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21.
We have previously shown that eating disorders are a compulsive behaviour disease, characterized by frequent recall of anorexic thoughts. Evidence suggests that memory is a neocortical neuronal network, excitation of which involves the hippocampus, with recall occurring by re-excitement of the same specific network. Excitement of the hippocampus by glutamate-NMDA receptors, leading to long-term potentiation (LTP), can be blocked by ketamine. Continuous block of LTP prevents new memory formation but does not affect previous memories. Opioid antagonists prevent loss of consciousness with ketamine but do not prevent the block of LTP. We used infusions of 20 mg per hour ketamine for 10 h with 20 mg twice daily nalmefene as opioid antagonist to treat 15 patients with a long history of eating disorder, all of whom were chronic and resistant to several other forms of treatment. Nine (responders) showed prolonged remission when treated with two to nine ketamine infusions at intervals of 5 days to 3 weeks. Clinical response was associated with a significant decrease in Compulsion score: before ketamine, mean +/- SE was 44.0 +/- 2.5; after ketamine, 27.0 +/- 3.5 (t test, p = 0.0016). In six patients (non-responders) the score was: before ketamine, 42.8 +/- 3.7; after ketamine, 44.8 +/- 3.1. There was no significant response to at least five ketamine treatments, perhaps because the compulsive drive was re-established too soon after the infusion, or because the dose of opioid antagonist, nalmefene, was too low. 相似文献
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PURPOSE: Surgery and systemic chemotherapy offer modest benefit to patients with recurrent glioblastoma multiforme. These tumors are associated with rapid growth and progressive neurological deterioration. Radiosurgery offers a rational alternative treatment, delivering intensive local therapy. A pilot protocol to treat recurrent glioblastoma was developed using fractionated stereotactic radiosurgery with concurrent intravenous (i.v.) Taxol as a radiation sensitizer. METHODS AND MATERIALS: The treatment outcome was analyzed in 14 patients with recurrent glioblastoma treated with fractionated stereotactic radiosurgery and concurrent Taxol. Median tumor volume was 15.7 cc and patients received a mean radiation dose of 6.2 Gy at 90% isodose line, 4 times weekly. The median dose of Taxol was 120 mg/m2. RESULTS: The median survival was 14.2 months, 1-year survival was 50%. CONCLUSIONS: Survival for this small group of patients was similar to or better than historical controls or patients treated with single-fraction radiosurgery alone. This data should stimulate the investigation of both fractionated radiosurgery and the development of radiation sensitizers to further enhance treatment. 相似文献
24.
A consecutive series of 49 elderly patients of mean age 73 years with full-thickness rectal prolapse underwent the Delorme operation between 1986 and 1990. A standard technique was used, or supervised, by one surgeon. In this prospective series, 43 patients were reviewed clinically. The Delorme operation abolished rectal prolapse in 32 patients. Half of the 40 with faecal incontinence were rendered continent. Failure was related to previous anorectal surgery and/or psychiatric illness. Of the 11 patients in whom the first procedure failed, four were improved by a second Delorme operation. The Delorme operation is a suitable procedure for elderly and/or medically unfit patients with rectal prolapse. Good results have also been demonstrated for younger patients, suggesting that the operation may have wider application. 相似文献
25.
