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991.
P A Lear 《Transplantation proceedings》1990,22(6):2441-2442
992.
993.
A 24-year-old man had unilateral gross hematuria that required nephrectomy. Pathological examination revealed massive intratubular hemorrhage and frequent deposition of an amorphous and homogeneous material positive for periodic acid, Schiff stain in the corticomedullary junction. This substance had the characteristics of Tamm-Horsfall protein and frequently herniated into the lumen of thin-walled veins of arcuate size. There was no apparent cause for the bleeding. To the best of our knowledge this is the third reported case with these peculiar findings and no apparent cause. We discuss some hypotheses as to the etiopathogenesis of this rare and intriguing condition. 相似文献
994.
M L Schwartzman P Martasek A R Rios R D Levere K Solangi A I Goodman N G Abraham 《Kidney international》1990,37(1):94-99
Cytochrome P450-dependent arachidonic acid metabolism in human kidney cortex from several postmortem subjects has been characterized. Using HPLC and GC/MS, four cytochrome P450-arachidonic acid metabolites were tentatively but not unequivocally identified as epoxyeicosatrienoic acid (EET), dihydroxyeicosatrienoic acid (DHT) and 19- and 20-hydroxyeicosatetraenoic acids, suggesting the involvement of two major cytochrome P450 enzymes, epoxygenase and omega/omega-1 hydroxylases. This pattern of metabolism was similar to that found in rabbit and rat kidneys. The formation of these metabolites was dependent on the presence of NADPH and inhibited by IgG of NADPH-cytochrome P450 (c) reductase. Immunologic studies of renal cytochrome P450 epoxygenase demonstrated that antibodies prepared against human-purified hepatic cytochrome P450 epoxygenase recognized renal enzyme protein and inhibited the enzyme activity by 92%. In contrast, control immunoglobulin did not inhibit renal cytochrome P450 epoxygenase. Antibody inhibition of renal cytochrome P450 epoxygenase demonstrated a degree of conservation of both enzyme proteins between liver and kidney. Antibodies against lauric acid omega/omega-1 hydroxylases (P450 omega) inhibited the formation of omega/omega-1 hydroxylase products, 19- and 20-HETEs. Identical qualitative patterns of arachidonic acid metabolites were observed in all cortical microsomes studied. Interindividual variations were observed in the cytochrome P450-dependent arachidonic acid metabolism, and the activities ranged from 0.031 to 5.027 nmol arachidonic acid converted/mg protein/30 min. which is about a 150-fold difference. However, when the specific activities for total cytochrome P450-dependent arachidonic acid metabolism were calculated, two separate groups could be distinguished, high and low metabolizers of arachidonic acid.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
995.
1. Effects of a novel imidazoindole derivative on cholinergic function were studied in isolated tissue preparations. 2. The compound demonstrated a dose-dependent (10(-11)-10(-9) potentiation (20-60%) of acetylcholine induced tension in guinea pig ileal tissue. 3. Increases in the size of end-plate potentials and nerve evoked muscle twitches were observed in frog nerve-skeletal muscle preparations. 4. Cholinesterase activity was not inhibited. 5. The results suggest that the compound has actions at the post-synaptic muscarinic receptor complex in smooth muscle and causes pre-synaptic increases in ACh release at the neuromuscular junction. 相似文献
996.
P Thomas 《British journal of hospital medicine》1990,44(2):133-135
997.
Mortality prognostic factors in chest injury 总被引:2,自引:0,他引:2
1,026 multiple trauma patients (P) were compared to P with chest injuries (PCT) (407). Severity indices were related to type of thoracic injury and mortality. The Injury Severity Score (ISS), Glasgow Coma Scale (GCS), Trauma Score (TS), CHOP, and the Respiratory Index (RI) were used. The mortality rate of P was 27.1% but increased to 32.9% for PCT (p less than 0.05). We noted that mortality rate was highly dependent on major chest trauma: 68.6% for flail chest (FC), 56% for lung contusion (LC), 42.3% for hemothorax (HA), and 38.1% for pneumothorax (PN). ISS and RI scores for PCT survivors were greater than ISS + RI scores for P survivors (p less than 0.05 and p less than 0.01). ISS values for LC, HA, and PN PCT survivors were greater than the ISS of P survivors (p less than 0.01). Nonsurviving PCTs, especially those with lung contusion, showed a highly significant increase in ISS and RI scores. 相似文献
998.
We report a case of recurrent calculi in a Kock pouch continent urinary diversion. An open operation was avoided by successfully excising the Marlex mesh and removing it with the associated calculi in an endoscopic fashion. 相似文献
999.
1000.
Summary The effect of distension on adrenergic innervation was investigated in the rat urinary bladder. Bladders were distended for 3 h by forced diuresis and ballon obstruction, and specimens were taken from the bladder dome, body and neck for the demonstration of glyoxylic acid-induced fluorescence of catecholamines. Depletion of catecholamines started after 10 h and was almost complete after 2 days. The fluorescence had recovered part way after 5–7 days and was practically normal after 21 days. Small, intensely fluorescent (SIF) cells in the ganglia continued to leak catecholamines throughout the 21-day study period. The primary clinical success of distension therapy for the treatment of unstable bladder may be at least partly due to a reversible disturbance in the function of the adrenergic nerves, which have an excitatory alpha-adrenergic dominance in such cases, but the persistent leakage from SIF cells raises the question of whether distension causes prolonged disturbances in bladder function. 相似文献