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71.
In deep layers of the cat motor cortex, we have investigated the properties of neurons displaying trans-synaptically induced bursts. In in vivo experiments, extracellularly recorded burst neurons were separated into two subtypes based on their dependence on stimulation sites, the medullary pyramid or the ventrolateral (VL) thalamic nucleus, from which bursts of 10-20 spikes were triggered. The spike amplitude attenuation and frequency adaptation during a burst were more prominent in pyramid-dependent burst neurons than in VL-dependent burst neurons. Intracellular recordings in in vivo experiments revealed that pyramid-dependent bursts emerged from a long-lasting depolarization, while each spike during a VL-dependent burst was narrow in half-width and was followed by a fast AHP, similar to fast spiking neurons. In in vitro slice experiments, intracellular recordings were obtained from neurons that displayed a burst of attenuated spikes emerging from a long-lasting depolarization, and were also obtained from fast spiking neurons. They were morphologically recovered to be multipolar cells with sparsely spiny dendrites and local axonal networks, suggesting that they are inhibitory interneurons. The multipolar neurons displaying bursts of attenuated spikes may mediate the recurrent inhibition of pyramidal tract cells.  相似文献   
72.
The authors examined the effect of bilateral jugular vein ligation (JVL) on local cerebral blood flow (CBF). Local CBF was measured in the neocortex of the frontal lobe over a 1-week period in 10 freely moving male rats. Measurements were taken with the hydrogen clearance method before and after the rat underwent either an operation of bilateral JVL or a sham operation. After the sham operation, blood flow values did not change significantly compared with preoperative values. Blood flow values decreased rapidly in rats with JVL. For 3 hours after surgery, JVL values were significantly lower (p <0.05) than preoperative values were, then gradually they recovered and reached preoperative values within 48 hours. Histopathologic study showed no remarkable parenchymal damages in the brain of rats with JVL. These results show that bilateral JVL produces a reversible decrease in the CBF and does not cause histopathologic brain damages.  相似文献   
73.
22-Oxacalcitriol ameliorates high-turnover bone and marked osteitis fibrosa in rats with slowly progressive nephritis. BACKGROUND: 22-Oxacalcitriol (OCT) is a unique vitamin D analogue with less calcemic activity than calcitriol, and it effectively suppresses parathyroid hormone (PTH) secretion in uremic rats. This study was performed to examine the long-term effect of intravenously administered OCT on high-turnover bone disease in model rats of slowly progressive renal failure. METHODS: Slowly progressive renal failure rats were made by a single injection of glycopeptide isolated from rat renal cortical tissues. At 250 days, glycopeptide-induced nephritis (GN) rats were divided into three groups with the same levels of serum creatinine and PTH, and they received either OCT (0.03 or 0.15 microg/kg body wt) or vehicle given intravenously three times per week for 15 weeks. RESULTS: Renal function of GN rats deteriorated very slowly but progressively, as assessed by the increase of serum creatinine concentration. At sacrifice, serum PTH levels, bone formation markers, bone resorption markers, and fibrosis volume were significantly elevated in vehicle-treated GN rats compared with those of sham-operated rats, suggesting the development of high-turnover bone disease with osteitis fibrosa. In contrast, in the GN-OCT 0.15 microg/kg group, these high PTH levels and high-turnover bone and fibrosis were significantly decreased. Such amelioration of bone abnormalities by OCT was not accompanied by either hypercalcemia or further deterioration of renal function. CONCLUSIONS: These data indicate that OCT may be a useful and safe agent not only for the suppression of PTH, but also for the amelioration of osteitis fibrosa and high-turnover bone without causing hypercalcemia in chronic dialysis patients.  相似文献   
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Hypertension in chronic progressive renal disease is a major clinical problem leading to renal function loss. We studied the influence of ambulatory blood pressure (ABP) and the effect of hypertension therapy on renal function in 116 patients with chronic glomerulonephritis. Patients were subdivided as hypertensive, normotensive and hypotensive according to the level of ABP and age. Hypotensive subjects showed improvement of renal function and normotensive subjects showed slower rate of progression of renal function loss than hypertensives, suggesting the adequate level of ABP was 100-125/55-75 mm Hg in patients less than 40 years old, 100-135/60-80 mm Hg in patients 40-60 years old, and 105-140/60-85 mm Hg in patients over 60 years, respectively. The renal protection of calcium antagonists was associated with achieving lower blood pressure levels, whereas the blood pressure level did not affect progression of renal function in patient treated with angiotensin converting enzyme (ACE) inhibitor. ACE inhibitor, but not calcium antagonists, showed a reduction of urinary protein excretion. Thus, the mechanisms of renal protection were different between ACE inhibitors and calcium antagonists.  相似文献   
77.
An anti-inflammatory factor (AIF) was highly purified from normal bovine serum. The purified AIF was a polysaccharide which was formed from a low molecular substance Pro-AIF by macromolecularization. AIF showed potent inhibitory activities against carrageenin induced edema in rats and PMN-leucocyte chemotaxis. It showed no inhibition in cutaneous reaction with serotonin, bradykinin or a mediator releaser compound 48/80. No inhibition was also observed in thermally induced pain, reversed passive Arthus reaction and adjuvant polyarthritis in rats. With these results, the role of AIF in inflammation was discussed.  相似文献   
78.
We observed the attacks of nystagmus in a case of infantile spasms and carried out overnight sleep polygraphy. The following findings were obtained:
  • 1 Awake time was prolonged to 56% of TIB, while sleep time was markedly shortened to 44% of TIB. Also REM sleep time was reduced to 20% of SPT and deep slow sleep (stage N3) was absent.
