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21.
Although the conventional method of pain relief during outpatient oocyte recovery involves physician-administered drugs, patient- controlled analgesia (PCA) offers an alternative technique with the potential to give women more control over peroperative analgesia. We conducted a prospective randomized study to compare the effect of fentanyl administered either through a PCA delivery system or by a physician. Thirty-nine women were randomized to PCA during egg collection while 42 were allocated to receive intermittent doses administered by a physician. Pain was evaluated by means of a 100 mm linear analogue scale. The mean (SD) pain score in the PCA group was 38.5 (19.8) while in the other group it was 46.1 (21.3) (P = 0.1). In the PCA group, 64% of women felt very satisfied with their analgesia as compared with 57% in the non-PCA group (P = 0.6). Among the PCA users, 39% of demands were successful. Significantly more fentanyl (97.5 microg) was used in the PCA group than in the other group (84.6 microg) (P = 0.03). Though intraoperative PCA with fentanyl is an effective alternative to physician-administered techniques, many women still feel the need for more analgesia during the procedure.   相似文献   
22.
Morphological studies have shown that macrophages and microglia undergo apoptosis in the central nervous system (CNS) in acute experimental autoimmune encephalomyelitis (EAE) in the Lewis rat. To assess the relative levels of macrophage and microglial apoptosis, and the molecular mechanisms involved in this process, we used three-colour flow cytometry to identify CD45lowCD11b/c+ microglial cells and CD45highCD11b/c+ macrophages in the inflammatory cells isolated from the spinal cords of Lewis rats 13 days after immunization with myelin basic protein (MBP) and complete Freund's adjuvant. Simultaneously, we analyzed the DNA content of these cell populations to assess the proportions of cells undergoing apoptosis and in different stages of the cell cycle or examined their expression of three apoptosis- regulating proteins, i.e. Fas (CD95), Fas ligand (FasL) and Bcl-2. Microglia were highly vulnerable to apoptosis and were over-represented in the apoptotic population. Macrophages were less susceptible to apoptosis than microglia and underwent mitosis more frequently than microglia. The different susceptibilities of microglia and macrophages to apoptosis did not appear to be due to variations in Fas, FasL or Bcl- 2 expression, as the proportions of microglia and macrophages expressing these proteins were similar, and were relatively high. Furthermore, in contrast to T cell apoptosis, apoptosis of microglia/macrophages did not occur more frequently in cells expressing Fas or FasL, or less frequently in cells expressing Bcl-2. These results indicate that the apoptosis of microglia and CNS macrophages in EAE is not mediated through the Fas pathway, and that Bcl-2 expression does not protect them from apoptosis. Expression of FasL by macrophages and microglia may contribute to the pathogenesis and immunoregulation of EAE through interactions with Fas+ oligodendrocytes and Fas+ T cells. The high level of microglial apoptosis in EAE indicates that microglial apoptosis may be an important homeostatic mechanism for controlling the number of microglia in the CNS following microglial activation and proliferation.   相似文献   
23.
OBJECTIVES: To study the efficacy of otoacoustic emissions (OAEs) as a screening test for hearing impairment in children with acute bacterial meningitis. Hearing tests were performed before discharge from the hospital in an attempt to improve coverage and avoid delays in the diagnosis of postmeningitic hearing loss. METHODS: Children with bacterial meningitis were recruited from 21 centers. In the 48 hours before discharge from the hospital, all patients underwent a thorough audiologic assessment consisting of transient evoked OAEs, auditory brainstem responses (ABRs), otoscopy, and tympanometry. Hearing loss was defined as ABR threshold >/=30 dB. The results of OAE screening were compared with the gold standard of ABR threshold. RESULTS: Of 124 children recruited, we were able to perform both OAEs and ABRs on 110 children. Seven (6.3%) of the 110 children had ABR threshold >/=30 dB; 2 had sensorineural hearing loss and 5 had conductive hearing loss. At follow-up, hearing loss persisted in both cases of sensorineural hearing loss and no new cases were identified. All 7 children with hearing loss failed the OAE screening test. Ninety-four children with normal hearing thresholds passed the test, and 9 failed. Thus, the screening test had a sensitivity of 1.00 (95% confidence interval, 0.59 to 1.00), a specificity of 0.91 (0.85 to 0.97), a positive predictive value of 0. 44 (0.20 to 0.70), and a negative predictive value of 1.00 (0.96 to 1.00). CONCLUSIONS: OAE screening in children recovering from meningitis was found to be feasible and effective. The test was highly sensitive and reasonably specific. Inpatient OAE screening should allow early diagnosis of postmeningitic hearing loss and prompt auditory rehabilitation.  相似文献   
24.
Iron-overload diseases frequently develop hepatocellular carcinoma. The genotoxic mechanism whereby iron is involved in hepatocarcinogenesis might involve an oxidative process via the intermediate production of reactive oxygen species. This was presently investigated by examining kinetics of formation and repair of DNA base lesions in primary rat hepatocyte cultures supplemented with the iron chelate, ferric nitrilotriacetate Fe-NTA (10 and 100 microM). Seven DNA base oxidation products have been identified in DNA extracts by gas chromatography- mass spectrometry, which showed a predominance of oxidized-purines (8- oxo-guanine, xanthine, fapy-adenine, 2-oxo-adenine) above oxidized pyrimidines (5-OHMe-uracil, 5-OH-uracil, 5-OH-cytosine) in control cultures. All these DNA oxidation products revealed a significant dose- dependent increase at 4 to 48 h after Fe-NTA supplementation, among which fapy-adenine showed the highest increase and 5-OH-cytosine was the least prominent. Involvement of iron in this oxidative process was established by a correlation between extent in DNA oxidation and intracellular level of toxic low molecular weight iron. DNA excision- repair activity was estimated by release of DNA oxidation products in culture medium. All the seven DNA oxidation products were detected in the medium of control cultures and showed basal repair activity. This DNA repair activity was increased in a time- and dose-dependent fashion with Fe-NTA. Oxidized-pyrimidines, among which was 5-OHMe-Uracil, were preferentially repaired, which explains the low levels detected in oxidized DNA. Since oxidized bases substantially differed from one another in terms of excision rates from cellular DNA, specific excision- repair enzymes might be involved. Our findings, however, demonstrate that even though DNA repair pathways were activated in iron-loaded hepatocyte cultures, these processes were not stimulated enough to prevent an accumulation of highly mutagenic DNA oxidative products in genomic DNA. The resulting genotoxic effect of Fe-NTA might be relevant in understanding the hepatocarcinogenic evolution of iron-overload diseases.   相似文献   
25.
26.

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   
27.
McGee  MP; Wallin  R; Wheeler  FB; Rothberger  H 《Blood》1989,74(5):1583-1590
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   
28.
Einerhand  MP; Bakx  TA; Kukler  A; Valerio  D 《Blood》1993,81(1):254-263
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   
29.
Fletcher  MP; Gasson  JC 《Blood》1988,71(3):652-658
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   
30.
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   
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