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61.
Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification are presented.  相似文献   
62.
AIM: A number of imaging techniques have been used for the pre-operative assessment of patients for lung volume reduction surgery (LVRS). We evaluated whether data currently acquired from perfusion scintigrams and cine MR of the diaphragm are obtainable from high resolution CT (HRCT) of the thorax. MATERIALS AND METHODS: Thirty patients taking part in a randomized controlled trial of LVRS against maximal medical therapy were evaluated. HRCT examinations (n= 30) were scored for (i) the extent and distribution of emphysema; (ii) the extent of normal pulmonary vasculature; and (iii) diaphragmatic contour, apparent defects and herniation. On scintigraphy, (n= 28), perfusion of the lower thirds of both lungs, as a proportion of total lung perfusion (LZ/T(PERF)), was expressed as a percentage of predicted values (derived from 10 normal control subjects). On cine MR (n= 25) hemidiaphragmatic excursion and coordination were recorded. RESULTS: Extensive emphysema was present on HRCT (60% +/- 13.2%). There was strong correlation between the extent of normal pulmonary vasculature on HRCT and on perfusion scanning (r(s)= 0.85, P< 0.00005). Hemidiaphragmatic incoordination on MR was weakly associated with hemidiaphragmatic eventration on HRCT (P= 0.04). CONCLUSION: The strong correlation between lung perfusion assessed by HRCT and lung perfusion on scintigraphy suggests that perfusion scintigraphy is superfluous in the pre-operative evaluation of patients with emphysema for LVRS.  相似文献   
63.

