弹性髓内钉和钢板固定对儿童股骨干中段骨折的疗效比较

目的:观察并比较弹性髓内钉(ESIN)与钢板固定(PF)治疗儿童股骨干中段骨折的临床疗效。方法:选择2013年2月至2016年12月我院收治的股骨干中段骨折患儿90例,依据治疗方法不同分为ESIN组和PF组。ESIN组(n=45)采用弹性髓内钉固定,PF组(n=45)采用钢板固定,比较两组患者手术时间、手术切口、术中失血量、术后切口引流量等手术指标,随访评估患者住院时间、完全负重时间、骨折愈合时间;按Flynn评定标准比较两组患者的最终治疗结果。结果:两组患者术中失血量、术后引流量比较差异无统计学意义(P0.05),ESIN组患者手术切口显著小于PF组(P0.05),手术时间、透视时间、完全负重时间均显著短于PF组(P0.05),临床疗效明显优于PF组(P0.05)。结论:与钢板固定比较,弹性髓内钉在手术时间、透视时间显著短于钢板固定,临床疗效明显优于钢板固定,可作为儿童股骨干骨折内固定的首选材料。     

Permeability properties of apical and basolateral membranes of the guinea pig caecal and colonic epithelia for short-chain fatty acids

Unidirectional fluxes of short-chain fatty acids (SCFA) indicated marked segmental differences in the permeability of apical and basolateral membranes. The aim of our study was to prove these differences in membrane permeability for a lipid-soluble substance and to understand the factors affecting these differences. Apical and basolateral membrane fractions from guinea pig caecal and colonic epithelia were isolated. Membrane compositions were determined and the permeability of membrane vesicles for the protonated SCFA was measured in a stopped-flow device. Native vesicles from apical membranes of the caecum and proximal colon have a much lower permeability than the corresponding vesicles from the basolateral membranes. For the distal colon, membrane permeabilities of native apical and basolateral vesicles are similar. In vesicles prepared from lipid extracts, the permeabilities for the protonated SCFA are negatively correlated to cholesterol content, whereas no such correlation was observed in native vesicles. Our findings confirm that the apical membrane in the caecum and proximal colon of guinea pig is an effective barrier against a rapid diffusion of small lipid-soluble substances such as SCFAH. Besides cholesterol and membrane proteins, there are further factors that contribute to this barrier property.     

骨牵引钉道周围皮温观察

目的：观察骨牵引术后钉道酒精护理的效果。方法：采用钉道周围皮温测定方法,观察30例骨牵引钉道酒精护理的住院病例每周的皮温变化,并与自身体温对照,计算出钉道周围皮温与体温的温差（△T）。结果：骨牵引术后2周时钉道周围皮温最低,骨牵引术后5周时最高。与2周时上道周围皮温比较有统计学差异（P＜0．05）。结论：骨牵引术后钉道酒精护理可出现无菌性炎症反应,相应局部皮温升高。皮温测定对预测骨牵引钉道炎症情况有一定价值。     

Expression of glucose transporter isoforms (GLUT1, GLUT2) and activities of hexokinase,pyruvate kinase,and malic enzyme in preneoplastic and neoplastic rat renal basophilic cell lesions

Sequential changes in the expression of two glucose transporter isoforms (GLUT1, GLUT2), and in the activities of hexokinase, pyruvate kinase and malic enzyme during the development of rat renal basophilic cell tumors were studied using histochemical techniques. Early basophilic cell tubules are similar to proximal convoluted tubules (PCT) in their overall histochemical pattern, particularly in the expression of glucose transporters, suggesting that basophilic cell tubules and tumors derived from them arise from PCT. In comparison with PCT, basophilic cell tubules show slightly increased activities of all the enzymes studied. In basophilic cell tumors, markedly elevated hexokinase and pyruvate kinase activities are accompanied by a considerable reduction in the expression of GLUT2. GLUT1 expression is not found in basophilic cell tubules or PCT. Small basophilic cell tumors also do not express GLUT1, but GLUT1 is regularly expressed in several cell layers surrounding necrotic areas within large basophilic cell tumors. Our results indicate that increased glycolytic activity and reduced GLUT2 expression take place during the development of renal basophilic cell tumors.     

