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21.
Summary 2-deoxycoformycin (2-dCF; Pentostatin), a stoichiometric inhibitor of mammalian adenosine deaminase (ado deaminase), exhibits immunosuppressive and antilymphocytic activity in animal test systems. A clinical pharmacology/phase I study of 2-dCF administered as a single agent has been completed (18 patients). Dose levels ranged from 0.1 mg/kgx1 to 0.25 mg/kg/dayx5; ado deaminase and 2-dCF were measured spectrophotometrically. Plasma decay curves were bi-exponential ( and t1/2 values about 1 and 10 h respectively). Recovery of unchanged 2-dCF from urine (48 h) was 32%–48% of the administered drug. Major toxic manifestations were lymphocytopenia (all patients) and urate nephropathy (1 patient, with subsequent patients in the series receiving allopurinol, 300 mg/day). Three partial responses were seen in seven patients with acute lymphocytic leukaemia receiving 0.25 mg 2-dCF/kg/dayx5.  相似文献   
22.
Summary The execution of clinical trials is perhaps the most difficult way of carrying out a scientific experiment. This is especially true of chronic diseases, such as breast cancer, which require long-term follow-up and large numbers of patients. As a result, it is necessary to involve many physicians who can contribute patients to these studies. Unfortunately, many physicians are not comfortable participating in randomized studies because they feel the patient—physician relationship may be compromised. This paper discusses new ways of planning randomized clinical trials which do not interfere with the patient—physician relationship. The new designs are called randomized consent or prerandomized designs. The study designs are discussed from the point of view of statistical efficiency and the new ethical problems which may arise. Address for reprints: Marvin Zelen, Ph.D., Department of Biostatistics, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA  相似文献   
23.
Jacques Lisfranc was born in Saint-Paul-Jarrest (Loire), France, April 2nd, 1790, the son of a physician. Early in his youth he demonstrated a particular interest and aptitude for the field of medicine as he observed and commented upon his father's ministrations to his patients. He accomplished his preliminary studies at the Lyceum in Lyons and then went to Paris to continue his medical training at the Hôtel-Dieu. It was there that he came under the tutelage of Dupuytren. It was soon said that Lisfranc was at least as worthy as his superior. Later the two men developed a certain animosity toward each other which became manifest rather severely in the medical political arenas of the time. Lisfranc received his doctorate of medicine in 1812 at a time that France was involved in the Napoleonic wars. He was commissioned as a surgeon and distinguished himself in campaigns in Saxony and in France. Following the war he established his practice in Paris. Fortuitously, one day Lisfranc rescued a magistrate who fell from his horse. By this serendipitous meeting Lisfranc was invited to join the faculty of medicine at the Hospital of Pity. He rose rapidly to chief of surgery and developed the reputation of being extremely competent, truly a master surgeon. For over 20 years he was affiliated with that institution and wrote numerous articles on such diverse subjects as shoulder disarticulation, the application of the stethoscope in the diagnosis of fractures, and on diseases of the uterus. In addition, he wrote two books which were well received—one onSurgery at the Hospital of Pity and the other onOperative Medicine. ThisClassics presentation has been selected because it has been generally attributed that Lisfranc was the first person to remove a cancerous tumor from the rectum. The technique involves essentially a transanal approach. As was the custom of the day, the report appears as narrated presumably by one of his assistants. Among the many distinctions Lisfranc achieved, he was founding member and ultimately President of the French Academy of Medicine and Chevalier of the Legion of Honor. Lisfranc developed an enormous clinical practice, and in spite of many physical infirmities he persisted in his surgery until the day of his death, May 12, 1847, at the age of 57.  相似文献   
24.
