人工股骨头置换术与股骨近端防旋髓内钉内固定治疗老年股骨转子间骨折患者的疗效比较研究

目的:探讨人工股骨头置换术(AFHR)与股骨近端防旋髓内钉(PFNA)内固定治疗老年股骨转子间骨折(IFF)患者的疗效。方法:选择2010年3月至2016年8月本院收治的老年IFF患者102例为研究对象,采用随机数字表法分为AFHR组(n=51)和PFNA组(n=51),比较两组手术一般情况(包括手术时间、术中出血量、下地活动时间、完全负重时间、术后住院时间),术前与术后第3、6、12个月采用Harris评分量表对患者进行髋关节功能评分,观察术后病死率及并发症的发生情况。结果:PFNA组手术时间、术中出血量少于AFHR组,下地活动时间、完全负重时间多于AFHR组,差异有统计学意义(P0.05),两组术后住院时间比较差异无统计学意义(P0.05)。两组患者术前、术后6个月、术后12个月Harris评分比较差异无统计学意义(P0.05),术后3个月AFHR组患者Harris评分高于PFNA组,且两组患者术后Harris评分较治疗前均升高,差异有统计学意义(P0.05)。PFNA组病死率和并发症发生率分别为0.00%和5.88%,与AFHR组的1.96%和9.80%比较,差异无统计学意义(P0.05)。结论:在老年IFF的手术治疗中,PFNA内固定具有手术时间短、术中出血量少的优势,AFHR后患者可早期进行功能锻炼,术后髋关节功能恢复快。     

Kinetics of the removal of ferric ion from transferrin by aminoalkylphosphonic acids

The kinetics of ion removal at 25 degrees C in 0.1 M Tris, pH 7.4 by a series of phosphonic acids have been evaluated. The initial rate of iron removal is first order in ferric-transferrin, but shows a hyperbolic dependence on the concentration of the phosphonate ligand. At high ligand concentrations the reaction is clearly biphasic, and the data are interpreted in terms of nonequivalent rate constants for iron removal from the two transferrin iron-binding sites. Rate constants for three phosphonic acid ligands are approximately 0.025 min-1 and approximately 0.007 min-1 for the faster and slower binding sites. The results are discussed in relation to the conformational change mechanism for iron removal from transferrin proposed by Coward et al. [21].     

Mg2+ adenosine triphosphatase from cell envelopes of free-living and bacteroid forms of Rhizobium lupini strain NZP2257

A procedure for the purification of Mg2+ adenosine triphosphatase (EC 3.6.1.3) from free-living and bacteroid forms of Rhizobium lupini NZP2257 is described. The enzyme was released from cell envelopes using Triton X-100 and purified by gel filtration on Ultrogel AcA 22, followed by preparative gel electrophoresis on agarose. The purified ATPase had a molecular weight of about 355,000, as determined from sedimentation coefficients on sucrose gradients. Kinetic analysis of activity of the enzyme from free-living R. lupini showed it to be typical of F1-type Mg2+ ATPases from bacteria. Mg stimulated activity at pH 7.0, although, when present as the free ion, Mg caused non-competitive inhibition (K1 = 1.5 mM). Maximum activity with ATP occurred over a broad pH range from 6.0 to 10.5. ATP, GTP, and UTP, and, to a much lesser degree, CTP and ADP, were hydrolyzed by the enzyme. Hydrolysis of glucose 6-phosphate was not observed. The Km for ATP at pH 7.0 was 0.67 and for GTP 1.4 mM. ATPase activity was inhibited by ADP, and competitive with ATP (KI = 0.18 mM). Azide also caused inhibition but fluoride and DCCD had no effect. Native and sodium dodecyl sulfate-gel electrophoretic analysis revealed no obvious differences between ATPases from free-living and bacteroid forms of R. lupini.     

Synthesis and separation of tritium-labeled intermediates of the shikimate pathway

[5-³H]Shikimate (sp radioact 2000 Ci/mol) has been synthesized by reduction of the methyl ester of 5-dehydroshikimate with NaB³H₄ and subsequent hydrolysis of the ester group (M. M. Leduc, P. M. Dansette, and R. G. Azerad (1970) Eur. J. Biochem.15, 428–435). The [5-³H]shikimate has been converted enzymatically to [5-³H]chorismate and [5-³H]prephenate of similar high specific radioactivity by using a cell-free extract of Aerobacter aerogenes 62-1. In addition, a chromatograhic procedure, which utilizes polyethyleneimine-cellulose thin-layer chromatograms, has been developed for the separation of intermediates along the shikimate pathway between shikimate and hydroxyphenylpyruvate or phenylpyruvate. Since the method allows quantitative measurement of tritium-labeled intermediates, it provides the basis for sensitive radioassays of the individual enzymes and allows study of the reaction flux along the overall pathway. The same intermediates can be separated on a large scale by use of a column of DEAE-Sephacel.     

Host defense in cryptococcosis. II. Cryptococcosis in the nude mouse.

