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521.
To clarify the concept framework to assess web based information systems (WIS) evolution from an information perspective instead of the usual systems perspective, and to seek for in-depth understanding of maturing patterns of WISs based on the framework, several central concepts related to the information aspect of WIS are firstly discussed, then a growth model of local government websites based on a survey study is proposed. 相似文献
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523.
SD Chipman HO Sweet DJ McBride MT Davisson SC Marks AR Shuldiner RJ Wenstrup DW Rowe JR Shapiro 《Canadian Metallurgical Quarterly》1993,90(5):1701-1705
Osteogenesis imperfecta (OI) is a heritable disorder of connective tissue associated with fractures, osteopenia, and short stature. OI results from mutations affecting the pro alpha 1 or pro alpha 2 gene of type I collagen. We describe a strain of mice with a nonlethal recessively inherited mutation (oim) that results in phenotypic and biochemical features that simulate moderate to severe human OI. The phenotype of homozygous oim mice includes skeletal fractures, limb deformities, generalized osteopenia, and small body size. Their femurs are smaller and demonstrate marked cortical thinning and fewer medullary trabeculae than those of wild-type mice. Breeding studies show the mutation is inherited in most crosses as a single recessive gene on chromosome 6, near the murine Cola-2 gene. Biochemical analysis of skin and bone, as well as isolated dermal fibroblast cultures, demonstrate that alpha 1(I) homotrimeric collagen accumulates in these tissues and is secreted by fibroblasts. Short labeling studies in fibroblasts demonstrate an absence of pro alpha 2(I) collagen chains. Nucleotide sequencing of the cDNA encoding the COOH-propeptide reveals a G deletion at pro alpha 2(I) nucleotide 3983; this results in an alteration of the sequence of the last 48 amino acids. The oim mouse will facilitate the study of type I collagen-related skeletal disease. 相似文献
524.
B Riedl M Nischik F Birklein B Neund?rfer HO Handwerker 《Canadian Metallurgical Quarterly》1998,69(2-3):83-88
Acetylcholine (ACh) applied to human skin is known to elicit a sweat response, which consists of a direct muscarinergic (M3) activation of sweat glands and a nicotinic axon reflex response from sudomotor terminals. To visualize the extent of axon reflex sweating after ACh-iontophoresis, iodine starch staining was used. Iontophoresis was performed under occlusion at the peroneal aspects of the lower leg and the center of the foot dorsum of healthy volunteers (n = 10). Ten minutes after stimulation, the area of dark blue staining was recorded by a video camera. Control experiments were performed with saline, histamine, pilocarpine and nicotine iontophoresis. The stained area was measured and the maximum and minimum distance of its boundary from the edge of the iontophoresis probe was determined (maximum/minimum radius). Sizes of stained areas and maximum radii were significantly greater on the lower leg compared to the foot (P < 0.01). The median sizes of the stained areas on the leg were 14.6 cm2 and on the foot dorsum 8.0 cm2. The respective median maximum radii were 3.1 cm on the leg and 2.3 cm on the foot dorsum (median minimum, leg 1.1 cm, foot 0.8 cm). These results match microneurographic findings of innervation territories of sympathetic efferent units. Area sizes of stained skin showed a close correlation between both stimulation sites (R = 0.96, P < 0.01), i.e. the sizes of sweat responses on leg and foot show a constant relation (foot/leg = 0.57) in spite of their great interindividual variability. This novel technique of establishing sweat responses provides information on the size of sudomotor innervation territories and may be useful for clinical studies in patients with suspected impairment of sympathetic functions. 相似文献
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526.
Jes Christoffersen Henrik Myhre Jensen 《Mechanics of materials : an international journal》1996,24(4):305-315
Failure in compression of uni-directional fiber composites by fiber kinking is analyzed. General rate constitutive equations for fiber composites are formulated. These equations are used in treating fiber kinking as a problem of localization of deformation. The condition for fiber kinking is compared with previously published results for rigid fibers, and some notable differences are reported. The work unifies theories of kink band and shear band formation. 相似文献
527.
An evaluation of the Mono-Chek test shows it to be easy to read, fast and simple. In accuracy it compares favorably with the Paul-Bunnell (P-B) test and the Davidsohn modification of the Paul-Bunnell (P-B-D) test and is equal to the Mono-Spot test. 相似文献
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529.
H Takita C Merrin MS Didolkar HO Douglass F Edgerton 《Canadian Metallurgical Quarterly》1977,24(4):359-364
From 1970 to June, 1976, 56 patients who had multiple metastatic tumors of the lung were treated by lung resection. Most of the bilateral lung lesions were removed through a median sternotomy so as to avoid staged bilateral thoracotomy. The surgical mortality was 1.8%. A total of 26 patients are alive at 7 to 69 months (estimated median survival, 20.7 months). Patients with tumor doubling time of less than 40 days had lower survival results (median, 9.5 months), compared to patients with tumor doubling time of more than 40 days (median not yet reached). The type of primary tumor, tumor-free interval, number of lesions removed, and presence of unilateral as opposed to bilateral lung metastases did not seem to affect the therapeutic results. 相似文献
530.
The paper presents the results of a behavioural programme designed to increase social interaction and activity in the locked ward of a psychiatric hospital. The intervention used a method of information feedback to staff to encourage them to make informed choices of targets and methods of change. The rationale was that this would enhance generalization and programme maintenance. Evidence is presented to show the extent of change obtained after 6 months. 相似文献