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121.
Management of critically ill patients is based on knowledge of fundamental physiological variables. Automatized and continuous measurement of these variables is preferable. A new system based upon the thermodilution method has been developed to measure cardiac output automatically and continuously. We evaluated the system in the potentially unstable perioperative period with possible great and rapid changes in cardiac output. Twenty patients, scheduled for open heart or abdominal aortic aneurysm surgery, were included into the study, which was approved by the local ethical committee. The patients were monitored for up to 30 hours. At random intervals five iced bolus thermodilution cardiac output (BCO) determinations were made and compared to the continuous measurements (CCO). Two hundred and thirty-one pairs of data were obtained. The cardiac outputs ranged from 2.5-14.9 l/min. The absolute bias was 0.31 l/min (95% limits of agreement -1.4 l/min to 2.0 l/min). The mean relative error was 4.7% with a standard deviation of the relative error of 15.4%. The linear regression was represented by: CCO = 11.352 x BCO - 0.36. The correlation coefficient R was 0.90 (p < 0.001). In conclusion, the CCO measurement technique is a promising clinical method. The method is straightforward, requires no calibration, is independent of vascular geometry and measures with its limitations volumetric flow. Finally automatic and continuous patient monitoring provides more information and has potential to reveal previously undetected haemodynamic events. 相似文献
122.
LJ van 't Veer MJ van der Feltz CA van den Berg-Bakker NC Cheng RP Hermens DA van Oorschot T Kievits PI Schrier 《Canadian Metallurgical Quarterly》1993,8(10):2673-2681
We have shown previously that mouse NIH3T3 cells transfected with DNA from a human ovarian carcinoma were rendered tumourigenic by an activated mas oncogene in four independent transfection experiments. In all cases the 5'-noncoding region was rearranged in comparison to the original ovarian tumour DNA. We now report that in all four transfectants the newly acquired sequences consist of human centromeric alpha satellite repeat DNA. In at least three transfectants the alphoid DNA originates from the centromere of chromosome three. Analysis of the sequences of the recombination site in one transfectant revealed that a homologous sequence of five base pairs (CAGCA) is present in both parental strands, and might thus have contributed to the recombinational event. To establish a conclusive role for alphoid DNA in the activation of mas, we performed a co-transfection experiment in NIH3T3 cells with cloned alphoid DNA and the mas coding sequence. We show that the transfectants expressing a transformed phenotype contain amplified mas linked to alphoid DNA. NIH3T3 cells transfected with plasmids that contained alphoid sequences cloned directly upstream of the mas coding sequence, and injected into nude mice, gave rise to tumours with amplified mas sequences (7/7). In six of these tumours the alphoid sequences were amplified as well. Our data suggest a novel mechanism of oncogene activation: recombination with normal alphoid repeat DNA resulting in amplification of the oncogene. 相似文献
123.
While it is generally recognized that NPs offer affordable, quality health care, few studies have measured outcomes of clients who seek primary care services from NPs. This pilot study describes the outcomes of children with otitis media who received care from NPs employed in an academic nursing center. Outcome measurements included issues related to timing, level of analysis, and attribution. Parents of 27 children participated in a telephone survey consisting of seven questions relating to the care their children received from NPs and their recovery path. Although every respondent reported having a positive visit at the nursing center, concerns for NPs surfaced during the process of measuring outcomes. This study emphasizes the need for measuring outcomes in nursing clinics and demonstrates one way to measures client outcomes, revealing both general health care and specific nursing practice implications. 相似文献
124.
DE Van Raemdonck NC Jannis PR De Leyn WJ Flameng TE Lerut 《Canadian Metallurgical Quarterly》1998,228(6):788-796
OBJECTIVE: To determine the length of warm ischemic tolerance in pulmonary grafts from non-heart-beating donors. SUMMARY BACKGROUND DATA: If lungs could be retrieved for transplant after circulatory arrest, the shortage of donors might be significantly alleviated. Great concern, however, exists about the length of tolerable warm ischemia before cold preservation of pulmonary grafts retrieved from such non-heart-beating donors. METHODS: The authors compared the influence of an increasing postmortem interval on graft function in an isolated, room air-ventilated rabbit lung model during blood reperfusion up to 4 hours. Four groups of cadavers (four animals per group) were studied. In group 1, lungs were immediately reperfused. In the other groups, cadavers with lungs deflated were left at room temperature for 1 hour (group 2), 2 hours (group 3), or 4 hours (group 4). RESULTS: Pulmonary vascular resistance was enhanced in all ischemic groups compared with the control group. An increase was noted with longer postmortem intervals in peak airway pressure and in weight gain. A concomitant decline was observed in the venoarterial oxygen pressure gradient caused by progressive edema formation, as reflected by the wet-to-dry weight ratio at the end of reperfusion. CONCLUSIONS: Warm ischemia resulted in increased pulmonary vascular resistance. Graft function in lungs retrieved 1 hour after death was not significantly worse than in nonischemic lungs. Therefore, 60 minutes of warm ischemia with the lung collapsed may be tolerated before cold storage. Further studies are necessary to investigate whether lungs retrieved from non-heart-beating donors will become a realistic alternative for transplant. 相似文献
125.
