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1.
The effect of flow rate and type of i.v. solution container on adsorption of diazepam to i.v. administration systems was studied. Diazepam solutions were prepared in 500 mL of 0.9% sodium chloride injection in glass, polyethylene, and polyvinyl chloride (PVC) containers to a final theoretical concentration of 50 micrograms/mL. PVC administration sets were attached to the containers, and diazepam solution was infused at flow rates of 30, 45, 60, 90, and 120 mL/hr. Solution samples were taken initially and at 0.25, 0.5, 0.75, 1.00, 1.50, 2.00, 3.00, and 4.00 hours after infusion of the first 5 mL of solution through the system. Three infusion trials were performed using each type of container. Adsorption of diazepam to each type of container was evaluated by serial measurements of diazepam concentration over a 168-hour period using five containers of each type. The effect of shaking the container on diazepam adsorption to PVC containers was tested by comparing concentrations in five containers that were shaken during a two-hour period with concentrations in five unshaken containers. Diazepam concentrations were measured spectrophotometrically in duplicate. Diazepam concentrations in glass containers remained unchanged throughout the 168-hour study period; concentrations decreased by about 5% in polyethylene containers and as much as 75% in PVC bags. Shaking increased diazepam adsorption to the PVC container. In the infusion trials, the percentage of diazepam adsorbed increased as flow rate decreased. The amount of diazepam adsorbed to the i.v. administration system was ore dependent on flow rate and infusion time than on the type of container used.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Successful internal arterial embolization with steel coils in life-threatening bleeding after femoral fracture is described in an older patient.  相似文献   
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Weight-bearing exercise has been shown to maintain or increase bone mass in younger as well as older individuals but the mechanisms by which mechanical loading affects bone metabolism are not known in detail. Twelve postmenopausal women participated in a single bout of brisk walking (50% of VO2 max) for 90 minuttes. Calciotropic hormones and markers of type I collagen formation (PICP) and degradation (ICTP) were measured before the exercise, and 1, 24, and 72 hours following the exercise. Total body bone mineral content (BMC) and density (BMD) were measured by dual energy X-ray absorptiometry (DXA). Brisk walking did not induce any significant changes in the concentrations of ionized calcium, parathyroid hormone (PTH), calcitonin, or osteocalcin. A significant increase of PICP was noted 24 and 72 hours (P<0.01) after exertion and a significant decrease in the concentration of serum ICTP at 1 hour (P<0.05) was followed by an increase at 72 hours (P<0.001). There was no significant difference between the increases in the concentrations of PICP and ICTP at 72 hours. Strong inverse correlations between the basal levels of PTH and BMD (r=−0.78;P<0.01) as well as between osteocalcin and BMD (r=−0.83;P<0.01) were noticed. The changes in serum levels of bone collagen markers indicate an altered bone collagen turnover due to this moderate endurance exercise. The results also support the fact that serum levels of PTH as well as those of osteocalcin are associated with total body BMD in postmenopausal women.  相似文献   
4.
