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21.
AIM: The aim of this study was to evaluate the role of explorative laparoscopy to evaluate candidates for complete resection of peritoneal carcinomatosis (PC) combined with hyperthermic intraperitoneal chemotherapy (HIPC). METHODS: The database of the surgical department of the Institut Gustave Roussy was used to select 113 patients planned to undergo a maximal cytoreductive surgery combined with HIPC for PC between April 2001 and July 2003. Among them, 11 underwent an explorative laparoscopy because extent of the PC was insufficiently documented to evaluate its resectability. Patient records were retrospectively reviewed. RESULTS: Laparoscopic evaluation was successful in all 11 patients. The median operating time was 38 min (range 23-75 min). The laparoscopic examinations were well tolerated in all cases. The median length of hospital stay was 1.7 days. For three patients, the PC was as judge as unresectable. A complete resection of the PC combined with HIPC was performed in seven out of the eight patients with PC considered resectable at laparoscopy. One patient was diagnosed with more extensive disease than that as assessed by the evaluative laparoscopy. Of note, for 20% of the patients with straight away laparotomy, the complete cytoreduction was not possible. CONCLUSION: Laparoscopic scoring of peritoneal carcinomatosis is accurate to assess the complete resectability of PC in patients for which there is inadequate or contradictory information concerning disease extent.  相似文献   
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Because of structural differences between a synthetic graft and the natural artery, a graft would be expected to alter the haemodynamics of the vessel which is bypassed. To examine this, a segment of the lower descending thoracic aorta in six calves was removed and replaced with a Dacron graft. The gradients in pressure and flow across this segment were calculated from simultaneous measurements of pressure and flow made at both ends. From these, the longitudinal (Zl) and transverse (Zt) impedance of the segment was computed. In three animals pressure and flow were measured in the ascending aorta so that the systemic input impedance (Zi) could also be computed. Neither the magnitude nor phase of Zl was affected by the graft. However, the magnitude of Zt was approximately five times higher at all frequencies above DC following insertion of the graft. The characteristic impedance (Zo) was computed from Zl and Zt. Zo for the aortic segment remained approximately constant between 20 and 40 Pa X s X cm-3 for the first 10 harmonics. In contrast, Zo for the graft was strongly frequency dependent, and progressively increased in magnitude up through the tenth harmonic. The input impedance at the entrance to the segment (Zx) was strongly influenced by Zo. As a result, the higher frequency components of Zx were increased following insertion of the graft. In spite of these local changes in impedance, Zi was not affected by the graft. This was probably due to effective filtering by the healthy, compliant aorta left intact between the graft and the left ventricle.  相似文献   
24.
When the conduct, performance or health of a doctor in training is called into question, there is often confusion about the roles and responsibilities of the parties involved. Where does training stop and employment begin? When should poor performance trigger intensified training, and when should it lead to dismissal? How much information should be transferred from employer to employer as a trainee moves around a training programme? This article describes one Deanery's approach.  相似文献   
25.
The relative prognostic value of clinical heart failure and early M-mode and 2-dimensional echocardiographic indexes of left ventricular performance was compared in a study of 205 consecutive patients with acute myocardial infarction (AMI). Statistical analysis showed that an early wall motion score was a stronger predictor of 1-year mortality than the occurrence of clinical heart failure early, late or at any time during the hospital course of AMI. The finding of clinical heart failure had an independent prognostic value of intermediate strength. M-mode echocardiographic parameters only had a weak independent prognostic value, possibly related to their content of information on left ventricular end-systolic dimension.  相似文献   
26.
