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1.
Disease     
This paper examines what it is for a condition to be a disease. It falls into two sections. In the first I examine the best existing account of disease (as proposed by Christopher Boorse) and argue that it must be rejected. In the second I outline a more acceptable account of disease. According to this account, by disease we mean a condition that it is a bad thing to have, that is such that we consider the afflicted person to have been unlucky, and that can potentially be medically treated. All three criteria must be fulfilled for a condition to be a disease. The criterion that for a condition to be a disease it must be a bad thing is required to distinguish the biologically different from the diseased. The claim that the sufferer must be unlucky is needed to distinguish diseases from conditions that are unpleasant but normal, for example teething. Finally, the claim that for a condition to be a disease it must be potentially medically treatable is needed to distinguish diseases from other types of misfortune, for example economic problems and legal problems.  相似文献   

2.
Action according to preconceived plans may be life-saving at the scene of accidents involving serious injury to several persons. Severe hemorrhage and respiratory obstruction must be dealt with immediately. As the latter may not be apparent at a glance, it should be looked for specifically. Artificial respiration may be necessary. Spinal puncture is a procedure in first aid which should be carried out at the site of an accident if there are symptoms of cerebral edema or of increased cerebral pressure.Routine plans should be laid to meet the emergency of cardiac arrest on the operating table. The surgeon must be prepared to begin cardiac massage within three minutes in such instances.  相似文献   

3.
Action according to preconceived plans may be life-saving at the scene of accidents involving serious injury to several persons. Severe hemorrhage and respiratory obstruction must be dealt with immediately. As the latter may not be apparent at a glance, it should be looked for specifically. Artificial respiration may be necessary. Spinal puncture is a procedure in first aid which should be carried out at the site of an accident if there are symptoms of cerebral edema or of increased cerebral pressure.Routine plans should be laid to meet the emergency of cardiac arrest on the operating table. The surgeon must be prepared to begin cardiac massage within three minutes in such instances.  相似文献   

4.
An approach is described that enables the germ cell mutagenicity of chemicals to be assessed as part of an integrated assessment of genotoxic potential. It is recommended, first, that the genotoxicity of a chemical be defined by appropriate studies in vitro. This should involve use of the Salmonella mutation assay and an assay for the induction of chromosomal aberrations, but supplementary assays may be indicated in specific instances. If negative results are obtained from these 2 tests there is no need for the conduct of additional tests. Agents considered to be genotoxic in vitro should then be assessed for genotoxicity to rodents. This will usually involve the conduct of a bone marrow cytogenetic assay, and in the case of negative results, a genotoxicity test in an independent tissue. Agents found to be non-genotoxic in vivo are regarded as having no potential for germ cell mutagenicity. Agents found to be genotoxic in vivo may either be assumed to have potential as germ cell mutagens, or their status in this respect may be defined by appropriate germ cell mutagenicity studies. The basis of the approach, which is supported by the available experimental data, is that germ cell mutagens will be evident as somatic cell genotoxins in vivo, and that these will be detected as genotoxins in vitro given appropriate experimentation. The conduct of appropriate and adequate studies is suggested to be of more value than the conduct of a rigid set of prescribed tests.  相似文献   

5.
The methodologies of classical genetics and genetic engineering can be used for the genetic improvement of entomopathogenic nematodes (EPNs) and their symbiont bacteria. Many of the complex behavioural and physiological traits which are targets for genetic improvement are likely to be controlled polygenically, thus selective breeding for improvements to these traits would be appropriate. Much basic research needs to be carried out before researchers will be able to effect improvements to EPNs and their symbionts by genetic engineering. There is a lack of basic information on the genetics and biochemistry of the characteristics that might be altered by transgenic methods in EPNs, and their bacteria, and existing transformation protocols need to be made more effective.  相似文献   

6.
Scientists who use animals in research must justify the number of animals to be used, and committees that review proposals to use animals in research must review this justification to ensure the appropriateness of the number of animals to be used. This article discusses when the number of animals to be used can best be estimated from previous experience and when a simple power and sample size calculation should be performed. Even complicated experimental designs requiring sophisticated statistical models for analysis can usually be simplified to a single key or critical question so that simple formulae can be used to estimate the required sample size. Approaches to sample size estimation for various types of hypotheses are described, and equations are provided in the Appendix. Several web sites are cited for more information and for performing actual calculations  相似文献   

