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951.
Abundance estimates are used to establish baselines, set recovery targets, and assess management actions, all of which are essential aspects of evidence-based natural resource management. For many rare butterflies, these estimates do not exist, and conservation decisions rely instead on expert opinion. Using Bartram’s scrub-hairstreak (Strymon acis bartrami, US Endangered) as a case study, we present a novel comparison of two methods that permit the incorporation of detection probabilities into abundance estimates, distance sampling and double-observer surveys. Additionally we provide a framework for establishing a systematic sampling scheme for monitoring very rare butterflies. We surveyed butterflies monthly in 2013, increasing intensity to weekly when butterflies were detected. We conducted 19 complete, island-wide surveys on Big Pine Key in the Florida Keys, detecting a total of 59 Bartram’s scrub-hairstreaks across all surveys. Peak daily abundances were similar as estimated with distance sampling, 156 butterflies (95 % CI 65–247), and double-observer, 169 butterflies (95 % CI 65–269). Selecting a method for estimating abundance of rare species involves evaluating trade-offs between methods. Distance sampling requires at least 40 detections, but only one observer, while double-observer requires only 10 detections, but two observers. Double-observer abundance estimates agreed with distance sampling estimates, which suggests that double-observer is a reasonable alternative method to use for estimating detection probability and abundance for rare species that cannot be surveyed with other, more commonly used methods. 相似文献
952.
Cristina Ballesteros Lucienne Tritten Maeghan O’Neill Erica Burkman Weam I. Zaky Jianguo Xia Andrew Moorhead Steven A. Williams Timothy G. Geary 《PLoS neglected tropical diseases》2016,10(8)
BackgroundLymphatic filariasis and onchocerciasis are disabling and disfiguring neglected tropical diseases of major importance in developing countries. Ivermectin is the drug of choice for mass drug administration programs for the control of onchocerciasis and lymphatic filariasis in areas where the diseases are co-endemic. Although ivermectin paralyzes somatic and pharyngeal muscles in many nematodes, these actions are poorly characterized in adult filariae. We hypothesize that paralysis of pharyngeal pumping by ivermectin in filariae could result in deprivation of essential nutrients, especially iron, inducing a wide range of responses evidenced by altered gene expression, changes in metabolic pathways, and altered developmental states in embryos. Previous studies have shown that ivermectin treatment significantly reduces microfilariae release from females within four days of exposure in vivo, while not markedly affecting adult worms. However, the mechanisms responsible for reduced production of microfilariae are poorly understood.Conclusion/SignificanceThese changes provide insight into the mechanisms involved in ivermectin-induced reduction in microfilaria output and impaired fertility, embryogenesis, and larval development. 相似文献
953.
One‐year outcomes of an intense workplace cardio‐metabolic risk reduction program among high‐risk employees: The My Unlimited Potential 下载免费PDF全文
Henry Guzman Sankalp Das Doris Brown Chukwuemeka U. Osondu Erica Spatz Brandon Shaffer Joann Santiago‐Charles Teresa Ochoa Joseph Mora Cynthia Gilliam Virginia Lehn Shoshana Sherriff Thinh H. Tran Janisse Post Emir Veledar Theodore Feldman Arthur S. Agatston Khurram Nasir 《Obesity (Silver Spring, Md.)》2016,24(1):71-78
954.
Erica Racchetti Marco Bartoli Cristina Ribaudo Daniele Longhi Luciana E. Q. Brito Mariachiara Naldi Paola Iacumin Pierluigi Viaroli 《Hydrobiologia》2010,652(1):127-137
Benthic consumers influence stream ecosystem structure and function, but these interactions depend on environmental context.
We experimentally quantified the effects of central stoneroller minnows (Campostoma anomalum (Rafinesque) and Meek’s crayfish (Orconectes meeki meeki (Faxon)) on benthic communities using electric exclusion quadrats in Little Mulberry Creek before (June) and during (August)
seasonal stream drying. Unglazed ceramic tiles were deployed in June and August to measure periphyton and invertebrate abundance,
and leafpack decomposition and primary production were also measured in August. Relationships between stoneroller and crayfish
density and the size of consumer effects were evaluated with multiple linear regression models. Average chlorophyll a abundance was greater on exposed than exclusion tiles in August, but not in June. Sediment dry mass, periphyton ash-free
dry mass (AFDM), and chironomid densities on tiles did not differ among treatments in either period. Leaf packs decayed faster
in exposed than exclusion treatments (k
exposed = 0.038 ± 0.013, k
exclusion = 0.007 ± 0.002), but consumer effects were stronger in some pools than others. Leafpack invertebrate biomass and abundance
and tile primary productivity did not differ among treatments. Consumer effects on chlorophyll a were related to crayfish and stoneroller density, and effects on chironomid density were related to stoneroller density.
These results contrast with a previous exclusion experiment in Little Mulberry Creek that demonstrated strong consumer effects.
The influence of stream drying on consumer effects appears to have been reduced by strong spates, underscoring the importance
of conducting multi-year studies to determine the magnitude of variability in ecological interactions. 相似文献
955.
956.