RJ Mullins NC Mann JR Hedges W Worrall GJ Jurkovich 《Canadian Metallurgical Quarterly》1998,44(4):609-16; discussion 617
BACKGROUND: Implementation of Oregon's trauma system was associated with a reduction in the risk of death for hospitalized injured patients. An alternative explanation for improved outcome, however, is favorable concurrent temporal trends, e.g., new technologies and treatments. PATIENTS AND METHODS: To control for temporal trends, seriously injured hospitalized patients in Oregon and Washington were compared before either state had a trauma system (1985-1988) and when only the Oregon trauma system had been implemented (1990-1993). The study group consisted of hospitalized injured patients aged 16 to 79 years with one or more index injuries in six body regions, i.e., head, chest, spleen/liver, femur or pelvis fracture, and burns. Hospital discharge claims data were analyzed, converting International Classification of Diseases, Ninth Revision, Clinical Modification, discharge diagnosis codes to Abbreviated Injury Scale scores and Injury Severity Scores using a conversion algorithm. Multivariate logistic regression models were used to estimate the differential risk-adjusted odds of death in Oregon compared with Washington after adjustment for demographics, injury type, and injury severity. RESULTS: Findings indicated no difference in the risk-adjusted odds of death between Oregon and Washington while both states functioned under an ad hoc trauma system (1985-1988). A significant reduction in the risk of death, however, was noted in Oregon for patients with an index injury and an Injury Severity Score > 15 compared with Washington (adjusted odds ratio (OR) = 0.80, 95% confidence interval (CI) = 0.70-0.91) after trauma system implementation in Oregon (1990-1993). Specifically, reductions in the risk of death were demonstrated for patients with head injuries (adjusted OR = 0.70, 95% CI = 0.59-0.82) or liver/spleen injuries (adjusted OR = 0.73, 95% CI = 0.54-0.99). CONCLUSION: Assuming that the two states demonstrated similar concurrent temporal trends, the findings support the conclusion that improved outcomes among injured patients in Oregon may be attributed to the institution of a statewide trauma system. 相似文献
126.
Pulmonary interstitial emphysema is a well-documented complication of positive-pressure ventilation. However, the occurrence of large sub-pleural air cysts is a less well-known, extreme manifestation of this entity. We present here an infant who developed this complication of pulmonary barotrauma during cardiopulmonary resuscitative efforts. 相似文献
127.
128.
The perireticular nucleus is a recently described thin sheet of small cells among the fibres of the internal capsule, lying lateral to the thalamic reticular nucleus and medial to the globus pallidus (Clemence and Mitrofanis [1992]. J. Comp. Neurol. 322:167-180). During development, the perireticular nucleus is relatively large, lying in the path of the growing corticofugal and thalamocortical axons and filling the area of the internal capsule lateral to the thalamic reticular nucleus. After these axons have formed their connections, the perireticular nucleus rapidly decreases in size, leaving only a few cells in the adult (Mitrofanis [1992] J. Comp. Neurol. 320:161-181). In this study, we aimed to investigate the connections between the developing cortex and thalamus by making injections of tracer into the cortical plate. Injections of Horse Radish Peroxidase (HRP), Wheat Germ Agglutinin bound to HRP (WGA-HRP) and 1'dioctadecyl-3,3,3',3 tetramethycarbocyanine perchlorate (DiI) were made in vivo between embryonic day (E) 18 and adult and DiI was placed in the fixed brains of rats aged between E16 and postnatal day (P)1. Between E17 and P10, the retrograde perikaryal labelling resulting from these injections revealed a transient projection from the perireticular nucleus to the ipsilateral cortical plate. No cells were labelled in the thalamic reticular nucleus. This suggests that the perireticular nucleus must be regarded as a group of cells distinct from the thalamic reticular nucleus and having a separate role in development. Comparisons between the perireticular cells and the cells of the cortical subplate suggest that both may be playing comparable roles in early development, possibly guiding fibres towards their end stations or serving to rearrange the complex mapped projections linking the thalamus and cortex. 相似文献
129.
A retrospective study to determine the effect of extranodal axillary disease on prognosis in invasive carcinoma of the breast was undertaken in a series of 152 cases. It was found that extranodal disease has an unfavorable effect on prognosis in those patients with three or less involved axillary nodes and no effect on prognosis in those patients with four or more involved axillary nodes. Extranodal axillary disease was found to have no influence on the interval between surgery and initial recurrence nor on the anatomic distribution of the recurrence, local or remote. 相似文献
130.
The application of roller-bottle cell culture techniques and a relatively simple purification scheme has led to the isolation of milligram quantities of a polypeptide cell multiplication stimulating activity (MSA) from Buffalo rat liver cell conditioned medium. We have characterized the apparently homogeneous MSA with respect to its biological activity, its N-terminal amino acid residue, and its amino acid composition, and have tested the MSA for growth-promoting activity in a number of cell types. 相似文献