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911.
S Poucell-Hatton PS Perkins TJ Deerinck MH Ellisman WG Hardison SJ Pandol 《Canadian Metallurgical Quarterly》1997,113(2):649-658
BACKGROUND & AIMS: The mechanisms whereby intracellular messengers mediate zymogen granule transport and exocytosis in the pancreatic acinar cell are not well defined. Electron microscopy has shown a periluminal network of actin in the acinar cell, suggesting a role for actin and myosin in the transport process. The possible involvement of two types of myosin in the secretory process was investigated, and their distribution in acinar cells was determined. METHODS: Antibodies specific to myosin I or to myosin II were used for immunocytochemistry and Western blot analysis. Ultrastructural studies were also performed. RESULTS: Western blot analysis showed that myosin I and myosin II were present in total pancreatic homogenate but that only myosin I was present on isolated zymogen granules and their membranes. By immunocytochemistry, myosin I was shown in the apical aspect of acinar cells colocalized with glycoprotein 2, a marker for zymogen granules, and actin. By immunocytochemistry, myosin I was also localized on isolated zymogen granules. CONCLUSIONS: The immunolocalization of myosin I to zymogen granule membranes and its close association with periluminal actin suggest that myosin I plays a direct role in the process of transport and exocytosis of zymogen granules in the pancreatic acinar cell. 相似文献
912.
OBJECTIVES: To investigate the occurrence of AIDS dementia complex (ADC) in Italy and its incidence over time, examining possible correlations between this condition and some demographic and immunological variables. DESIGN: Inception cohort. Data collected from the case notification forms of the Italian National AIDS Registry. SUBJECTS: 16813 consecutive AIDS cases reported to the National AIDS Registry from August 1, 1987 through October 31, 1993 were included. STATISTICAL METHODS: All data refer to the time of AIDS diagnosis as reported on the case notification forms. Main analyses of the monthly proportion of ADC cases were by multiple logistic regression. RESULTS: 1364 subjects (8.1%) were reported with a diagnosis of ADC as the first AIDS defining disease, either as the only manifestation or associated with other AIDS defining conditions. At the time of AIDS diagnosis, the observed ADC/AIDS proportion was significantly higher among intravenous drug users (IVDU), 9.1%, compared to heterosexuals, 6.3%, and homo-bisexual men, 5.2%. Simple logistic regression analysis showed a significant (p < 0.0001) quadratic trend in the monthly ADC/AIDS proportion, peaking in March 1990 and decreasing thereafter. Multiple logistic regression, adjusting for month of diagnosis, showed that IVDUs have consistently the highest risk and homo-bisexual men the lowest, although differences tended to decrease with increasing age. Older age, in fact, was highly associated with an increased risk, especially within the homo-bisexual and heterosexual transmission categories. CD4 + cells counts proved to have no significant effect on the risk of progressing to AIDS with ADC rather than with any other AIDS indicative disease. CONCLUSIONS: ADC is a relatively frequent manifestation at diagnosis of AIDS among Italian patients, and particularly in IVDUs. Differences in its occurrence were found according to time of diagnosis, transmission category and age. 相似文献
913.
914.
TJ Covington 《Canadian Metallurgical Quarterly》1993,6(2):161-167
Pain, or at least discomfort in the form of hypersensitivity, is always a sequela to nerve injury and nerve repair. A carefully planned pain evaluation and treatment program has been shown to result in a decrease in pain and improved function. For a hand therapist, the commitment to evaluation and management of pain is a personal as well as a professional dedication. Patients may greatly vary in their responses to injury, symptomatology, and treatment interventions. Although the hand therapist can successfully intercede with many patients, it is often advantageous to involve a clinical psychologist. Psychosocial and psychophysiologic data can be imperative in evaluating the possibilities of patient outcome with regard to pain, evaluation, and treatment. Psychophysiologic information is likely to increase the hand therapist's evaluation and treatment potency. A psychological assessment and/or intervention is appropriate at several points of treatment--for example, after an appropriate interval of healing time in which an injury should resolve itself, after a major invasive procedure such as surgery, or when a condition is chronic and all other avenues of treatment have been unsuccessful. 相似文献
915.
916.
TJ Hamblin 《Canadian Metallurgical Quarterly》1997,21(11-12):1025-1026
917.
LA Fernandez R Cheng I Sadek TJ Nevill JM Macsween 《Canadian Metallurgical Quarterly》1997,108(3):557-561
The extracellular calcium-binding (EC) module of human testican (115 residues) was obtained in native form by recombinant production in mammalian cell culture and thus shown to represent an independently folding domain. This module showed a large loss in alpha-helix upon calcium depletion. Apparently only one of the two EF hands binds calcium, with a moderate affinity (Kd =68 microM) about 100-fold lower than in the homologous BM-40 protein. No clear evidence was obtained for collagen binding, indicating that EC modules found in different proteins may not share similar functions. 相似文献
918.
NJ Horwood J Elliott TJ Martin MT Gillespie 《Canadian Metallurgical Quarterly》1998,139(11):4743-4746
The osteoclastogenic factor of osteoblastic origin has recently been elucidated as a novel Tumor Necrosis Factor (TNF)-ligand family member, termed osteoclast differentiation factor (ODF). Using a semiquantitative RT-PCR approach, we sought to determine the mRNA expression of ODF and its decoy receptor, osteoprotegerin (OPG), in a selection of osteoblastic cell lines and in response to three factors representative of different signal transduction pathways, vitamin D receptor, protein kinase A or gp130. Each osteotropic agent, either 1,25-(OH)2D3, PTH or IL-11, promoted an increase in the ratio of ODF:OPG, with maximal stimulation occurring at 24 h, 4 h, and 8 h, respectively, and furthermore each was shown to act in a dose-dependent manner. This report establishes that osteoblastic cell lines incapable of supporting osteoclast formation have markedly reduced ODF expression and also illustrates the importance of the relative abundance of ODF compared with the levels of OPG for the induction of osteoclastogenesis. 相似文献
919.
Ulcerations may appear on the genitalia in a variety of both infectious and noninfectious conditions. The vast diversity of etiologies, coupled with the often overlapping morphological features, make the diagnosis of genital ulcerations a challenging endeavor. This article highlights the most important clinical manifestations and laboratory findings which aid in the proper diagnosis of genital ulcerations. 相似文献
920.