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81.
Jorge E. Zamora Ola P. Rosaeg M. Patrice Lindsay Mary Lou Crossan 《Journal canadien d'anesthésie》1996,43(4):347-352
Purpose
The efficacy of infusion of 0.5 L and 1.0 L Ringer’s lactate (LR) to prevent hypotension during induction of obstetric analgesia was studied. The effect of the different fluid boluses on fetal heart rate (FHR) and frequency of uterine contractions were also determined.Methods
Ninety-two ASA 1–2 parturients were randomized to receive 0.5 L (Group 1) and 1.0 L (Group 2) LR immediately before incremental epidural injections with lidocaine to achieve T10 sensory block. Systolic blood pressure (SBP) was measured with an automated BP cuff every two minutes for 30 min after infusion of fluid bolus. Fetal heart rate monitoring and tocometry were used continuously. The number of uterine contractions were recorded 30 min before and 60 min after iv bolus.Results
The SBP decreased in both groups, but there was no difference between groups in mean SBP or maternal heart rate. The incidence of hypotension (SBP < 90 mmHg or decrease of 20%) was 4% in both groups. The FHR record of a patient in Group 1 showed a single late deceleration, and a decrease in beat-to-beat variability occured in one patient in Group 2. A decrease in the frequency of uterine contractions of two or more contractions per 30 min was noted more frequently in Group 2 (P < 0.05). The duration of iv bolus was longer in Group 2 than Group 1 (18.8 ± 4.3 min vs 12.3 ± 4.5 min, P < 0.01).Conclusion
Administration of 1.0 L LR iv does not provide added protection against maternal hypotension, and is associated with delay in providing pain relief and a risk of decreasing uterine contraction frequency. 相似文献82.
83.
Two cases with acute myocardial infarction are presented. Both had thrombotic occlusion of the infarct-related artery. Following successful thrombolysis with streptokinase, coronary angiography was normal. These cases prove that "myocardial infarction with normal coronaries" can be associated with coronary thrombosis in the acute stage. 相似文献
84.
Jeri W. Nieves Felicia Cosman Chris Mars Robert Lindsay 《Calcified tissue international》1992,51(5):352-355
Summary Forearm bone mineral density (BMD) was measured at proximal and distal sites by 125I single photon absorptiometry (SPA) and by dual energy X-ray absorptiometry (DXA) in 67 consecutive subjects, aged 18–75 years. Correlations and regression equations between these two techniques were determined. All forearm measurements were significantly correlated with each other (r=0.599–0.926; P0.0001). Although SPA and DXA correct for fat in different ways, we found similar correlation and regression equations in women with body mass index measurements above and below the mean. In addition, forearm measurements by both techniques were moderately correlated with vertebral spine and hip BMD. We conclude that overall, SPA forearm measurements in a population can be calibrated to DXA measurements if necessary, and that DXA forearm measurements are as predictive of the remainder of the skeleton as SPA measurements. 相似文献
85.
J S Lindsay 《The New Zealand medical journal》1977,86(591):12-16
Analyses of hospital functioning are frequently reported with patient outcomes as the independent variable. However, the main focus in this paper is the length of stay in hospital not just in terms of "short stay" or "long stay", but ranked in tenths so that ten-point distributions of patient use of hospital resources are available for study. From the analysis of these distributions three patterns emerge: (a) a "standard procedure" model with best fitting "curves" given by a linear function, eg routine surgery; (b) a "finite disease" model (exponential series) eg internal medicine and, (c) a "person in hospital care" model (power series) eg psychiatry. 相似文献
86.
Severe injury or infection is associated with a hypermetabolic response that, when excessive, results in impaired wound healing
and as a consequence increased morbidity and mortality. The objective examination of wound healing in humans is difficult
and generally requires the use of models. Evidence is accumulating that nutritional and growth factors play important roles
in improving the wound healing response, particularly after thermal injury and uncomplicated major surgery. The septic patient
represents the biggest challenge to those seeking to optimize wound healing capacity. Advances in molecular biology have provided
promising therapies in experimental studies of wound healing that await clinical investigation. 相似文献
87.
Thomas Armstrong Graham Packham Lindsay B Murphy Adrian C Bateman John A Conti David R Fine Colin D Johnson R Christopher Benyon John P Iredale 《Clinical cancer research》2004,10(21):7427-7437
PURPOSE: The purpose of this study was to determine the role of functional interactions between pancreatic cancer cells and pancreatic stellate cells (PSCs) in the formation of the desmoplastic reaction (DR) in pancreatic cancer and to characterize the effect of type I collagen (the predominant component of the DR) on pancreatic cancer cell phenotype. EXPERIMENTAL DESIGN: PSCs and type I collagen were identified in sections of pancreatic cancer using immunohistochemistry, and their anatomic relationship was studied. Interactions among pancreatic cancer cell lines (MIA PaCa-2, Panc-1, and AsPC-1), primary cultures of human PSCs, and type I collagen were investigated in a series of tissue culture models. RESULTS: In vivo, the DR causes gross distortion of normal pancreas, bringing cancer cells into close contact with numerous PSCs and abundant type I collagen. In tissue culture models of pancreatic cancer, conditioned media from each cell line increased PSC [3H]thymidine incorporation up to 6.3-fold that of controls, and AsPC-1 cells also increased PSC collagen synthesis 1.3-fold. Type I collagen was observed to increase long-term survival of pancreatic cancer cells treated with 5-fluorouracil, by up to 62% in clonogenic assays. This was because type I collagen increased the proliferation of cancer cells ([3H]thymidine incorporation was up to 2.8-fold that of cells cultured on tissue culture plastic) and reduced apoptosis of AsPC-1 cells in response to 5-fluorouracil (by regulating mcl-1). CONCLUSIONS: These experiments elucidate a mechanism by which the DR in pancreatic cancer may form and, via the collagen within it, promote the malignant phenotype of pancreatic cancer cells, suggesting significant detriment to the host. 相似文献
88.
Claims regarding amnesia for childhood sexual abuse have often been based on studies of adults' responses to questions of the form, “Was there ever a period of time when you remembered less of the abuse than you do now?” In this experiment, 43 adult (mean age = 42) participants rated their current and prior memories of several nontraumatic childhood/adolescent events. Reports of prior periods of less memory were fairly common. Participants then engaged in “reminiscence” or “enhanced” retrieval activities directed toward remembering more about a selected target event. Following retrieval, 35% of the reminiscence condition participants reported prior poor memory for the target event, as did 70% of the enhanced condition. These results highlight the need for appropriate control conditions in retrospective studies of amnesia for childhood trauma. 相似文献
89.
90.
Truncated TrkB mediates the endocytosis and release of BDNF and neurotrophin-4/5 by rat astrocytes and schwann cells in vitro 总被引:3,自引:0,他引:3
Binding and cross-linking studies with radiolabeled neurotrophins demonstrate that cultured rat hippocampal astrocytes lack full-length TrkB, but do express high levels of truncated TrkB (tTrkB). In astrocytes and Schwann cells, tTrkB appears to have the novel function of mediating the endocytosis of neurotrophins into an acid-stable, Triton X-100 resistant intracellular pool that is released back into the medium in a temperature-dependent manner. Chloroquine treatment, trichloroacetic acid solubility, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed that when incubated with astrocytes or Schwann cells for at least 48 h neither the intracellular nor the released neurotrophins were significantly degraded. The endocytosis and release of neurotrophins may represent a novel mechanism whereby neuroglia can regulate the local concentration of these neurotrophic factors for extended periods of time. 相似文献