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151.
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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Summary A disease-oriented approach to the discovery of novel platinum anticancer drugs has been established through the setting up of parallel human ovarian-carcinoma cell lines and xenografts. The correlation between in vitro and in vivo antitumour activity was determined for four reference platinum agents (cisplatin, carboplatin, iproplatin and tetraplatin) in eight companion lines. Two methods of assessing antitumour effect were used in vitro (tritiated thymidine incorporation and sulforhodamine B staining) and three were applied in vivo [28-day treated/control (T/C) ratio, growth delay and specific growth delay]. In vitro, large differences in cytotoxicity across the cell lines were observed for each drug. This was also reflected in the xenografts for cisplatin and carboplatin and, to a lesser extent, for iproplatin. A correlation analysis of in vitro vs in vivo data revealed a high, statistically significant positive correlation for cisplatin and a strong positive correlation for carboplatin. However, for the two platinum(IV) drugs, the correlation was less good. In particular, tetraplatin was markedly less active in vivo (showing a general lack of activity against all of the tumour lines) than its in vitro potency against the cell lines predieted, resulting in poor correlation coefficients. These human tumour panels may be valuable for the elucidation of both cellular/molecular and corresponding in vivo pharmacological mechanisms of platinum drug resistance. Moreover, the HX/62 and SKOV-3 tumour lines, which exhibit a level of intrinsic resistance to the four reference agents both in vitro and in vivo (and which were derived from patients who had not received prior platinum therapy), represent particularly useful evaluation models for the discovery of novel broad-spectrum platinum drugs.This study was supported by grants to the Institute of Cancer Research from the Cancer Research Campaign and the Medical Research Council, the Johnson Matthey Technology Centre and Bristol Myers Squibb Oncology  相似文献   
154.
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   
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156.
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   
157.
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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159.
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   
160.
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