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91.
Engineered skin substitutes are widely used in skin wound management. However, no currently available products satisfy all the criteria of usability in emergency situations, easy handling, and minimal scar formation. To overcome these shortcomings, we designed a cell‐free bandage‐type artificial skin, named “VitriBand” (VB), using adhesive film dressing, silicone‐coated polyethylene terephthalate film, and collagen xerogel membrane defined as a dried collagen vitrigel membrane without free water. We analyzed its advantages over in‐line products by comparing VB with hydrocolloid dressing and collagen sponge. For evaluation, mice inflicted with full‐thickness skin defects were treated with VB, hydrocolloid dressing, and collagen sponge. A plastic film group treated only with adhesive film dressing and silicone‐coated polyethylene terephthalate film, and a no treatment group were also compared. VB promoted epithelization while inhibiting the emergence of myofibroblasts and inflammation in the regenerating tissue more effectively than the plastic film, hydrocolloid dressing, and collagen sponge products. We have succeeded in establishing a cell‐free bandage‐type artificial skin that could serve as a promising first‐line medical biomaterial for emergency treatment of skin injuries in various medical situations.  相似文献   
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The effects of transjugular intrahepatic portosystemic shunt (TIPS) placement on esophageal motor function and gastroesophageal reflux were investigated in patients with esophageal varices. In six men with esophageal varices, esophageal manometry and upper gastrointestinal endoscopy were performed before and 15–20 days after TIPS placement. Intraesophageal pH monitoring was performed in the four patients with severe esophageal varices (defined as the largest sized varices) following TIPS placement. Findings were compared with those in six healthy men (controls) who underwent esophageal manometry and intraesophageal pH monitoring. The esophageal varices resolved or were reduced after TIPS placement. Resting lower esophageal sphincter (LES) pressures were similar in the study group before and after TIPS placement and in the control subjects. The incidence and progression of esophageal contractions were similar in the study group before and after TIPS placement and in the control subjects. At 3 cm above the LES, the amplitude of esophageal contraction after TIPS placement was significantly higher than that before TIPS placement. At 3 and 8 cm above the LES, the amplitude of esophageal contraction in the control subjects was significantly higher than that in the study group before and after TIPS placement. Esophageal acid exposure time after TIPS placement was similar to that in the controls. TIPS placement is a useful treatment that improves esophageal motor function without the occurrence of pathologic gastroesophageal reflux. (Received May 28, 1997; accepted Sept. 26, 1997)  相似文献   
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Background

Lipid transfer protein (LTP) is a major fruit allergen. It has, however, recently been revealed that the systemic reaction in peach-allergic patients is related not only to LTP (Pru p 3) but also to gibberellin-regulated protein (Pru p 7). We investigated recombinant Pru p 7 (rPru p 7) for its potential use in worldwide standardization for the diagnosis of peach allergy.

Methods

Natural Pru p 7 (nPru p 7) was purified from peach crude extract using a monoclonal antibody affinity column. Complementary DNA for Pru p 7 was cloned and expressed in Escherichia coli and Pichia pastoris. Serum immunoglobulin (Ig) E in peach-allergic patients was examined by enzyme-linked immunosorbent assay (ELISA) using nPru p 7 and rPru p 7 (E. coli product: erPru p 7 and P. pastoris product: prPru p 7).

Results

Peach-allergic patients (n = 27) were diagnosed and categorized into oral reaction (n = 10) or systemic reaction (n = 17). The nPru p 7 positivity based on serum IgE levels was 52% in the systemic-reaction group and 0% in the oral-reaction group (P < 0.05). In the systemic-reaction group, there was no significant difference in reactivity between nPru p 7 and prPru p 7, but the reactivity of erPru p 7 was significantly lower than those of nPru p 7 and prPru p 7 (P < 0.05).

Conclusions

We found that prPru p 7 exhibited reactivity in ELISA comparable to that of nPru p 7 for the diagnosis of peach allergy with systemic reaction.  相似文献   
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AIM: To develop a Home Care Quality Assessment Index (HCQAI) that may be used for overall assessment of home care in three areas: 1) conditions of the impaired elderly (outcome); 2) caregiver and caregiving situation (process); and 3) the home care environment (input). METHODS: To develop the HCQAI, a list of items for assessment was drawn up, and the reliability of each item was verified. Reliability was investigated by a) test-retest reliability, and b) inter-rater reliability. Impaired elderly and their family caregivers who used the visiting nurse station of the Okazaki Medical Association were surveyed. A kappa coefficient of 0.4 or greater generally served as the inclusion criteria for test-retest and inter-rater reliability of each item. A factor analysis was conducted for items satisfying the above criteria, using 10 scales. RESULTS: Cronbach's alpha showing internal consistency (reliability) for these scales was 0.6-0.9. Two scales corresponded to care within the home: the "barrier-free" and "improvement of water facilities"; three to the caregiver situation: "dressing appropriate for the season," "mistreatment by the elderly," and "hygiene and assistance"; and five involved conditions of the impaired elderly: "cognition," "paralysis," "vision and hearing," "ADL," and "gross motor." CONCLUSION: The HCQAI developed in the present study, consisting of 41 items, can assess quality of home care both objectively and comprehensively, based on professional staff observation. Few indexes of this kind exist worldwide to scientifically assess input, process and outcome in the delivery of quality home care for the impaired elderly.  相似文献   
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Objectives: The success rate of dental implants depends on the type of bone at the implant site. The purpose of the present study was to investigate the effects of the bone parameters at the implant-placement site on peri-implant bone strain distributions. Study Design: The morphologies and bone densities of seventy-five potential implant sites in the posterior mandible were measured using computed tomography (CT). Based on the CT data, we defined bone parameters (low and high in terms of cancellous-bone density and crestal-cortical bone density, and thin and thick in terms of crestal-cortical bone thickness), and we constructed finite-element models simulating the various bone types. A buccolingual oblique load of 200 N was applied to the top of the abutment. The von Mises equivalent (EQV) strains in the crestal-cortical bone and in the cancellous bone around the implant were calculated. Results: Cancellous-bone density greatly affected the maximum EQV strain regardless of the density and thickness of the crestal cortical-bone. The maximum EQV strains in the crestal cortical-bone and the cancellous bone in the low-density cancellous-bone models (of 150 Hounsfield units (HU) were 1.56 to 2.62-fold and 3.49 to 5.31-fold higher than those in the high-density cancellous-bone models (of 850 HU), respectively. The crestal cortical-bone density affected the maximum EQV strains in the crestal cortical-bone and in the cancellous bone in the low-density cancellous-bone models. The crestal cortical-bone thickness affected the maximum EQV strains in the cancellous bone and in the crestal cortical-bone in the low-density cancellous-bone models. Conclusions: Our results confirm the importance of bone types for the peri-implant bone strain distribution. Cancellous-bone density may be a critical factor for peri-implant bone strain. Key words:Dental implant, bone density, finite-element analysis.  相似文献   
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