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31.
Bhattacharya S; MacLennan F; Hamilton MP; Templeton A 《Human reproduction (Oxford, England)》1997,12(7):1440-1442
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
32.
Two new studies examine the recombinational history of humanchromosomes that nondisjoin at the first meiotic division infemales. Our analysis of these studies suggests two possibleetiologies of nondisjunction in terms of well-understood propertiesof chromosome mechanics. For both the X chromosome and for chromosome21, 6070% of nondisjoined chromosomes are derived fromchlasmate bivalents, many of which display unusual patternsof exchange. The patterns of exchange and nondisjunction observedfor human chromosome 21 parallel those exhibited by a mutationin Drosophila that impairs spindle assembly and function. Basedon these similarities, we propose that nondisjunction of chromosome21 in human females results from an age-dependent loss of spindle-formingability. The recombinational histories of nondisjoining humanX chromosomes are quite different from those of chromosome 21,but rather parallel those obtained for spontaneous nondisjunctionin Drosophila females. The data for X chromosome disjunctionin both species can be explained by a model in which nondisjunctionis the consequence of the age-dependent movement of transposableelements. According to this model, nondisjunction is explainedas the consequence of the repair of transposon-induced breaksin the DNA. Both models provide reasonable alternatives to biologicallyimplausible explanations such as the production linehypothesis. 相似文献
33.
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
34.
Fibrositis: symptom frequency and criteria for diagnosis. An evaluation of 291 rheumatic disease patients and 58 normal individuals 总被引:2,自引:0,他引:2
We administered a 17-item symptom questionnaire modified from Campbell to 155 patients with fibrositis diagnosed at 3 centers, each using different criteria sets. A high degree of agreement in symptom proportions was found among centers. "Fibrositic" symptoms were also common in 136 patients with a variety of rheumatic diseases but not in the 58 normal individuals studied. Symptoms distinguished fibrositis patients from normals easily, but had insufficient specificity to distinguish them from other rheumatic disease patients. The tender point count better separated fibrositic and nonfibrositic patients than historical criteria. No combination of questions and tender point count performed better than the tender point count alone. 相似文献
35.
36.
37.
Stepto NK Hawley JA Dennis SC Hopkins WG 《Medicine and science in sports and exercise》1999,31(5):736-741
PURPOSE: We have investigated the effect of varying the intensity of interval training on 40-km time-trial performance in 20 male endurance cyclists (peak oxygen uptake 4.8+/-0.6 L x min(-1), mean +/- SD). METHODS: Cyclists performed a 25-kJ sprint test, an incremental test to determine peak aerobic power (PP) and a simulated 40-km time-trial on a Kingcycle ergometer. They were then randomly assigned to one of five types of interval-training session: 12x30 s at 175% PP, 12x60 s at 100% PP, 12x2 min at 90% PP, 8x4 min at 85% PP, or 4x8 min at 80% PP. Cyclists completed 6 sessions over 3 wk, in addition to their usual aerobic base training. All laboratory tests were then repeated. RESULTS: Performances in the time trial were highly reliable when controlled for training effects (coefficient of variation = 1.1%). The percent improvement in the time trial was modeled as a polynomial function of the rank order of the intensity of the training intervals, a procedure validated by simulation. The cubic trend was strong and statistically significant (overall correlation = 0.70, P = 0.005) and predicted greatest enhancement for the intervals performed at 85% PP (2.8%, 95% CI = 4.3-1.3%) and at 175% PP (2.4%, 95% CI = 4.0-0.7%). Intervals performed at 100% PP and 80% PP did not produce statistically significant enhancements of performance. Quadratic and linear trends were weak or insubstantial. CONCLUSIONS: Interval training with work bouts close to race-pace enhance 1-h endurance performance; work bouts at much higher intensity also appear to improve performance, possibly by a different mechanism. 相似文献
38.
