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Nine volunteer subjects were tested with intravenously administered cocaine hydrochloride in doses ranging from 4 to 32 mg, as well as 10 mg of dextroamphetamine sulfate. Measures of cardiovascular and subjective effects were made. Generally parallel dose-effect functions were obtained for heart rate, blood pressure, Addiction Research Center Inventory scores, Profile of Mood Scales, and subject ratings. A substantial effect on each of these variables was recorded after 8 mg of cocaine. The increase continued and peaked at approximately 16 mg after which it usually leveled off. Ten milligrams of dextroamphetamine generally had an effect comparable to 8 to 16 mg of cocaine.  相似文献   
3.
The persistence of metatarsus adductus varus has been a problem in management. We have treated a series of selected patients with this problem and believe that our results have been better than with the procedure we have used in the past. Fowler has described a procedure which seems ideal for the patients in our series. Through personal communication the procedure and its application were discussed and the series was started eight years ago. Our series is small because our patients are responding to other forms of treatment at an earlier age. The few that do not respond are now considered for the operation described. The procedure is relatively simple to perform. Full correction should be obtained at the time of surgery. Casting is utilized to hold the correction and immobilize the extremity for healing. Our unsatisfactory results occurred because of errors in technique or poor selection of patients. We believe that this procedure should be considered in the older patient with metatarsus varus.  相似文献   
4.
Spinach chloroplasts, isolated by techniques yielding preparations with high O2- evolving activity, showed rates of light-dependent acetate incorporation into lipids 3-4 fold higher than any previously reported. Incorporation rates as high as 500 nmol of acetate/h per mg of chlorophyll were measured in buffered sorbitol solutions containing only NaHCO3 and [1-14C]acetate, and as high as 800 nmol/h per mg of chlorophyll when 0.13 mM-Triton X-100 was also included in the reaction media. The fatty acids synthesized were predominantly oleic (70-80% of the total fatty acid radioactivity) and palmitic (20-25%) with only minor amounts (1-5%) of linoleic acid. Linolenic acid synthesis was not detected in the system in vitro. Free fatty acids accounted for 70-90% of the radioactivity incorporated and the remainder was shared fairly evenly between 1,2-diacylglycerols and polar lipids. Oleic acid constituted 80-90% of the free fatty acids synthesized, but the diacylglycerols and polar lipids contained slightly more palmitic acid than oleic acid. Triton X-100 stimulated the synthesis of diacylglycerols 3-6 fold, but stimulated free fatty acid synthesis only 1-1.5-fold. Added glycerol 1-phosphate stimulated both the synthesis of diacylglycerols and palmitic acid relative to oleic acid, but did not increase acetate incorporation into total chloroplast lipids. CoA and ATP, when added separately, stimulated acetate incorporation into chloroplast lipids to variable extents and had no effect on the types of lipid synthesized, but when added together resulted in 34% of the incorporated acetate appearing in long-chain acyl-CoA. Pyruvate was a much less effective precursor of chloroplast fatty acids than was acetate.  相似文献   
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The management of dialysis access requires the awareness that any single access site is finite. A commitment to maintain access is reasonable with a planned approach. Dialysis for the end-stage renal disease patient must continue acutely during the management of access complications, and chronically. The goal of treatment is to return the patient to a routine dialysis regimen as soon as possible. Suspected infections should be treated immediately with systemic antibiotics specific for resistant Staphylococcus aureus. Systemic infection should be controlled before a new foreign body is implanted. My personal philosophy of access includes the following principles. (1) distal is good, (2) preserve all possible sites, (3) arm is better than leg, and (4) everything is relative.  相似文献   
7.
Nine cases of sacro-iliac pyarthrosis are presented. The difficulty in localizing the infection is attributable mostly to failure to appreciate the posteriorly situated physical findings. This, and the difficulty with early roentgenographic demonstration of the lesion, may lead to unnecessary abdominal exploration (as in two of our patients) or to prolonged delay in diagnosis and hence spread of the infection. Awareness of the usual physical findings and prompt use of radioisotope scanning to localize the infection led to earlier diagnosis and avoidance of surgery in three patients seen recently. Antibiotic therapy, with or without surgery, led to cure in all patients, with minimum sequelae.  相似文献   
8.
Four hundred seventy blood access procedures performed on 170 dialysis patients during the period 1962-1975 have been analyzed according to survival of access with respect to age, sex and cause of failure. Subcutaneous forms of blood access have a significantly longer life and are more free of complications than external shunts. Although the mode of access can now be tailored to the individual patient, the arterio-venous fistula remains the least expensive and simplest surgical procedure. It should therefore remain as the first choice of access for most patients.  相似文献   
9.
The records of 185 consecutive patients having myocardial revascularization were reviewed with regard to preoperative administration of propranolol and intraoperative or postoperative complications. Tachycardia and hypertension before cardiopulmonary bypass were slightly more common in patients never taking propranolol or those who had discontinued it for more than 48 hours before operation. There was no statistically significant difference in the incidence of postbypass hypotension among patients who took propranolol within 24 hours of operation, those who discontinued it more than 24 hours before operation, and those who never took the drug. Operative mortality was not significantly different among patients who received propranolol within 48 hours of operation (3%), those who never took it and those who discontinued it more than 48 hours before operation (4%). Early in the series, five patients had an acute myocardial infarction within 48 hours after routine preoperative withdrawal of propranolol. Because complete withdrawal of propranolol in patients with unstable angina pectoris may lead to acute myocardial infarction, we recommend gradual withdrawal of the drug during 48 hours before operation. If this is not possible because anginal pain recurs or intensifies, then reduced doses may be given safely up to 10 hours before revascularization, provided that the patient is a satisfactory candidate for bypass and that adequate myocardial revascularization can be accomplished.  相似文献   
10.
Thirty-four of 54 campers on a 2 week trip in mountains of Utah had diarrhea during and after their trip. Twenty-two (79%) of 28 symptomatic campers' stools examined contained Giardia lamblia cysts, whereas 4 (29%) of 14 asymptomatic campers' stools had cysts. The temporal distribution of cases and the absence of clustering among food preparation subgroups suggested a common source exposure. Although the epidemiologic data and fecal coliform counts implicated the remote mountain stream used as water source by the group as the vehicle of transmission, Giardia lamblia cysts were not recovered from stream water nor were they found in intestines or feces of sampled mammals living in the drainage area. Twenty-five other campers had stools examined before and after a subsequent hiking trip in another area of Utah; none had Giardia cysts before, but 6 (24%) had them after return. Questionnaires returned by 133 of the campers showed that 5% had an illness compatible with giardiasis within 2 weeks after their trip. These surveys show that campers exposed to mountain stream water are at risk of acquiring giardiasis.  相似文献   
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