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21.
Significant patellofemoral chondromalacia was observed three months after operations on goat knees that had an excised anterior cruciate ligament (ACL) replaced and then were immobilized for six weeks with a rigid external pin and frame fixator. To determine if the patellofemoral morbidity rate could be reduced, another group of goats was treated with the same operation but without immobilization. The legs of the animals in the immobilized group had muscle weakness and the animals only occasionally used their legs for the next three to four weeks. The animals in the mobilized group protected the leg for only one to two days after surgery, and by ten to 12 days were actively moving the knee. Severe patellofemoral articular cartilage erosions occurred in the immobilized goats but not in the mobilized group. Postoperative immobilization was detrimental to the joint function and to a successful ACL reconstruction.  相似文献   
22.
Ninety-three women with FIGO stage II epithelial ovarian carcinoma underwent comprehensive surgical staging and were randomized prospectively to therapy consisting of either intraperitoneal radioactive phosphorus or oral melphalan. No patient had gross residual disease at the time of randomization. Ten of the forty-five women treated with melphalan experienced severe bone marrow depression at some time during therapy and two women expired from leukemia. Four of the forty-eight women treated with intraperitoneal phosphorus required surgical reexploration for intestinal obstruction or bowel injury. Twenty-one women died of their disease. Survival was not statistically different between the two treatment arms. The 5-year actuarial survival was 78%.  相似文献   
23.
The cholesterol-fed rat model has been used to examine the distribution of radiolabeled cholesterol by whole-body autoradiographic and quantitative videodensitometric methods. Animals were fed a hypercholesterolemic diet for 7 days, and were subsequently killed at 3, 6, 12, 24, or 72 h following a single oral dose of [14C]cholesterol. Maximum blood and tissue levels were observed at 12 h, while liver and adrenals were the most intensely labeled tissues. Liver maintained consistently high levels over the course of the study, while activity in other tissues declined moderately by 72 h, indicating the long half-life of cholesterol radioequivalents in tissue. The results of these experiments suggest that autoradiographic examination of cholesterol distribution in animals treated with pharmaceutical agents designed to modify cholesterol absorption or clearance will be useful in providing supplemental or confirmatory information on the drugs' mode of action.  相似文献   
24.
353 patients with stages pTis, pT1-2, pN0-1, cM0 breast cancer have been treated consecutively by breast conserving therapy in a prospective, nonrandomized study at the University Hospital Basel and the Women's Clinic Rheinfelden/Baden/Germany. The median age was 47 years, the median follow-up time 67 months, and 4% only of this collective were lost to follow-up after a median time of 42 months. In 79% of the cases the tumor was excised totally, while in 19% the resection margins were positive and in 2% only the margins were not available for histological judgement. The rate of local failure reached 8% with a median time interval of 53 months. 116 patients showed postactinic induration in the primary tumor region. 73 of these were given additional diagnostic examination: The postactinic induration was judget clinically suspicious in 51 cases and clinically nonsuspicious of local failure in 22 cases. All 73 patients received additional examination by mammography and biopsy. By comparison with the histological results the clinical results were correct in 59% and false in 41%, while the mammographic results were correct in 82% and false in 18% of the cases.  相似文献   
25.
Epigard (Synthes, Paoli, PA), a synthetic skin substitute, is useful in the temporary covering of surgical wounds. The dressing adheres to the wound bed, provides hemostasis, and aids neovascularization. When removed after 2-3 days, the surgeon has a wound ready to accept a graft.  相似文献   
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27.
Electric stimuli with durations of 0.5-1.0 msec are optimal for studies of H-reflexes. It is more difficult to obtain H-reflexes with shorter duration stimuli or with magnetic stimulation. In order to understand this behavior, we studied the excitation thresholds for motor and sensory fibers in the ulnar, median and tibial nerves using both electric and magnetic stimulation. For short duration electrical stimuli (0.1 msec) the threshold for motor fibers is lower than for sensory fibers. For longer duration electric stimuli (1.0 msec) the threshold for sensory fibers is lower. For magnetic stimulation the threshold for motor fibers is much lower than for sensory fibers. Thus, stimulus duration is a critical parameter for sensory fiber excitation, and current magnetic stimulators are not optimal.  相似文献   
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29.
We describe a woman whose fatal post-liver transplantation cerebral edema was unexpected and of unusual pathogenesis. Her severe cerebral edema is of considerable pathophysiologic interest: 1) it developed in the setting of marked anasarca and persistent hypernatremia, and 2) although hepatic function was poor, it was not considered sufficiently deranged to induce cerebral edema. Furthermore, there was no histologic evidence of hepatic rejection or antemortem hepatic necrosis. We postulate that an impairment of the blood brain barrier in association with a degree of hepatic dysfunction insufficient by itself to cause cerebral edema permitted the brain interstitial fluid volume to increase pari passu with ECF expansion. Cytotoxic cerebral edema and vascular engorgement may also have contributed to a life-threatening increase in intracranial pressure.  相似文献   
30.
The placental-site trophoblastic tumor is a rare form of gestational trophoblastic neoplasia. Although originally considered benign, it is now apparent that this lesion can be associated with aggressive clinical behavior. Our study examined the DNA ploidy status and clinicopathologic features of four new cases of placental-site trophoblastic tumor. Three cases demonstrated diploid DNA stemlines with S-phase fractions ranging from 6% to 16%. These patients were alive and well at follow-up and had low-serum human chorionic gonadotrophin (hCG) levels. A fourth patient, who had a large tumor, demonstrated a tetraploid DNA peak with a prominent S-phase fraction. This patient exhibited an elevated serum hCG at limited follow-up. Flow cytometric DNA analysis may be a useful adjunct for the identification of placental-site trophoblastic tumors with malignant potential.  相似文献   
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