7.
《Ibis》1994,136(2):257-259
These are collated by Gwen Bonham, the Union's Administrative Secretary. Requests for the publication of information or other required assistance will be sympathetically considered. Publicity will gladly be given to relevant grants and awards that can be applied for, and to new societies which might be of interest to our readers. Details of conferences and meetings will also be included if sent to the Administrative Secretary at least 6 months in advance of the event. All items for Current Notes and Notices should be sent to the BOU, % The Natural History Museum, Tring, Hertfordshire HP23 6AP, UK .  相似文献   

8.
Transgenesis would be greatly streamlined if sperm cells could be used as transgene vectors. Attempts to 'force' sperm cells to take up transgenes may be more worthy of further study than 'autouptake' attempts. However, thorough proof of its effectiveness will be required if sperm cell-mediated gene transfer is to be accepted, given the evolutionary implications associated with the possibility of sperm cells being able to transfer exogenous DNA.  相似文献   

9.
D Salsburg 《Biometrics》1986,42(3):671-674
New drugs that will be investigated in the future are expected to deal with chronic diseases, where the number of patients available for controlled clinical trials will be small and where the long-term sequelae that it is hoped will be ameliorated take a long time to occur. Thus, it would be useful to construct powerful tests of hypotheses that can be used to compare subtle intermediate measures of change in condition. This paper examines the probabilistic characteristics of these measures and the changes in them that might be expected from drug therapy.  相似文献   

10.
本文介绍一种酸性琼脂电泳方法。它可以比较容易地分开血红蛋白A和血红蛋白F、可将异常血红蛋白分成两大类,即酸性电泳阳性和酸性电泳阴性两类异常血红蛋白。此法在血红蛋白病中比较常用的是鉴别血红蛋白S与其它电泳速度相同的变异物,帮助诊断镰状细胞贫血。在常见病方面,这种方法还能分开血红蛋白A和糖基化血红蛋白,用来帮助诊断糖尿病。  相似文献   

11.
The x-ray exposure at which significant radiation damage occurs has been quantified for frozen crystals of bacteriorhodopsin. The maximum exposure to approximately 11-keV x-rays that can be tolerated for high-resolution diffraction experiments is found to be approximately 10(10) photons/microm(2), very close to the value predicted from limits that were measured earlier for electron diffraction exposures. Sample heating, which would further reduce the x-ray exposure that could be tolerated, is not expected to be significant unless the x-ray flux density is well above 10(9) photons/s-microm(2). Crystals of bacteriorhodopsin that contain approximately 10(11) unit cells are found to be large enough to give approximately 100 high-resolution diffraction patterns, each covering one degree of rotation. These measurements are used to develop simple rules of thumb for the minimum crystal size that can be used to record x-ray diffraction data from protein microcrystals. For work with very small microcrystals to be realized in practice, however, it is desirable that there be a significant reduction in the level of background scattering. Background reduction can readily be achieved by improved microcollimation of the x-ray beam, and additional gains can be realized by the use of helium rather than nitrogen in the cold gas stream that is used to keep the protein crystals frozen.  相似文献   

12.
If the sovereignty issue can be shelved, solved, or resolved, the six claimant states of the South China Sea will have to establish a series of international regimes. The following questions need to be answered: Do all the claimants understand the concept of international regimes? Would the regimes be imposed? Would there be hegemon(s) in the South China Sea? If so, which country or multiple entities will be involved? What would be the outcome of having international regimes in the South China Sea? Can the experience elsewhere be applied to the South China Sea?  相似文献   

13.
The phylogeny of the Piscicolidae was analysed from combined 18S rDNA, cytochrome c oxidase subunit I (CO-I), nicotinamide adenine dinucleotide dehydrogenase subunit I (ND-I) and morphological data using parsimony. A worldwide distribution of Piscicolidae was represented for the first time. While the family Piscicolidae was supported as a monophyletic group, the traditional subfamilies based on morphology were not supported. The Platybdellinae was polyphyletic and formed four distinct clades, and Bathybdella sawyeri did not group with any other platybdellins. The Piscicolinae was also polyphyletic, also forming four distinct clades. The pontobdellin genus Stibarobdella was shown to be the basal taxon within the Piscicolidae; however, the Pontobdellinae was found to be paraphyletic if Oxytonostoma was included. The genera Aestabdella , Austrobdella, and Malmiana were found to be paraphyletic; the genera Calliobdella, Cystobranchus, and Platybdella were found to be polyphyletic. The species Myzobdella lugubris was not found to be monophyletic. It is proposed that Oxytonostoma be transferred out of the Pontobdellinae, that Aestabdella be synonymized with Pterobdella , that Calliobdella vivida be returned to Cystobranchus , that Gonimosobdella be synonymized with Cystobranchus , and that Piscicolaria be synonymized with Myzobdella . The synonymy of Malmiana and Heptacyclus is confirmed, with Heptacyclus having priority. Piscicola milneri is confirmed to be a separate species from Piscicola geometra .  相似文献   

