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101.
OBJECTIVE: To determine the progression of thoracolumbar disc degeneration in young fast bowlers in cricket. DESIGN: Prospective fast bowling technique and MRI follow-up study. BACKGROUND: Previous studies on high-performance young fast bowlers have found that lumbar spine pathology was related to the mixed bowling technique. METHODS: Nineteen young male fast bowlers (mean age 13.6 years) underwent MRI scans to detect the presence of intervertebral disc abnormalities. Subjects were also filmed laterally (200 Hz) and from directly above (100 Hz) whilst bowling two maximum velocity deliveries (session 1). Subjects were tested using an identical methodology 2.7 years later (session 2). RESULTS: At session 1, the incidence of thoracolumbar disc degeneration was 21%; however, at session 2, the incidence significantly (P = 0.008) increased to 58%. Furthermore the increase in the incidence of back pain between session 1 and session 2 was also significant (P = 0.002). The progression of disc degeneration was found to be significantly (P = 0.015) related to the group of fast bowlers who utilized the mixed technique during both session 1 and 2 when compared to those who used this technique during one session only. CONCLUSIONS: Thoracolumbar disc degeneration and back pain increase significantly during the time period examined in this study. Further, bowlers who utilize the mixed bowling technique stand a greater chance of developing degenerative changes of the spine.  相似文献   
102.
CI-921, the 5-methyl-4-carboxamide analog of amsacrine, in combination with cisplatin produced a 6-fold better cell kill in vitro than expected based on additive effects. The combination of CI-921 and cisplatin was subsequently evaluated in three in vivo model systems: intraperitoneally (TP) and intravenously (IV) implanted P388 leukemia, and advanced stage subcutaneously (SC) implanted LC-12 squamous cell carcinoma. All drug treatments were administered IP on an intermittent treatment schedule which was optimal for both agents. Combination therapy was superior to therapy with the best single agent alone, CI-921, in all three model systems. Against IP implanted P388 leukemia, combination therapy produced greater than 8 logs of net tumor cell kill with 60-day survivors (cures). This level of activity was 50-fold greater (1.7 log) than that obtained with CI-921 alone. An IV implant of P388 leukemia was used in a confirmatory study to provide a more rigorous evaluation against disseminated disease. Combination therapy against IV implanted P388 leukemia produced greater than 7.7 logs of net tumor cell kill, which was 630-fold greater (2.8 logs) than that obtained with CI-921 therapy alone. Against advanced stage LC-12 (200-1000 mg tumors at initial treatment), combination therapy improved tumor cell kill by 0.6 log (4-fold) over that obtained with CI-921 therapy alone and also produced greater numbers of 120-day survivors than did single agent therapy with CI-921. The combination of carboplatin and CI-921 was also evaluated against IV implanted P388 leukemia to determine if the enhanced therapeutic effect of CI-921 and cisplatin could be extended to include CI-921 and carboplatin. Combination therapy with CI-921 and carboplatin increased net log tumor cell kill by 0.8 and 1.5 log in two separate tests (6- and 32-fold, respectively) over that obtained with CI-921 therapy alone. The data indicate that combination therapy with CI-921 and platinum containing anticancer agents may have clinical application.  相似文献   
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The authors percutaneously placed 45 catheters for peritoneal dialysis in 32 patients, aged 31-83 years, in a radiology department. In all patients, the procedure was modified by use of the Hawkins needle, and in response to the high frequency of extrusion of the proximal cuff, the deep cuff of the 16th and each subsequent catheter was sutured to the rectus muscle or fascia. After 17 catheters were placed, the catheter was modified with a permanent bend, or "U" neck, between the two cuffs, which were then thickened. All procedures were performed with use of local anesthesia, and all catheters were successfully placed. Acute complications included bowel perforation associated with peritonitis in one patient (2%). Delayed complications included cuff extrusion in nine patients (20%), obstruction in nine patients (20%), and peritonitis requiring removal of the catheter in three patients (7%). This study shows the feasibility of percutaneous placement of peritoneal dialysis catheters by radiologists despite the need for improved technique and equipment.  相似文献   
108.
Seabird tissues, collected during the 1988 breeding season from colonies on the Atlantic coast of Canada, were analyzed for toxic metals—Cd, Hg and Pb—and 18 other trace elements. Metallothionein (MT) was measured in kidney, and kidneys and livers underwent histopathological examination. Levels of most essential trace elements appear to be closely regulated in seabird tissues; values were in good agreement with those previously reported in the published literature. Liver-Se concentrations in Leach's storm-petrels (Oceanodroma leucorhoa) (77.6+7.49 g/g dry weight) were much higher than values normally reported for freeliving birds and mammals. Cd levels varied greatly among individuals, but were always higher in kidney than in liver. Highest mean Cd concentrations (183+65 g/g dry weight) were in kidneys of the planktivorous Leach's storm-petrels from the Gulf of St. Lawrence. A few individuals of this species had values >300 g/g dry weight. Cd and metallothionein (MT) concentrations were positively correlated in kidneys of Leach's storm-petrels (r=0.692), Atlantic puffin (Fratercula arctica) (r=0.845) and herring gull (Larus argentatus) (r=0.866). Concentrations of total Hg varied greatly among species and individuals, but were consistently higher in liver than in kidney. Highest mean levels (21+28 g/g) were in livers of the piscivorous double-crested cormorant (Phalacrocorax auritus) from Saint John Harbour in the Bay of Fundy. Concentrations of Hg and Se were positively correlated (r=0.736) in livers of Leach's storm-petrel, but not in other species. Pb concentrations were consistently greatest in bone, with mean levels being highest in herring gulls from a colony in the Bay of Fundy (63+36 g/g). Histological examination of liver and kidney failed to reveal indications of tissue damage associated with elevated levels of heavy metals.  相似文献   
109.
Breast reconstruction today is a realistic and vital part of total breast cancer treatment. All physicians should be well informed on current methods of reconstruction so that they can present the facts to their patients in an encouraging, yet realistic manner. Recent developments in breast reconstruction after mastectomy have included the increase utilization of immediate breast reconstruction at the time of mastectomy, the improvement and refinement of the TRAM flap, the increased use of the "free" flap transfer of the TRAM flap which increases blood supply to the flap, texturing of implants which appears to increase their stability on the chest wall and reduce the incidence of capsular contracture or firmness, and the introduction of the newer autogenous tissue methods including the LTTF, gluteal, and latissimus dorsi flaps. Plastic surgeons are charged with the task of becoming proficient in breast reconstruction procedures in order to offer the mastectomy patient a safe, realistic facsimile breast that will be trouble free. Fortunately, there are several good options for restoring the breast after mastectomy. The method of reconstruction should be chosen by matching the desires of informed patients with the indications and contraindications in each case. In general, silicone reconstruction is expedient and satisfactory in most patients. However, it cannot compete with autogenous tissue transfer for severe chest wall defects, covering irradiated areas, creating a large, ptotic breast, or providing a natural appearing, soft breast mount.  相似文献   
110.
Hypertension may result from chronic lead exposure. Lead poisoning arising from "moonshine whiskey" drinking has been associated with a rise in plasma renin activity. In the present study, plasma renin concentration following intravenous administration of frusemide was measured in eleven subjects with moderate or severe lead poisoning of industrial origin. The results were compared with those obtained for seven normal, control subjects. There was no significant difference in response obtained in the two groups. Industrial lead poisoning does not appear to affect renin release. The combined insult of lead and alcohol may explain the findings in the previous study.  相似文献   
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