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61.
62.
Conclusions Mandibulodiaphragmatic distance, measured on the portable anteroposterior chest radiograph and applied to the predictive equation developed in this study, is a strong tool for the prediction of in-hospital mortality that could find wide application in clinical practice and provide vital information for risk stratification and resource allocation in a wide variety of acutely ill patients.Over the years, I have been disconcerted by the volume of useless investigation that surfaces in some of our journals. Many of these are correlative studies that have little usefulness other than to pad the investigator's bibliography and to fill journal pages. To follow, you will find a tongue-in-cheek research paper written by Dr. George H. Lindbeck, a colleague of mine, which nicely illustrates this pseudoscientific phenomenon. I think you will enjoy the satire. Theodore E. Keats, M.D.  相似文献   
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64.
Changes in calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) at the motor endplates of botulinum toxin-paralysed rat muscles were investigated using immunohistochemistry. One day following toxin injection, a dramatic increase in CGRP-LI was detected at the motor endplates and within preterminal axons of the soleus and gastrocnemius muscles. The upregulation of CGRP-LI persisted throughout the period during which muscle fibres were paralysed and new neuromuscular junctions were being formed by the growing sprouts. Decline of CGRP-LI at the motor endplates coincided with clinical recovery. Both up- and down-regulation of CGRP-LI took place earlier in the soleus than in the gastrocnemius muscle. Up-regulation of CGRP-LI was also detected in a subpopulation of motor axons in the sciatic nerves and in the spinal motor neurons innervating the paralysed muscles. These results indicate that levels of CGRP are regulated, at least partly, by changes in the target innervation. They also suggest an important role for CGRP in the regenerative processes following muscle paralysis.  相似文献   
65.
Two patients with acutely thrombosed femorofemoral bypass grafts are presented. Recombinant human tissue-type plasminogen activator (rt-PA) was used successfully in thrombolysis of the occluded grafts. Utilizing a new technique the grafts were punctured directly and bolus doses of rt-PA administered.  相似文献   
66.
A 3.5-month-old white boy was born with meconium ileus, peritonitis, and jejunal atresia from cystic fibrosis. He subsequently developed unrelenting and severe extrahepatic biliary obstruction as demonstrated by liver biopsy showing periportal inflammation, cholestasis, and fibrosis. Surgical exploration confirmed the diagnosis of extrahepatic biliary obstruction by severely inspissated bile. A cholecystostomy tube was left in place. The cholestasis remained unresponsive to conservative medical therapy. The obstruction was relieved by hydrostatic infusion of 2% N-acetylcysteine into the biliary tree over a 6-day period. The child also received concurrently four i.v. injections of synthetic cholecystokinin. This therapeutic modality was thought to be both safe and effective.  相似文献   
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68.
The case of a 3-day-old infant with Beckwith-Wiedemann syndrome who required anesthetic care during closure of an abdominal wall defect is presented. Beckwith-Wiedemann syndrome comprises a constellation of clinical features, including macroglossia, macrosomia, omphalocele, visceromegaly, mild microcephaly, facial nevus flammeus, horizontal earlobe creases, and renal medullary dysplasia. Due to the high rate of omphalocele in this syndrome, anesthetic care is frequently required during the neonatal period. Many of these infants (greater than 50%) are born prematurely. Therefore, their anesthetic care may be further complicated by associated diseases of prematurity, such as hyaline membrane disease. Additional anesthetic implications of this syndrome relate to the occurrence and management of hypoglycemia and polycythemia. Careful intraoperative management of glucose homeostasis is particularly important, since eventual neurologic outcome and intelligence will be normal provided prolonged neonatal hypoglycemia is avoided. Preoperative evaluation of the cardiac and genitourinary system, including echocardiography and renal ultrasound, are recommended because of the frequent occurrence of associated anomalies with omphalocele.  相似文献   
69.
The ability of serum prostate specific antigen (PSA) and serum acid phosphatase (SAP) to identify skeletal spread was evaluated in untreated patients with prostatic cancer. Twenty patients with scintigraphic evidence of metastatic disease in bone (M1) at diagnosis were compared with 50 untreated patients in whom scans were repeatedly negative during long-term surveillance. Using the present laboratory upper limit of normal (ULN) of 3 iu/l, the sensitivity and specificity of SAP for M1 disease were 80 and 86% respectively. Stepwise discriminant analysis demonstrated that SAP was able to stage patients correctly (bone scan positive or negative) with 81% predictive accuracy at an optimum cut-off limit of 4.6 iu/l. By contrast, whilst PSA (Hybritech) was 100% sensitive for skeletal disease at 10 ng/ml--at the expense of poor (36%) specificity--analysis determined that an optimum cut-off limit of 58 ng/ml led to 79% predictive accuracy for disease in bone. It was concluded that PSA levels > 58 ng/ml are highly indicative of spread to the skeleton, even in the absence of radiological or scintigraphic evidence of metastases.  相似文献   
70.
OBJECTIVE: To identify predisposing factors associated with cardiac rhythm disturbances during the early post-pneumonectomy period (first 7 postoperative days). MATERIALS AND METHODS: During the study period (1995-1999), 259 pneumonectomies were performed for malignant (244 cases) or benign disease (15 cases). Postoperative monitoring of patients included continuous arterial pressure - rhythm monitoring and pulse oximetry. Cardiac rhythm disturbances during the intensive care unit stay were detected on the monitor screen and recorded with a 12-lead electrocardiogram. Cardiac rhythm disturbances associated with electrolytes or fluid balance abnormality, mediastinal deviation or surgical postoperative complications were excluded from the study. Age of patients, preexisting cardiac disease, side of pneumonectomy, intrapericardial procedures, stage of the malignant disease, expected postoperative FEV(1)<1200 ml, intraoperative transfusions of packed red cells, elevated right heart pressures, low postoperative serum magnesium levels and long operative times were considered as predisposing factors for the development of post-pneumonectomy cardiac rhythm disturbances. Statistical analysis has been made using logistic regression analysis, Student t-test and chi-square test. RESULTS: Cardiac rhythm disturbances were detected in 49 patients (18.91%). Atrial fibrillation/flutter (31 cases), supraventricular tachycardia (14 cases), and premature ventricular contractions (four cases) were the observed rhythm disturbances. Right pneumonectomy versus left pneumonectomy (P<0.0001) and intrapericardial pneumonectomy versus standard pneumonectomy (P<0.0001) were identified as strong predisposing factors for the establishment of post-pneumonectomy cardiac rhythm disturbances. Patients who established post-pneumonectomy cardiac rhythm disturbances had significantly higher (P=0.024) right ventricular systolic pressure (42.50+/-15.50 mmHg) when compared with patients who had postoperative sinus rhythm (29.07+/-7.71 mmHg) and had also longer operative times than patients who did not develop rhythm disturbances (P=0.015). Mortality rate in patients who developed post-pneumonectomy rhythm disturbances was 20.40%. CONCLUSIONS: Cardiac rhythm disturbances observed early after pneumonectomy are mainly of supraventricular origin, complicating right and intrapericardial pneumonectomies, patients with elevated right heart pressures and long operative times, and are associated with high mortality rates.  相似文献   
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