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101.
102.
OBJECTIVES: To document the effects of pelvic radiotherapy on bowel, bladder, and sexual function, as reported by the patient. METHODS: A confidential questionnaire was distributed to 202 prostate cancer patients. Mean age was 70 years (range, 49 to 87) and mean follow-up was 33 months (range, 12 to 72). Radiation was given by a standard four field box technique on a linear accelerator to 60 to 66 Gy over 6.5 weeks. Treatment was limited to the prostate and seminal vesicles for small well-differentiated tumors, but otherwise included internal and external iliac nodes. RESULTS: Responses were obtained from 192 patients (95%). No or mild change in bowel function was reported by 64% of patients, 25% reported moderate change, and 11% reported severe change. Rectal urgency was a concern for 20%, and 5% reported fecal soiling in the preceding 6 months. Hematochezia at least once a week was reported by 9% and daily by 5%. Frequent hematochezia decreased from 17% in the second and third post-treatment years to 4% after 3 years (P = 0.02). Transfusions or laser surgery for proctitis was required by 4%. No patient required a colostomy for rectal complications. Urinary stream was unchanged or improved for 83%. Nocturia was unchanged or improved in 70%. Some form of protection for urinary incontinence was required by 2%, and 0.5% noted frequent hematuria and 2% moderate to severe dysuria. Potency prior to radiotherapy was reported by 82% and was lost following radiotherapy in 35%. Technical factors, including treatment volumes and total dose, did not correlate to the risk of moderate or severe complications. CONCLUSIONS: The sequelae of pelvic radiotherapy as viewed from the patient's perspective reveal a major alteration in bowel function in 11%, significant bladder symptoms in 4%, and loss of potency in 35%. 相似文献
103.
MN Sabbagh RT Reid J Corey-Bloom TS Rao LA Hansen M Alford E Masliah A Adem GK Lloyd LJ Thal 《Canadian Metallurgical Quarterly》1998,105(6-7):709-717
The loss of neocortical synapses that occurs in Alzheimer's disease (AD) has been shown to correlate with cognitive decline. In addition, marked losses in the cholinergic system in AD, specifically choline acetyltransferase (ChAT) activity and high affinity presynaptic neuronal nicotinic cholinergic receptors (nAChRs), have also been described. We hypothesized that in AD, the loss of [3H]-ligand binding to nAChRs, which are largely presynaptic, would correlate with changes in two other presynaptic markers: synaptophysin (Syn), a measure of synaptic density, and ChAT activity. The midfrontal (MF) cortex of 36 autopsy confirmed (NIA and CERAD criteria) AD patients (mean death age +/- SD 80.1 +/- 8.4 years) who met NINDS-ADRDA criteria for a clinical diagnosis of probable or possible AD, and 11 nondemented controls (mean death age +/- SD 77.9 +/- 8.0) were examined. Synapse counts were quantified by a dotimmunobinding assay for Syn. ChAT activity was assessed by standard biochemical assays. Nicotinic cholinergic receptor binding was assayed using the high affinity nicotinic agonist [3H]-(+/-)-epibatidine ([3H]-EPI). The mean +/- SD Syn in AD (83.4 +/- 31.9 arbitrary units (AU)/mg protein) was significantly lower than controls (126.1 +/- 19.9, p = 0.0003; t-test). The mean ChAT activity in AD (139.0 +/- 75.6 nmol ACh/hr/100 mg protein) was significantly lower than controls (219.6 +/- 70.8, p = 0.004). The mean [3H]-EPI total binding in AD (6.2 +/- 2.8 fmol/mg protein) was significantly lower than controls (14.8 +/- 3.2; p < 0.0001). Syn correlated with [3H]-EPI binding in AD (r = 0.48, p = 0.006; Pearson) but ChAT did not (r = -0.20, p = 0.34). We conclude that loss of high affinity nAChR binding correlates with loss of synapses in AD. The lack of correlation between [3H]-EPI binding and ChAT activity suggests that the targeted receptor populations may not be located exclusively on cholinergic neurons. 相似文献
104.
将可视化思想引入到设计计算中,采用数据可视化技术、COM接口技术,以VC语言为基础编制程序,进行桥式起重机起升机构的设计。设计过程开放,可按照个人需要进行交互设计,用户可以清楚地看到参数、设计指标的变化和最后自动生成的计算说明书。 相似文献
105.