In the homozygous state, mice carrying the “nude” (nu) gene are hairless (nude), lack a thymus and have profound deficiency of cell-mediated immunity. Cryptococcosis was studied in BALB/c and Swiss mice, each strain carrying the nu gene. The purpose was to determine the interactions of the nu gene and mouse strain in terms of susceptibility to Cryptococcosis. Mice of both strains could be sensitized to produce delayed-type hypersensitivity reactions to cryptococcal extract in the heterozygous nu/X state, but not in the nu/nu state. Nu/X Swiss mice were more resistant than nu/X BALB/c mice to infection with a highly virulent strain (B) of Cryptococcus neoformans. However, nu/nu BALB/c and nu/nu Swiss mice were both highly susceptible to the same microorganism. Challenge with another cryptococcal strain (A) of much lower virulence for nu/X mice killed 100% of BALB/c and Swiss nu/nu mice. These studies indicate that thymus-dependent immune functions are critical determinants of host resistance to murine Cryptococcosis.     

An examination of the forms of scatchard plots of binding results outside domains of sigmoidality

General expressions are formulated for the first and second derivatives of the Scatchard function, r/[S], with respect to the binding function, r, from an equation that describes the binding of a ligand to a two-state acceptor system (either isomerizing or polymerizing). The expressions are utilized to determine the sign of the second derivative for particular systems under conditions where the first derivative is negative for all r. The work therefore correlates with previous studies, which stressed conditions of existence of critical points in Scatchard plots, by examining more fully possible forms of binding curves outside such domains of sigmoidality. Particular attention is given to the condition, d(r/[S])/dr < 0 and d²(r/[S])/dr² > 0 for all r (which defines a Scatchard plot convex to the r-axis). In agreement with previous findings it is proven that the isomerizing acceptor model cannot give rise to this form of plot and is therefore distinguished from negatively co-operative allosteric models. On the other hand, the polymerizing acceptor model may yield such a Scatchard plot, a feature demonstrated by formulating explicit conditions for its manifestation when ligand binding is exclusive to the polymeric state, and illustrated numerically for a system in which ligand binds to both oligomeric states. Distinction between such systems and those exhibiting negative co-operativity is possible on the basis of the Scatchard plots, which exhibit dependence on acceptor concentration in the case of a polymerizing acceptor; indeed, an example is provided where variation of acceptor concentration for a system characterized by fixed interaction parameters effects a conversion from sigmoidal binding behaviour to that typified by a Scatchard plot convex to the r-axis.     

Transhumanism and moral equality

Conservative thinkers such as Francis Fukuyama have produced a battery of objections to the transhumanist project of fundamentally enhancing human capacities. This article examines one of these objections, namely that by allowing some to greatly extend their capacities, we will undermine the fundamental moral equality of human beings. I argue that this objection is groundless: once we understand the basis for human equality, it is clear that anyone who now has sufficient capacities to count as a person from the moral point of view will continue to count as one even if others are fundamentally enhanced; and it is mistaken to think that a creature which had even far greater capacities than an unenhanced human being should count as more than an equal from the moral point of view.     

Survival lotteries reconsidered

In 1975 John Harris envisaged a survival lottery to redistribute organs from one to a greater number in order to reduce number of deaths as a consequence of organ failure. In this paper I reach a conclusion about when running a survival lottery is permissible by looking at the reason prospective participants have for allowing the procedure from a contractual perspective. I identify three versions of the survival lottery. In a National Lottery, everyone within a jurisdiction is a candidate for being a donor for everyone else, disregarding all differences between individuals' eventual possibility of needing an organ. In a Group Specific Lottery, it is a question of running a lottery among members of a specific group who share the same probability of getting organ failure. In a Local Lottery one randomises among individuals who are already in need of a new organ but who happen to be compatible and in need of different organs. While the first is vulnerable to considerations of fairness, it is difficult to perceive a feasible way to implement the second option that does not come with a host of unwelcome consequences. I argue, however, that it is permissible to run Local Lotteries.     

Two children of empire: Michael Banton and John Rex

This paper argues that both Michael Banton and John Rex were ‘children of empire’, albeit in starkly different ways, and that these differences were at the core of their querulous exchanges over their long careers. The larger issue, however, concerns the impact of colonialism on sociology, especially in its formative years, and conversely, the role of sociology in providing erudite justification for colonialism.     

Transverse (Harris) lines in irish archaeological remains

Transverse lines were examined in 633 long bones from 73 individuals exhumed from two burial sites in the Republic of Ireland: Waterford City and Tintern Abbey. The burials cover four distinct periods between the 11th and 17th centuries. Lines were most numerous in the tibia, especially in the distal segment, and were not seen in the humerus nor the proximal part of the femur. The number of lines varied between the proximal and distal segments of each long bone, and though apparently equal in number across the midline, there were significant differences in the incidence of lines between corresponding pairs of bones. Thus, it is unwise to rely on the results of a single bone or one type of long bone alone either to indicate the health status of an individual, or as the basis for assessing the health status of a small population. Such results should be used only in association with other indicators. © 1996 Wiley-Liss, Inc.