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1.
A novel retractor has been designed to achieve atraumatic retraction of the liver and displacement of hollow viscera during endoscopic surgery. The functional section of the instrument, when locked, forms a silicon-covered uniplanar hook which can be deployed for horizontal lift of solid organs such as the liver or be used to engage bowel for displacement from the operative field. Following laboratory testing, the instrument has been evaluated clinically and its ease of deployment and atraumatic nature have been confirmed. It has been found to be particularly effective for elevation of the thick fatty left lobe of the liver during antireflux surgery.  相似文献   
2.
A technique for laparoscopic reduction, crural repair, and total fundoplication for large symptomatic hiatal hernia is described. The procedure entails the mobilization of the esophagogastric junction with crural repair by a continuous suture technique employing a special pre-formed jamming loop knot, followed by total fundoplication that is fixed proximally to the anterior margin of the diaphragmatic hiatus and distally to the esophagogastric junction. The procedure has been performed in eight elderly patients with a good outcome and accelerated recovery to full activity.  相似文献   
3.
The health-related behaviours of a random sample (n=92) of Hong Kong nurses were assessed by a questionnaire written either in English or in English and Chinese. Hong Kong nurse reported negligible smoking or a alcohol use, low levels of breast self-examination, cervical screening behaviour and regular exercising, seat belt use and driving within the speed limit. The sample reported high levels of making efforts to avoid foods high in cholesterol, eating foods high in fibre and eating fruit daily. Dental hygiene was reported to be high. Just over half the sample reported sleeping 7–8 hours each night and eating breakfast daily. Most nurse reported maintaining their body weight at a healthy level and eating snacks between meals. The English language version of the questionnaire produced a slightly better response rate than the bilingual questionnaires. The results are discussed with reference to previous studies of females' health-related behaviours in Hong Kong and elsewhere. The implications for Hong Kong nurses' role in health promotion is discussed.  相似文献   
4.
The hexane extract from Nutmeg, the seed ofMyristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by SiO2 column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B(II) and dehydrodiisoeugenol(III) were isolated as active principles. Compounds II and III, with a single treatment (200 mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they posses CNS-depressant properties.  相似文献   
5.
We report, for the first time, the light microscopical and ultrastructural appearance of ZnT3-immunoreactivities in the ependymal cells of the central canal of the mouse spinal cord. Light microscopy revealed the presence of ZnT3-immunoreactive (Ir) ependymal cells in 1 microm thick epon sections stained by the ABC method. The ZnT3-Ir cells were observed at all levels of the spinal cord, but were a little more numerous in lumbosacral segments than in cervicothoracic segments. The ZnT3-Ir cells had large, ovoid nuclei with abundant cytoplasm, and protruded into the lumen of the central canal. Our ultrastructural findings suggest that the ZnT3-Ir ependymal cells possess secretory activity directed towards the central canal. We propose that they may play a role in the trans-ependymal mechanism responsible for zinc homeostasis between cerebrospinal fluid and the central area of the gray matter.  相似文献   
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7.
Heat-shock induces a strong stress response and modifies all aspects of cellular physiology, which involves dynamic changes in the nucleocytoplasmic distributions of a variety of proteins. Many distinct nucleocytoplasmic transport pathways exist in eukaryotic cells, but how a particular transport pathway is regulated under different cellular conditions remains elusive. The finding of this study indicate that conventional nuclear import, which is mediated by importin alpha/beta, is down-regulated, while the nuclear import of 70 kD heat-shock cognate protein is up-regulated in heat-shock cells. Among the factors involved in the mediation of the conventional nuclear import, significant levels of importin alpha accumulate in the nucleus in response to heat-shock. An analysis of the behaviour of importin alpha with fluorescence recovery after photobleaching and fluorescence loss in photobleaching studies show that nuclear importin alpha becomes less mobile and its nucleocytoplasmic recycling is impaired in heat-shock cells. These data coincided well with biochemical and cytological studies. Our present data show that heat-shock induces the nuclear accumulation, nuclear retention, and recycling inhibition of importin alpha, resulting in the suppression of conventional nuclear import. This suggests a new regulatory mechanism for the adaptation of cells to environmental changes, such as heat-shock.  相似文献   
8.
The resolving powers of the enforced smoothing and log-normal parametric estimation techniques in recovering ventilation/perfusion ratio distributions were evaluated using noisy inert gas elimination data simulated from hypothetical distribution functions representing various degrees of heterogeneity. The resolving powers were assessed in terms of the statistical recoverabilities of the shunt, dead space, modality, and modal moments characterizing the perfusion distribution. For all distributions tested, both modal mean and shunt were estimated by either technique with sufficient accuracies. Modal dispersions (σ) were consistently overestimated by up to 0.15 decade for narrow distributions, but the mean errors became negligible for σ greater than 0.2 decade. As compared with the shunt, the dead space estimates were more variable and biased, probably due to their indirect estimation from the perfusion distribution, which was imperfectly recovered. Both broad unimodal and widely separated bimodal or trimodal distributions (σ>0.6 decade) were recovered as bimodal distributions of similar forms, so that detection of modality was difficult. The recoveries by both techniques were comparable in most cases studied, except that parametric estimation generally tended to be more sensitive to measurement errors and was computationally less efficient. These results provide a useful basis for the interpretation of distributions obtained from empirical inert gas data.  相似文献   
9.
Summary Hyperhomocysteinemia has been reported as an independent risk factor for atherosclerotic cerebrovascular and coronary heart diseases. 5,10-Methylenetetrahydrofolate reductase (MTHFR) is one of the enzymes responsible for hyperhomocysteinemia. The C to T transition of the MTHFR gene at nucleotide position 677 results in decreasing the enzymatic activity and increasing the plasma homocysteine level. We studied the distribution of the MTHFR gene mutation among the Japanese population. The subjects were 129 Japanese males (aged 40–59 years). The allele frequency of the mutation was 0.38. The frequencies of the three genotypes were as follows: +/+, 11%; +/–, 54%; –/–, 35% (+ and – indicate the presence and absence of the mutation, respectively). We also studied the frequency of the MTHFR gene mutation in the middle-aged Japanese males with hypertension to investigate the possibility that this mutation is related to essential hypertension. The normotensive and hypertensive subjects were identical in the distribution of the mutated allele and the frequencies of the three genotypes. Furthermore, the prevalence of hypertension in each genotype group was same, although the mean diastolic pressure of the group with homozygous mutation was significantly higher than that of other groups (p<0.05).  相似文献   
10.
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