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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   
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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   
5.
Spectral imaging fluorescence microscopy   总被引:2,自引:0,他引:2  
The spectral resolution of fluorescence microscope images in living cells is achieved by using a confocal laser scanning microscope equipped with grating optics. This capability of temporal and spectral resolution is especially useful for detecting spectral changes of a fluorescent dye; for example, those associated with fluorescence resonance energy transfer (FRET). Using the spectral imaging fluorescence microscope system, it is also possible to resolve emitted signals from fluorescent dyes that have spectra largely overlapping with each other, such as fluorescein isothiocyanate (FITC) and green fluorescent protein (GFP).  相似文献   
6.
In the 11‐residue long dark‐color‐inducing neurohormone (DCIN = [His7]‐corazonin), of locusts, from residue 2 to residue 11, one amino acid at each time was substituted by d ‐phenylalanine (d ‐Phe). The dark‐color‐inducing effect of these peptides was investigated in comparison with unaltered DCIN by a bioassay based on nymphs of a DCIN‐deficient albino mutant of the migratory locust, Locusta migratoria. Substitution of any single amino acid by d ‐Phe always reduced the activity, but did not abolish it completely. Maximum inactivation was obtained after substitution of Gln4, Ser6, or Trp9. The latter two residues are within the partial sequence ‐Ser‐Xxx‐Gly‐Trp‐ (Xxx = His in the DCIN) that seems to be important for the dark‐color‐inducing activity, as found also in another study (Insect Biochem. Mol. Biol. 32, 2002, 909). Gln4, however, is outside of this partial sequence. Minimal, although still considerable, inactivation occurred after substitution of Gly8, Phe3, or Asn11, despite the fact that Gly8 is within the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence. In conclusion, no single active core was found, indicating that the whole sequence of the DCIN is necessary to induce maximum darkening effect. No difference was found in the activity of the peptides in which Gly8 was substituted by d ‐Phe or by L ‐Phe. Therefore the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence does not seem to be stabilized by a type II β‐turn. Nevertheless, existence of another kind of turn that includes this partial sequence is feasible. A single unsuccessful attempt was made to discover an antagonist to the DCIN.  相似文献   
7.
新型药物开发制备过程中,需要对药物颗粒进行粒子设计,通过多层微胶囊化而得到复合包覆药物颗粒。药物包覆、微胶囊制备方法很多,可分为化学法、物理化学法、物理法。本文着重介绍了制备复合多层包覆药物颗粒的几种物理机械方法:复合杂化系统,高速椭圆转子混合法、喷流床包覆法。简要分析了该技术用于中药现代化加工的可能性。  相似文献   
8.
微细药物表面包覆技术在制剂中的应用   总被引:1,自引:0,他引:1       下载免费PDF全文
新型药物开发制备过程中,需要对药物颗粒进行粒子设计,通过多层微胶囊化而得到复合包覆药物颗粒。药物包覆、微胶囊制备方法很多,可分为化学法、物理化学法、物理法。本文着重介绍了制备复合多层包覆药物颗粒的几种物理机械方法:复合杂化系统,高速椭圆转子混合法、喷流床包覆法。简要分析了该技术用于中药现代化加工的可能性。  相似文献   
9.
BackgroundSudden cardiac death is a major public health problem. Epidemiological and clinical differences according to gender have been described in sudden cardiac death. The aim of this study was to examine the gender differences between autopsy findings and circumstance of occurrence associated with sudden cardiac death.MethodsWe prospectively collected epidemiological and autopsy data of victims of sudden cardiac death occurring in the northern governorates of Tunisia between January 2013 and December 2019. Symptoms preceding death, circadian, weekly and seasonal variations of sudden death were also analyzed.ResultsThe study population included 1834 men and 468 women with a mean age of 56.5 ± 14.2 years. All cardiovascular risk factors except smoking were significantly more frequent among women but ischemic heart disease was the most common cause of death in men (51.3 %, versus 28 %, P < 0.001). Women were more likely to have a negative macroscopic autopsy than men (34 % versus 23.6 %, P < 0.001). Chest pain preceding sudden death was more frequent in male (24 % versus 13.2 %, P < 0.001). In contrast, women were more likely to have dyspnea (8.1 % versus 15.6 %, P < 0.001). Sudden death in women occurred indoors more often than in men (63.9 % versus 54.5 %, P < 0.001) and also more often during night (midnight to 6 am). We also recorded an excess cardiac mortality in winter in both sexes.ConclusionsWomen had considerably more cardiovascular risk factors and more commonly negative macroscopic autopsy. Death occurred indoors and during night more often than in men.  相似文献   
10.
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