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101.
Attitudes toward aging were assessed in three groups of elderly men (age 65-85), including: hospitalized veterans, veteran outpatients, and a group of non-hospitalized "healthy" veteran volunteers, using the Rosencranz and McNevin Semantic Differential Scale. Social objects rated included an "old man", a "young man", and the participant, himself, ("self"). Attitudes toward "old men" were significantly more negative than attitudes toward "young men" in all three groups. In addition, significant group by "object-rated" interactions were obtained on the autonomous/dependent and instrumental/ineffective dimensions of this scale. These interactions were attributable to a more negative "self" rating by the hospitalized group. These results suggest that within the population studied, older persons in poor health tend to view themselves more like the stereotyped "old person" than do healthy old people, who tend to perceive themselves as being more like a "young person".  相似文献   
102.
Summary Morphological change of endoneurial and perineurial vessels accompanied severe loss of myelinated axons in peripheral nerves of each of 17 patients with diabetic neuropathy. Vascular mural thickening averaged 18.9±9.9 m2 in diabetic capillaries (n=11) vs. 6.9±4.1 m2 in controls (n=7). Electron microscopy revealed vigorous endothelial proliferation as well as thickening and reduplication of basal lamina in each instance. Particular attention was paid to vessels which penetrate the perineurium en route to the endoneurial intertitium, since they provide a major portion of the endoneurial blood supply. Luminal narrowing and mural thickening of these vessels was compounded by basal laminar thickening of the perineurium. Fenestrated endoneurial capillary endothelium was noted in one case. Both demyelination and axonal degeneration were observed with intra-axonal glycogen accumulation in some axons. Morphometric analysis revealed extensive myelinated nerve fiber loss in diabetic nerves. These morphological findings emphasize the impact of diabetic microangiopathy on specialized endothelium and suggest that local anatomic factors in the perineurial sheath render the nerve vulnerable to chronic ischemia.Supported in part by the National Institute for Communicative Disorders and Stroke NS-14162 and by the Veterans Administration Research Service  相似文献   
103.
The degradation of lidocaine in aqueous solution obeys the expression k obs = (k H+[H +] + k o ) [H+]/([H + ] + K a + ko K a([H + ] + K a) where k H+ is the rate constant for hydronium ion catalysis, and k o and ko are the rate constants for the spontaneous (or water-catalyzed) reactions of protonated and free-base lidocaine. At 80°C, the rate constants for these processes are 1.31 × 10–7 M –l sec–1, 1.37 × 10–9 sec–1, and 7.02 × 10–9sec–1; the corresponding activation energies are 30.5, 33.8, and 26.3 kcal mol–1, respectively. It was found that the room temperature pH of maximum stability is 3–6 and that lidocaine is more reactive in the presence of metal ions such as Fe2+ and Cu2+. The dissociation constant, K a, for lidocaine at 25–80°C was also measured at 0.1 M ionic strength and a plot of pK a versus 1/T gave a slope of (1.88 ± 0.05) × 103 K–1 and intercept 1.56 ± 0.16.  相似文献   
104.
The authors obtained and evaluated antisera from rabbits injected with a derivative of a potent bladder carcinogen, dichlorobenzidine (DCB), conjugated to bovine serum albumin (BSA). A 14C-radioimmunoassay (RIA) was able to detect the presence of DCB antibodies, but its relative insensitivity led to the development of a more sensitive enzyme immunoassay (EIA). The EIA test was a "sandwich" method in which a second antibody, labeled with an enzyme (horseradish peroxidase), was used to measure antibody binding to transferrin (Tf)-conjugated DCB immobilized on a microtiter plate. Antibody titers measured by RIA were approximately 1:40; when measured by EIA, they were approximately 1:40,000. Antibody specificity was assessed by comparing the antibody binding activities of DCB, BSA, Tf, BSA-conjugated to DCB, and a number of N-substituted aromatic compounds that included benzidine (Bz). Among the compounds tested, the rabbit antiserum reacted only with DCB and the carrier protein, BSA. Moreover, antibody binding activity to Tf-conjugated DCB was significantly inhibited by unconjugated DCB concentrations between 30 and 500 ng/mL. The precision of antibody binding activities as a function of DCB concentration (expressed by the CV) ranged from 9% for low (30 ng/mL) DCB levels to 12% for higher (500 ng/mL) levels. This evaluation suggests that the antiserum obtained would be appropriate for detecting DCB levels at the ng/mL level.  相似文献   
105.
Hemoglobin Setif produces pseudosickling of red cells in vitro; the nature of the process and the conditions that "trigger" it are unknown. Studies of red cells, hemolysates, purified hemoglobin solutions, and artificial mixtures of Hb A and Setif suggest that pseudosickling is produced by intracellular crystallization of insoluble hemoglobin. Increased tonicity of the suspending medium accentuates the process, probably by causing a rise in intracellular hemoglobin concentration. If precipitates from A/Setif mixtures are analyzed, they always contain Hb A, suggesting an unusual mechanism for the process. Despite the fact that osmolality in the renal medulla is similar to that which produces pseudosickling in vitro, carriers do not have renal dysfunction of the type found in patients with sickle cell disease.  相似文献   
106.
A study of caries experience and gingivitis prevalence in 6-, 9- and 12-yr-old children attending primary schools in Brisbane was undertaken in November/December 1983. Children from high socioeconomic level (SEL) schools exhibited lower dmft and DMFT scores at all ages. At age 6 yr the proportion of children with caries-free primary dentitions was for high SEL Schools 70%, for middle SEL schools 52% and for low SEL Schools 23%. At 12 yr DMFT scores were 1.8 (high), 2.1 (middle) and 3.3 (low). Similar differences in gingivitis prevalence occurred, children from high SEL schools displaying a much lower proportion of bleeding sites than those from middle and low SEL schools. For selection of children at "high risk" to gingival disease for intensive prevention programmes, an increased emphasis on probing techniques is indicated to achieve diagnostic consistency.  相似文献   
107.
