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71.
A case of Fournier's gangrene of the scrotum is reported in a 31-year old man who had outpatient vasectomy during an intercurrent diarrheal illness. The surgery was done through a midline incision, under local anesthesia of plain 2% lignocaine, with a preoperative chlorhexidine scrub. Although his scrotum was red and swollen within 3 hours, he did not have medical care until admission to hospital 48 hours later. At admission he had Fournier's gangrene of the scrotum and penis, Gram-negative septic shock, and acute renal failure. In the intensive care unit he was treated with continuous dialysis, parenteral metronidazole, benzylpenicillin, Ceftazidime and inotropes. He had a cardiorespiratory arrest after emergency radical debridement. After resuscitation he developed adult respiratory distress syndrome and disseminated intravascular coagulation. Pathological exam showed necrosis of the dermis and subcutaneous layers, thrombosis and beta-hemolytic streptococci. After adding gentamicin and vancomycin, 2 weeks of ventilator care, 4 more surgical debridements, a left orchidectomy, and a despite a grossly abnormal EEG recording, the man regained consciousness and recovered. His scrotal and penile skin re-epithelialized over 3 months. Patients requesting vasectomy should be assessed for local and systemic illness before performing the procedure.  相似文献   
72.
Trigger fingers and thumb: when to splint, inject, or operate.   总被引:5,自引:0,他引:5  
Fifty trigger fingers were treated by splinting of the metacarpophalangeal joint at 10 to 15 degrees of flexion for an average of 6 weeks (range, 3 to 9 weeks). Another 50 trigger fingers were injected with 0.5 ml of betamethasone sodium phosphate and acetate suspension (Celestone) and 0.5 ml of lidocaine. All patients were followed up for a minimum of 1 year (range, 1 to 4 years). Treatment was successful in 33 (66%) of the splinted digits and 42 (84%) of the injected digits. Fifty percent of the 10 splinted thumbs and 70% of the 40 splinted fingers had a successful outcome. Of the 17 unsuccessfully treated digits in the splinted group, 15 were later cured with injections and 2 required surgery. All of the 7 unsuccessfully treated digits in the injected group were cured with surgery. Patients with marked triggering, symptoms of more than 6 months' duration, and multiple involved digits had a higher rate of failure in both groups. Splinting offers an alternative for patients who have a strong objection to cortisone injection.  相似文献   
73.
Endothelin-1 (ET-1) levels are elevated in human breast tumours compared with normal and benign tissues, and in the presence of insulin-like growth factor 1 (IGF-I) ET-1 is a potent mitogen for human breast fibroblasts. In this study we have examined the ability of intact human breast cancer cell lines to process exogenously added big ET-1 (1-38) to the active mature ET-1 peptide by using a specific radioimmunometric assay. In both hormome-dependent (MCF-7, T47-D) and hormone-independent (MDA-MB-231) breast cancer cell lines the putative endothelin-converting enzyme (ECE) exhibited apparent Michaelis-Menten kinetics when converting added big ET-1 to ET-1. Both basal ET-1 production and exogenously added big ET-1 to ET-1 conversion were greatly reduced in all three cell lines in response to the metalloproteinase inhibitor phosphoramidon but were insensitive to other classes of protease inhibitors. Inhibition was also observed when cells were incubated in the presence of the divalent cation chelators 1,10-phenanthroline and EDTA. In MCF-7 cells the optimal pH for the ECE activity using a saponin cell permeabilisation procedure was found to residue within a narrow range of 6.2-7.26. Our results indicate that human breast cancer cells contain a neutral phosphoramidon-sensitive metalloproteinase which can process big ET-1 to ET-1. In the breast this conversion could contribute substantially to the local extracellular levels of this proposed paracrine breast fibroblast mitogen.  相似文献   
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Radiolabeled cocaine analogs can bind to low and high affinity sites on striatal dopamine transporters (DAT). Recently, a cDNA encoding a rat brain dopamine transporter pDAT1 has been cloned. COS cells transfected with the pDAT1 in a eukaryotic expression vector express both a high (KD = 3.4 nM) and low affinity (KD = 163.6 nM) cocaine binding sites, suggesting that both sites are provided by a single gene product.  相似文献   
76.
In a double-blind study a non-invasive method of examining the stability of the precorneal tear film was used to record tear thinning time on a population of 34 independently diagnosed dry eye patients. The results were compared with those for tear output, as inferred from the standard Schirmer tear test, and a correlation coefficient of 0.20 determined. The mean tear thinning time and Schirmer results for the population sample were 6.87 +/- 2.97 sec, and 5.62 +/- 5.69 mm wetting in 5 min, respectively. From a plot of tear thinning time against Schirmer a simple classification for dry eyes can be made. A Type A with normal tear stability and low output accounting for 14.70% of the dry eyes. A Type B with low tear stability and normal output, also accounting for 14.70% of the dry eyes. A Type C with low stability (less than 9.84 sec), and low output (less than 11.31 mm wetting in 5 min) accounting for 70.60% of the dry eyes.  相似文献   
77.
The dose-duration effect of nebulized nedocromil sodium was studied in ten patients with exercise-induced asthma (7 males mean (SEM) age 30.1 (3.5) yrs and predicted forced expiratory volume in one second (FEV1) 102%). All of these patients showed > 40% protection of their exercise asthma with 4 mg of nedocromil sodium delivered via metered dose inhaler. Three concentrations of nedocromil sodium (0.5, 2.5 and 10 mg.ml-1) and placebo were administered in double-blind, randomized manner. One ml of each solution was nebulized via a Wright nebulizer. Effects were assessed from the mean maximal percentage fall in FEV1 after 6-8 min treadmill exercise at 15, 135 and 255 min following each treatment and expressed as percentage protection. The mean baseline FEV1 values before and after treatments were comparable on four days of testing. Nedocromil sodium inhibited exercise-induced fall in FEV1 at all concentrations (p < 0.001) and the inhibitory effect was still present at 255 min. No differences were observed between active treatments.  相似文献   
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Although functional and clinical outcomes after total ankle arthroplasty have been promising, a steep learning curve has been recognized. In addition, the performance of concomitant hindfoot realignment procedures is controversial. The purpose of this study was to report on a single surgeon's experience with the first 50 total ankle arthroplasty procedures. We wanted to define the characteristics of the learning curve and whether the rate of complications was increased in patients who required complex reconstruction for preexistent foot and ankle deformities. This was a retrospective study of 50 cases with an average follow-up of 24.2 months. The patient population consisted of 18 men and 30 women with an average age of 57.6 years. Twenty-six percent of the cases had concomitant bony realignment procedures, while 20% had prior history of major hindfoot corrective procedures. There were 19 cases with intraoperative malleolar fractures, 12 cases that exhibited some degree of malalignment, and 6 cases of syndesmotic nonunion, and 8 ankles required early component revision. Minor wound complications that resolved with local wound care occurred in 9 cases, while 1 patient had a major wound complication requiring flap coverage. Each of these complications, other than wound complications, decreased with the surgeon's experience. Our results also indicate that the performance of major realignment procedures at the same time of implant arthroplasty is not associated with an increased incidence of complications. The results of this study suggest that total ankle arthroplasty is associated with a learning curve. Perioperative complications may potentially decrease with surgeon experience.  相似文献   
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