14.
《Ibis》1994,136(1):126-127
These are collated by Gwen Bonham, the Union's Administrative Secretary. Requests for the publication of information or other required assistance will be sympathetically considered. Publicity will gladly be given to relevant grants and awards that can be applied for, and to new societies which might be of interest to our readers. Details of conferences and meetings will also be included if sent to the Administrative Secretary at least 6 months in advance of the event. All items /or Current Notes and Notices should be sent to the BOU, c The Natural History Museum, Tring, Hertfordshire HP23 6AP, UK .  相似文献   

15.
Lapwing Vanellus vanellus is known to be declining throughout much of its UK breeding range. The ecological requirements of the species are well known and a variety of mechanisms exist which can be implemented to help recovery. Arable options within agri-environment schemes can be used to provide breeding habitat throughout the species' UK range, and targeted recovery projects have been shown to have the potential to deliver increases in breeding pairs at the local level. The farming community need to be made aware of the requirements of Lapwing if agriculture and conservation needs are to be integrated.  相似文献   

16.
When binary responses are observed over time, the dependence between observations for an individual must be considered. If the focus of a study is to identify the relationship between the binary response and a set of explanatory variables then the dependence between observations may also depend on the explanatory variables. An extension of a model where dependence is assumed to be constant will be considered. A model previously proposed for dependent binary responses will be revisited and a robust estimate of the variance-covariance matrix of coefficient estimates will be suggested to provide estimates of standard errors. The results of simulation studies investigating the properties of coefficient estimates will be discussed. An example based on a study of the AIDS epidemic and intravenous drug use behaviour will be analyzed to illustrate the techniques.  相似文献   

17.
Economic factors in the assessment of various cellulosic substances as chemical and energy resources are many and complex. No substrate nor conversion process can be singled out as significantly advantageous. Agricultural wastes appear to have the best volume and availability characteristics. If glucose is to be the end product, then it will probably have to compete with corn syrup. If SCP is to be the end product, then productivities of 2-4 g/liter-hr must be achieved and the protein demand be such that the product can sell for at least $225/ton. If alcohol is to be the end product, then an intermediate product stream of glucose and other sugars must be obtained for 1-3cent/lb of fermentable sugars.  相似文献   

18.
Shave excision is a useful technique for the treatment of superficial solar lesions. The most common of these is the solar keratosis, which can be a red or gray scaling lesion. This can at times be difficult to differentiate from the superficial basal cell carcinoma or squamous cell carcinoma or their more infiltrating types. Shave excision gives the advantage of a histopathologic report. Lesions found to be infiltrating or in danger of recurrence can then be further excised. The cosmetic appearance of the healed shave excision site is generally quite good, although it can be paler than the surrounding skin. If this is likely to be a problem, the shave graft can be applied, as with deeper shave excisions. A thin shave graft also can be used to repigment pale scarred areas. A series of 1313 shave excised lesions is analyzed.  相似文献   

19.
《Ibis》1994,136(4):517-521
These are collated by Gwen Bonham, the Union's Administrative Secretary. Requests for the publication of information and other assistance will be considered sympathetically. Publicity will be given to relevant grants and awards that can be applied for, and to new societies which might be of interest to our readers. Details of conferences and meetings will also be included if sent to the Administrative Secretary at least 6 months in advance of the event. All items for Current Notes and Notices should be sent to the BOU , % The Natural History Museum, Tring. Hertfordshire HP23 6AP, U.K. Fax No. 0442–890693 .  相似文献   

20.
Human evolution can shed light on ethics through an account of valuing. This basic human activity is to be explained as a judgement on our desires in the light of a self appraisal with respect to desires of higher order. These concern what we desire to be and how we desire to lead a life. It is argued that the conditions of valuing may be found at least in primitive form in the use of language, which surely has an evolutionary explanation. But values may be trivial or false; to be ethically correct they must be authentic and objective. Because belief and desire are plastic to cultural influence, we cannot expect an evolutionary account of this last appraisal.  相似文献   

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