Sablinski T Emery DW Monroy R Hawley RJ Xu Y Gianello P Lorf T Kozlowski T Bailin M Cooper DK Cosimi AB Sachs DH 《Transplantation》1999,67(7):972-977
BACKGROUND: Mixed allogeneic hematopoietic chimerism has previously been reliably achieved and shown to induce tolerance to fully MHC-mismatched allografts in mice and monkeys. However, the establishment of hematopoietic chimerism has been difficult to achieve in the discordant pig-to-primate xenogeneic model. METHODS: To address this issue, two cynomolgus monkeys were conditioned by whole body irradiation (total dose 300 cGy) 6 and 5 days before the infusion of pig bone marrow (BM). Monkey anti-pig natural antibodies were immunoadsorbed by extracorporeal perfusion of monkey blood through a pig liver, immediately before the intravenous infusion of porcine BM (day 0). Cyclosporine was administered for 4 weeks and 15-deoxyspergualin for 2 weeks. One monkey received recombinant pig cytokines (stem cell factor and interleukin 3) for 2 weeks, whereas the other received only saline as a control. RESULTS: Both monkeys recovered from pancytopenia within 4 weeks of whole body irradiation. Anti-pig IgM and IgG antibodies were successfully depleted by the liver perfusion but returned to pretreatment levels within 12-14 days. Methylcellulose colony assays at days 180 and 300 revealed that about 2% of the myeloid progenitors in the BM of the cytokine-treated recipient were of pig origin, whereas no chimerism was detected in the BM of the untreated control monkey at similar times. The chimeric animal was less responsive by mixed lymphocyte reaction to pig-specific stimulators than the control monkey and significantly hyporesponsive when compared with a monkey that had rejected a porcine kidney transplant. CONCLUSION: To our knowledge, this is the first report of long-term survival of discordant xenogeneic BM in a primate recipient. 相似文献
39.
Hawley CJ Ratnam S Pattinson HA Quick SJ Echlin D 《Journal of psychopharmacology (Oxford, England)》1996,10(3):241-245
Nineteen major depressed patients, resistant to previous pharmacotherapies, were treated by the addition of moclobemide (up to 600 mg/day) to paroxetine or fluoxetine (20 mg/day) for 6 weeks in an open study to assess the adverse events and tolerability. There were 77 emergent events, insomnia, headache, nausea and dizziness being the most common. Many events were rated as severe. The high rate of adverse events suggests that there may be clinically significant interactions between moclobemide and SSRIs. However, the uncontrolled data on effectiveness is encouraging and the combination deserves further attention as a strategy for treating intractable major depression. 相似文献
40.
Herzig KA Falk MC Jonsson JR Axelsen RA Griffin AD Hawley CM Rigby RJ Cobcroft R Nicol DL Powell EE Johnson DW 《Transplantation》2000,70(1):149-152
BACKGROUND: In this report we describe a malignant lymphoma of donor origin inadvertently transplanted into two renal allograft recipients, despite standard comprehensive donor screening. The successful clearance of the tumor from both patients and a novel method of surveillance are detailed. METHODS: Initial management consisted of withdrawal of immunosuppression to promote rejection of the allograft and the transplanted tumor in both patients, followed by graft removal. Peripheral blood microchimerism was assessed in both recipients using nested polymerase chain reaction to detect the DYZ3 gene on the Y chromosome (donor male, recipients female). RESULTS: Although microchimerism was detected on day 6 after transplantation and day 1 after explantation, repeat peripheral blood examination at 1, 3, and 6 months after explantation demonstrated no microchimerism. Both patients remain well at 12 months and have been relisted for transplantation. CONCLUSION: Despite inadvertent transplantation of a previously undiagnosed malignancy of donor origin, the recipients' immune response was able to eliminate donor tumor cells after the withdrawal of immunosuppression. Repeated surveillance of peripheral blood from both recipients, using a novel application of the technique of nested polymerase chain reaction to amplify donor DNA, demonstrated no persistence of donor cells, supporting effective eradication of the donor malignancy. 相似文献