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31.
Janet Audrain Caryn Lerman Andres Gomez-Caminero Neal R. Boyd C. Tracy Orleans 《Journal of Applied Biobehavioral Research》1998,3(1):29-42
Studies point to an association between anxiety and smoking. However, the mechanisms linking trait anxiety and nicotine dependence have not been evaluated fully. Potential mediators include self-medication variables (e.g., use of nicotine to manage anxiety) and cognitive variables (e.g., lower levels of self-efficacy). The present study explored these mechanisms in a sample of 352 male and female smokers. The results showed that trait anxiety correlated significantly with negative affect smoking (r= .29, p= .0001), stimulation smoking (r=.15, p = .007), and nicotine dependence (r= .20, p= .0003). Trait anxiety also correlated significantly with self-efficacy (r =-.22, p = .0003). Regression analyses revealed that trait anxiety predicted nicotine dependence after controlling for depression, education, race, age, and marital status (R2= .09, p = .0001). Path modeling indicated that both negative affect smoking and quitting self-efficacy mediated the relationship between trait anxiety and nicotine dependence. Interventions that emphasize the management of anxious mood and quitting confidence may benefit anxious smokers. 相似文献
32.
H. Seckfort W. Busanny-Caspari E. Andres 《Journal of molecular medicine (Berlin, Germany)》1960,38(12):606-608
Zusammenfassung Unsere Untersuchungen haben zu folgenden Ergebnissen geführt.1. Kurzfristige ACTH-Injektionen wirken sich — im Gegensatz zum Cortison — deutlich auf das Serumlipoidbild gesunder Ratten aus.2. Die auftretenden Blutlipoidverschiebungen sind — vor allem qualitativ — in weitgehendem Maße vom Funktionszustand des Leberparenchyms abhängig.3. Diese Änderungen der Serumlipoidkonzentrationen unterscheiden sich deutlich von denen, die unter gleichen Bedingungen nach Cortisoninjektionen zu beobachten sind.4. Auf den Fettgehalt der Leberzellen gesunder und teilhepatektomierter Ratten wirkt sich die kurzfristige ACTH-Applikation nicht aus.Herrn Prof. Dr.K. Voit zum 65. Geburtstag. 相似文献
33.
M. J. Hutchinson Patrick T. Harrison R. Andres Floto Janet M. Allen 《European journal of immunology》1995,25(2):481-487
Receptors for the invariant chain of immunoglobulins (FcR) define the cellular response to specific antigens. FcγR recognize IgG and so elicit a variety of effector functions including phagocytosis. We are interested in the structural determinants for FcγR-mediated phagocytosis, specifically FcγRI(p135) and FcγRIIa isoforms. The low-affinity receptor, FcγRIIa, is found on macrophages and its cytoplasmic domain contains a tyrosine activation motif which has previously been shown to regulate endocytosis. In contrast, FcγRI has no known signaling motifs, though a functional interaction has recently been demonstrated with the γ chain of the high-affinity receptor for IgE, FcεRI. This accessory molecule has a cytoplasmic tyrosine activation motif implicated in signal transduction. Here we demonstrate that although FcγRI transiently expressed on COS-7 cells is able to rosette opsonized SRBC, it cannot phagocytose them. If the cytoplasmic domain of either γ chain or FcγRIIa replaces that of FcγRI in a chimeric receptor, efficient phagocytosis occurs. This particle ingestion is sensitive to the tyrosine kinase inhibitor genistein. Chimeric receptors where the extracellular domain of either FcγRI or FcγRIIa is replaced with that of CD2, a T cell antigen, indicate that FcγR-mediated phagocytosis is ligand independent. We conclude that phagocytosis is dependent upon close particle apposition, tyrosine kinase activity, and that the process is ligand independent. 相似文献
34.
Changes in Serum Immunoglobulin G Levels as a Marker for Cryptosporidium sp. Infection in Peruvian Children
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35.
Gastric Sensory and Motor Functions and Energy Intake in Health and Obesity—Therapeutic Implications
Sensory and motor functions of the stomach, including gastric emptying and accommodation, have significant effects on energy consumption and appetite. Obesity is characterized by energy imbalance; altered gastric functions, such as rapid gastric emptying and large fasting gastric volume in obesity, may result in increased food intake prior to reaching usual fullness and increased appetite. Thus, many different interventions for obesity, including different diets, anti-obesity medications, bariatric endoscopy, and surgery, alter gastric functions and gastrointestinal motility. In this review, we focus on the role of the gastric and intestinal functions in food intake, pathophysiology of obesity, and obesity management. 相似文献
36.
37.
