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排序方式: 共有705条查询结果,搜索用时 15 毫秒
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Effect of pneumoperitoneal pressure on tumor dissemination and tumor recurrence at port-site and midline incisions 总被引:16,自引:0,他引:16
Moreira H Yamaguchi T Wexner S Singer L Zhao R Baig MK Mack JA Xiong H Abramson S 《The American surgeon》2001,67(4):369-373
Over the past several years numerous cases of port site tumor recurrence after laparoscopic resection of a cancerous tissue have been reported. Possible mechanisms for tumor seeding include tumor removal, contaminated instruments, pneumoperitoneum, and aerosolization of tumor cells. This experiment examined the relationship among trocar contamination, aerosolization, and tumor recurrence with increasing pneumoperitoneal pressure using a hamster model. Increased pneumoperitoneal pressure significantly increased both instrument contamination and tumor recurrence at midline and port site incisions. Interestingly, increasing pneumoperitoneal pressure had no significant effect on the number of aerosolized tumor cells. The results reaffirm that the use of a reduced pneumoperitoneum or gasless laparoscopy may significantly lower port site tumor recurrence. 相似文献
33.
Rajesh P Rajesh R Narayanan V Baig MF Prabhu VR Venkatesan A 《Journal of the Indian Society of Pedodontics and Preventive Dentistry》2000,18(4):147-150
Cleft lip and palate is one of the most common malformations in man. Although the subject of a great deal of investigation, etiologic factors contributing to these congenital deformities remain largely unknown. Various factors like race, sex, parental age at the time of conception etc. have been listed as the exogenous factors. This article strives to project any significant relationship of these factors to cleft lip and cleft palate. 相似文献
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The purpose of this study was to use the concept of metastable equilibrium solubility (MES) to describe the anomalous solubility behavior of carbonated apatite (CAP) in the presence of solution strontium. A CAP sample (4.8 wt% CO(3), synthesized at 70 degrees C) was prepared by precipitation. Baseline MES distributions were determined in a series of 0.1 M acetate buffers containing only calcium and phosphate (no strontium) over a broad range of solution conditions. In order to assess the influence of strontium, MES profiles were then determined in a similar fashion with 20, 30, 40, 50, 60, 70, and 80% of the solution calcium being replaced on an equal molar basis by solution strontium. From the compositions of the equilibrating buffer solutions, ion activity products (IAPs) of the form Ca(10-n)Sr(n)(PO(4))(6)(OH)(2) (n = 0-10) were calculated in an attempt to determine the correct function governing the dissolution of the CAP preparation. The results demonstrate the following important findings: (a) at high solution strontium/calcium ratios (i.e., when 60% or more of the solution calcium was replaced by strontium), the MES profiles in all the experiments were found to be essentially superimposable when the solution IAPs were calculated using the stoichiometry of Ca(6)Sr(4)(PO(4))(6)(OH)(2), and (b), at low solution strontium/calcium ratios (i.e., when 40% or less of the solution calcium was replaced by strontium), the stoichiometry yielding MES data superpositioning was found to be that of hydroxyapatite. When other stoichiometries were assumed, good superpositioning of the data was not possible. 相似文献
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Epidemiological studies of workers in weaving units in carpet industries have shown relationships between the airborne dust concentrations and pulmonary ill health. Therefore, to predict the health risk of carpet weavers, this preliminary experiment was conducted to evaluate the effect of carpet dust (knotted, tufted) on cellular and biochemical mediators considered as potential biological markers of lung injury. Lung cytoplasmic (lactate dehydrogenase, LDH), lysosomal (acid phosphatase, ACP), type II (alkaline phoshatase, ALP) and Clara-cell marker enzymes (gamma-glutamyl transferase, GGT) were monitored in rat cell-free lung lavage (BAL) during postexposure days 1, 4, 8, and 16. Furthermore, lung microsomal cytochrome P-450 (CYP450) and Clara-cell secretory protein (CC16) content in BAL was also evaluated. These pulmonary marker enzymes were significantly elevated during the postexposure period over the respective untreated control; however, tufted carpet dust shows more responses than knotted carpet dust. Lung CYP450 content was reduced significantly at early days; the pattern shows the reoccurrence of CYP450 content in the later stage of postexposure to carpet dust. Clara-cell secretory protein in BAL shows decline in the carpet-treated group; however, tufted carpet shows more decline than knotted carpet. Thus, reduction in CC16 level may have important implication in the development of chronic lung inflammation and diseases. Present investigation found that modulation of these cellular marker enzymes is clear evidence of pulmonary damage caused by exposure to carpet dust. 相似文献
39.
Role of antimicrobials in third molar surgery: prospective, double blind,randomized, placebo-controlled clinical study 总被引:3,自引:0,他引:3
Sekhar CH Narayanan V Baig MF 《The British journal of oral & maxillofacial surgery》2001,39(2):134-137
AIM: To test the efficacy of two dosing regimens of antimicrobial prophylaxis during the removal of impacted lower third molars. DESIGN: Double blind, prospective, placebo-controlled trial. SETTING: Teaching hospital, India. SUBJECTS: 151 patients aged 19-36 having impacted lower third molars removed. METHODS: Random allocation into three groups: placebo (n= 34), metronidazole 1g orally, 1 hour preoperatively (n= 44), or metronidazole 400mg orally eight hourly for 5 days postoperatively (n= 47). Patients were recalled on the sixth postoperative day for assessment of pain scores on the second and sixth days, swelling, differences in mouth opening between preoperative and the sixth postoperative day, and the state of the wound. RESULTS: There were no significant differences in the outcome between the three groups (P= 0.09). CONCLUSION: Antimicrobial prophylaxis does not seem to reduce morbidity after removal of lower third molars. 相似文献
40.
An essential element in the control of tuberculosis is the rapid, sensitive and specific identification of the causative agent. Until now, screening and diagnosis are largely based on clinical signs, radiological examination, tuberculin tests, sputum examination under the microscope, or culture for mycobacteria. Tuberculin tests lack specificity and only give an indication of previous exposure to mycobacteria. Direct microscopic examination of sputum is neither specific nor sensitive enough, and mycobacterial isolation is time-consuming. As an alternative to these classical methods, new nucleic acid-based technologies show promise as a more rapid, sensitive, and specific means of identification of mycobacteria. Two commercial standardized nucleic acid-based amplification techniques have been reported to yield reliable results within 5 to 7 hrs. Roche Amplicor MTB (Roche Diagnostic System, Somerville, N.J.) and Gen-Probe AMTB (Gen-Probe Inc., San Diego, Calif.). The amplified target is part of the 16S rRNA gene which is common to all the mycobacteria. An attempt has been made to describe the use of the target DNA, SenX3-RegX3, in a multiplex PCR to detect and differentiate M. tuberculosis from other mycobacteria directly from clinical specimens. 相似文献