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1.
Effect of modified atmosphere packaging on the shelf-life of coated, whole and sliced mushrooms 总被引:2,自引:0,他引:2
Whole and sliced fresh mushrooms (Agaricus bisporus) were packaged with PVC wrap or two polyolefins (PD-941 and PD-961) films after coating with CaCl2 and chitosan. Package gas composition, color, weight loss and maturity were measured during storage at 12 °C and 80%RH. For PD-961, the highest in-package concentration occurred during the first day of storage regardless of treatments, while wrap and PD-941 showed varying degrees in-package concentration with different processes and coatings. The whiteness of whole mushrooms varied significantly with the type of coating, but not with the type of films. The extent of darkening was greater in coated whole mushrooms than in sliced ones. Weight loss occurred in all packages and varied from 3 (g/100 g) to about 7 (g/100 g) after 6 days of storage. Due to a lower permeability, PD-961 packages had the lowest weight loss. The type of packaging films significantly affected the maturity index, where PD-961 most effectively lowered maturity index for both whole and sliced mushrooms, thus extending the shelf-life. The type of coating did not appear to affect maturity index except for the wrap package where chitosan coating markedly lowered the maturity index of sliced mushrooms. 相似文献
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DA O'Farrell HM Ridha P Keenan FW McManus M Stephens 《Canadian Metallurgical Quarterly》1997,28(5-6):377-379
Roller blading is a new and increasingly popular leisure activity in many countries. We reviewed 110 consecutive patients with roller-blade injuries between 1 January and 30 June 1996. The patients ranged from 4 to 14 years in age (mean 6.5 years). Eighty-three (75.4%) sustained injuries to the upper limb and 27 (24.5%) injured the lower limb. Fifty-six patients, were girls and 54 were boys. Of the 110 patients, 79 (72.7%) sustained fractures, 28 (25.4%) soft tissue injuries and 3 (2.7%) dislocations. Eighty-three (75.4%) of the patients wore no protective equipment on the limbs. Four months following injury 103 (93.6%) patients were fully recovered. The mean duration of school absence was 3 days. Subsequently 101 children returned to using roller-blades following injury. Seventy-three (66.3%) of these now use protective equipment. We found that injuries were unrelated to age or duration of roller-blading experience or to the brand-name of roller blades used, and that most of our patients wore no protective equipment at the time of injury. 相似文献
4.
Hadjem A. Lautru D. Dale C. Man Fai Wong Hanna V.F. Wiart J. 《Microwave Theory and Techniques》2005,53(1):4-11
This paper gives a first comparison of specific absorption rate (SAR) induced in a child-sized (CS) head and an adult head using a dual-band mobile phone. In the second study, the visible human head is considered and comparison of SAR induced in a CS or child-like (CL) head and an adult head using a dual-band mobile phone is given. All the peaks of average SAR over a mass of 10 and 1 g in the head and the power budget are determined in the two comparisons using the finite-difference time-domain method. The differences between the results for adult and CS or CL heads are given at 900 and 1800 MHz. No important differences are noted for the peak SAR averaged over 10 g (SAR10 g), between the two adult head models, as well as between the two child head models. The peak SAR10 g in the brain of the CS or CL head is slightly more significant than that for the adult one. 相似文献
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The data presented here are part of an on-going longitudinal study of the relationship between socioeconomic status and mortality in the major metropolitan centers of Ohio. Using a Standardized Mortality Ratio, we find that mortality in the seven-city urban aggregate exceeds that of the rest of the state by 39 per cent for the nonwhite population and only 1 per cent for the white population. Further, for the nonwhite population, living in a high income area has no discernible health benefit for nonwhites as compared to whites. On the other hand, for the AIDS virus, there is a clear inverse association between economic status and mortality from AIDS. It is clear that the interrelationship among race, economic status, and health continues to be a complex one on which further research is needed. 相似文献
7.
C Müller H Dienemann H Hoffmann H Berger M Storck A Jolk FW Schildberg 《Canadian Metallurgical Quarterly》1993,118(9):543-548
The treatment of tracheo-bronchial stenosis or tracheomalacia is mainly carried out by means of resection or tracheoplastic operative strategies. Since the introduction of metal-mesh stents, a definitive endoluminal therapy has to be considered under new aspects. Six patients with malignant stenosis or tracheomalacia due to compression were treated by implantation of Palmaz- or Wallstents. Immediately after the implantation, patients were relieved from dyspnoea, the forced inspiratory volume-1 (FIV1) was normalized. All implanted stents were well tolerated, even in the long-time follow-up (19 months). Bronchoscopic control showed overgrowth of the metal meshes by respiratory epithelium. The implantation of metal-mesh stents is an adequate alternative in the treatment of malignant stenosis and tracheomalacia. 相似文献
8.
G Berding H Schliephake G Neumann R Schmelzeisen FW Neukam GJ Meyer KF Gratz H Hundeshagen 《Canadian Metallurgical Quarterly》1996,35(5):156-163
AIM: The aim of this study was early differentiation between uncomplicated and complicated processes of healing in the jaw using bone SPECT. METHODS: Investigations were performed in 40 mandibular fractures and 26 jaws after onlay osteoplasty as well as secondary insertion of implants. Bone SPECT was carried out within 1-2 months and after approximately 4-5 months. The uptake in the jaw was assessed semi-quantitatively using ROI analysis. RESULTS: Fractures with uncomplicated healing showed a decrease of uptake in follow-up, whereas fractures with an infection in the later course showed an increase, resulting in a significantly higher uptake at the follow-up investigation for the latter group. 1-2 months after onlay osteoplasty significantly lower uptake was found in regions with later occurrence of sequestration. In regions with implants in which osseointegration failed, there was significant reduction of uptake initially and significant elevation at the follow-up investigation. CONCLUSION: These results indicate a prognostic relevance of bone SPECT in the evaluation of processes of healing in the jaw. 相似文献
9.
The present study assesses the endocrinological, endometrial histology and vaginal ultrasound profiles of nomegestrol acetate subdermal implant users at varying times after insertion. Follicle stimulatory hormone, luteinizing hormone, oestradiol, progesterone, vaginal ultrasound assessment of the ovaries and the histological dating of the endometrium were serially assessed for a period of 50 days immediately after the insertion, and after at 6 months and 12 months of use. The endocrinological results of this prospective observational clinical trial indicated that 75% of the cycles across the study period in Uniplant users were anovulatory, 63% showing development of a persistent non-luteinized follicle. Anovulatory cycles devoid of follicular development were seen primarily in the first months after Uniplant insertion. Ovulatory cycles represented 25% of the Uniplant cycles. Inadequate luteal phase or disregulation of follicular growth was a common feature of ovulatory cycles. In conclusion, these findings suggest that the contraceptive mechanisms of a single nomegestrol acetate subdermal implant involve prevention of follicular growth, development of a persistent non-luteinized follicle, inadequate luteal phase and disruption of the endometrial architecture. 相似文献
10.
This paper reviews the pathogenesis of Mycobacterium bovis infection in cattle, focusing on aspects relating to the host rather than the organism. A broad concept of pathogenesis has been considered and information is presented on sources and routes of infection, as well as the immune responses and pathology. In addition, data is presented on the excretion of M. bovis from tuberculous cattle. 相似文献