A child with multiple anomalies, including growth retardation, a left-sided diaphragmatic hernia with lung hypoplasia, and cerebral malformations is described. Cytogenetic investigation demonstrated a deletion of the distal part of one chromosome 15, del(15)(q24qter), an aberration not previously described. Family studies revealed that the mother had a balanced translocation, t(6;15)(p25;q24). Two of her subsequent pregnancies resulted in abortions after prenatal diagnosis: one fetus was trisomic for 15q24→qter, while the other had monosomy 15q24→qter and a left-sided diaphragmatic hernia similar to the first child.  相似文献   
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76 cases of secondary myelodysplasia (sMDS) and acute non-lymphocytic leukemia (sANLL) were cytogenetically analyzed. Among the 36 sMDS patients, 13 (36%) had only normal karyotypes whereas 23 (64%) displayed clonal chromosomal abnormalities. The most common aberrations were -7, 5q-, -5, and +8. In 10 patients (43% of the cytogenetically aberrant cases), clones with only one anomaly, mostly 5q- or -7, were found. Of the 40 sANLL patients, normal karyotypes were detected in 10 (25%). Among the 30 (75%) abnormal cases, the most frequent aberrations were -7, -5, +8, 7q-, -17, and +21. 12 patients (40%) had clones with single abnormalities, most often -7. In 4 sANLL patients cytogenetically unrelated clones were detected. A survey of all previously published secondary hematologic neoplasias reveals that the most frequent abnormalities in sMDS are -7 (41%), 5q- (28%), and -5 (11%), followed by der(21q), +8, 7q-, der(12p), t(1;7), -12, -17, der(17p), der(3p), der(6p), and -18. Clones with single aberrations have been found in 45% of the cases and cytogenetically unrelated clones have been described in 6%. The most common abnormalities in sANLL are -7 (38%), 5q- (17%), -5 (15%), +8 (13%), and -17 (11%), followed by der(3q), der(11q), der(12p), -21, 7q-, -18, der(3p), der(17p), +21, der(21q), der(6p), and -16. 38% of the sANLL patients have had clones with only one aberration and 3% have had unrelated clones. The frequencies of these nonrandom abnormalities in sMDS and sANLL are thus remarkably similar - the only exception appears to be 5q-, which is more common in sMDS. Also the mean number of abnormalities per case is similar - 5.3 in sMDS and 5.6 in sANLL. When the incidences of characteristic cytogenetic abnormalities were correlated with the type of previous therapy, -7 was found to be more frequent in sMDS and sANLL patients who had been exposed to chemotherapy whereas 5q- was associated with previous exposure to ionizing radiation in sMDS patients.  相似文献   
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We evaluated the safety and efficacy of a 72-h epidural infusion of ropivacaine and measured the impact of adding fentanyl 2 microg/mL to the required infusion rate, on the quality of postoperative pain relief and the incidence of side effects, after colonic surgery. One hundred fifty-five patients scheduled for elective colonic surgery were randomized in this trial. Epidural infusions of ropivacaine 2 mg/mL with fentanyl 2 microg/mL (R + F) and without fentanyl (R) were commenced during surgery and continued for 72 h postoperatively. This was a prospective, randomized, double-blinded, multi-center trial. The median infusion rate required was less in the R + F group (9.3 vs 11.5 mL/h, P < 0.001). Median pain scores at rest and on coughing were lower in the R + F group (P < 0.0001). The incidence of hypotension was more in the R + F group (P = 0.01). Time to readiness for discharge was delayed in the R + F group (median 6.6 vs 5.5 days, P = 0.012). The addition of fentanyl to ropivacaine resulted in decreased infusion rates and enhanced pain control; however, adverse effects were increased and readiness to discharge was delayed. IMPLICATIONS: Epidural infusions of ropivacaine with and without fentanyl were administered to patients to control pain after colonic surgery. Patients who received ropivacaine with fentanyl had better pain control, increased side effects, and delayed readiness to discharge. This study questions the value of adding opioids to epidural infusions of local anesthetics.  相似文献   
10.
OBJECTIVE: To study patients with autosomal recessive pseudohypoaldosteronism type 1 and to relate pulmonary disease to gene mutations of the epithelial sodium channel (ENaC). STUDY DESIGN: Clinical and laboratory data were collected from 4 Swedish patients with pseudohypoaldosteronism type 1. The genes for ENaC and cystic fibrosis transmembrane conductance regulator were analyzed for mutations with methods including DNA sequencing. RESULTS: Three novel mutations were found in the alpha-gene of ENaC, 2 frameshifts (1449delC and 729delA) and 1 missense mutation resulting in the substitution of leucine for serine 562 in the alpha-chain (S562L). The 1449delC mutation was found in all patients in either homozygous or heterozygous form and seems to be the predominant cause of pseudohypoaldosteronism in Sweden. The allele coding for S562L also contained a transition converting tryptophan 493 to arginine (W493R), which seems to be a rare polymorphism. All patients had pulmonary symptoms to various degrees. The bacterial findings resembled, to some extent, those in cystic fibrosis, but development of chronic lung disease and progressive decline in lung function were not observed. CONCLUSIONS: Genetic deficiencies of the alpha subunit of the ENaC are associated with prominent lung symptoms, which are, however, clearly different from those in cystic fibrosis.  相似文献   
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