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21.
A distinctive systematized epithelial nevus and associated multifocal carcinomas of the microcystic and sclerosing sweat duct type affected the lower extremities of a 9-year-old girl. The carcinomas were well differentiated and were both adenosyringomatous and microcystic. They qualify as microcystic and compound. In both the epithelial nevi and the carcinoma, primordial potentials are recapitulated.  相似文献   
22.
Solid customized and prefabricated silicone implants have been used by the author for 15 years in a wide range of chest wall deformities. Chest wall implants are often used in males seeking to augment a muscularly deficient or underdeveloped chest; however, their greatest use has come in a variety of deformities both congenital and acquired, such as pectus excavatum, Poland's Syndrome, and pectoralis muscle tears. The implants can be either customized using a moulage technique or are prefabricated, manufactured implants which can be modified on the operating table to repair the contour deformity. The immediate postoperative problem of seroma and subcutaneous implant ``show' has been minimized by careful planning, gentle technique, deep insertion, improved patient positioning on the operating room table, and the use of oral anti-inflammatory medications. The long-term results of these implants seem very satisfactory. The patients are usualy physically active, and the implants show no long-term sequelae such as seroma, infection, displacement, or rupture.  相似文献   
23.
Purpose To compare the differences in practice and outcome of all radiologically and surgically placed central venous catheters retrospectively over a 2-year period simultaneously, at a single institution. Methods A total of 253 Hickman catheters were inserted in 209 patients; 120 were placed radiologically in 102 patients and 133 were placed surgically in 107 patients. The indication was chemotherapy in 76% of radiological and in 47% of surgical cases; the remainder were for total parenteral nutrition and venous access. Results There were 6 (4.5%) primary surgical failures and a further 17 (13%) surgical cases requiring multiple placement attempts. Pneumothorax occurred once (0.8%) surgically and four times (3.3%) radiologically. There were no radiological primary misplacements but there were five (3.7%) surgical ones. Catheter or central vein thrombosis occurred in four (3.3%) radiological and five (3.7%) surgical cases. The rate of infection per 1000 catheter-days was 1.9 in radiologically placed catheters and 4.0 in surgically placed ones (p<0.001). Average catheter life-span was similar for the two placement methods (100±23 days). Conclusion Radiological placement is consistently more reliable than surgical placement. There are fewer placement complications and fewer catheter infections overall.  相似文献   
24.
During transesophageal echocardiography probe passage, airway reflexes are usually obtunded with topical local anesthetics. This technique meets with varying degrees of success. Even partially intact airway reflexes result in coughing, retching, and withdrawal, which may prevent transesophageal echocardiography examination or predispose to life-threatening tachycardia and hypertension. Proper preparation of the patient enhances comfort and helps protect against tachycardia and hypertension as well as reducing the time required for examination. This article outlines specific monitoring issues and offers precautions that are critical to transesophageal echocardiography probe passage. It suggests a premedication regimen and describes methods of sedation. Furthermore, it outlines the afferent innervation of the upper airway and specific techniques of temporary reflex interruption.  相似文献   
25.
T C Keys  M A Judson  C E Reed    S A Sahn 《Thorax》1994,49(5):525-526
A 27 year old HIV infected man presented with two days of haemoptysis. Flexible bronchoscopy revealed a large carinal mass partially obstructing the left and right main stem bronchi. Rigid bronchoscopy was required to make the diagnosis of large cell immunoblastic lymphoma.  相似文献   
26.
Pharmacy and therapeutics committees commonly cite a lack of generalizability as a reason for not incorporating cost-effectiveness information into decision making. To address this concern, many committees undertake site-specific economic evaluations, which are often limited by small sample sizes and nonrandomized designs. We show how 2 complementary approaches were used to minimize these limitations in an economic evaluation of abciximab at 1 institution. Using a propensity score methodology, we selected patients who did not receive abciximab for the comparison cohort. Then, we adopted a Bayesian, hierarchical, random-effects model to integrate site-specific and clinical trial data. We applied the posterior distributions of effectiveness with local cost data in a traditional decision-analytic model. In 74% of the simulations, abciximab was cost-effective at 1 institution at the $50,000 per life year saved threshold, assuming a 50:50 split of patients undergoing coronary stenting and angioplasty. Among patients undergoing coronary stenting, the cost-effectiveness ratio of the addition of abciximab was at or below the $50,000 per life year saved threshold in 66.0% of the simulations.  相似文献   
27.
