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991.
M Ferin PW Carmel MP Warren RL Himsworth AG Frantz MR Nocenti 《Canadian Metallurgical Quarterly》1976,151(2):428-433
Rhesus monkeys, sedated with phencyclidine hydrochloride (Sernylan), were quieted for prolonged periods of time, while maintaining somatic reflexes, muscle tone, and respiration. Brief daily periods of sedation did not interfere with the menstrual cycle. Prolonged sedation, however, interfered with the experimentally estrogen-induced LH surge, but not with the inhibitory action of estrogen on LH tonic secretion. Pulsatile release of LH, GH, and prolactin persisted even under prolonged sedation. The secretion of prolactin in response to the administration of TRH was increased in animals sedated with phencyclidine. 相似文献
992.
MR Robinson MB Shetty B Richards J Bastable RW Glashan PH Smith 《Canadian Metallurgical Quarterly》1977,118(6):972-973
Of 48 patients with bladder tumors treated with intravesical epodyl 17 have shown a complete remission at some stage of treatment, although several have relapsed later. Partial remission occurred in 20 patients and 11 have shown no improvement or the lesions have progressed. Epodyl is used best as an adjunct to transurethral resection or diathermy of T1 bladder lesions. Even in patients who do not show complete remission epodyl may reduce the incidence of recurrence and the number of lesions. It is useful when rapid recurrence of T1 bladder tumors prevents control by resection or diathermy and it also is beneficial as an emergency measure to control hematuria. Complications are not infrequent and may be severe occasionally. Bone marrow depression has been seen in 2 patients whose bladders showed extensive carcinoma in situ. 相似文献
993.
The method of polar coordinate mapping of lesions on the aortic wall around orifices was used to study the effect of unilateral nephrectomy on sudanophilic lesions in rabbits. Four groups of six rabbits each were studied. Group I had a right nephrectomy with a short renal artery stump. Group II had a sham right nephrectomy. Group III had a left nephrectomy with a short renal artery stump and Group IV a sham left nephrectomy. All groups were allowed to recover for one week and were then fed rabbit chow enriched with 2% cholesterol and 6% corn oil for a four-week period. Groups I and III showed a marked alteration in lesions around the stump with both proximal and distal peaks. Group I also showed the development of skewing of the left renal lesion to the left, presumably because of a change in aortic flow due to removal of the proximal right renal flow. The right renal artery had a lesion skewed to the right; this was not altered by left nephrectomy and was probably due to coeliac flow. The data provides strong evidence that sudanophilic lesions in rabbit aortas are altered by local flow disturbances. 相似文献
994.
An ac technique for measuring magnetothermal conductivities using frequency crossing has been developed and shows a 13-fold increase in signal-to-noise ratio over the conventional dc technique. The ac technique employs low-frequency field modulation coupled with phase-sensitive detection and a 45-fold improvement in signal-to-noise ratio may be obtained by modulation over the half-width of the frequency crossing signal. A further increase of approximately 3 would be obtainable by increasing the modulation frequency and overcoming technical problems. The limit of detection and instrument revolution may be as low as 10 in. spins and a few megahertz, respectively. 相似文献
995.
K van Besien KA Sobocinski PA Rowlings SC Murphy JO Armitage MR Bishop OK Chaekal RP Gale JP Klein HM Lazarus PL McCarthy JM Raemaekers J Reiffers GL Phillips AV Schattenberg LF Verdonck JM Vose MM Horowitz 《Canadian Metallurgical Quarterly》1998,92(5):1832-1836
Advanced low-grade lymphomas are usually incurable with conventional-dose chemotherapy. It is uncertain whether cures are possible with high-dose therapy and bone marrow transplant from a human leukocyte antigen (HLA)-identical sibling. We sought to determine the outcome of HLA-identical sibling bone marrow transplants in advanced low-grade lymphoma in an observational study of 113 patients conducted at 50 centers participating in the International Bone Marrow Transplant Registry (IBMTR). The median patient age was 38 years (range, 15 to 61). Eighty percent had stage IV disease at the time of transplantation. The median number of prior chemotherapy regimens was two (range, 0 to 5). Thirty-eight percent had refractory disease and 29% a Karnofsky performance score (KPS) less than 80%. All patients underwent allogeneic bone marrow transplantation from a HLA-identical sibling donor. The conditioning regimen included total-body irradiation (TBI) in 82% of patients; cyclosporine was used for graft-versus-host disease prophylaxis in 74%. Survival, disease-free survival, recurrence rate, treatment-related mortality, and causes of death were determined. Three-year probabilities of recurrence, survival, and disease-free survival were 16% (95% confidence interval [CI], 9% to 27%), 49% (95% CI, 39% to 60%), and 49% (95% CI, 39% to 59%), respectively. Higher survival was associated with pretransplant KPS >/=90%, chemotherapy-sensitive disease, use of a TBI-containing conditioning regimen, and age less than 40 years. We conclude that high-dose therapy followed by transplantation from a HLA-identical sibling leads to prolonged survival in some patients with advanced low-grade lymphoma. Most mortality is treatment-related, and recurrences are rare. 相似文献
996.
