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21.
Yuli R Tak Rinka MP Van Zundert Rowella CWM Kuijpers Boukje S Van Vlokhoven Hettie FW Rensink Rutger CME Engels 《BMC public health》2012,12(1):21
Background
The incidence of depressive symptoms increases during adolescence, from 10.0% to 24.5% at age 11 to 15, respectively. Experiencing elevated levels of depressive symptoms increases the risk of a depressive disorder in adulthood. A universal school-based depression prevention program Op Volle Kracht (OVK) was developed, based on the Penn Resiliency Program, aimed at preventing the increase of depressive symptoms during adolescence and enhancing positive development. In this study the effectiveness of OVK will be tested and possible mediators of program effects will be focus of study as well. 相似文献22.
Subcutaneous emphysema,pneumoretroperitoneum, and pneumomediastinum following rectal surgery: Report of a case and review of the literature 总被引:1,自引:0,他引:1
Renato A. Bonardi M.D. Dr. John D. Rosin M.D. Erwin Witkin M.D. 《Diseases of the colon and rectum》1976,19(8):710-712
Summary A case of retroperitoneal, mediastinal, and subcutaneous emphysema following rectal surgery is described. This complication
has not been reported in medical literature. Treatment was based on the fear of a more extensive and irreversible situation,
because on the basis of the single case, it could not be demonstrated that the intestinal gas was not associated with infection. 相似文献
23.
24.
Initiation of the extrinsic pathway of coagulation by human and rabbit alveolar macrophages: a kinetic study 总被引:3,自引:0,他引:3
We examined assembly and expression of the factor X activating complex on human and rabbit alveolar macrophages. Kinetic parameters of the factor X activating reaction were determined by functional titrations of factors VII and X with macrophage tissue factor (TF) added. We found rapid activation of factor X to Xa on alveolar macrophage surfaces. Detection of rapid factor Xa formation on macrophages required addition of exogenous factors VII and X. At plasma concentrations of the purified factors, factor Xa was formed on freshly isolated macrophages at approximately 5.4 pmol/min/10(6) cells. After macrophage maturation in culture for 20 hours with LPS (endotoxin) added, the factor X activation rate was increased two- to sixfold. The km' (apparent km) of TF-factor VII enzymatic complexes assembled on alveolar macrophages for factor X were (258 +/- 55 and 475 +/- 264 nmol/L for human and rabbit cells, respectively). The km' did not change during macrophage maturation in culture, but V'max (apparent Vmax) was consistently increased. The K1/2 of human factor VII (concentrations giving half maximal rates of factor X activation) for the interaction with human and rabbit alveolar macrophage TF were 0.191 +/- 0.096 and 1.7 +/- 0.7 etamol/L, respectively. The K1/2 were not significantly changed after maturation, whereas rates of Xa formation at saturation with factor VII were increased. The fast rates of factor X activation observed at physiologic concentrations of plasma-derived factors VII and X indicate that TF on alveolar macrophages is likely to provide sites for binding of factor VII and activation of factor X in vivo during clotting reactions associated with alveolar edema and inflammation. 相似文献
25.
Factors affecting the transduction of pluripotent hematopoietic stem cells: long-term expression of a human adenosine deaminase gene in mice 总被引:5,自引:0,他引:5
An amphotropic retroviral vector, LgAL(delta Mo + PyF101) containing a human adenosine deaminase (ADA) cDNA was used to optimize procedures for the lasting genetic modification of the hematopoietic system of mice. The highest number of retrovirally infected cells in the hematopoietic tissues of long-term reconstituted mice was observed after transplantation of bone marrow (BM) cells that had been cocultured in the presence of both interleukin-1 alpha (IL-1 alpha) and IL-3. A significantly lower number was detected when IL-1 alpha was omitted from such cocultures. The yield of cells that generate spleen colony-forming cells (CFU-S) in the BM of lethally irradiated recipients (MRA-CFU-S) significantly improved on inclusion of the adherent cell fraction of cocultures in the transplant. Retroviral integration patterns in MRA-CFU-S-derived spleen colonies showed that an MRA-CFU-S can produce many CFU-S during BM regeneration. Expression of hADA was detected in the circulating white blood cells of long-term reconstituted animals, demonstrating that the LgAL(delta Mo + PyF101) vector is capable of directing the sustained expression of hADA, and in approximately 35% of the transduced MRA-CFU-S-derived spleen colonies. These results should facilitate the development of gene therapy protocols for the treatment of severe combined immunodeficiency caused by a lack of functional ADA. 相似文献
26.
