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91.
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Summary A method is presented for the preparation of immune sera and detection by immunofluorescence ofC. immitis, S. schenckii, B. dermatitidis, C. neoformans, andC. albicans in surgical and autopsy material. Formalin fixation does not affect the antigens of the mycotic agents. There are no cross reactions except withC. immitis andC. neoformans, which can be differentiated by the site of the specific fluorescence in each organism.  相似文献   
93.
Cascading costs:An economic nitrogen cycle   总被引:2,自引:0,他引:2  
The chemical nitrogen cycle is becoming better characterized in terms of fluxes and reservoirs on a variety of scales. Galloway has demonstrated that reactive nitrogen can cascade through multiple ecosystems causing environmental damage at each stage before being denitrified to N2. We propose to construct a parallel economic nitrogen cascade (ENC) in which economic impacts of nitrogen fluxes can be estimated by the costs associated with each stage of the chemical cascade. Using economic data for the benefits of damage avoided and costs of mitigation in the Chesapeake Bay basin, we have constructed an economic nitrogen cascade for the region. Since a single tonne of nitrogen can cascade through the system, the costs also cascade. Therefore evaluating the benefits of mitigating a tonne of reactive nitrogen released needs to consider the damage avoided in all of the ecosystems through which that tonne would cascade. The analysis reveals that it is most cost effective to remove a tonne of nitrogen coming from combustion since it has the greatest impact on human health and creates cascading damage through the atmospheric, terrestrial, aquatic and coastal ecosystems. We will discuss the implications of this analysis for determining the most cost effective policy option for achieving environmental quality goals.  相似文献   
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High risk populations and HIV-1 infection in China   总被引:1,自引:0,他引:1  
INTRODUCTION HIV has spread to all of China’s 31 provinces, autono- mous regions and municipalities, creating one of the fast- est-growing HIV/AIDS epidemics in the world [1,2]. The HIV/AIDS epidemic in China has gone through three phases: the Entry Phase (1985 -1988), the Spreading Phase (1989-1994) and the Expansion Phase (1995- present). The striking increase of HIV-1 infections over the past few years may herald entry into a new fourth phase that will include much larger nu…  相似文献   
96.
Injection drug use and HIV/AIDS transmission in China   总被引:1,自引:0,他引:1  
INTRODUCTION Although sexual transmission accounts for most of the AIDS epidemic globally, HIV/AIDS among injecting drug users (IDUs) is a growing problem worldwide. First de- tected in China in 1989 among drug abusers on the Yunnan border, HIV/AIDS subse…  相似文献   
97.
Cyclooxygenases are encoded by COX-1 and COX-2. They share over sixty percent sequence identity in human and are similar to each other in their crystallographic structures. One major difference in the primary structure of these two isozymes is the presence of eight amino acids in the amino-terminal region of COX-1 that are not present in COX-2. The function of this amino acid sequence is unknown. In this study, a human COX-1 mutant (Δ7aa) with this sequence removed was studied in parallel with COX...  相似文献   
98.
Induced pluripotent stem(iPS) cells can be derived from human somatic cells by cellular reprogramming.This technology provides a potential source of non-controversial therapeutic cells for tissue repair,drug discovery,and opportunities for studying the molecular basis of human disease.Normally,mouse embryonic fibroblasts(MEFs) are used as feeder layers in the initial derivation of iPS lines.The purpose of this study was to determine whether SNL fibroblasts can be used to support the growth of human iPS cell...  相似文献   
99.
It is well known that Tn5B1-4 (commercially known as the High Five) cell line is highly susceptible to baculovirus and provides superior production of recombinant proteins when compared to other insect cell lines.But the characteristics of the cell line do not always remain stable and may change upon continuous passage.Recently an alphanodavirus,named Tn5 Cell Line Virus (or TNCL Virus),was identified in High Five cells in particular.Therefore,we established a new cell line,QB-Tn9-4s,from Trichoplusia ni,wh...  相似文献   
100.
国际植物学墨尔本大会上命名法规的变化   总被引:1,自引:0,他引:1  
2011年7月在第18届国际植物学大会命名法分会上通过了命名法规的一系列重大改动,并在全体大会上得到了接受批准。文中就命名法规的变化进行了简单概述,同时也讨论了这些变化的意义,特别是对菌物研究的意义,以期引起广大研究人员的关注。  相似文献   
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