Table of Contents

Contents Volume 32 No. 1 (2000) Section One: International Urology and Nephrology  相似文献   
64.
Percutaneous nephrolithotripsy in ectopic kidneys   总被引:5,自引:0,他引:5  
BACKGROUND: Percutaneous nephrolithotomy (PCNL), although an accepted treatment modality in anatomically normal kidneys, is still not universally performed for calculi in pelvic ectopic kidneys. Fear of injury to abdominal viscera makes it a technically challenging procedure. PATIENTS AND METHODS: We have performed PCNL in nine patients with calculi in pelvic ectopic kidneys. Technical factors which made this procedure safe include ultrasound-guided puncture, use of a mature tract or an Amplatz sheath, routine postoperative double-J stenting, and nephrostogram prior to nephrostomy tube removal. RESULTS: Complete stone clearance was achieved in all cases. Six patients were treated in a single stage, while three patients required two stages. Seven patients needed only one tract, and two needed two tracts. No notable complications were encountered. The average hospital stay was 5.2 days. CONCLUSION: With proper precautions and meticulous technique, PCNL is a safe and effective modality to treat calculi in pelvic ectopic kidney.  相似文献   
65.
Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n  = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401)  相似文献   
66.
Surgery for Syringomyelia: An Analysis Based on 163 Surgical Cases   总被引:23,自引:0,他引:23  
Goel A  Desai K 《Acta neurochirurgica》2000,142(3):293-302
Summary ? Object. The authors analyzed the cases of 163 patients with syringomyelia to assess the appropriate surgical procedure. Methods. Depending on the aetiological factors and treatment considerations the series was classified into three groups. Group I were cases where there was no definite demonstrable aetiological factor; Group II cases had basilar invagination and/or Chiari malformation; and Group III consisted of cases where the syrinx was secondary to an obvious aetiology, such as a mass lesion either in the posterior cranial fossa or in the spine or a severe kyphotic spinal deformity. Post-traumatic syringomyelia and syrinx in association with spina bifida were not studied. Conclusions. We concluded that for Group I cases syringosubarachnoid shunting is the ideal form of treatment. In Group II cases foramen magnum bony decompression is satisfactory and physiological. Good results were obtained even in cases where either a foramen magnum decompression alone or in combination with a syringo-subarachnoid shunt was done. Only syringosubarachnoid shunt (without a foramen magnum decompression) in Group II cases was found to produce poor outcome. Group III cases should be treated for the primary aetiological problem. Only syrinx drainage procedure without treatment of aetiology in these cases produced poor results. It was observed that clinical outcome rather than radiological improvement is the reliable indicator of the surgical result.  相似文献   
67.
Gore DC  Ferrando A  Barnett J  Wolf SE  Desai M  Herndon DN  Goodwin C  Wolfe RR 《The Journal of trauma》2000,49(4):673-7; discussion 677-8
BACKGROUND: In critically ill patients, elevation in the plasma lactate concentration has traditionally been interpreted as indicating a deficiency in oxygen availability and is often an impetus to increase oxygen delivery clinically. However, another possible basis for increased lactate concentrations may be simply a mass effect from increased pyruvate availability (i.e., accelerated glycolysis). METHODS: In six hypermetabolic burned patients, the rates of glucose production and oxidation were quantified using a tracer infusion of 6,6 d2 glucose combined with indirect calorimetry. Measurements were obtained after a 9-hour fast and after a 3-hour infusion of unlabeled glucose at 30 micromol/kg/min. No patient was overtly septic, hypoxic, or hypovolemic. RESULTS: The infusion of glucose significantly increased the arterial glucose concentration and rate of glucose oxidation, with a corresponding increase in the arterial plasma concentration of lactate and pyruvate. Resting energy expenditure and oxygen consumption were not affected by the infusion of glucose. CONCLUSIONS: These findings show that elevations in plasma lactate in severely injured patients may, in part, be related to increases in glucose flux and not entirely a reflection of any deficit in oxygen availability. Such findings highlight a potential pitfall for interpreting plasma lactate concentrations as an index of tissue oxygen availability in hypermetabolic patients.  相似文献   
68.
69.
PURPOSE: To compare the preclinical and clinical pharmacokinetic properties of paclitaxel formulated as a Cremophor-free, albumin-bound nanoparticle (ABI-007) and formulated in Cremophor-ethanol (Taxol). EXPERIMENTAL DESIGN: ABI-007 and Taxol were given i.v. to Harlan Sprague-Dawley male rats to determine pharmacokinetic and drug disposition. Paclitaxel pharmacokinetic properties also were assessed in 27 patients with advanced solid tumors who were randomly assigned to treatment with ABI-007 (260 mg/m(2), 30 minutes; n = 14) or Taxol (175 mg/m(2), 3 hours; n = 13), with cycles repeated every 3 weeks. RESULTS: The volume of distribution at steady state and clearance for paclitaxel formulated as Cremophor-free nanoparticle ABI-007 were significantly greater than those for paclitaxel formulated with Cremophor (Taxol) in rats. Fecal excretion was the main elimination pathway with both formulations. Consistent with the preclinical data, paclitaxel clearance and volume of distribution were significantly higher for ABI-007 than for Taxol in humans [21.13 versus 14.76 L/h/m(2) (P = 0.048) and 663.8 versus 433.4 L/m(2) (P = 0.040), respectively]. CONCLUSIONS: Paclitaxel formulated as ABI-007 differs from paclitaxel formulated as Taxol, with a higher plasma clearance and a larger volume of distribution. This finding is consistent with the absence of paclitaxel-sequestering Cremophor micelles after administration of ABI-007. This unique property of ABI-007 could be important for its therapeutic effectiveness.  相似文献   
70.
Pseudomonas aeruginosa infections are attributed to its ability to form biofilms and are difficult to eliminate with antibiotic treatment. Biofilm formation is regulated by quorum sensing (QS), an intracellular bacterial communication mechanism that allows the activation of numerous virulence factors and secondary metabolites. Targeting the QS pathway is a potential approach that prevents QS-controlled phenotypes and biofilm formation. For the first time, the current work has identified antiquorum sensing activity in the partially purified four fractions from the hot ethyl acetate extract of Cassia fistula fruit pods. Of the four fractions, only fraction-1 gave decreased AHL activity; the phytoconstituents in this fraction were identified as rhein, 3-aminodibenzofuran, 5-(hydroxymethyl)-2-(dimethoxymethyl)furan, and dihydrorhodamine. Fraction-1 (1 mg ml−1) and rhein (0.15 mg ml−1) showed 63% and 42.7% reduction in short-chain AHL production, respectively, without hindering the bacterial growth. Fraction-1 inhibited QS-mediated extracellular virulence factors viz. protease, elastase, pyocyanin, and rhamnolipid (p < 0.05). Quantitative analysis of biofilm formation showed 77% & 62.4% reduction by fraction-1 (1 mg ml−1) and rhein (0.15 mg ml−1) respectively. Confocal laser microscopy (CLMS) & scanning electron microscopy (SEM) confirmed the reduction of biofilm formation in Pseudomonas aeruginosa upon treatment with fraction-1 and rhein. Moreover, the in vivo study displayed that fraction-1 and rhein (standard) significantly enhanced the survival of Caenorhabditis elegans by suppressing the potency of virulence factors of Pseudomonas aeruginosa. Quantitative real-time polymerase chain reaction results demonstrated the down-regulation of QS-related genes, lasI, lasR, rhlI, and rhlR. In addition, in silico analysis divulged that a component identified by GC-MS displayed a strong affinity towards LasI and LasR. These findings suggest that potent phytochemicals from fraction-1, including rhein, could serve as novel phytotherapeutics in controlling emerging infections of antibiotic-resistant bacterial pathogens like Pseudomonas aeruginosa.

Pseudomonas aeruginosa infections are attributed to its ability to form biofilms and are difficult to eliminate with antibiotic treatment.  相似文献   
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