Christian Hafner Erica Di Martino Thomas Stempfl Arndt Hartmann Margaret Knowles 《Experimental cell research》2010,316(12):2008-20785
FGFR3 mutations have recently been identified in several benign epidermal skin lesions such as seborrheic keratosis, epidermal nevus and solar lentigo. The functional consequences of these mutations in human skin are as yet unknown. In this study we analyzed the functional effects of the most common FGFR3 mutation in benign skin tumors, the R248C FGFR3 hotspot mutation, in human HaCaT keratinocytes. The cells were stably transduced with either the R248C or wildtype FGFR3 IIIb cDNA using a retroviral vector system. FGFR3 mutant and wildtype cells showed similar growth rates at subconfluence. However, at confluence FGFR3 mutant keratinocytes revealed a significantly higher cell number than wildtype cells. Furthermore, FGFR3 mutant cells showed significantly lower levels of apoptosis and decreased attachment to fibronectin compared with FGFR3 wildtype cells. Expression of mutant FGFR3 did not alter migration and senescence. Microarray analysis revealed only a few differentially expressed genes between FGFR3 mutant and wildtype keratinocytes. Enhanced phosphorylation of ERK1/2 was observed in confluent R248C mutant HaCaT cells compared with wildtype keratinocytes. Our results suggest that an increased cell number at confluence along with a decreased apoptosis may contribute to the development of acanthotic tumors in FGFR3 mutant skin in vivo. 相似文献
957.
Kali D. Saxton-Shaw Jeremy P. Ledermann Joan L. Kenney Erica Berl Alan C. Graham Joel M. Russo Ann M. Powers John-Paul Mutebi 《PloS one》2015,10(6)
The first known outbreak of eastern equine encephalitis (EEE) in Vermont occurred on an emu farm in Rutland County in 2011. The first isolation of EEE virus (EEEV) in Vermont (VT11) was during this outbreak. Phylogenetic analysis revealed that VT11 was most closely related to FL01, a strain from Florida isolated in 2001, which is both geographically and temporally distinct from VT11. EEEV RNA was not detected in any of the 3,905 mosquito specimens tested, and the specific vectors associated with this outbreak are undetermined. 相似文献
958.
In this protocol, social motivation is measured in mice through a pair of operant conditioning paradigms. To conduct the experiments, two-chambered shuttle boxes were equipped with two operant levers (left and right) and a food receptacle in one chamber, which was then divided from the second chamber by an automated guillotine door covered by a wire grid. Different stimulus mice, rotated across testing days, served as a social stimulus behind the wire grid, and were only visible following the opening of the guillotine door. Test mice were trained to lever press in order to open the door and gain access to the stimulus partner for 15 sec. The number of lever presses required to obtain the social reward progressively increased on a fixed schedule of 3. Testing sessions ended after test mice stopped lever pressing for 5 consecutive minutes. The last reinforced ratio or breakpoint can be used as a quantitative measure of social motivation. For the second paradigm, test mice were trained to discriminate between left and right lever presses in order to obtain either a food reward or the social reward. Mice were rewarded for every 3 presses of each respective lever. The number of food and social rewards can be compared as a measurement of the value placed upon each reward. The ratio of each reward type can also be compared between mouse strains and the change in this ratio can be monitored within testing sessions to measure satiation with a given reward type. Both of these operant conditioning paradigms are highly useful for the quantification of social motivation in mouse models of autism and other disorders of social behavior. 相似文献
959.
960.
Sarah J. Neal Webb Jennifer P. Bridges Erica Thiele Susan P. Lambeth Steven J. Schapiro 《American journal of primatology》2020,82(3):e23109
Due to advances in captive nonhuman primate (NHP) medical care, the number of geriatric chimpanzees (≥35-years old) is growing. With old age comes a variety of physical conditions, including arthritis, stroke, and mobility impairments. Programs aimed at enhancing the welfare of geriatric chimpanzees are now quite common, but there are few published empirical evaluations of the efficacy of such programs. The current study aimed to create, implement, and evaluate the effects of participation in a physical therapy (PT) program on physical health, mobility, welfare, and behavior. Nine chimpanzees with mobility impairments participated in personalized PT routines (using positive reinforcement training) twice per week for 5 months. Additionally, nine control chimpanzees (non-mobility-impaired, matched with PT chimpanzees on age and gender) participated in body exam behavior sessions (also using positive reinforcement training) twice per week. All chimpanzees were rated on 14 health, well-being, and behavior items, as well as level of mobility throughout the PT program. Chimpanzees that participated in the PT program showed significant increases in ratings of physical health, well-being, and activity levels across phases of the program. Furthermore, compared to control chimpanzees, PT chimpanzees showed significant increases in ratings of ease of movement. Because raters were not blind to physical therapy treatment, our results represent an initial evaluation of the program that may suggest that participation in the PT program has physical, behavioral, and welfare benefits. Assessments of novel geriatric-focused care strategies and programs are essential to further enhance the welfare of the captive chimpanzee population, which is currently comprised of many geriatric animals, whose proportion of the captive population will only increase. 相似文献