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Evan D. Kharasch Kiang-Teck Yeo Margaret A. Kenny David W. Amory 《Journal canadien d'anesthésie》1989,36(5):545-553
Atrial natriuretic factor (ANF) is a peptide released from the heart in response to atrial distension. This peptide causes diuresis, vasodilatation, decreased blood pressure, and antagonizes the renin-aldosterone and antidiuretic hormone neuraxes. The influence of cardiopulmonary bypass and cardiac surgery on the circulation and release of ANF is unknown. Plasma ANF concentrations were therefore determined in patients undergoing coronary artery revascularization (CABG) and mitral valve replacement (MVR). Peptide levels were unchanged following anaesthetic induction. Plasma ANF concentrations decreased significantly during hypothermic (less than or equal to 28 degrees C) cardiopulmonary bypass in both patient groups. After 60 minutes of cardiac bypass, ANF declined from (mean +/- SEM) 512 +/- 132 to 20 +/- 6 pg.ml-1 (P less than 0.05) during MVR, and from 178 +/- 41 to 110 +/- 48 pg.ml-1 during CABG (P less than 0.05). Rewarming during bypass was associated with an increase in ANF concentration in both groups. Heparin anticoagulation and protamine reversal had no effect on immunoreactive ANF levels. In patients undergoing CABG, there was a linear relationship between plasma ANF concentration (pg.ml-1) and right atrial pressure (mmHg) prior to cardiopulmonary bypass (r = 0.86, P less than 0.005). However, one and three hours after cardiopulmonary bypass there was no significant relationship between right atrial pressure and ANF plasma levels. These results suggest that reduction in plasma ANF concentration occurs during hypothermic cardiopulmonary bypass. Furthermore, the proportional relationship between atrial distension and circulating ANF concentration was altered following cardiac surgery. 相似文献
13.
C J Yeo K D Lillemoe A S Klein M J Zinner 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(8):1016-1018
Perforation of esophageal malignancy secondary to instrumentation is an uncommon but catastrophic complication. Esophageal perforation at the site of an obstructing esophageal malignancy precludes simple operative repair and mandates esophageal resection with reestablishment of gastro-intestinal tract continuity. In the past the standard surgical approach has involved transthoracic esophageal resection via thoracotomy. We have successfully treated four patients with perforated esophageal neoplasms by transhiatal esophagectomy and cervical esophagogastrostomy, thus avoiding thoracotomy in high-risk patients. We consider transhiatal esophagectomy an advantageous alternative in the management of selected cases of instrumental esophageal perforation adjacent to an esophageal malignancy. 相似文献
14.
S. J. Carbognin N. M. Solomon F. E. Yeo S. J. Swanson E. M. Bohen J. M. Koff S. G. Sabnis K. C. Abbott 《American journal of transplantation》2006,6(7):1746-1751
Interferon alpha (IFN-alpha) can be effective therapy for patients with chronic kidney disease who have chronic hepatitis C (HCV). However, acute allograft rejection has been reported in association with IFN-alpha following kidney transplantation, and therefore IFN therapy is recommended prior to, rather than after, kidney transplantation whenever feasible. The special case of repeat allograft recipients who contract HCV after the first transplantation presents special difficulties. This report features the case of a repeat allograft recipient who presented with neutropenic fevers after 5 months of pegylated IFN-alpha therapy, initiated 6 months following the functional loss of his third graft and the reinitiation of hemodialysis (HD). Physical exam, radiographic and laboratory findings led to allograft nephrectomy. The pathologic findings supported a diagnosis of acute-on-chronic rejection. This represents a rare case of IFN-alpha induced rejection following allograft failure and return to HD in a repeat allograft recipient. It also calls attention to the need for a high index of suspicion for the development of allograft rejection, which may require allograft nephrectomy even after allograft 'failure'. 相似文献
15.