To develop improved prognostic algorithms for routine bedside use in acute myocardial infarction (AMI), the prognostic value concerning 2- and 12-month mortality of an early (within 72 hours after AMI) resting echocardiogram was defined in 201 consecutive patients. The relation between (1) the clinical variables (age, sex, prior and repeat AMI, arrhythmias, cardiac arrest, early [less than 72 hours after AMI] and late heart failure, early and maximal in-hospital Killip class, and maximal creatine kinase-MB isoenzyme), (2) early myocardial performance by echocardiography, and (3) mortality was characterized by Kaplan-Meier survival curves and receiver-operating characteristic curves based on Cox regression model. Only age and clinical heart failure in terms of the maximal in-hospital Killip class had independent predictive value of death (p less than 0.05) when an early echocardiographic estimate of left ventricular ejection fraction (LVEF) was included in the multivariate statistical models. The following 2 optimized algorithms for admission and predischarge calculation of risk of mortality at 2 and 12 months were developed based on the Cox model, using combinations of age, maximal Killip class and early echocardiographic LVEF: mortality at 2 months = 1 - exp - [0.051 x exp [0.044 x (age -60) - (0.117 x (LVEF - 40)]]; and mortality at 1 year = 1 - exp - [0.101 x exp [0.408 x (maxKillip - 1) - (0.061 x (LVEF - 40)]]. Discriminative power for prediction of mortality of the predischarge algorithm in an independent population of 195 patients 5 days after AMI compared favorably with that obtained in the original population, confirming the validity of the proposed method of prognostication.  相似文献   
27.
Capsule endoscopy represents a significant advance in the investigation of small bowel diseases and the beginning of wireless endoscopic imaging. Capsule endoscopy involves swallowing a video capsule endoscope, which is painless and relatively safe. Its use has been established for suspected small bowel bleeding, and the role of capsule endoscopy in the investigation of inflammatory bowel disease, iatrogenic disease, polyposis syndromes and coeliac disease is evolving. It is likely that in many instances it will become the next test after standard endoscopic evaluation. Early data suggest that capsule endoscopy improves outcome in patients with suspected small bowel bleeding, but more data are required on outcomes for the other indications.  相似文献   
28.
Poly(lactide-co-glycolide) (PLGA) has been widely used for bone tissue regeneration. However, it lacks hydrophilicity, bioactivity and sufficient mechanical strength and its acidic degradation by-products can lead to pH decrease in the vicinity of the implants. Mesoporous bioactive glass (MBG) with highly ordered structure (pore size 2–50 nm) possesses higher bioactivity than non-mesoporous bioactive glass (BG). The aim of this study is to investigate the effect of MBG on the mechanical strength, in vitro degradation, bioactivity, cellular response and drug release of PLGA films and optimize their physicochemical, biological and drug-delivery properties for bone tissue engineering application. The surface and inner microstructure, mechanical strength and surface hydrophilicity of MBG/PLGA and BG/PLGA films were tested. Results indicated that MBG or BG was uniformly dispersed in the PLGA films. The incorporation of MBG into PLGA films significantly improved their tensile strength, modulus and surface hydrophilicity. MBG/PLGA resulted in an enhanced mechanical strength, in vitro degradation (water absorbance, weight loss and ions release), apatite-formation ability and pH stability in simulated body fluids (SBF), compared to BG/PLGA. MBG/PLGA and BG/PLGA films enhanced human osteoblastic-like cells (HOBs) attachment, spreading and proliferation compared to PLGA. HOBs differentiation was significantly upregulated when cells were cultured on 30 MBG/PLGA for 14 days, compared to 30 BG/PLGA. MBG/PLGA enhanced the accumulative release of dexamethazone (DEX) at early stages (0–200 h) compared to BG/PLGA, however, after 200 h, DEX-release rates for MBG/PLGA was slower than that of BG/PLGA. The contents of MBG in PLGA films can control the amount of DEX released. Taken together, MBG/PLGA films possessed excellent physicochemical, biological and drug-release properties, indicating their potential application for bone tissue engineering by designing 3D scaffolds according to their corresponding compositions.  相似文献   
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30.
The distribution of enterokinase in human intestine was studied in operative mucosal biopsies using specific antiserum to human enterokinase, previously purified to apparent homogeneity by affinity chromatography and immunoabsorption. Fluorescence was observed in the brush-border and glycocalyx of the duodenum and proximal 15 cm of jejunum distal to the D/J flexure. Distal jejunum and ileum as well as stomach and colon were consistently negative. Brunner's glands and goblet cells were never stained by specific antibody. Preliminary evidence was obtained that the human enterokinase molecule contains a specific antigenic determinant in its polypeptide component and a second determinant in the oligosaccharide moiety which cross-reacts with blood group A. Preliminary evidence was also obtained that mucosal synthesis of enterokinase may be impaired in jaundice due to carcinoma of the pancreas and induced in the small intestine distal to the normal limit of synthesis after pancreatico-duodenectomy.  相似文献   
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