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91.
Preparation of Agglutinating Antisera and Fluorescent-Antibody Conjugates Against Pasteurella tularensis in Equines 总被引:1,自引:0,他引:1 下载免费PDF全文
James H. Green Richard C. Bolin Russell K. Carver Herman Gross Nan Pigott William K. Harrell 《Applied microbiology》1970,19(6):894-897
The serological response in burros and horses to the viable LVS strain of Pasteurella tularensis was studied. High-titered agglutinating antisera and fluorescent-antibody conjugates were obtained in both groups of animals. Maximum titers were obtained in horses 14 to 21 days after the start of vaccination and in burros 21 to 28 days after the start of vaccination. The use of Woodhour's adjuvants or booster inoculations did not result in increased titers. 相似文献
92.
Gwen Arnold 《Wetlands Ecology and Management》2013,21(2):117-129
U.S. Environmental Protection Agency wetland regulators appear to use monetary estimates of the societal value of wetlands relatively infrequently in Section 404 permit review, enforcement, and compensatory mitigation-related activities. While 52 % of surveyed EPA regulators had used such estimates at least once, only 3 % reported using them frequently. Forty-eight percent said they never used them. Survey respondents indicated that their use of such estimates is inhibited by a lack of relevant information, uncertainty about the scientific validity of estimates, and concerns about the scientific and legal defensibility of estimate use. Respondents said they would be more apt to use estimates in regulatory activities if they perceived agency approval for such use and had access to training and best practices. The barriers and inducements EPA regulators cited largely accord with the literature on the science-policy divide and with the argument that regulatory use of valuation estimates may be inappropriate because research in this arena is not sufficiently advanced. 相似文献
93.
94.
In the third millennium B.C., the Indus Civilization flourished in northwest India and Pakistan. The late mature phase (2200-1900 B.C.) was characterized by long-distance exchange networks, planned urban settlements, sanitation facilities, standardized weights and measures, and a sphere of influence over 1,000,000 square kilometers of territory. Recent paleoclimate reconstructions from the Beas River Valley demonstrate hydro-climatic stress due to a weakened monsoon system may have impacted urban centers like Harappa by the end of the third millennium B.C. the impact of environmental change was compounded by concurrent disruptions to the regional interaction sphere. Climate, economic, and social changes contributed to the disintegration of this civilization after 1900 B.C. We assess evidence for paleopathology to infer the biological consequences of climate change and socio-economic disruption in the post-urban period at Harappa, one of the largest urban centers in the Indus Civilization. Bioarchaeological evidence demonstrates the prevalence of infection and infectious disease increased through time. Furthermore, the risk for infection and disease was uneven among burial communities. Corresponding mortuary differences suggest that socially and economically marginalized communities were most vulnerable in the context of climate uncertainty at Harappa. Combined with prior evidence for increasing levels of interpersonal violence, our data support a growing pathology of power at Harappa after 2000 B.C. Observations of the intersection between climate change and social processes in proto-historic cities offer valuable lessons about vulnerability, insecurity, and the long-term consequences of short-term strategies for coping with climate change. 相似文献
95.
The Disinfecting Activity of Methyl Bromide on Various Microbes and Infected Materials under Controlled Conditions 总被引:1,自引:1,他引:0
S ummary : Various micro-organisms were exposed to methyl bromide (MeBr) gas at concentrations of 20–40 mg/l for 20 h at 25°. A significant reduction was obtained in the number of viable bacteria and Aspergillus fumigatus spores, both in the dry form and in semifluid faeces, but no reduction was detected either in dried Bacillus subtilis spores or in one of the bacteriophages tested. The investigation indicates that MeBr is less effective against certain viruses, bacteria and fungi than against coccidial oocysts. The results suggest that fumigation of commercial poultry houses with these concentrations of MeBr may not, in all circumstances, provide the overall reduction of poultry pathogens desired. 相似文献
96.