This study replicates the design reported by Schwenk et al and addresses a key methodologic issue in their paper. The original questionnaire by Schwenk et al was administered to one half of the sample of patients, while the other half completed a reworded questionnaire asking what they "want" in the area of psychosocial help, as opposed to what they think their family physician "would" do (the original wording). The hypothesis was that expectations for physician involvement will be higher if patients are asked what they want as opposed to what they expect. Patients were asked to complete a four-page questionnaire, alternating the questions described by Schwenk et al with the reworded questionnaire, in which they were required to rank the level of involvement requested from their physician regarding 45 psychosocial problems (level 1 = no involvement, level 4 = major involvement). Results using the originally worded questionnaire closely paralleled findings of Schwenk et al, whereas asking people what they "wanted" showed statistically significant differences in 18 of the 45 items. The paper concludes with discussion of patient preferences vs patient expectations, with implications for the behavioral science curriculum.  相似文献   
108.
Maternal and Child Health Journal - The purpose of this study was to examine if women’s perceptions of the quality of hospital care during childbirth moderate their risks for symptoms of...  相似文献   
109.
IntroductionDetermining the efficacy of anti-scar technologies can be difficult as qualitative, subjective assessments are often utilized instead of systematic, objective measures. Perceptions regarding the reliability of instruments for quantitative measurements along with their high cost and increased data collection time may discourage their use, leading to use of scar scales which are relatively quick and low-cost. To directly evaluate the reliability of instruments for quantitative measurements of scar properties, instruments and two qualitative scales were compared by assessing a variety of cutaneous scars.MethodsScar height and surface texture were evaluated using a 3D scanner and a mold/cast technique. Scar color was evaluated by using a spectroscopy-based tool, the Mexameter®, and digital photography with image analysis. Scar biomechanics were evaluated using the BTC-2000?, Dermal Torque Meter (DTM®), and ballistometer®. The Vancouver Scar Scale (VSS) and Patient and Observer Scar Assessment Scale (POSAS) were used to qualitatively evaluate the same scar properties. Intraclass correlation coefficients (ICC) were used to determine inter- and intra-user reliability (poor, moderate, good, excellent) with all instruments and the kappa reliability statistic was used to asses inter-user reliability (poor, fair, moderate, good, very good) for VSS and POSAS. Time for measurement collection and after collection analysis was also recorded.ResultsThe Mexameter® was the most reliable method for evaluating erythema and pigmentation compared to digital photography and image processing, POSAS and VSS. Digital photography and analysis was more reliable than POSAS and VSS. Assessment of scar height was significantly more reliable when using a 3D scanner versus VSS and POSAS. The 3D scanner and mold-cast techniques also offered an additional benefit of providing an absolute value of scar height relative to the surrounding tissue. Intra-user reliability for all mechanical tests was moderate to good. Inter-user reliability was greater when using the BTC-2000? and ballistometer® versus the DTM®. All quantitative measurements took less than 90 s for collection, with the exception of the mold/cast technique.ConclusionNon-invasive instruments allow scar properties to be quantitatively assessed with high sensitivity and as a function of time and/or treatment without the need for biopsy collection. Overall, the reliability of scar assessments was significantly improved when quantitative instruments were utilized versus scar scales. Quantitative assessment of color and biomechanics were swift, requiring less than 90 s per measurement while assessments of texture and height required additional analysis time after collection. With proper training of clinical staff and well-defined protocols for measurement collection, reliable, quantitative assessments of scar properties can be collected with little disruption to the clinical workflow.  相似文献   
110.
Pro-inflammatory cytokine and chemokines genes drive prostate cancer progression and metastasis: molecular mechanism update and the science that underlies racial disparity. comprehensive review article.Isaac J. Powell, S. Chinni, S.S. Reddy, Alexander Zaslavsky, Navnath Gavande Introduction: In 2013 we reported that with the use of bioinformatics and ingenuity pathway network analysis we were able to identify functional driver genes that were differentially expressed among a large population of African American men (AAM) and European American men (EAM). Pro-inflammatory cytokine genes were found to be more interactive and more expressed among AAM and have been found to be functional drivers of aggressive prostate cancer (CaP) and aggressiveness in other solid tumors. We examined these genes and biological pathways initiated by these cytokines in primary CaP tissue.Method We unravel the gene network and identified biologic pathways that impacted activation of the androgen receptor, mesenchymal epithelial transition (invasion) and chemokines associated with metastasis in the CaP tissue from 639 radical prostatectomy specimens.Results Biologic pathways identified by unraveling pro-inflammatory genes from our network, more expressed among AAM compared to EAM, were tumor necrosis factor (TNF), IL1b, IL6, and IL8. IL6 and IL8 are downstream of TNF activity and are known activators of androgen receptor and through mediators promote CaP cell proliferation. TNF and IL1b mediate tumor cell invasiveness through the activation of MMP (matrix metalloproteinase) which down regulates E-Cadherin to initiate epithelial mesenchymal transition which allows cells to become invasive in the microenvironment. Ultimately our network analysis indicates that TNF and IL1b activate CXCR4 receptor on CaP cells, which facilitates metastatic progression reportedly by binding to CXCL12 on lipid rafts and tumor implantation in the bone marrow.Conclusion Our retrospective biologic mechanistic model reveals a set of pro-inflammatory cytokines and chemokines that drive CaP aggressiveness, tumor heterogeneity, progression and metastasis. A prospective multi-institutional study needs to be conducted for clinical validation as well consideration of targeted therapy.  相似文献   
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