E Rogers S Teahan H Gallagher MR Butler R Grainger TE McDermott JA Thornhill 《Canadian Metallurgical Quarterly》1998,159(3):851-854
PURPOSE: Owing to the risk of future malignancy, many postpubertal male subjects presenting with unilateral cryptorchidism undergo orchiectomy rather than orchiopexy. We examined the incidence of spermatogenesis and carcinogenesis in whole orchiectomy specimens removed from postpubertal cryptorchid male subjects. We review the concept that orchiectomy is justifiable in these patients. MATERIALS AND METHODS: A total of 52 patients with postpubertal cryptorchidism (unilateral in 48, bilateral in 4) were retrospectively analyzed from 1984. Patient age ranged from 15 to 66 years (mean 26). Six patients presented with primary infertility (unilateral in 3, bilateral in 3). The undescended testicles were palpable in 32 cases (62%). All patients underwent unilateral orchiectomy and whole specimens were examined histologically. RESULTS: Histology showed normal spermatogenesis in only 1 orchiectomy specimen, while 15 had maturation arrest, 6 testicular agenesis and 30 seminiferous tubular atrophy and/or Sertoli-cell-only syndrome with no spermatogenesis. The location of the undescended testis was the superficial inguinal pouch in 32 cases, inguinal canal in 6 and inside the deep ring in 8. Absent spermatogenesis was significantly associated with a high level of maldescent and with increasing age. Two patients (4%) had carcinoma in situ of the testicle. Torsion of an undescended testicle occurred in 1 patient (2%). CONCLUSIONS: This analysis of cryptorchid testes in postpubertal male subjects confirms that the majority cannot contribute to fertility, have significant malignant potential and may undergo torsion. Therefore, orchiectomy remains the treatment of choice for the majority of postpubertal male subjects presenting with unilateral cryptorchidism. 相似文献
997.
998.
999.
Previously, we have demonstrated that chronic exposure to immobilization (IMO) did not modify the influence of catecholamines on active behaviour of rats in the holeboard, but clearly increased the role of these amines in the forced swimming test (FST). In the present experiment, it was studied whether or not chronic IMO altered the role of dopamine in the two tests. Adult male Sprague-Dawley rats were left either undisturbed or subjected daily to 2 h of IMO stress for 12 days. On the following day, half of the rats were administered saline and the others the dopamine antagonist haloperidol (0.5 mg/kg). Then the rats remained undisturbed in the animal room (controls) or were subjected to acute IMO for 2 h. Finally, all animals were exposed consecutively to the holeboard (4 min) and the FST (5 min). In non-chronically stressed rats, acute IMO depressed behaviour in the holeboard but not in the FST. In chronic IMO rats the inhibitory effect of acute IMO on holeboard activity was slightly reduced as compared to controls. Acute IMO increased struggling in rats previously exposed to chronic IMO but did not alter struggling in non-chronically stressed rats. Whereas the inhibition caused by haloperidol treatment in the active behaviour of rats in the holeboard was not altered by chronic IMO, the inhibitory effect of haloperidol in the active behaviour of rats in the FST was greater after chronic IMO, particularly in rats also subjected to acute IMO. These data suggest that chronic IMO stress potentiates the role of dopamine in a specific behavioural task such as the FST and adds support to the previously published data demonstrating enhanced behavioural and neurochemical responses to dopamine-related drugs after chronic stress. 相似文献
1000.
JW Lowenthal JJ York TE O''Neil RA Steven DG Strom MR Digby 《Canadian Metallurgical Quarterly》1998,63(1-2):191-198
The time course of incorporation of [14C]arachidonic acid and [3H]docosahexaenoic acid into various lipid fractions in placental choriocarcinoma (BeWo) cells was investigated. BeWo cells were found to rapidly incorporate exogenous [14C]arachidonic acid and [3H] docosahexaenoic acid into the total cellular lipid pool. The extent of docosahexaenoic acid esterification was more rapid than for arachidonic acid, although this difference abated with time to leave only a small percentage of the fatty acids in their unesterified form. Furthermore, uptake was found to be saturable. In the cellular lipids these fatty acids were mainly esterified into the phospholipid (PL) and the triacyglycerol (TAG) fractions. Smaller amounts were also detected in the diacylglycerol and cholesterol ester fractions. Almost 60% of the total amount of [3H]Docosahexaenoic acid taken up by the cells was esterified into TAG whereas 37% was in PL fractions. For arachidonic acid the reverse was true, 60% of the total uptake was incorporated into PL fractions whereas less than 35% was in TAG. Marked differences were also found in the distribution of the fatty acids into individual phospholipid classes. The higher incorporation of docosahexaenoic acid and arachidonic acid was found in PC and PE, respectively. The greater cellular uptake of docosahexaenoic acid and its preferential incorporation in TAG suggests that both uptake and transport modes of this fatty acid by the placenta to fetus is different from that of arachidonic acid. 相似文献