YJ Lidor WE Lee JH Nilson IH Maxwell LJ Su E Brand LM Glode 《Canadian Metallurgical Quarterly》1997,177(3):579-585
OBJECTIVE: Our goal was to determine whether toxicity of the diphtheria toxin A-chain gene regulated by the human chorionic gonadotropin promoter can be directed to malignant ovarian cell lines. STUDY DESIGN: Plasmids containing diphtheria toxin A-chain gene linked to the regulatory elements of the metalloergothioneine and human chorionic gonadotropin promoters were transfected into the cell lines. Expression of diphtheria toxin A-chain gene was determined by the inhibition of a cotransfected luciferase reporter gene. RESULTS: Cytotoxicity of the diphtheria toxin A-chain gene is shown in a dose-responsive manner. Transfection of a plasmid expressing the diphtheria toxin A-chain gene controlled by a constitutive promoter readily inhibits protein synthesis. Specific inhibition of luciferase protein synthesis occurs in ovarian cancer cells transfected with the diphtheria toxin A-chain gene under the control of the human chorionic gonadotropin promoters when compared with normal ovarian epithelial cells or fibroblasts. CONCLUSIONS: These data demonstrate the preferential expression of the diphtheria toxin A-chain gene, regulated by the human chorionic gonadotropin promoter, to ovarian cancer cell lines. This provides an avenue for targeting such cells for suicide, toxin, or cytokine genes. 相似文献
26.
IH Skrypal' 《Canadian Metallurgical Quarterly》1997,59(6):63-74
The state and prospects of research on creation of antiadhesins--new generation drugs for preventing and treatment of infectious diseases, are analyzed in the paper. The elaboration of such drugs is based on the profound knowledge about the nature of viral, bacterial, fungal and other infectious agents of diseases, molecular mechanisms of their interactions with the affected organs and tissues which are based on the processes of carbohydrate-protein recognizing. Rapid development of such fields of science as glycobiology and lectinology has created the preconditions for artificial synthesis of oligosaccharides which mimicked the receptors and can interact with adhesive structures of the disease agents more intensively than their natural analogs and block them. This makes the interaction of the latter with the affected organs impossible. The intensive work on elaboration of natural drugs: antiadhesins, is carried out in most countries. Adhesins are not harmful for people and cannot provoke the development of resistance to them in the disease agents. Till recently Ukraine belonged to the number of countries where the fields of science mentioned above were intensively developed but, in connection with the present stagnation of science and even the artificial hindering of its development, the country gradually losses the position of a leader. Hence, one can conclude that when 10-15 years later the market of pharmaceutical products will be filled with antiadhesins, our country will not be on the list of their producers, if the authorities will spend funds to buy foreign drugs as before instead of stimulating the development and production of the home ones. 相似文献
27.
CL Vandewalle MI Coeckelberghs IH De Leeuw MV Du Caju FC Schuit DG Pipeleers FK Gorus 《Canadian Metallurgical Quarterly》1997,20(10):1556-1561
OBJECTIVE: To compare the incidence rate of IDDM in the age-groups 0-14 and 15-39 years in Antwerp, Belgium, and to compare demographic, clinical, and biological data from Antwerp IDDM patients with 92% ascertainment with those from a larger Belgian patient group with 40% ascertainment. RESEARCH DESIGN AND METHODS: Incident cases of IDDM were reported by physicians of the Belgian Diabetes Registry and in Antwerp by several other sources. In Antwerp, completeness of ascertainment was calculated by the capture-recapture method. Demographic and clinical data were collected by questionnaire. Blood was sampled for HLA-DQ genotyping and, in new-inset patients, for autoantibodies. RESULTS: In Antwerp, the age- and sex-standardized IDDM incidence rates were similar in both age-groups (0-14 years: 11.8/100,000; 15-39 years: 8.9/100,000). The incidence rate decreased in girls above age 15 years (6.9/100,000; P = 0.003) but not in boys (11.0/100,000). Both in Antwerp and Belgium, IDDM was diagnosed more frequently in the 15-39 years age-group (60% of all cases) than under age 15 years, with a lower prevalence of acute symptoms, ketonuria, high-risk HLA-DQ genotype, and autoantibodies against insulin, islet cells, and IA-2, but with a higher prevalence of GAD65 autoantibodies. CONCLUSIONS: In Antwerp, the incidence rate of IDDM under age 15 years is intermediately high compared with the rates in other European regions. It is similar in the 15-39 years age-group, but with a marked male predominance. Demographic, clinical, and biological data show the same age-dependent heterogeneity as the data collected nationwide, with 40% ascertainment indicating the representativeness of the latter. 相似文献
28.