  • 2 Attacks of nystagmus were observed only during wakefulness. At first, fast wave bursts appeared in the right occipital area, and were followed by left-upward deviations of eyeballs, and then the attacks of counterclockwise right-downward rotatory nystagmus. Also the fast wave bursts were succeeded by spreading of fast waves to adjacent areas. At the same time, EMG exhibited elevated muscle action potentials of mentalis and biceps fernoris. During the attacks of nystagmus, there was alteration of respiratory movements.
In NREM sleep, both fast wave bursts and the attacks of nystagmus were not observed. In REM sleep, the fast wave bursts and eye movements were observed but the attacks of nystagmus did not appear. During the fast wave bursts, alteration of respiratory movements were observed. From the results of this study, it was presumed that the brain lesions of this case were extended with severe degree of damage in the great parts of brain containing Cerebral cortex and brain stem.  相似文献   
79.
Prolidase deficiency is an autosomal recessive disorder with highly variable symptoms, including mental retardation, skin lesions, and abnormalities of collagenous tissues. In Japanese female siblings with polypeptide negative prolidase deficiency, and with different degrees of severity of skin lesions, we noted an abnormal mRNA with skipping of 192 bp sequence corresponding to exon 14 in lymphoblastoid cells taken from these patients. Transfection and expression analyses using the mutant prolidase cDNA revealed that a mutant protein translated from the abnormal mRNA had an Mr of 49,000 and was enzymatically inactive. A 774-bp deletion, including exon 14 was noted in the prolidase gene. The deletion had termini within short, direct repeats ranging in size of 7 bp (CCACCCT). The "slipped mispairing" mechanism may predominate in the generation of the deletion at this locus. This mutation caused a 192-bp in-frame deletion of prolidase mRNA and was inherited from the consanguineous parents. The same mutation caused a different degree of clinical phenotype of prolidase deficiency in this family, therefore factor(s) not related to the PEPD gene product also contribute to development of the clinical symptoms. Identification of mutations in the PEPD gene from subjects with prolidase deficiency provides further insight into the physiological role and structure-function relationship of this biologically important enzyme.  相似文献   
80.
Continuous hyperthermic peritoneal perfusion (CHPP) with anticancer agents (mitomycin C and cisplatin) in warm saline was performed in patients with peritoneal dissemination of gastric cancer following resection of the primary lesion. The effect of CHPP was examined by a second-look operation. This study includes 41 cases of gastric cancer with peritoneal dissemination but without liver metastasis treated during the past 6 years. The overall median survival was 14.6 months to 64.2 months from CHPP to death and the 3-year survival rate was 28.5%. Second look surgery revealed a remarkable diminution in the degree of peritoneal dissemination in 7 (50%) of 14 patients with disappearance of ascites after only one course of CHPP in 7 (77.8%) of 9 patients. Long-term 3 year-survival was noted in 4 (9.8%) patients on CHPP. Side effects were renal insufficiency in 2 (5%) patients, leukopenia in 2 (5%) patients, and perforation of the small intestine in 1 (2%) patient. These results suggest the effectiveness of CHPP in the treatment of gastric cancer with peritoneal dissemination.
Resumen La perfusión hipertérmica continua (PHTC) con agentes anticancerosos (mitocina G y cisplatino) y solutión salina fue realizada en pacientes con cáncer gástrico con diseminación peritoneal después de resección de la lesión primaria, y el efecto de PHTC fue determinado mediante reexploración (operación de second look, OSL). La población de pacientes está constituída por 41 casos de cáncer gástrico con diseminación peritoneal pero sin metástasis hepáticas, tratdos en el curso de los últimos 6 años. La sobrevida media global fue de 437 dias (rango 28 a 1925 días) desde la PHTC hasta la muerte y la tasa de sobrevida a 3 años fue 28.5%. La OSL reveló una notoria disminución de la diseminación peritoneal en 7 (50%) de 14 casos y desaparición de la ascites después de sólo un ciclo de PHTC en 7 de 9 casos con ascitis. Sobrevida de 3 años ocurrió en 4 casos. Los efectos colaterales fueron insuficiencia renal en 2 casos (5%), leucopenia en 2 casos (5%) y perforación del intestino delgado en 1 caso (2%). Los anteriores resultados sugieren que la PHTC es eficaz en el tratamiento del cáncer gástrico con diseminación peritoneal.

Résumé La perfusion péritonéale continue hyperthermique (PPCH) avec des agents anticancéreux comme le mitomycine C et la cis-platine avec sérum physiologique chauffé a été instaurée lorsqu'une carcinose d'origine gastrique a été trouvée. Les effets de la PCH ont été évalués chez 16 patients lors d'un second-look (SL). Cette étude concerne 41 patients avec carcinose péritonéale sans métastase hépatique observés au cours des 6 dernières années. La survie globale médiane était de 437 jours (extrêmes 28 à 1925 jours): le taux de survie a 3 ans était de 28.5%. Les lésions avaient diminué de façon notable chez 7 (50%) de 14 patients. L'ascite a disparu dans 7 des 9 cas. Une survie à long terme (3 ans) a été notée dans 4 cas. Les effets secondaires ont été une insuffisance rénale dans 2 cas (5%), une leucopénie dans 2 cas (5%) et une perforation de l'intestin grêle dans un cas (2%). Les résultats suggèrent que la PPCH est efficace dans le traitement du cancer gastrique avec dissémination péritonéale.
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