieved in 10 days of fieldwork.
- 3 Density estimates were not sensitive to the number of width bands applied during analysis. Detectability functions differed, with narrower effective strip widths (ESW) for muntjac (74 m) than roe deer (123 m). Thus, it is important to discriminate between species when censusing mixed assemblages. Detectability and ESW also differed among plantation growth stages. Stratification by habitat may therefore improve accuracy of density estimates but would require additional survey effort.
97.
98.
JOHN W. LAUNDRÉ LUCINA HERNÁNDEZ SUSAN G. CLARK 《The Journal of wildlife management》2007,71(2):345-355
ABSTRACT Information on factors affecting population size of pumas (Puma concolor) can be important because their principal prey over most of the western United States are valued big game species (e.g., mule deer [Odocoileus hemionus], elk [Cervus elaphus], and bighorn sheep [Ovis canadensis]). Based on the hypothesis that puma numbers are limited by their food supply, puma populations should track changes in prey abundance by growing exponentially with increases in prey and by declining with a lag response when prey decreases. Additional predictions proposed by researchers are that body mass of pumas, female productivity, kitten survival, and adult survival should decrease after a prey decline. We used a 15-year database from a hunted population of pumas in southern Idaho and northwestern Utah to test these predictions. During the 15-year time span of the database, a major decline in mule deer abundance occurred. Estimates of puma numbers and demographic characteristics came from intensive capture and radiocollaring efforts. We calculated kitten and adult survival with MICROMORT software. We found that adult puma numbers increased exponentially at r = 0.07 during a period of increasing mule deer numbers. Four years after the mule deer abundance declined, puma numbers decreased at a rate of r = −0.06. Body mass of female pumas was lower after the decline in puma numbers (42.6 ± SE = 1.2 kg, n = 40 vs. 40.1 ± 0.64 kg, n = 34, t = 5.06, P = 0.045). Kitten survival was less after the decline in deer abundance (0.573 ± 0.016, n = 30 vs. 0.856 ± 0.015, n = 25, Z = 2.40, P < 0.01). Survival of resident females was significantly less after the decline in puma numbers (0.783 ± 0.03 vs. 0.929 ± 0.019, U = 55.0, P = 0.009). Female productivity did not differ before or after the decline in deer abundance. Our results supported the majority of the predictions concerning the impact of changing deer abundance, which supported the hypothesis that the abundance of mule deer limited our population of pumas. 相似文献
99.
100.
Fully protected pA2′p5′A2′p5′A trimers 1a and 1b have been prepared as prodrug candidates for a short 2′‐5′ oligoadenylate, 2‐5A, and its 3′‐O‐Me analog, respectively. The kinetics of hog liver carboxyesterase (HLE)‐triggered deprotection in HEPES buffer (pH 7.5) at 37° has been studied. The deprotection of 1a turned out to be very slow, and 2‐5A never appeared in a fully deprotected form. By contrast, a considerable proportion of 1b was converted to the desired 2‐5A trimer, although partial removal of the 3′‐O‐[(acetyloxy)methyl] group prior to exposure of the adjacent phosphodiester linkage resulted in 2′,5′→3′,5′ phosphate migration and release of adenosine as side reactions. 相似文献