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961.
Timothy Y. Liu Jason L. Sanders Fu-Chiang Tsui Jeremy U. Espino Virginia M. Dato Joe Suyama 《PloS one》2013,8(3)
We studied the association between OTC pharmaceutical sales and volume of patients with influenza-like-illnesses (ILI) at an urgent care center over one year. OTC pharmaceutical sales explain 36% of the variance in the patient volume, and each standard deviation increase is associated with 4.7 more patient visits to the urgent care center (p<0.0001). Cross-correlation function analysis demonstrated that OTC pharmaceutical sales are significantly associated with patient volume during non-flu season (p<0.0001), but only the sales of cough and cold (p<0.0001) and thermometer (p<0.0001) categories were significant during flu season with a lag of two and one days, respectively. Our study is the first study to demonstrate and measure the relationship between OTC pharmaceutical sales and urgent care center patient volume, and presents strong evidence that OTC sales predict urgent care center patient volume year round. 相似文献
962.
Isolated SNARE proteins have been shown to confer only partial specificity on the fusion of artificial liposomes that mimic cellular membranes, modifying the SNARE hypothesis of membrane fusion. 相似文献
963.
964.
BACKGROUND: The performance of QuantiBRITE phycoerythrin (PE) beads to standardize quantitation in terms of antibodies bound per cell (ABC) was evaluated by measuring precision, variation across multiple instruments, and variation across time. METHODS: For CD4 quantitation, whole blood was stained with a two-color CD4 reagent using a no-wash/no-lyse format. For CD69 quantitation, whole blood was activated with either phorbol myristate acetate (PMA) or CD3 beads and then stained with a three-color CD69 reagent using a lyse-no-wash format. RESULTS: Across 20 normal donors, the mean CD4 ABC was 51,000. Within-assay precision on quantitation of CD4 ABC on T cells had a coefficient of variance (CV) of <1.0%. Across multiple flow cytometers, quantitation of CD4 ABC had a CV of <5.0%. Within-donor CV on CD4 ABC on 20 donors across 2 months ranged from 1.3% to 3.2%. Within-assay precision on quantitation of CD69 on T cells activated with either PMA or CD3 beads had a CV of <3.0%. Within-donor CV of CD69 ABC across 1 month ranged from 2% to 18% on PMA-activated samples and from 7% to 24% on CD3 bead-activated samples. CONCLUSIONS: Our results indicate that the QuantiBRITE PE beads provide a useful tool for standardized analysis across labs. When used in conjunction with 1:1 conjugates of PE-to-monoclonal antibody, the QuantiBRITE PE beads provide a simple yet robust means of quantitating expression levels in terms of ABC. 相似文献
965.
966.
Arshad Desai Stephen Rogers John P. Incardona Orion Weiner Leonie Ringrose Robert O. J. Weinzierl Vas Ponnambalam Paul A. Slesinger Joe William Ramos Michelle L. Matter Fabrizio d'Adda di Fagagna Neil Hukriede Michael Tsang Vincent Guacci Margarete M. S. Heck 《Current opinion in cell biology》2002,14(6):661
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in cell biology. 相似文献
967.
Molecular mechanical energy refinement of double-helical pentanucleotide tetra-phosphates, d(CGCGC):d(GCGCG), dG5·dC5, d(TATAT):d(ATATA), and dA5 ·dT5 geometries, are presented in order to examine the energy required to open the Nl(purine) …? N3(pyrimidine) distance (base-pair opening) of a Watson-Crick base pair from its normal value of 3 Å to a value of 6 Å. The structural consequences of forcing base-pair opening is sequence dependent. For both dA5 ·dT5 and d(TATAT):d(ATATA), forcing the Nl (AdeKN3 (Thy) distance of the central base pair to a value of 6 Å slides the bases perpendicular to the helix axis forming a low-energy non-Watson-Crick base pair having an adenine amine hydrogen …? thymine carbonyl oxygen hydrogen bond. The two GC sequences behave differently from both AT sequences and differently from each other. Forcing the Nl(Gua) …? N3(Cyt) distance to 6 Å leads to unconventional structures in which hydrogen bonds are formed between the separated bases and the bases above or below them. These structures appear to be trapped in true local minima 6–10 kcal/mol higher in energy than the Watson-Crick structures. Preliminary simulations on d(CGCGC):d(GCGCG) in the Z geometry suggest the reason the Z form may be more refractory to proton exchange than the B form, consistent with experimental observations. 相似文献
968.
Biodesulfurization of organic-sulfur compounds 总被引:2,自引:0,他引:2
A screening assay in which dibenzothiophene (DBT) or DBT-sulfone served as the only bioavailable source of sulfur was used to obtain two new bacterial isolates, strains UM9 and UM3, that desulfurized either substrate. Strain UM9 produced the desulfurized product, 2-hydroxybiphenyl (HBP); no other identifiable desulfurized products or released sulfate or sulfite were detected. Biodesulfurization activity occurred only for growing cultures and was depressed by free sulfate. Neither isolate grew on DBT, DBT-sulfone, or HBP as sole carbon sources. Under optimized conditions of pH and temperature, strain UM9 exhibited up to 35% greater biodesulfurization of DBT-sulfone than did UM3, and both isolates also desulfurized several other organic-sulfur compounds. The kinetics and characteristics of biodesulfurization by either UM3 or UM9, tentatively identified as species ofRhodococcus, indicated mechanisms different from those reported in the literature for other bacteria. 相似文献
969.
Kuang-Yu Chang William J. Riley Nathan Collier Gavin McNicol Etienne Fluet-Chouinard Sara H. Knox Kyle B. Delwiche Robert B. Jackson Benjamin Poulter Marielle Saunois Naveen Chandra Nicola Gedney Misa Ishizawa Akihiko Ito Fortunat Joos Thomas Kleinen Federico Maggi Joe McNorton Joe R. Melton Paul Miller Yosuke Niwa Chiara Pasut Prabir K. Patra Changhui Peng Sushi Peng Arjo Segers Hanqin Tian Aki Tsuruta Yuanzhi Yao Yi Yin Wenxin Zhang Zhen Zhang Qing Zhu Qiuan Zhu Qianlai Zhuang 《Global Change Biology》2023,29(15):4298-4312
The recent rise in atmospheric methane (CH4) concentrations accelerates climate change and offsets mitigation efforts. Although wetlands are the largest natural CH4 source, estimates of global wetland CH4 emissions vary widely among approaches taken by bottom-up (BU) process-based biogeochemical models and top-down (TD) atmospheric inversion methods. Here, we integrate in situ measurements, multi-model ensembles, and a machine learning upscaling product into the International Land Model Benchmarking system to examine the relationship between wetland CH4 emission estimates and model performance. We find that using better-performing models identified by observational constraints reduces the spread of wetland CH4 emission estimates by 62% and 39% for BU- and TD-based approaches, respectively. However, global BU and TD CH4 emission estimate discrepancies increased by about 15% (from 31 to 36 TgCH4 year−1) when the top 20% models were used, although we consider this result moderately uncertain given the unevenly distributed global observations. Our analyses demonstrate that model performance ranking is subject to benchmark selection due to large inter-site variability, highlighting the importance of expanding coverage of benchmark sites to diverse environmental conditions. We encourage future development of wetland CH4 models to move beyond static benchmarking and focus on evaluating site-specific and ecosystem-specific variabilities inferred from observations. 相似文献
970.
Joe C. Gunn Andrew T. Taylor Jeff J. Buckingham Aaron I. Kern James M. Long 《Diversity & distributions》2023,29(10):1299-1314