Enhancement of neutrophil function by granulocyte-macrophage colony- stimulating factor involves recruitment of a less responsive subpopulation 总被引:3,自引:0,他引:3
Human granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances numerous functions of mature neutrophils (PMN) including phagocytosis, superoxide responses to chemotaxins, antibody-dependent cellular cytotoxicity, and expression of complement receptors. A central question concerns whether the mechanism of enhancement involves quantitative increases in the response of all cells v subpopulation recruitment. The effects of GM-CSF on individual cell light scatter changes, membrane potential, and oxidant responses induced by the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (FMLP) were assessed by flow cytometry and by scoring individual cells for nitroblue tetrazolium dye (NBT) reduction. GM-CSF produced a dose- and time-dependent shift in forward light scatter that was very similar in character to that seen with FMLP or leukotriene B4 stimulation. Although not capable of depolarizing the cells directly, GM-CSF primed PMNs for enhanced membrane potential responses to FMLP by significantly increasing the proportion of depolarizing cells when compared with diluent-treated controls after a 60-minute incubation at 37 degrees C (79.4% +/- 3.4% v 29.5% +/- 4.7% GM-CSF v diluent, mean +/- SE, P less than .005, n = 11). Subpopulation recruitment by GM-CSF treatment was also demonstrated by the FMLP-elicited NBT test. Taken together, these results indicate that GM-CSF can modulate the function of mature PMN by enhancing the proportion of responsive cells. 相似文献
27.
Bash RO; Crist WM; Shuster JJ; Link MP; Amylon M; Pullen J; Carroll AJ; Buchanan GR; Smith RG; Baer R 《Blood》1993,81(8):2110-2117
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study. 相似文献
28.
A non-human primate antiserum was prepared to acute lymphoblastic leukemia of T-cell phenotype (T-ALL) and, after absorptions with normal blood elements, reacted by immunofluorescence and microcytotoxicity to all the T-ALL tested. In addition, the antiserum reacted with cells from about 70% of the common ALL studied and immunoprecipitated the common ALL antigen of 100,000 daltons. However, when the anti-T-ALL serum was absorbed with with lymphoblasts from common ALL, it failed to react with common ALL lymphoblasts, yet reacted significantly with cells from patients with T-ALL phenotype and defined a 100,000-dalton membrane component not found on common ALL lymphoblasts. In addition, sequential immunoprecipitation of 125I-labeled T-ALL membranes by anti- common-ALL serum followed by anti-T-ALL serum detected the T-ALL membrane component of 100,000 daltons that was not found on common ALL. Thus, our results demonstrate the presence of of a unique human T-ALL antigen present on all T-ALL distinct from the common ALL antigen. 相似文献
29.
Joseph C. Gigliotti Liping Huang Amandeep Bajwa Hong Ye Eric H. Mace John A. Hossack Kambiz Kalantari Tsuyoshi Inoue Diane L. Rosin Mark D. Okusa 《Journal of the American Society of Nephrology : JASN》2015,26(10):2470-2481
We showed previously that prior exposure to a modified ultrasound regimen prevents kidney ischemia-reperfusion injury (IRI) likely via the splenic cholinergic anti-inflammatory pathway (CAP) and α7 nicotinic acetylcholine receptors (α7nAChR). However, it is unclear how ultrasound stimulates the splenic CAP. Further investigating the role of the spleen in ischemic injury, we found that prior splenectomy (–7d) or chemical sympathectomy of the spleen with 6-hydroxydopamine (6OHDA; –14d) exacerbated injury after subthreshold (24-minute ischemia) IRI. 6-OHDA–induced splenic denervation also prevented ultrasound-induced protection of kidneys from moderate (26-minute ischemia) IRI. Ultrasound-induced protection required hematopoietic but not parenchymal α7nAChRs, as shown by experiments in bone marrow chimeras generated with wild-type and α7nAChR–/– mice. Ultrasound protection was associated with reduced expression of circulating and kidney-derived cytokines. However, splenocytes isolated from mice 24 hours after ultrasound treatment released more IL-6 ex vivo in response to LPS than splenocytes from sham mice. Adoptive transfer of splenocytes from ultrasound-treated (but not sham) mice to naïve mice was sufficient to protect kidneys of recipient mice from IRI. Ultrasound treatment 24 hours before cecal ligation puncture–induced sepsis was effective in reducing plasma creatinine in this model of AKI. Thus, splenocytes of ultrasound-treated mice are capable of modulating IRI in vivo, supporting our ongoing hypothesis that a modified ultrasound regimen has therapeutic potential for AKI and other inflammatory conditions. 相似文献
30.