Knowledge of the location of the hypoglossal/lingual artery neurovascular bundle (HLNVB) is essential in performing tongue base resections for neoplasm and for obstructive sleep apnea. Transoral and transcervical resections of the tongue base may be performed with greater exposure and certainty when the relationship of the HLNVB to local landmarks is understood; knowledge of the HLNVB allows resection of a larger amount of contralateral tongue base during partial glossectomy without violating the contralateral remnant tongue's blood supply. Ten cadaver heads were dissected to determine the position of the HLNVB with respect to soft tissue and bony landmarks at the tongue base. Our results indicate the position of the tongue base HLNVB is significantly inferior and lateral, that is, 2.7 cm inferior and 1.6 cm lateral to the foramen cecum, 0.9 cm superior to the hyoid bone, and 2.2 cm medial to the mandible. This inferolateral location allows the potential for aggressive tongue base resection without neurovascular compromise.  相似文献   
25.
Objectives: A prospective study comparing the efficiacy and side-effects of oral sulindac with intravenous indomethacin in clinically stable preterm infants (<1750 g) requiring non-invasive closure of haemodynamically significant patent ductus arteriosus.
Methodology: As maturity and birthweight are the two major determinants of ductal closure, infants were matched as closely as possible for these parameters. An eligible patient was first assigned to the sulindac group and a subsequent patient with similar gestational age (± 1 week) and birthweight (±100 g) to the previously recruited infant would automatically receive indomethacin. A total of eight infants were enrolled in each group.
Results: The ductus arteriosus was successfully closed in all eight infants receiving indomethacin, and in seven of eight infants receiving sulindac. No significant differences were found with regards to the ductal size between the two groups at diagnosis or on each of the consecutive days of treatment ( P >0.25). More renal adverse effects were encountered in the indomethacin group. Significant differences in changes from baseline value for urine output, plasma sodium, urea and creatinine concentrations were noted at 24, 48 and 72 h after commencement of treatment between the two groups ( P <0.05). All the parameters returned to normal or pre-treatment levels 48 h after stopping therapy. Unexpectedly, severe gastrointestinal complications were encountered in the sulindac group.
Conclusions: Sulindac is capable of promoting ductal constriction in clinically stable preterm infants without compromising the renal function. The spectrum of gastrointestinal complications observed in sulindac treated infants were similar to those described for indomethacin. The use of sulindac for ductal closure in the preterm infant should remain experimental.  相似文献   
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Long-term gastrointestinal (GI) and urinary tract (UT) complications were evaluated in 48 women treated by radical hysterectomy (RH) and pelvic node dissection (PND) and in 25 women who received 5000–5400 rad of external pelvic radiation (RT) after RH-PND. No major complications developed in the surgery-only group, but the 5-year minor GI complication rate was 4% and the 5-year minor UT complication rate was 10%. In 9 patients receiving RT at 200 rad/day, one major GI complication (13%) and one major UT complication (14%) developed. In 16 patients receiving RT at 180 rad/day only minor GI complications (7%) and minor UT complications (13%) developed. The conclusion is that after RH-PND, adjunctive RT delivered at 180 rad/day through four ports results in acceptable, minimal complications.  相似文献   
29.
Vehicle effects on the percutaneous absorption of nicardipine base, nicardipine hydrochloride, ketorolac acid, and ketorolac tromethamine were determined using the rhesus monkey as an in vivo model for human skin penetration. Vehicles investigated included blends of propylene glycol, trimethylene glycol, ethanol, Azone, Tween 20, water, and long-chain fatty acids. Formulations were prepared such that the compound dose, application area, and percentage saturation of the compound in the vehicle were held constant. Variations in absorption of the compounds were therefore attributable to vehicle effects. Each formulation was applied to three monkeys for a period of 24 hr using 10 Hill Top Chambers. Plasma samples were taken at appropriate intervals for 36 to 48 hr. The results indicated that trimethylene glycol and Tween 20 did not enhance absorption of the test compounds despite claims by other investigators. Azone and ethanol provided moderate enhancement of both the rate and the extent of absorption, while long-chain fatty acids in combination with propylene glycol significantly enhanced penetration. In general, higher fluxes were observed with the more lipophilic compounds nicardipine base and ketorolac acid as compared to the hydrochloride and tromethamine salts.  相似文献   
30.
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