Effect of age on NADPH-diaphorase-containing myenteric neurones of rat ileum and proximal colon

The effect of age on the distribution of NADPH-diaphorase-containing neurones was investigated in the myenteric plexus of ileum and proximal colon of embryonic day-19 rats, as well as in rats at postnatal day 4, 6 months and 26 months. The mean percentage of NADPH-diaphorase-stained neurones per ganglion was established using protein gene product 9.5 (protein found in most if not all neurones)-immunostained neurones as 100%. The results revealed that there was a significant relative increase in NADPH-diaphorase-positive neurones with increasing age in the myenteric plexus of proximal colon with nearly all protein gene product 9.5-immunoreactive neurones staining for NADPH-diaphorase in 26-month-old rats. This was in marked contrast with the ileum, where no significant relative increase in NADPH-diaphorase-positive neurones was seen in aged rats. The implications of these findings in relation to programmed cell survival and cell death are discussed.     

Transcellular Chloride Pathways in Ambystoma Proximal Tubule

The transport mechanisms of Ambystoma proximal tubule that mediate transcellular Cl⁻ absorption linked to Na⁺ were investigated in isolated perfused tubules using Cl⁻-selective and voltage-recording microelectrodes. In control solutions intracellular activity of Cl⁻ (a _i ^Cl ) is 11.3 ± 0.5 mm, the basolateral (V ₁ ), apical (V ₂ ), and transepithelial (V ₃ ) potential differences are −68 ± 1.2 mV, +62 ± 1.2 mV and −6.4 ± 0.3 mV, respectively. When Na⁺ absorption is decreased by removal of organic substrates from the lumen, a _i ^Cl falls by 1.3 ± 0.3 mm and V ₂ hyperpolarizes by +11.4 ± 1.7 mV. Subsequent removal of Na⁺ from the lumen causes a _i ^Cl to fall further by 2.3 ± 0.4 mm and V ₂ to hyperpolarize further by +15.3 ± 2.4 mV. The contribution of transporters and channels to the observed changes of a _i ^Cl was examined using ion substitutions and inhibitors. Apical Na/Cl or Na/K/2Cl symport is excluded because bumetanide, furosemide or hydrochlorothiazide have no effect on a _i ^Cl . The effects of luminal HCO⁻ ₃ removal and/or of disulfonic stilbenes argue against the presence of apical Cl-base exchange such as Cl-HCO₃ or Cl-OH. The effects of basolateral HCO⁻ ₃ removal, of basolateral Na⁺ removal and/or of disulfonic stilbenes are compatible with presence of basolateral Na-independent Cl-base exchange and Na-driven Cl-HCO₃ exchange. Several lines of evidence favor conductive Cl⁻ transport across both the apical and basolateral membrane. Addition of the chloride-channel blocker diphenylamine-2-carboxylate to the lumen or bath, increases the a _i ^Cl by 2.4 ± 0.6 mm or 2.9 ± 1.0 mm respectively. Moreover, following inhibition by DIDS of all anion exchangers in HCO⁻ ₃-free Ringer, the equilibrium potential for Cl⁻ does not differ from the membrane potential V ₂ . Finally, the logarithmic changes in a _i ^Cl in various experimental conditions correlate well with the simultaneous changes in either basolateral or apical membrane potential. These findings strongly support the presence of Cl⁻ channels at the apical and basolateral cell membranes of the proximal tubule. Received: 14 November 1997/Revised: 6 July 1998     

A freeze-fracture study of tight junctions in the pars convoluta and pars recta of the renal proximal tubule

Summary The morphology of tight junctions of the renal proximal tubule was studied comparing the pars convoluta and pars recta of rat, golden hamster, rabbit, cat, dog and tupaia. Though some interspecies variations were observed, the convoluted portions of the proximal tubules revealed quite uniformly very leaky tight junctions with mainly 1–2 strands.Along the whole proximal tubule of the rabbit kidney including the pars recta only minor differences of the zonulae occludentes were found. By contrast, the tight junctions of the pars recta in other species were much more elaborate, especially in cat and tupaia, having up to 6 strands and an overall depth of more than 150 nm. The implications of these findings are discussed with special regard to the functional differences between the pars convoluta and pars recta of the proximal tubule.This work was supported by the Deutsche Forschungsgemeinschaft     

