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61.
A survey of directors of advanced educational programs in pediatric dentistry, identical to one conducted in 1979, was undertaken to examine the utilization of and indications for various physical restraint techniques. Updated results indicated that there is still a high acceptance of the hand-over-mouth (HOM) technique. Only 11.1% of programs never use the technique. However, the acceptance of airway restriction is significantly lower than in 1979. Program directors currently report increased situations in which other physical restraint techniques, such as the Papoose Board, are recommended. Despite the continued acceptance of physical restraint techniques, a significant number of directors report that they are less certain that these techniques do not induce psychological problems. Although the current survey data indicates that there may be a discrepancy between professional standards as espoused by program directors, and material standards, that discrepancy is greatest for those program directors with tenures in excess of 10 years. These directors were much more likely to believe that HOM was indicated in situations other than for the control of hysterical and tantrum-like behavior and were much less likely to tell the child why HOM was being used. Additionally, such directors were as likely to use airway restriction as were 1979 respondents, although directors with tenures of less than 10 years were significantly less likely to use airway restriction.  相似文献   
62.
Pharmacokinetics of intramuscularly administered ertapenem   总被引:3,自引:0,他引:3       下载免费PDF全文
Ertapenem (INVANZ) is a new once-a-day parental beta-lactam antimicrobial agent that has been shown to be highly effective as a single agent for treatment of various community-acquired and mixed infections. The plasma pharmacokinetics of a 1-g intramuscular (i.m.) dose was compared with those of a 1-g intravenous (i.v.) dose infused over 30 min, the recommended rate of i.v. infusion for comparison, and over 120 min, which more closely mimicked the time course for absorption of the i.m. form. In a three-period crossover study (Part A), 26 healthy subjects received single doses of ertapenem administered i.m., i.v. infused over 30 min, and i.v. infused over 120 min. Blood for ertapenem analysis was collected over 24 h postdose for each treatment. In Part B, these fasted subjects received a 1-g i.m. dose of ertapenem once daily for 7 days. Following a 1-g i.m. dose and a 1-g i.v. dose infused over 120 min, the geometric mean area under the concentration curve from hour 0 to infinity (AUC(0- infinity )) was 541.8 micro g. hr/ml following i.m. administration and 591.4 micro g. hr/ml following a 120-min infusion; the geometric mean ratio was 0.92 with a 90% confidence interval of 0.88 to 0.95. The geometric mean AUC(0- infinity ) was nearly identical when 1-g doses were infused over 30 or 120 min. Although the maximum concentration of drug in serum was somewhat lower following i.m. administration than following i.v. administration, the shape of the plasma concentration profiles was roughly comparable at later time points. Ertapenem did not accumulate after multiple 1-g i.m. daily doses over 7 days. The geometric mean ratio for AUC(0-24) (day 7/day 1) was 0.98 with a 90% confidence interval of 0.94 to 1.02. Thus, the relative bioavailability of the 1-g i.m. dose was 92%. Ertapenem does not accumulate following multiple daily 1-g i.m. doses over 7 days.  相似文献   
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Pharmacokinetics of ertapenem in healthy young volunteers   总被引:3,自引:0,他引:3       下载免费PDF全文
Ertapenem (INVANZ) is a new once-a-day parenteral beta-lactam antimicrobial shown to be effective as a single agent for treatment of various community-acquired and mixed infections. The single- and multiple-dose pharmacokinetics of ertapenem at doses up to 3 g were examined in healthy young men and women volunteers. Plasma and urine samples collected were analyzed using reversed-phase high-performance liquid chromatography with UV detection. Ertapenem is highly bound to plasma protein. The protein binding changes from approximately 95% bound at concentrations of <50 micro g/ml to approximately 92% bound at concentrations of 150 micro g/ml (concentration at the end of a 30-min infusion following the 1-g dose). The nonlinear protein binding of ertapenem resulted in a slightly less than dose proportional increase in the area under the curve from 0 h to infinity (AUC(0- infinity )) of total ertapenem. The single-dose AUC(0- infinity ) of unbound ertapenem was nearly dose proportional over the dose range of 0.5 to 2 g. The mean concentration of ertapenem in plasma ranged from approximately 145 to 175 micro g/ml at the end of a 30-min infusion, from approximately 30 to 34 micro g/ml at 6 h, and from approximately 9 to 11 micro g/ml at 12 h. The mean plasma t(1/2) ranged from 3.8 to 4.4 h. About 45% of the plasma clearance (CL(P)) was via renal clearance. The remainder of the CL(P) was primarily via the formation of the beta-lactam ring-opened metabolite that was excreted in urine. There were no clinically significant differences between the pharmacokinetics of ertapenem in men and women. Ertapenem does not accumulate after multiple once-daily dosing.  相似文献   
65.
Stromal cell-associated erythropoiesis   总被引:5,自引:0,他引:5  
Tsai  S; Sieff  CA; Nathan  DG 《Blood》1986,67(5):1418-1426
A novel cover slip-transfer culture system was designed to study the functional roles of stromal cells in hemopoiesis, particularly erythropoiesis. Human bone marrow stromal cell colonies were allowed to develop on small glass cover slips in liquid medium. The cover slips, along with the stromal cell colonies and progenitors attached to them were then transferred to a new tissue culture dish and overlaid with methylcellulose culture medium. No exogenous colony-stimulating factors except erythropoietin were supplied. Large erythroid bursts, comprising multiple subcolonies, developed on the stromal cells. In order to determine if stromal fibroblasts together with erythropoietin and serum proteins could support erythroid development, human bone marrow cells depleted of monocytes, macrophages, and T lymphocytes were allowed to adhere to monolayers of a homogeneous fibroblastoid human stromal cell strain ST-1 grown on cover slips. The cover slips were then washed to remove nonadherent cells, transferred to a new culture dish, and overlaid with methylcellulose culture medium containing fetal calf serum and erythropoietin. In this modified system as well, primitive erythroid progenitors migrated extensively on and within the stroma to form huge colonies of hemoglobinized erythroblasts that proceeded to enucleate. Our results indicate that (1) ST-1 cells together with serum proteins and erythropoietin can support the development of large erythroid bursts; (2) erythroid progenitors and precursors adhere to and migrate on and within the extracellular matrix elaborated by ST-1 cells; (3) erythroid progenitors are more adherent to the ST-1 cells or the extracellular matrix than are the more mature cells and possibly the myeloid progenitors.  相似文献   
66.
Muscle and nerve injuries in the hand may be difficult to detect and diagnose clinically. Two cases are reported in which magnetic resonance imaging showed ulnar nerve injury and intrinsic hand muscle denervation. The clinical, anatomical and radiological features of injury to the deep motor branch of the ulnar nerve and associated muscle denervation are discussed and illustrated.  相似文献   
67.
Brachial plexus: demonstration at US   总被引:5,自引:0,他引:5  
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