Joseph G. Cheaib Lauren E. Claus Hiten D. Patel Max R. Kates Andres Matoso Noah M. Hahn Trinity J. Bivalacqua Jean H. Hoffman-Censits Phillip M. Pierorazio 《Urologic oncology》2021,39(1):74.e9-74.e16
PurposeMetastatic recurrence occurs in over 25% of upper tract urothelial carcinoma patients treated with radical nephroureterectomy. While metastatic recurrence suggests poor prognosis, the impact of the specific site of recurrence on prognosis is not well documented.Materials and methodsWe retrospectively analyzed 188 patients who underwent radical nephroureterectomy for high-grade, node-negative upper tract urothelial carcinoma at our institution from 2003 to 2018 without receiving neoadjuvant or adjuvant chemotherapy. Competing-risks survival analysis was performed to evaluate the cumulative incidence and predictors of metastatic recurrence. The Kaplan-Meier method and log-rank test were used to estimate and compare recurrence site-specific survival probabilities following metastatic recurrence. Cox regression analyses were performed to assess site-specific prognoses.ResultsOf the 188 patients, 47 (25%) developed metastatic recurrence over a median follow-up of 30 months (interquartile range: 10.5–58.5 months). The 1- and 2-year cumulative incidences of metastatic recurrence were 13.6% and 23.6%, respectively. On multivariable analysis, lymphovascular invasion was significantly predictive of metastatic recurrence (subhazard ratio: 2.6, P = 0.01). Of the 47 patients who developed recurrence, 38 (80.9%) died over a median follow-up of 10 months (interquartile range: 5–20 months). Metastatic recurrence was most common in the lungs (n= 13, 28%) and at multiple sites (n= 14, 30%). Median time to recurrence was shorter for recurrences at multiple sites (6.5 months) and those in the liver (13 months) and bone (18 months) compared to other sites. Patients who recurred in the liver (hazard ratio: 6.3, P = 0.007), bone (hazard ratio: 4.9, P = 0.02), and multiple sites (hazard ratio: 4.6, P = 0.01) had significantly worse prognosis compared to those who recurred in lymph nodes. Statistical significance persisted after adjusting for treatment with salvage therapy.ConclusionsA significant proportion of high-grade upper tract urothelial carcinoma patients recur systemically after radical nephroureterectomy. Lymphovascular invasion is a predictor of metastatic recurrence and may inform decisions regarding perioperative chemotherapy. Hepatic and osseous recurrences have relatively quicker onset and less favorable prognosis compared to other sites. These findings may benefit future efforts to develop recurrence site-specific treatment plans and highlight the necessity of subsequent endeavors to explore the genetic associations of recurrence in upper tract urothelial carcinoma. 相似文献
38.
The most frequent form of idiopathic calcinosis is tumoral calcinosis (TC) which rarely occurs at young ages. We describe
here a TC case of a young boy with its light microscopy completed with electron microscopic examinations. X-ray microanalysis
revealed in the intracellular crystals CaCl2 besides the previously described hydroxyapatite. The significance of this finding is unknown at the moment. 相似文献
39.
Merrick MA Rankin JM Andres FA Hinman CL 《Medicine and science in sports and exercise》1999,31(11):1516-1521
PURPOSE: The purpose of this study was to document the presence of secondary injury in skeletal muscle, to quantify it, and to determine whether it is altered by acute cryotherapy. METHODS: Crush injuries to the triceps surae of 19 adult male Sprague-Dawley rats were either treated continuously with ice for 5 h (N = 10) or received no ice treatment (N = 9). After treatment, tissues were assayed for the reduction of triphenyltetrazolium chloride (TTC) to triphenylformazan (formazan red). TTC reduction is indicative of oxidative function and serves as an indicator of cellular damage. RESULTS: A significantly lower TTC reduction rate was seen in both cold-treated injured tissue (6.59 +/- 1.01 microg x mg(-1) x h(-1)) and nontreated injured tissue (4.48 +/- 0.79 microg x mg(-1) x h(-1)) compared with uninjured controls (ice group = 7.94 +/- 1.49 microg x mg(-1) x h(-1), no-ice group = 6.62 +/- 0.75 microg x mg(-1) x h(-1)). These data indicate that crushing of muscle tissue produces injury measurable with the TTC reduction assay. Additionally, in crush-injured tissues, a significantly lower TTC reduction rate was seen in untreated tissues (4.48 +/- 0.79 microg x mg(-1) x h(-1)) compared with ice treated tissues (6.59 +/- 1.01 microg x mg(-1) x h(-1)), indicating that cryotherapy reduces the magnitude of secondary injury. CONCLUSIONS: From these data, it can be concluded that secondary injury occurs after primary crush injury and that secondary injury is retarded by acute treatment with 5 h of continuous cryotherapy. 相似文献
40.
Jaussi A Savcic M Delabays A Kappenberger L 《Echocardiography (Mount Kisco, N.Y.)》1996,13(3):281-286
Background: Exercise echocardiography (EE) is being used increasingly as an investigative technique now that dynamic images can be captured digitally. Its equivalent reliability with scintigraphic methods has been demonstrated in a hospital setting. This study analyzes its impact on daily practice. Materials and Methods: Standardized progressive stress was produced by supine bicycle ergometry. Echocardiographic images of complete cardiac cycles were obtained in standard apical and parasternal short-axis views before, during, and after maximum effort, and digitized for simultaneous analysis of synchronized images at rest and during exercise. Two hundred sixteen patients (175 men and 41 women; mean age 58 ± 10 years) were studied. Results: Image quality was suboptimal in 4 cases. In the remaining 212 cases, ischemia was detected in 91 cases, and the test was negative in 114 cases and doubtful in 7 cases. Control by selective coronary angiography, as indicated by the clinical situation, was performed in 52 cases. In this particular group, EE showed 87% sensitivity, which is significantly higher than the 59% recorded for conventional exercise testing (P > 0.0001). Conclusions: EE by bicycle ergometer in the supine position is a valid, noninvasive investigative technique that can be used in an outpatient situation (feasibility 95%) since it is readily available. Its value appears to be greatest in cases in which exercise ECG is not conclusive. A negative result enables the initial cardiologist to reassure the patient immediately, which has been demonstrated in the literature to have favorable prognostic value. 相似文献