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41.
The present study represents a comprehensive retrospective review of endocarditis in a large district general hospital since the inception of a formalized policy involving collaborative management a decade ago. The principle was to involve a recognised team of cardiologists, specialists in infectious disease and microbiologists in the treatment of the disease from the moment of its diagnosis. The pattern of infection has not altered in terms of prevalent organisms and valves infected since the change in management policy. There has, however, been a significant decline in the mortality, from 34 to 24% for all patients with endocarditis. Amongst those referred for collaborative management, the mortality has fallen to 6%. The single greatest improvement is a reduction in the number of patients dying of heart failure, the number of patients developing systemic emboli or requiring prosthetic valve replacement remaining unchanged. The results indicate that early referral to, and treatment by, a multidisciplinary team can significantly reduce the mortality from bacterial endocarditis. 相似文献
42.
In some instances the same electrodes are used for stimulation and then for recording a bioelectric event immediately after
the stimulus. However, after the current pulse there remains an electrode potential that decays quasiexponentially. We have
designated this falling potential the electrode-recovery potential. This study investigated the recovery potentials of single
electrodes of rhodium, stainless steel, platinum and platinum-iridium in contact with 0.9% saline at room temperature (25°C)
over a current density ranging from 0.1 to 100 mA/cm2 using a constant-current pulse. In all cases, with increasing current density, there was a decrease in the time for the electrode
potential to fall to one half of the immediate post-stimulus value. Above about 20 mA/cm2 the decrease in recovery time was smooth with increasing current density. Below 20 mA/cm2, the recovery time was slightly irregular. The shortest recovery times were for platinum and platinum-iridium. The largest
decrease in recovery time with increasing current density was for stainless steel, which decreased 10 fold from 0.1 to 100
mA/cm2. The recovery time for rhodium decreased about three-and-one half fold over the same current density range. It was found
that the waveform of the recovery potential is not a simple exponential because the Warburg and Faradic components of the
electrode-electrolyte interface are current-density dependent. In general, for all current densities studied (0.1–100 mA/cm2), there was a sudden initial fall in electrode potential with cessation of current flow, followed by a very gradual nonexponential
decrease in potential. 相似文献
43.
1. The basic defect in cystic fibrosis relates to abnormalities of ion transport in affected tissues, such as the respiratory and gastrointestinal tracts. The identification of the cystic fibrosis gene has enabled studies on the production of a cystic fibrosis transgenic mouse to be undertaken. Knowledge of normal ion transport will be necessary for the validation of any such animal model. We have therefore characterized selected responses of the murine trachea and caecum mounted in 'mini' Ussing chambers under open-circuit conditions. 2. Basal values for the trachea were: potential difference, 1.1 mV (SEM 0.2; n = 18); equivalent short-circuit current, 20.4 microA/cm2 (3.6); conductance, 18.2 mS/cm2 (1.7). Corresponding values for the caecum were: potential difference, 0.7 mV (0.1; n = 18); equivalent short-circuit current, 11.0 microA/cm2 (1.6); conductance, 14.5 mS/cm2 (1.4). 3. Amiloride (10 mumol/l) produced a significant (P less than 0.001) fall in potential difference of 43.0% (5.7) in the trachea, but had no significant effect in the caecum. 4. Subsequently, one of three protocols was used to assess the capacity of either tissue for chloride secretion. Addition of a combination of forskolin (1 mumol/l) and zardaverine (10 mumol/l) produced rises in the potential difference of 873% (509) in the trachea and 399% (202) in the caecum. Both A23187 (10 mumol/l) and phorbol dibutyrate (10 nmol/l) increased tracheal potential difference by 350% (182) and 147% (47), respectively. Neither had a significant effect in the caecum. 5. Subsequent addition of bumetanide caused a fall in the stimulated potential difference of between 39.8% and 71.7%, depending on secretagogue and tissue type.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
44.
45.
Michelle Lucinda DeOliveira M.D. Tarcisio Triviño M.D. Ph.D. Gaspar de Jesus Lopes Filho M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(8):1140-1143
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies.
Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable
than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor,
although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis
of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance
and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with
final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison
was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy
were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although
preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value
of the endoscopic appearance was superior to endoscopic biopsy in this series.
Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003.
Supported by FADA-CAPES/PROP 200J (M.L.D.). 相似文献
46.
47.
Jonathan D Schiff Michelle L Ramírez Natan Bar-Chama 《Endocrinology & Metabolism Clinics of North America》2007,36(2):313-331
Male infertility is the result of a variety of highly treatable conditions. The critical step in treating male infertility is to evaluate properly every male partner of an infertile couple and to generate the proper treatment strategy. There are many medical and surgical options that can help most couples overcome male factor infertility. Male infertility can most easily be broken down into problems of sperm production (testicular dysfunction) and problems of sperm transport (obstruction). When applicable, medical therapies are used as an initial strategy to improve sperm production or as a preliminary therapy to boost production transiently in anticipation of a surgical sperm retrieval attempt. A range of surgical options is available to correct varicoceles, reconstruct the obstructed system, or retrieve sperm for assisted reproduction. 相似文献
48.
49.
Michelle D Williams Ehab Y Hanna Adel K El-Naggar 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(1):72-75
A rare case of anaplastic ameloblastic fibrosarcoma (AS) arising in an ameloblastic fibroma (AF) of the maxilla of a 48-year-old patient 10 years after the primary excision is presented. The recurrent tumor retained focal areas of AF but manifested heterogeneous malignant features ranging from low-grade spindle to highly pleomorphic sarcomas. Biomarker analysis showed alterations of the p53 and c-KIT genes restricted to the sarcomatous component. The biological implications of these findings in the future management of these tumors are discussed. 相似文献