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1.
2.
Studies of the rate of clearance of a gellan gum formulation (Gelrite) radiolabelled by the inclusion of technetium-99m labelled diethylenetriaminepentaacetic acid were carried out in volunteer subjects and in rabbits. Disposition was followed by gamma scintigraphy and compared with 0.5% w/v hydroxyethylcellulose (HEC) solution and isotonic saline administered to the same subjects. Clearance of all solutions was found to follow bi-exponential kinetics with differences in clearance rates between the two species studied. A significant retention of the gellan gum formulation compared to HEC (p = 0.006) or saline (p = 0.009) was noted in man, but not in the rabbit. In this latter species the HEC showed greater retention compared to Gelrite. The species-specific differences in the precorneal residence of the formulations are attributed to the different physiological responses following instillation of solutions into the eye. 相似文献
3.
This study retrospectively evaluated the outcome for patients undergoing herniorraphy for chronic groin pain due to posterior inguinal wall deficiency, and correlated the outcome with preoperative investigation findings. There were 47 patients (with a total of 52 herniorraphies) who were contacted by phone between six and 50 months post surgery. Subjects had a diagnosis of posterior inguinal wall deficiency made on history and clinical examination. Thirty seven patients had an ultrasound scan prior to the surgery (three bilateral) with a total of 40 symptomatic groins scanned. There were 26 abnormal scans (22 posterior inguinal wall deficiency and four hernias) and 14 normal scans. Twenty nine patients had a technetium-99m bone scan with 22 having increased uptake at the symptomatic pubic tubercle, while 13 had increased uptake at other sites in the groin. Seventy seven percent of patients had a full return to sport after surgery and the average time to return to sport was four months. There was no significant difference in outcome between subjects who had an abnormal ultrasound scan on the symptomatic side and those who had a normal scan. There was a significant difference in outcome between patients who had a bone scan with increased uptake at the symptomatic pubic tubercle and those who did not (p < 0.04). Our study supports previous research that good results can be obtained with surgery when posterior inguinal wall deficiency is the sole diagnosis. Ultrasound scan does not appear to aid in predicting surgical outcome, while the role of isotope bone scanning requires further study. 相似文献
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5.
In a prospective randomized clinical trial comprising 22 postmenopausal women with backache and a halisteretic spine with crush fracture(s), 12 women completed a 12-week therapy with sodium fluoride, calcium and calciferol and 10 with placebo. A statistically significant improvement (p less than 0.05), evaluated by a four-stage scale on pains, infirmity, and consumption of analgesics, was observed in the actively treated patients. 相似文献
6.
7.
The pharmacology of synthetic
- and
-epibatidine, an alkaloid originally characterized from frog skin, were studied in different behavioral tests in mice and rats. The two enantiomers have potent antinociceptive activity in mice using the tail-flick test, with an ED50 of 6.1 and 6.6 μg/kg for
- and
-epibatidine respectively. Epibatidine enantiomers were 200 × more potent than
-nicotine as an antinociceptive agent in mice after s.c. administration. Their analgesic effect was blocked by mecamylamine but not naloxone, an opiate antagonist. Both
- and
-epibatidine have high affinity (Ki 54.7 and 55.0 pM, respectively) for [3H]nicotine binding site in rat brain. In addition, they reduced mice locomotor activity and body temperature in a dose-dependent manner. In rats trained with nicotine (0.4 mg/kg), epibatidine enantiomers engendered nicotine-like responding in a dose-related manner with an ED50 of 1.00 and 0.93 μg/kg for
and
, respectively. The discriminative effect of
- and
-epibatidine in rats was blocked by mecamylamine but not by hexamethonium. As in binding results, there was no significant enantioselectivity for these effects in our study. 相似文献
8.
H J Odendaal R C Pattinson R du Toit D Grove 《Suid-Afrikaanse tydskrif vir geneeskunde》1988,74(1):19-21
Abruptio placentae occurred in 16 of 132 patients with severe pre-eclampsia who were admitted to an obstetric high-risk ward before 34 weeks' gestation. These 16 patients were compared with those who did not develop abruptio placentae. Systolic and diastolic blood pressure levels, proteinuria and birth weights did not differ significantly between the two groups. Apgar scores were significantly lower in the abruptio placentae group. There were 6 intra-uterine and 2 neonatal deaths in the abruptio placentae group (50% perinatal mortality (PNM] and 3 intra-uterine and 16 neonatal deaths in the other group (18% PNM). Four patients with abruptio placentae presented with abnormal fetal heart-rate patterns and 8 with abdominal pain. No warning signs were present in 3 patients and the fetal heart-rate pattern before delivery was not available in 1 patient. Abnormal fetal heart-rate patterns were present in 5 of the 8 patients who presented with pain. Abruptio placentae occurring in patients with severe proteinuric hypertension carries a high PNM. Frequent monitoring of the fetal heart rate sometimes helps to diagnose fetal distress before the clinical signs of abruption become apparent. 相似文献
9.
10.
Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation 总被引:9,自引:4,他引:9
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and
iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated
silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by
gradient centrifugation for use in assisted reproductive procedures.
Efficacy was assessed in terms of percentages of sperm recovery, sperm
vitality and motility, normal sperm morphology and normal sperm chromatin
condensation. No significant difference was found in the recovery of
spermatozoa for men with both normal sperm counts and oligozoospermia,
between PVP-coated and silane-coated particle solutions. Iodixanol had
significantly lower sperm recovery compared to the other products. Sperm
vitality, progressive motility, normal morphology and normal chromatin
condensation did not differ significantly between any of the sperm
isolation products.
相似文献