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991.
Depression is increasing among Korean college students. Moreover, it is common for depressed individuals to consider attempting suicide. The purpose of this study therefore was to develop and examine the effectiveness of an intervention to reduce suicidal ideation and depression among female college students. Study participants were assigned to either an intervention (n = 27) or control (n = 31) group. The intervention group received a depression-reducing program in eight 1-hr weekly sessions. Measures of suicidal ideation and depression were administered. The program has effects on suicidal ideation and depression among female college students. The findings suggest that the study program may be useful in reducing suicidal ideation and depression among female college students. 相似文献
992.
The effect of parathyroid hormone and calcitonin on the renal excretion of phosphate, calcium, and cyclic AMP was evaluated in the thyroparathyroidectomized hamster, a mammal apparently reisstant to the phosphaturic effect of parathyroid hormone. Parathyroid hormone did not increase phosphate excretion, although it decreased excretion of calcium and increased urinary excretion of cyclic AMP. This lack of a phosphaturic response to parathyroid hormone was not reversed by administration of 25-OH vitamin D or infusions of calcium or phosphate. Calcitonin, another potentially phosphaturic hormone, also vailed to increase phosphate excretion but markedly elevated urinary excretion of cyclic AMP. In hamsters pretreated with infusion of urinary ammonium chloride, which decreased plasma and urinary pH, both parathyroid hormone and calcitonin increased excretion of phosphate as well as that of cyclic AMP. Acetazolamide had no phosphaturic effect in ammonium chloride-loaded hamsters, and it decreased cyclic AMP and calcium excretion. Alkalinization of urine by acetazolamide did not prevent the phosphaturic effect of parathyroid hormone in ammonium chloride-loaded hamsters, but it blocked the increase in urinary cyclic AMP excretion. Parathyroid hormone and calcitonin both stimulated adenylate cyclase in a cell-free system (600-g pellet) from hamster renal cortex, elevated tissue cyclic AMP levels, and activated protein kinase in tissue slices from hamster renal cortex. In acid medium, the increase in cyclic AMP and activation of protein kinase in response to parathyroid hormone was diminished, but addition of acetazolamide restored responsiveness of both parameters to control values. Acetazolamide, on the other hand, did not influence adenylate cyclase or its response to parathyroid hormone or cyclic AMP phosphodiesterase activity. We conclude that the lack of a phosphaturic effect of parathyroid hormone and calcitonin in the hamster depends on steps in the cellular action of these hormones, steps that are sensitive to pH subsequent to cyclic AMP generation and protein kinase activation. In addition, acetazolamide may potentiate the phosphaturic effect of parathyroid hormone by promoting accumulation of cyclic AMP in tissue. Thus, the hamster is a particularly useful model for studies of syndromes in which there is renal resistance to phosphaturic hormones. 相似文献
993.
LeBlanc KE 《Primary care》2004,31(4):1055-1067
The most common ankle injury is a ligamentous sprain, usually involving the lateral side. This is usually treated very successfully with conservative management. Those patients who have continued complaints despite such management should be suspected of having something more than a simple sprain. The diagnostic entities discussed herein should always be part of the differential diagnosis of a sprained ankle, so that when one of these injuries is initially missed, the examining physician will be able to re-examine and eventually diagnose and treat these injuries properly. They should be managed appropriately as soon as possible for the best outcome. Needless delays should be avoided. 相似文献
994.
Objective
The objective of this study is to compare the skill retention of two groups of lay persons, six months after their last CPR training. The intervention group was provided with animation-assisted CPRII (AA-CPRII) instruction on their cellular phones, and the control group had nothing but what they learned from their previous training.Methods
This study was a single blind randomized controlled trial. The participants’ last CPR trainings were held at least six months ago. We revised our CPR animation for on-site CPR instruction content emphasizing importance of chest compression. Participants were randomized into two groups, the AA-CPRII group (n = 42) and the control group (n = 38). Both groups performed three cycles of CPR and their performances were video recorded. These video clips were assessed by three evaluators using a checklist. The psychomotor skills were evaluated using the Resusci®Anne SkillReporter™.Results
Using the 30-point scoring checklist, the AA-CPRII group had a significantly better score compared to the control group (p < 0.001). Psychomotor skills evaluated with the AA-CPRII group demonstrated better performance in hand positioning (p = 0.025), compression depth (p = 0.035) and compression rate (p < 0.001) than the control group.Conclusion
The AA-CPRII group resulted in better checklist scores, including chest compression rate, depth and hand positioning. Animation-assisted CPR could be used as a reminder tool in achieving effective one-person-CPR performance. By installing the CPR instruction on cellular phones and having taught them CPR with it during the training enabled participants to perform better CPR. 相似文献995.
