Contemporary treatment of thrombosed hemodialysis grafts.

Maintaining hemodialysis grafts remains a difficult problem. Before the early 1990s, graft declotting was usually performed in the surgical suite. Percutaneous declotting has been evolving since the mid-1980s.

Reteplase in the treatment of peripheral arterial and venous occlusions: a pilot study.

Purpose: Reteplase, a truncated mutant of tissue plasminogen activator, has been used successfully in the treatment of acute coronary occlusion, but, heretofore, it has not been investigated in the setting of peripheral vascular occlusion. Reteplase is a potential recombinant thrombolytic agent that may offer an appropriate alternative to currently employed plasminogen activators.

Materials And Methods: Over a 6-month period reteplase was used to treat peripheral vascular occlusions at five centers in the United States.

Methods of ovulation induction.

The results of ovulation induction in patients with ovulatory dysfunction were reviewed for a one year period. Eighty-six women were assigned to four groups: secondary amenorrhea, anovulation, oligo-ovulation, and luteal phase defect/short luteal phase (LPD). All patients were monitored with basal body temperature (BBT) graph, postcoital testing, and ultrasonic scanning of ovarian follicles.

Vertebral bone density in Scheuermann disease.

The densities of the trabecular bone of two or three lumbar vertebral bodies in twenty adolescents, twelve to eighteen years old, who had Scheuermann disease were measured by quantitative computed tomography. These densities were then compared with those for the same vertebrae of twenty age, sex, and race-matched adolescents who were examined by computed tomography because of trauma. The same scanner and phantom were used in all examinations.

The effect of limping on vertebral bone density: a study of children with tarsal coalition.

To determine whether limping is associated with decreased bone mineralization, the trabecular and integral bone densities (BDs) of 18 Caucasian children exhibiting computed tomographic evidence of tarsal coalition (14 boys, 4 girls, aged 9 years, 5 months to 16 years, 3 months) were compared with those of an age- and sex-matched control group. Patients with tarsal coalition had significantly lower trabecular (p less than 0.05) and integral (p less than 0.

Effect of sex steroids on peak bone density of growing rabbits.

To determine the effect of sex hormones on bone density (BD) during growth, longitudinal quantitative computed tomography (QCT) measurements were obtained in growing, castrated New Zealand White rabbits following administration of normal saline, testosterone, or estrogen from 6 wk of age until the time of skeletal maturity. Vertebral QCT densities increased during growth, were highest at the time of epiphyseal closure, and were significantly greater (P less than 0.001) in hormone-treated animals.

Peak trabecular vertebral density: a comparison of adolescent and adult females.

To determine when spinal bone density reaches its peak, the trabecular vertebral density was assessed, via quantitative computed tomography, among females from two age groups: (1) adolescents (aged 14-19 years; N = 24); and (2) young adults (aged 25-35 years; n =24). The adolescent girls had a higher mean trabecular vertebral density (P less than 0.01), suggesting that spinal density reaches its peak around the time of cessation of longitudinal growth and epiphyseal closure.

Osteoporosis in cystic fibrosis.

To determine if osteoporosis is prevalent among patients with cystic fibrosis, we compared the vertebral bone density measured by quantitative computed tomography in 57 such patients (29 male, 28 female, aged 3 to 21 years) with those of an age-, race-, and sex-matched control group of 57 healthy subjects. Patients with cystic fibrosis had significantly lower bone density (10% lower, p less than 0.001) than in controls.

Vertebral bone density in children: effect of puberty.

To determine changes in bone density during growth, trabecular vertebral density and an index of spinal cortical bone were measured with quantitative computed tomography in 101 children. The children were divided by age into three groups: prepubertal, indeterminate, and pubertal. Compared with prepubertal children, pubertal adolescents had significantly higher trabecular bone density and more compact bone in the spine (P less than .

Ontogeny of dopamine, serotonin and spirodecanone receptors in rat forebrain--an autoradiographic study.

Sections from freshly frozen neonatal rat brain, ages 0-21 days, were incubated with [3H]spiperone (SP). Initial studies characterized the binding sites for SP in terms of association and dissociation rates, saturability and pharmacology. The binding sites were found to be predominantly dopamine D2 receptors in sections centered in the striatum and these receptors were similar to receptors in adult brain.

The role of serotonergic neurons in dorsal raphe, median raphe and anterior hypothalamic pressor mechanisms.

The role of serotonergic neurons in the dorsal raphe and median raphe in the pressor response to electrical stimulation of these areas, and the contribution of these neurons to the pressor response to serotonin (5-HT) in the anterior hypothalamus-preoptic area (AH/PO) have been studied by the use of local injections of 5,7-dihydroxytryptamine (5,7-DHT), a neurotoxin selective for 5-hydroxytryptamine (5-HT). When blood pressure was recorded in urethane-anesthetized rats, selective lesions of 5-HT-containing neurons in the dorsal raphe nucleus reduced by 60% the pressor response to electrical stimulation (50 Hz, 100-150 microA, 0.3 msec pulse duration) of this nucleus.

May spina bifida result from an X-linked defect in a selective abortion mechanism?

It is suggested that the major genetic factor in determining the birth of children with neural tube defects may be a single X-linked gene. It acts as an X-linked dominant, not by producing neural tube defects, but by enabling the affected fetus to survive selective spontaneous abortion. This mechanism, mediated at the deciduoplacental junction, may be under the control of both maternal and fetal genes.