We examined the relationship of history of alcoholism in first-degree relatives to neuropsychological performance of alcoholics abstinent from several weeks to several years. Eighty-four men were assigned to four groups based on "strength" of family history of alcoholism. The groups were: (1) "strong history," a parent plus another first-degree relative positive; (2) "moderate," parent only positive; (3) "weak," nonparent first-degree relative only positive; and (4) "negative," no first-degree relative positive. There were no significant between-group differences in NP performance. In other analyses there were no NP differences between alcoholics classified positive or negative purely on basis of paternal alcoholism, and no differences between subjects who had multigenerational versus unigenerational versus negative familial histories of alcoholism. It is concluded that genetic loading for alcoholism does not significantly affect the NP status of abstinent alcoholic groups equated for education, drinking history, and medical risk.  相似文献   
28.
Examined the effects of two instructional methods on language generalization and longterm retention in 23 adults with autism and severe to profound mental retardation. Analog language teaching employed discrete trials in a controlled setting concentrating on discrimination and identification of materials. Natural language teaching emphasized instruction through interactions that occurred incidentally to training students in the use of materials to perform functional tasks. Assessments were conducted under conditions favoring analog teaching to assure against partiality toward natural language teaching. Under such disadvantageous conditions, the methods of natural language teaching would be supported by results showing either no difference or an advantage in their favor. Both techniques increased initial and long-term generalization though the results suggest no relative superiority for either method under these assessment conditions. A significant interaction was found between prior functioning level and sequence of instruction. Because natural language teaching has many strengths, few drawbacks, and produces equal generalization and retention under disadvantageous conditions, it is strongly supported as preferable for people with autism and mental retardation.The authors acknowledge the important assistance provided by the following people: the staff and management of the Behavior Development and Learning Center at CSH/DC directed by Israel Perel, Lisa Kramer, Steve Hafferkamp, James Lowdermilk, and, finally, and especially, to the participants themselves.  相似文献   
29.
OBJECTIVE: We studied the relationship between endurance training, aerobic capacity, and T3 metabolism in healthy euthyroid men. DESIGN: T3 kinetic studies performed on two groups of subjects differentiated on the basis of physical activity status and aerobic capacity. SUBJECTS: Five endurance-trained athletes and five sedentary controls (mean +/- SD VO2 max = 48.2 +/- 7.1 vs 23.2 +/- 4.5 ml/kg/min, respectively) matched for age, body surface area, lean body mass, and baseline thyroid function. MEASUREMENTS: Kinetic analysis performed using serial serum T3 levels measured following oral T3 administration. Metabolic clearance rate, total volume of distribution, disposal rate, and total body pool calculated using non-compartmental analysis. RESULTS: When normalized for lean body mass, all kinetic parameters were 25-38% greater in the athletic group compared to controls (P < 0.05). Total volume of distribution, disposal rate, and total body pool were positively correlated with aerobic capacity (r = +0.69 to +0.79; P < 0.05). Metabolic clearance rate was positively correlated to a non-significant degree. CONCLUSIONS: These results confirm the findings of prior studies that thyroid hormone metabolism is altered by physical conditioning. In addition, we demonstrated a positive correlation between aerobic capacity and several parameters of T3 kinetics. Differences in absolute lean body mass cannot explain these findings; rather it appears that there is something qualitatively different in the way endurance-trained tissue processes thyroid hormone, compared to untrained tissue. The study was not designed to elucidate these differences at the cellular level; however, it does support a link between muscle physiology and T3 activity and may suggest a physiological role for thyroid hormone in physical conditioning.  相似文献   
30.
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