Yannis P. Papastamatiou Brad M. Wetherbee John O’Sullivan Gwen D. Goodmanlowe Christopher G. Lowe 《Environmental Biology of Fishes》2010,88(4):361-368
The Cookiecutter Shark (Isistius brasiliensis) is an ecto-parasitic predator of numerous large pelagic fish and mammals. However, little is known of its foraging ecology
due to its elusive foraging tactics in the pelagic environment. We used bite scar patterns on pelagic fishes landed at the
Honolulu Fish Auction to assess some of the Cookiecutter Shark foraging habits. Swordfish (Xiphias gladius) had the greatest percentage of bites (87.9 ± 25.0% of individuals had healed scars) followed by Opah (Lampris guttatus, 33.0 ± 8.3% of individuals). Most fish with scars only had one Cookiecutter Shark bite per individual with the exception
of Swordfish, which often had >5 bites per individual. Furthermore, Swordfish had a higher proportion of healed bite scars
meaning they had been attacked while free-swimming. Seasonal changes in the probability of hooked fish being bitten by sharks
were apparent for Swordfish, Bigeye Tuna and Opah. Based on bite scar diameter, larger Cookiecutter Sharks may preferentially
attack Swordfish rather than the other species of pelagic fish. When taken in conjunction with diving behavior of pelagic
fish, and fishing depths, the results add further support to the hypothesis that Cookiecutter Sharks perform diel vertical
migrations. 相似文献
97.
Wataru Takahashi Erida R. Reichert Gwen C. Fung Yoshitsugu Hokama 《Life sciences》1976,19(11):1645-1651
Gamma mobility C-reactive protein (CRP) level was determined in the sera of persons occupationally exposed to pesticides and controls in conjunction with serum protein analysis and other biochemical and enzymologic tests. Workers chronically exposed to dieldrin and pentachlorophenol showed significantly higher prevalence of CRP than the unexposed persons. In addition, the pentachlorophenol-exposed subjects revealed significantly elevated levels of total bilirubin and creatine phosphokinase, although the levels were within normal limits. The results suggest that chronic exposure to pentachlorophenol may have been responsible for the difference in the prevalence of CRP between the pentachlorophenol and control groups. 相似文献
98.
99.
Mary Carver Nico Blüthgen Judy F Grimshaw Glenn A Bellis 《Australian Journal of Entomology》2003,42(2):109-113
Abstract Aphis clerodendri Matsumura is newly recorded from Australia and is known from the Northern Territory, on islands in Torres Strait, and in rainforest in northern Queensland and New South Wales. It induces the formation of leaf pseudogalls on native species of Clerodendrum and is commonly attended by ants, which penetrate and may polydomously nest in the galls. Previously known only from eastern Asia, A. clerodendri can now be classified as native to Australia and Australasian in natural distribution. The species is also newly recorded from Papua New Guinea and Vietnam. 相似文献
100.
Clonal Population Structure and Specific Genotypes of Multidrug-Resistant Campylobacter coli from Turkeys 下载免费PDF全文
C. B. D'lima W. G. Miller R. E. Mandrell S. L. Wright R. M. Siletzky D. K. Carver S. Kathariou 《Applied microbiology》2007,73(7):2156-2164
Commercial turkey flocks in North Carolina have been found to be colonized frequently with Campylobacter coli strains that are resistant to several antimicrobials (tetracycline, streptomycin, erythromycin, kanamycin, and ciprofloxacin/nalidixic acid). Such strains have been designated multidrug resistant (MDR). However, the population structure of MDR C. coli from turkeys remains poorly characterized. In this study, an analysis of multilocus sequence typing (MLST)-based sequence types (STs) of 59 MDR strains from turkeys revealed that the majority of these strains corresponded to one of 14 different STs, with three STs accounting for 41 (69%) of the strains. The major STs were turkey specific, and most (87%) of the strains with these STs were resistant to the entire panel of antibiotics mentioned above. Some (13%) of the strains with these STs were susceptible to just one or two of the antibiotics in this panel. Further subtyping using fla typing and pulsed-field gel electrophoresis with SmaI and KpnI revealed that the major MDR STs corresponded to strains of related but distinct subtypes, providing evidence for genomic diversification within these STs. These findings suggest that MDR strains of C. coli from turkeys have a clonal population structure characterized by the presence of a relatively small number of clonal groups that appear to be disseminated in the turkey production system. In addition, the observed correlation between STs and the MDR profiles of the microbes indicates that MLST-based typing holds potential for source-tracking applications specific to the animal source (turkeys) and the antimicrobial resistance profile (MDR status) of C. coli. 相似文献