Regulatory T cells can migrate to follicles upon T cell activation and suppress GC-Th cells and GC-Th cell-driven B cell responses 总被引:4,自引:0,他引:4 下载免费PDF全文
How Tregs migrate to GCs, and whether they regulate the helper activity of the T cells in GCs (GC-Th cells) remains poorly understood. We found a T cell subset in human tonsils that displays potent suppressive activities toward GC-Th cell-dependent B cell responses. These Tregs with the surface phenotype of CD4+CD25+CD69- migrate well to CCL19, a chemokine expressed in the T cell zone, but poorly to CXCL13, a chemokine expressed in the B cell zone. This migration toward the T cell-rich zone rapidly changes to trafficking toward B cell follicles upon T cell activation. This change in chemotactic behavior upon activation of T cells is consistent with their switch in the expression of the 2 chemokine receptors CXCR5 and CCR7. CD4+CD25+CD69- Tregs suppress GC-Th cells and GC-Th cell-induced B cell responses such as Ig production, survival, and expression of activation-induced cytosine deaminase. Our results have identified a subset of Tregs that is physiologically relevant to GC-Th cell-dependent B cell responses and a potential regulation mechanism for the trafficking of these Tregs to GCs. 相似文献
996.
Cerebral blood volume (CBV)-weighted endogenous functional contrast can be obtained by the vascular space occupancy (VASO) technique. VASO relies on nonselective inversion for nulling blood signals, but the implementation of VASO at magnetic fields higher than 3 T is difficult due to converging T(1) values of tissue and blood water and a stronger counteracting blood oxygen level-dependent (BOLD) effect. To improve functional CBV sensitivity, we proposed to use VASO with slab-selective inversion (SI-VASO). Computer simulations showed that the SI-VASO approach significantly increases functional sensitivity compared to the original VASO in a stronger magnetic field with a shorter repetition time. To examine layer-dependent specificity, SI-VASO and spin-echo BOLD (SE-BOLD) functional magnetic resonance imaging (fMRI) experiments were performed on isoflurane-anesthetized cats during visual stimulation at 9.4 T. Unlike simultaneously acquired SE-BOLD signal, the SI-VASO signal peaked at 0.9 mm from the surface of the cortex and was localized to the middle cortical layer. The full-width at half maximal response across the cortex was narrower for SI-VASO than for SE-BOLD (1.7 mm vs. 2.5 mm, respectively), suggesting that SI-VASO is better localized to neuronally active sites than SE-BOLD fMRI. The magnitude of the SI-VASO change in the middle cortex was -1.45% with our experimental parameters, corresponding to a relative CBV change of approximately 8% when baseline CBV was assumed to be 5% in a two-compartment model. The signal response profile across the cortex, the calculated CBV change, and the time course of SI-VASO fMRI were similar to those of previously obtained CBV-weighted fMRI with contrast agent in the same animal model, suggesting that SI-VASO measures predominantly functional CBV responses. 相似文献
997.
Induction of suppressor activity in the autologous mixed lymphocyte reaction and in cultures with concanavalin A. 总被引:4,自引:6,他引:4 下载免费PDF全文
T lymphocytes that are activated in the autologous mixed lymphocyte reaction (MLR) have suppressor activity. Concanavalin A (Con A) augments the suppressor activity generated in cultures containing both T and non-T lymphocytes and can induce suppressor activity in T-lymphocyte preparations that contain too few (10%) non-T cells to generate a significant autologous MLR. However, when such T-lymphocyte preparations are further depleted of adherent cells and contain less than 2% non-T cells, Con A fails to induce suppressor activity. These findings support the concept that an autologous MLR may play an important role in generation of suppressor cells by Con A. 相似文献
998.