Y Huang T Yonetani A Tsuneshige BM Hoffman GK Ackers 《Canadian Metallurgical Quarterly》1996,93(9):4425-4430
Hybridization experiments between normal Hb tetramers (Fe2+ Hb) and those with four metal-substituted hemes (i.e., replacement of Fe2+ by Co2+, Mg2+, Mn2+, Mn3+, Ni2+, or Zn2+) have revealed unexpected behavior. These homometallic Hbs have previously served as models that mimic the deoxy or oxy properties of normal Fe2+ Hb. In this study, hybrids were composed of one alpha 1 beta 1 dimer that is metal-substituted at both hemes, in association with a second dimer alpha 2 beta 2 that has normal Fe2+ hemes. Both metal-substituted subunits are unligated, whereas the two Fe2+ subunits either are both unligated or both ligated with O2, CO, or CN. It was found that four of the metal-substituted Hbs (Mg2+ Hb, Mn2+ Hb, Ni2+ Hb, and Zn2+ Hb) did not form detectable amounts of heterometallic hybrids with normal Fe2+ Hb even though (i) their homometallic parents formed tight tetrameric complexes with stabilities similar to that of Fe2+ Hb and (ii) hybrids with metal substitution at both alpha sites or both beta sites are known to form readily. This striking positional effect was independent of whether the normal Fe2+ hemes were ligated and of which ligand was used. These findings indicate that surprisingly large changes in tetramer behavior can arise from small and subtle perturbations at the heme sites. Possible origins of these effects are considered. 相似文献
106.
107.
p53 transactivates the expression of a variety of genes by binding to specific DNA sequences within the promoter. We have investigated the ability of wild-type p53 and a non-DNA binding p53 mutant to activate the hepatocyte growth factor/scatter factor (HGF/SF) promoter using chloramphenicol acetyltransferase reporter constructs. We also used deletion sequences of the HGF/SF promoter to identify which regions, if any, were responsible for p53 binding. Our results show that wild-type but not mutant p53 activates the HGF/SF promoter when using -3000 and -755 bp upstream of the HGF/SF gene. This activation is lost when promoter sequences covering -365 and -239 bp are used. Analysis of the DNA sequence between -365 and -755 bp shows one putative p53 half-site with 80% homology to the consensus sequence and another half-site 3 bases downstream of this with 100% homology to the consensus sequence. In contrast to previously identified p53 binding DNA sequences, the downstream half-site is inverted. We propose that the HGF/SF promoter can be activated by wild-type p53 in vivo and that this could be as a result of a novel form of sequence-specific DNA binding. 相似文献
108.
GK Matheson A Knowles D Guthrie D Gage D Weinzapfel J Blackbourne 《Canadian Metallurgical Quarterly》1997,29(5):823-828
1. The effects of ipsapirone, nefazodone, tiaspirone, BMS-20661, buspirone and gepirone on the hypothalamic-pituitary-adrenal (HPA) axis were studied. These drugs were selected because they have serontonin 1A (5-HT1A) receptor-binding capability and have the potential for therapeutic activity in the treatment of major affective or anxiety disorders or both. 2. Plasma corticosterone level was used as the end point for determining the effect of each drug on the HPA axis. Each drug increased the plasma corticosterone levels in a dose-dependent manner. The ED50 values were 0.8 mg/kg for BMS-20661, 3.5 mg/kg for gepirone, 3.9 mg/kg for buspirone, 5.3 mg/ kg for tiaspirone, 10.5 mg/kg for ipsapirone and 73.5 mg/kg for nefazodone. Ipsapirone and buspirone were more efficacious than the other four drugs. 3. The effect of a 10-mg/kg (35 mg/kg for nefazodone) test dose of each drug reached a peak between 30 min and 1 hr, and plasma corticosterone levels generally returned to control levels after 2 hr. 4. When the drugs were given 30 min before decapitation, in conjunction with a rotatory stress, BMS-20661 significantly inhibited the stress-induced rise, whereas ipsapirone and gepirone caused a significant increase in plasma corticosterone levels. However, when the drugs were given 2 hr before decapitation, nefazodone caused a significant decrease, whereas ipsapirone, BMS-20661 and gepirone produced significant increases in HPA axis activity. An 0800 hr dose of 0.1 mg/kg of dexamethasone suppressed the 1500 hr HPA activity by 73.1%. The 0.1-mg/kg dose of dexamethasone significantly reduced the drug-activated HPA axis activity of all of the drugs from their saline-control levels. The rank order, from least to greatest inhibitory effect, produced by this dexamethasone treatment on the drug-control levels was gepirone (-42.6%), tiaspirone (-48.9%), buspirone (-56.1%), nefazodone (-68.5%), insapirone (-70.0%), and BMS-20661 (-74.3%). 相似文献
109.
110.
Acute choroidal ischemia as a complication of photocoagulation 总被引:2,自引:0,他引:2
MH Goldbaum SO Galinos D Apple GK Asdourian K Nagpal L Jampol MB Woolf B Busse 《Canadian Metallurgical Quarterly》1976,94(6):1025-1035
Acute choroidal vascular insufficiency as a complication of photocoagulation has been little noticed. In 17 eyes of 16 patients photocoagulated with either xenon or argon sources for proliferative sickle cell retinopathy, gray lesions of the fundus developed peripheral to the photocoagulation sites. Histologic examination of similar gray lesions produced in monkeys showed necrosis and atrophy of the outer half of the retina. Intense photocoagulation of the human fundus, even with smaller spot sizes, may occlude a choroidal artery, producing separate gray lesions of distinctive shape. The lesions in both the patients and the monkeys progressed to granular hyperpigmentation by two to three weeks after photocoagulation. 相似文献