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991.
In 1986 and 1987, four patients with tibial malunion involving both angular and torsional misalignment underwent surgical correction by a single-cut technique based on a mathematical model of long bone deformity. The technique involved a single surgical cut, followed by rotation of the two fragments along the osteotomy plane. The orientation of the osteotomy is based on a computer-assisted design. The deformity is measured on radiographs, computed tomography, and clinical exam and is then plotted on graphs to find the osteotomy orientation. The deformity involved varus and extension in four cases, internal rotation in 2, and external rotation in two. The deformities ranged from 9 to 26 degrees. The cutting angle of the osteotomy ranged from 50 to 66 degrees as measured from the transverse plane. Actual lengthening of 1 cm and functional lengthening over 1.5 cm was obtained without the use of bone graft. As no wedge of bone was removed, all corrected bones were easily suited to rigid internal fixation across the cut surface. In all cases, the desired correction was obtained within measurable error, and union was obtained with minimal immobilization. There were no soft tissue or joint contractures, and no neurovascular complications. In one patient, who had had four prior surgical procedures on the involved limb, an infection developed 6 weeks postoperatively that required debridement and delayed primary closure. As the technique involves only one cut, no wedge of bone is removed, no shortening occurs, and the osteotomy is highly suitable for rigid internal fixation. The described technique is the first to integrate in a precise way the correction of torsion with the correction of angular deformity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
During a 3-year period Branhamella catarrhalis was isolated in significant numbers from 239 (1.3%) of 19,488 specimens of sputum sent for routine microbiological examination at a 700-bed general hospital. The majority of patients (83%) were over 60 years of age and 65% were male. There was a distinct seasonal variation in isolations with a peak incidence during the winter and early spring, a pattern not found with other pathogens. Susceptibility to amoxycillin decreased by approximately 50% over the 3 years, corresponding to an increased incidence of beta-lactamase-producing strains. There were minimal changes in susceptibility to other antimicrobial agents. Underlying pulmonary disease was the major factor predisposing to B. catarrhalis infection, and 71% of patients were smokers or ex-smokers.  相似文献   
993.
The syndrome of Maffucci is characterized by angioma association of the enchondromatose. It is a relatively rare syndrome. The lesions are evolutived. The treatment is surgical. His pronostic is marqued by high percentage of malign degenerescence.  相似文献   
994.
995.
Since 1962, lasers have been used in dermatology and have become the first choice in the treatment of superficial, vascular ectasia. Lasers are unique sources of light; they are coherent, monochromatic, collimated and intense. By careful selection of wavelength, pulse duration, and intensity, it is often possible to selectively confine a laser effect to a specific histologic structure in tissue, depending upon the tissue properties. The ideal treatment of Port Wine Stains (PWS) should irreversibly damage the ectatic vessels but minimize heating of the epidermis and superficial dermis. A theory, called selective photothermolysis, predicts the optimal combination of laser parameters of achieving this ideal treatment of PWS to be a wavelength of 577 nm, a pulse duration of 0.35-10 msec, and an energy per surface area of about 7-8 J/cm2. Laser wavelength: The wavelength of 577 nm is preferred because it: maximizes the selective absorption by hemoglobin, minimizes absorption by epidermal melanin, provides sufficient depth of penetration in the blood to coagulate 0.1 mm vessels allows penetration of light into dermis up to 1 mm. Laser pulse duration: A pulse-width in the range of 0.35-10 msec allows the temperature elevation to be uniform inside the vessel and to be confined to the vessel area. Shorter pulses superheat the red blood cells causing explosive boiling and hemorrhage. Longer pulses allow heat to diffuse away from vessels, requiring greater energies per pulse to achieve vessel damage. An increased energy per pulse increases the risk of excessive damage to surrounding tissue.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
997.
998.
999.
The bioavailability of a new sustained-release potassium chloride (KC1) tablet, designed for once-a-day dosing, was compared to a KC1 elixir using urinary excretion data. The study utilized 25 male volunteers dosed in a crossover design in a dietary/activity-controlled environment. The regimens consisted of a total of 80 mEq of potassium in three equally divided doses of elixir every 6 hr and a single 80-mEq dose using four 20-mEq sustained-release (SR) tablets. The mean time to maximum rate of potassium urinary excretion was 2.2 hr for the first elixir dose and 5.5 hr after the SR tablet (P < 0.01), thereby supporting the prolonged-release properties of this formulation. After correction for baseline urinary potassium excretion, the mean total 24-hr urinary potassium excretion was 42.18 mEq for the elixir and 40.41 mEq for the SR tablet. The results indicate that the absorption pattern from the SR tablet is equal to three doses of KC1 elixir dosed 6 hr apart.  相似文献   
1000.
Fifty-four patients with 65 superficial malignant lesions were treated by local hyperthermia combined with radiation therapy at the National Cancer Center Hospital, Tokyo. Hyperthermia was delivered with an Aloka Model HMS-020 (2450 MHz) or with a horn-type applicator of BSD-1000 (80-90 MHz). Relatively small tumours, those less than 4 cm in thickness, were treated by using 2450 MHz while 80-90 MHz delivered through the horn-type applicator was used for tumours exceeding 5 cm in thickness. The radiation dose was 4 Gy twice a week or 2 Gy five times a week, the total dose being 40-60 Gy. A total of six to 10 hyperthermia treatments ranging from 40 to 60 min each, with the tumour heated to more than 42.5 degrees C, were given twice a week within 1 h following radiation therapy. Complete response was achieved in 16 of the 30 patients (55 per cent) treated with the 2450 MHz microwave, and partial response in seven others (23 per cent). Tumours treated with the BSD-1000 achieved complete response in 10 out of 33 patients (30 per cent) and partial response in nine others (27 per cent). In five out of nine patients classified as partial responders, however, complete disappearance of tumour cells was noted by post-treatment histological examination. Complete plus partial response rates were thus essentially the same with the Aloka HMS-020 and the BSD-1000, though the rate of complete response was apparently higher with the Aloka unit, probably because it was used on smaller tumours.  相似文献   
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