D T Lowenthal J M Pitone M B Affrime J Shirk P Busby K E Kim J Nancarrow C D Swartz G Onesti 《Clinical pharmacology and therapeutics》1978,23(5):606-615
A single-dose kinetic study of oral timolol, 20 mg, was undertaken in 3 groups of volunteers with varying degrees of renal function--(1) 10 normal subjects (N); (2) 9 patients with moderate chronic renal insufficiency (MCRI; C cr, 20 to 50 ml/min); (3) 4 patients with end-stage renal disease (ESRD)--to assess the need for dosage modification as renal function diminishes. There were borderline statistical differences in absorption between groups. The mean peak concentration (C max) was 84.3 +/- 44.8 ng/ml at 0.8 +/- 0.4 hr for N and 87.1 +/- 22.8 ng/ml at 1.7 +/- 1.2 hr (p, NS) for MCRI. N and MCRI mean half-lives (5.2 +/- 2.6 hr and 4.0 +/- 1.2 hr) were not statistically different. Salivary levels correlated with plasma levels in 3 N and 1 MCRI patient. Group differences in blood pressure and pulse response to timolol seems to reflect differences present at baseline with percent change from baseline identical for the two groups except at 12 to 24 hr. Administration of timolol on an interdialysis day revealed similar kinetic and physiologic response in the normal and the MCRI group. During dialysis, timolol, 20 mg, induced significant hypotension and bradycardia. 相似文献
999.
Zhang L Kolokythas O Dighe M Kim JH Leca N Kim Y 《Ultrasound in medicine & biology》2010,36(12):2011-2017
The resistive index (RI) is a functional hemodynamic index used to measure flow resistance within an organ, such as the kidney, to assess if there is any vascular disease associated with that organ. Currently, the measurement of RI values using spectral Doppler ultrasound (US) is performed in one location at a time. As a result, RI values are typically obtained only from a few locations. To visualize the entire two-dimensional distribution of RI values, we developed a method called two-dimensional flow index mapping (2D-FIM). To evaluate this method, we performed a feasibility study using 16 kidney data sets, with eight from healthy volunteers with normal native kidneys and eight from kidney transplant recipients. Quadrature-demodulated baseband Doppler data were used to calculate the spatial distribution of RI values using 2D-FIM. For comparison, the intrarenal RI values at different levels of renal arterial branches were measured with conventional spectral Doppler US. The RI values determined from 2D-FIM were compared with those from spectral Doppler US, which led to a Pearson correlation coefficient of 0.84. There was no significant difference between 2D-FIM- and spectral Doppler US-produced RI values. With the ability to visualize RI in more than one dimension, 2D-FIM could help guide placement of the spectral Doppler range gate to regions of abnormal RI, thus potentially reducing exam times. 相似文献
1000.
Anxiety sensitivity (AS), or the fear of anxiety sensations, has been shown to independently predict poorer health-related quality of life (HRQOL) in adults with chronic pain. Specifically, AS was found to contribute to decrements in psychological well-being and social functioning but not to decrements in physical functioning. Existing studies have not examined the relationship between AS and HRQOL in children with chronic pain. The present study used multivariate regression analysis to test the association between AS and self-reported HRQOL in 87 children (62 girls; mean age = 14.4 years +/-2.3) presenting for treatment at a tertiary, multidisciplinary clinic specializing in pediatric chronic pain. After controlling for key sociodemographic and pain-related characteristics, higher AS was associated with poorer perceived general and mental health, greater impairment in family activities, lower self-esteem, increased behavior problems, and more social/academic limitations due to emotional problems. AS accounted for 4% to 28% of incremental variance in these HRQOL domains above and beyond the demographic and pain-related variables. However, AS was not significantly associated with physical functioning or with academic/social limitations due to physical health. Additional research is required to delineate possible mechanisms by which AS may influence certain aspects of children's HRQOL but not others. PERSPECTIVE: The present findings support the evaluation of AS in pediatric chronic pain patients as part of a comprehensive assessment battery. The links between AS and multiple HRQOL domains suggest that treatment components aimed at reducing AS may lead to enhanced psychosocial well-being in children with chronic pain. 相似文献