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71.
"Brain death," the determination of human death by showing the irreversible loss of all clinical functions of the brain, has become a worldwide practice. A biophilosophical account of brain death requires four sequential tasks: (1) agreeing on the paradigm of death, a set of preconditions that frame the discussion; (2) determining the definition of death by making explicit the consensual concept of death; (3) determining the criterion of death that proves the definition has been fulfilled by being both necessary and sufficient for death; and (4) determining the tests of death for physicians to employ at the patient's bedside to demonstrate that the criterion of death has been fulfilled. The best definition of death is "the cessation of functioning of the organism as a whole." The whole-brain criterion is the only criterion that is both necessary and sufficient for death. Brain death tests are used only in the unusual case in which a patient's ventilation is being supported. Brain death critics have identified weaknesses in its formulation. But despite its shortcomings, the whole-brain death formulation comprises a concept and public policy that make intuitive and practical sense and that has been well accepted by many societies.  相似文献   
72.
Ethanol was determined by gas chromatography in a variety of tissues and body fluids secured at autopsy in 61 cases. The specimens tested included right and left heart blood, femoral blood, pericardial fluid, cerebrospinal fluid, vitreous humor, urine, stomach contents, and brain. Statistical analysis of the cases revealed no significant differences among the various blood sites tested. However, the variations in blood ethanol concentrations among the various sampling sites within each case were as follows: 40 cases showed differences of less than 25%; 16 cases revealed variability between 25% and 50%, 4 cases had differences exceeding 50%. In one case, satisfactory blood analyses could not be accomplished. The larger variances occurred especially in those instances in which stomach alcohol concentration was 0.50% or greater. In one case, the variability amongst the different blood sites exceeded 400% (femoral blood--0.043%, right atrium--0.070%, root of aorta--0.156%); the brain was 0.050%, and the stomach contents was 1.2%. For all 61 cases, variances in blood alcohol content among the different sampling sites in a single cadaver ranged from 1.8 to 428%.  相似文献   
73.
Conclusion The Regulations appear to have reinforced the protection available to software producers under United Kingdom law. The provisions of the Software Directive and the Regulations are complex and not without significant inconsistencies which are likely to prove to be a source of litigation. The drafters of the Regulations chose, unlike many of its European partners, not to adopt the wording of the Software Directive but to write their own interpretation, adding an element of uncertainty to the law in this area, which is perhaps inevitable bearing in mind the linguistic problems of translating and interpreting any directive coupled with the ambiguity and omission of definitions of several key terms. More important, however, than any academic argument will be the practical impact of the new law and its effectiveness in achieving its aim.  相似文献   
74.
For helpful suggestions and criticism I am grateful to Delf Buchwald (Göttingen), Malte Dießelhorst (Göttingen), Ralf Dreier (Göttingen), Bonnie Litschewski Paulson (Göttingen and St. Louis), Martin Schulte (Münster), Alexander Somek (Vienna), and Kenneth I. Winston (Boston). In correspondence, Walter Ott (Zurich) and Carola Vulpius (Dresden) responded in a most helpful way to my queries.  相似文献   
75.
76.
This paper examines nine cases of “spinback,” the flow back to laboratories of technical advantage from technology transfer activities. The benefits revealed in the cases are discussed and assessed for their value to the participating laboratories and the scientists involved. The objective of this study was to explore and test the feasibility of undertaking a comprehensive study of the value of spinback in order to encourage support for technology transfer activities by middle management in a laboratory. Spinback is defined as the phenomenon by which scientists’ and engineers’ participation in technology utilization activities results in a technically valuable flow back to their laboratories or organizations, thereby increasing or improving techical capability. It was anticipated that this exploration would provide evidence that the phenomenon does occur, with important consequences for the organization.  相似文献   
77.
78.
In the forensic science laboratory, the recovery of spermatozoa from vaginal swabs, or vaginal cells from penile swabs, can help determine if sexual intercourse may have taken place. There are several methods used to recover spermatozoa and cells from the swabs before visualisation on a microscope slide and most of these methods use water. Phosphate buffered saline (PBS) is a non-toxic solution used in many biological laboratories. Unlike water, PBS prevents cells rupturing or shrivelling up due to osmosis. This study demonstrates that PBS can be used for the extraction of spermatozoa and cells from swabs and that PBS does not affect subsequent DNA profiling.  相似文献   
79.
Citizen suit provisions, which give proregulatory interests access to the federal courts, can be used by Congress to increase the courts' role in regulatory policy. I analyze 284 environmental regulation bills reported favorably out of committee and show that committee support for citizen suits is a function of the committee's policy goals and the political context in which the bills are generated. These findings indicate that Congress deliberately uses judicial procedures as instruments of political control and that scholars examining judicial policymaking must include legislative goals in the list of explanatory factors.  相似文献   
80.
柔嫩艾美球虫杨凌株表面抗原SAG10基因的克隆与原核表达   总被引:2,自引:0,他引:2  
从柔嫩艾美球虫第二代裂殖子总RNA中扩增EtSAG10基因,与pGEM-T Easy载体连接后转化大肠杆菌(E.coli)DH5α,筛选阳性克隆,扩增不含N端信号肽的编码序列,分别插入表达载体pET-32a( )和pMAL-c2X,转化至E.coliRosetta,以IPTG诱导表达。结果表明,pET-32a( )-EtSAG10在E.coliRosetta中的表达产物约占菌体总蛋白的43%,融合蛋白分子质量约为47 ku,以包涵体形式存在;而pMAL-c2X-EtSAG10在E.coliRosetta中表达的重组蛋白为可溶性,表达产物约占菌体总蛋白的35%,融合蛋白分子质量约为69 ku。以表达的可溶性EtSAG10重组蛋白100μg/只肌肉注射免疫雏鸡,攻虫后以盲肠病变计分、盲肠卵囊数(OPG)、相对增重率和抗球虫指数(ACI)评价,免疫组相对盲肠卵囊产量为47.7%,抗球虫指数由86.79提高至152.13。提示,重组表达的EtSAG10可诱导雏鸡产生一定的抗球虫免疫保护。  相似文献   
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