Na+-stimulated ATPase activities in kidney basal-lateral plasma membranes

In the present work we demonstrate the existence of a Na⁺-stimulateo, Mg²⁺-dependent ATPase activity, which is insensitive to ouabain, and which is 100% inhibited by 1.5 mM ethacrynic acid in freshly prepared, basal-lateral enriched, plasma-membrane fractions obtained from guinea-pig kidney cortex slices (which are mainly made up by proximal tubules). This ATPase activity has characteristics similar to those described previously in a microsomal fraction of the guinea-pig kidney cortex by a procedure which required ageing of the preparation for more than two weeks (Proverbio, F., Condrescu-Guidi, M. and Whittembury, G. (1975) Biochim. Biophys. Acta 394, 281–292), it does not seem to be due to some partially modified activity of the Mg²⁺-ATPase, the (Na⁺ + K⁺)-or the Ca²⁺-ATPase activities present in this tissue. It seems to be due to the activity of another system, which is located on the basal-lateral membrane of the kidney tubular cells.     

Fixion PF和PFN治疗老年骨质疏松股骨转子间骨折的临床效果比较

目的:比较可膨胀髓内钉(Fixion PF)与股骨近端髓内钉(PFN)联合双磷酸盐治疗老年骨质疏松股骨转子周围骨折临床效果及安全性。方法:选择我院收治的47例老年骨质疏松股骨转子间骨折患者并将其随机分为两组:对照组应用PFN治疗,观察组应用Fixion PF治疗,术后两组患者均接受双磷酸盐抗骨质疏松治疗,比较两组的Harris评分、骨折愈合时间、手术时间、术中出血、切口长度、术后严重并发症的发生情况。结果:两组的Harris评分、骨折平均愈合时间以及严重并发症的发生率比较均无统计学差异(P均0.05),但Fixion PF组的手术时间较PFN组显著缩短,术中出血明显减少,切口长度显著下降,差异均有统计学意义(P0.05)。结论:Fixion PF联合双磷酸盐抗骨质疏松治疗对老年骨质疏松股骨转子间骨折的临床效果优于PFN联合双磷酸盐抗骨质疏松治疗。     

Normal masticatory function partially protects the rat mandibular bone from estrogen-deficiency induced osteoporosis

Background/aim

In a previous study we showed that mandibular alveolar (trabecular) bone appears to be less sensitive to estrogen deficiency than the proximal tibia spongiosa. We hypothesized that the mechanical loading of the alveolar process during mastication may protect the alveolar bone from the detrimental effects observed in other skeletal sites. To test this hypothesis we compared the effect of ovariectomy on the mandibular alveolar bone and the proximal tibia spongiosa of rats fed either a normal (hard) or a soft diet.

Methods

Forty six-month-old female Sprague–Dawley rats underwent trans-abdominal ovariectomy (OVX) or sham operation (SHAM). Half of the animals received their food in the usual form of pellets (hard consistency), while the other half received a soft, porridge-like, isocaloric diet of identical composition (soft consistency). Micro-computed tomographic histomorphometry was used to evaluate the trabecular micro-architecture. A two-factor analysis of variance was used to test for effects and interaction of ovariectomy and/or soft diet.

Results

OVX had a significantly negative effect on the proximal tibia spongiosa (all parameters under study except trabecular thickness; p<0.001) and on the mandibular alveolar bone (trabecular number and spacing; p<0.05). Soft diet led to a further decrease of mandibular BV/TV (p<0.01), trabecular thickness (p<0.05) and number (p<0.05), as well as increase of separation (p<0.001). A significant interaction was observed between OVX and soft diet concerning the mandibular BV/TV, as well as trabecular thickness and spacing (p<0.05).

Conclusion

Normal (hard) diet limited significantly the negative effects of estrogen deficiency on mandibular alveolar bone micro-architecture four months after ovariectomy.