The specificity and sensitivity of an indirect and two (an ‘ordinary’ and a ‘rapid’) double sandwich enzyme-linked immunosorbent assay (ELISA) procedures for the quantitation of Calloselasma rhodostoma (Malayan pit viper) venom were examined. The three assays were equally sensitive and the accuracy of the assays was not substantially affected by individual variation in the venom composition. The specificity of the assays was examined against 26 venoms from snakes of the families Viperidae and Elapidae. While the double sandwich ELISA procedures were sufficiently specific to be used in the clinical immunodiagnosis of C. rhodostoma bite in Malaysia, the indirect ELISA procedure exhibited extensive cross-reactivity with other Malaysian pit viper venoms. Attempts were made to improve the specificity of the indirect ELISA procedure for the quantitation of C. rhodostoma venom. A ‘low ELISA cross-reactivity’ venom fraction (termed VF52) was isolated from C. rhodostoma venom by repeated Sephadex G-100 gel filtration chromatography. The indirect ELISA procedure using antibodies to VF52 as immunoreagent showed an improvement in specificity. The use of the indirect ELISA procedure for the detection of C. rhodostoma antibodies was also examined and the results show that the assay was sufficiently specific to be used for retrospective diagnosis of C. rhodostoma bite in Malaysia, in particular when VF52 was used as the coating antigen. 相似文献
16.
Wilfred H. Manwaring 《The Journal of experimental medicine》1913,17(4):409-423
1. An extract of horse leucocytes is strongly bactericidal when dissolved in distilled water; it has considerable bactericidal power when dissolved in physiological saline; but it loses its bactericidal properties when mixed with blood serum or with normal or pathological tissue fluids. 2. About half the antibactericidal action of blood serum is due to the serum colloids, about a quarter to the neutral serum crystalloids, and a quarter to the diffusible alkalies. Diffusible acids have no antibactericidal action. 3. The addition of boric acid to an inactive mixture of leucocytic extract and serum or other body fluid occasionally restores part of the original bactericidal power, but never more than a small fraction of that power. 相似文献
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Steven C. Cunningham M.D. Farin Kamangar M.D. M.P.H. Min P. Kim M.D. Sommer Hammoud Raqeeb Haque Anirban Maitra M.B.B.S. Elizabeth Montgomery M.D. Richard E. Heitmiller M.D. F.A.C.S. Michael A. Choti M.D. F.A.C.S. Keith D. Lillemoe M.D. F.A.C.S. John L. Cameron M.D. F.A.C.S. F.R.C.S. F.R.C.S.I. Charles J. Yeo M.D. F.A.C.S. Richard D. Schulick M.D. F.A.C.S. 《Journal of gastrointestinal surgery》2005,9(5):718-725
Gastric adenocarcinoma is the second leading cause of cancer death worldwide. In Western series, survival rates vary widely
and are generally lower than those reported from Eastern series. We performed a retrospective analysis of cases operated on
at the Johns Hopkins Hospital over the past 18 years and collected data on demographics, tumor characteristics, pathologic
stage, treatment methods, complications, survival time, and other relevant factors. Survival according to stage of disease,
Lauren tumor type, tumorlocation,time period, andadministration of adjuvant therapy wasanalyzed, andresultswerecompared with
those of other Western series. During this period, 436 patients with gastric adenocarcinoma underwent resection. We have shown
a statistically significant association between survival and margin status, stage of disease, and Lauren tumor type. Overall
5-year survival was 26%, and 5-year survival after R0 resection was 33%. No significant difference was detected between survival
and tumor location, time period of treatment, or administration of adjuvant therapy. Analysis of various Western series reveals
major differences between the cohorts under study, such as stage of disease, extent of resection, tumor type, and tumor location.
Many of the reported differences among Western series may be due to cohort differences, such as stage of disease, extent of
resection, tumor type, and tumor location. 相似文献
20.
Susanna L. Matsen Charles J. Yeo Ralph H. Hruban Michael A. Choti 《Journal of gastrointestinal surgery》2005,9(2):270-279
Humoral hypercalcemia of malignancy is widely associated with tumor production of parathyroid hormone related protein (PTH-rP).
This peptide functions in endocrine, autocrine and paracrine mechanisms in a manner similar to PTH; increasing renal uptake
of calcium, decreasing retention of phosphorous, and stimulating adenylate cyclase and phospholipase C. Although PTH-rP production
has been well documented in neoplasms of the exocrine pancreas, we present here two cases of endocrine pancreatic neoplasms
elaborating PTH-rP. We then review the literature of previous cases and delve into the pathophysiology of this peptide. 相似文献