Energy transfer in LHCII monomers at 77K studied by sub-picosecond transient absorption spectroscopy
FJ Kleima CC Gradinaru F Calkoen IH van Stokkum R van Grondelle H van Amerongen 《Canadian Metallurgical Quarterly》1997,36(49):15262-15268
Energy transfer from chlorophyll b (Chl b) to chlorophyll a (Chl a) in monomeric preparations of light-harvesting complex II (LHCII) from spinach was studied at 77 K using pump-probe experiments. Sub-picosecond excitation pulses centered at 650 nm were used to excite preferentially Chl b and difference absorption spectra were detected from 630 to 700 nm. Two distinct Chl b to Chl a transfer times, approximately 200 fs and 3 ps, were found. A clearly distinguishable energy transfer process between Chl a molecules occurred with a time constant of 18 ps. The LHCII monomer data are compared to previously obtained LHCII trimer data, and both data sets are fitted simultaneously using a global analysis fitting routine. Both sets could be described with the following time constants: 140 fs, 600 fs, 8 ps, 20 ps, and 2.9 ns. In both monomers and trimers 50% of the Chl b to Chl a transfer is ultrafast (<200 fs). However, for monomers this transfer occurs to Chl a molecules that absorb significantly more toward shorter wavelengths than for trimers. Part of the transfer from Chl b to Chl a that occurs with a time constant of 600 fs in trimers is slowed down to several picoseconds in monomers. However, it is argued that observed differences between monomers and trimers should be ascribed to the loss of some Chl a upon monomerization or a shift of the absorption maximum of one or several Chl a molecules. It is concluded that Chl b to Chl a transfer occurs only within monomeric subunits of the trimers and not between different subunits. 相似文献
29.
To explore the role of psychosocial factors in the development and persistence of idiopathic musculoskeletal pain (IMP) in children, 23 children with IMP and 52 children with juvenile chronic arthritis (JCA) were compared at first admission to hospital and at 9 y follow-up. Semistructured interviews were performed at both assessments. At first admission, the prevalence of psychiatric diagnoses was high both in patients with IMP and patients with JCA, but patients with IMP more often had pain models, reported more school stress and more often lived with one biological parent. At follow-up, overall psychosocial functioning and level of chronic family difficulties were improved in both groups, but patients with IMP had a higher prevalence of psychiatric diagnoses and more chronic family difficulties and life events than patients with JCA. The persistence of IMP at follow-up was related to pain models, school stress, less parental education and more chronic family difficulties at first admission. Findings support the association between psychosocial factors and childhood IMP. 相似文献
30.
PD Forsyth EM Bessell AJ Moloney IH Leach JM Davies J Fletcher 《Canadian Metallurgical Quarterly》1997,33(10):1638-1642
Between 1973 and 1993, 529 patients aged 15 years and over with Hodgkin's disease (HD) were entered into a lymphoma registry. Twenty-eight cases (1 only diagnosed at autopsy) of histologically proven HD in patients aged 70 years or older were identified. The distribution of sex, 'B' symptoms, histology and stage was not significantly different from that of younger patients, except for the fact that there were no patients aged 70 years or older with lymphocyte predominant HD. Nineteen patients were treated radically, 5 patients palliatively and 4 patients received no radiotherapy or chemotherapy. Three of the 14 patients treated with chemotherapy achieved the planned dose intensity. The cause-specific 5-year survival was 75% for patients aged 15-69 years and 28% for patients aged 70 years and over (logrank chi(2) = 43.7, P < 0.00001). The younger and older groups treated with radical intent had complete response rates of 97% and 74%, respectively (logrank chi(2) = 17.91, P < 0.00001) and relapse rates at 5 years of 27% and 56%, respectively (logrank chi(2) = 4.86, P = 0.0275). The main reason for the poorer prognosis of patients aged 70 years and over was the increasing difficulty of chemotherapy delivery associated with advancing age. 相似文献