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61.
M. Bergström G. Westerberg G. Németh M. Traut G. Gross G. Greger H. Müller-Peltzer A. Safer S.-Å. Eckernäs A. Grahnér B. Långström 《European journal of clinical pharmacology》1997,52(2):121-128
Objective: The aim of the study was to investigate whether or not esuprone binds substantially to MAO-A in the human brain. Methods: In a randomised double-blind placebo-controlled study 16 male healthy volunteers were examined␣with positron emission tomography
(PET) with [11C]harmine. Eight of the volunteers were given daily doses of 800 mg esuprone, four were given bi-daily doses of 300 mg moclobemide,
and four volunteers were given placebo tablets. PET was performed before initiation of a 7-day treatment period. On day 7,
one investigation was made immediately before administration of the drug, representing 23 h after the previous day's treatment
for esuprone and 11 h after the last tablets of moclobemide. Further investigations were made 4 h and 8 h after the morning
dose on day 7. Results: PET showed a high degree of binding of [11C]harmine, a high-affinity ligand for MAO-A, before the start of treatment, and a marked and similar reduction after treatment
with esuprone and moclobemide. A slight tendency for normalisation of enzyme binding was observed at the last time point.
In the placebo group no change was observed. Plasma kinetics of esuprone showed a rapid elimination with a half-life of about
4 h. Conclusion: The study demonstrates that esuprone was comparable to moclobemide in its effect on MAO-A inhibition in the brain at the
doses given. This is an illustration of the potential of PET to monitor drug effects directly on target biochemical systems
in the brain in human volunteers, and the possibility of using these data, rather than pharmacokinetic data, for the determination
of dosing intervals.
Received: 21 August 1996 / Accepted in revised form: 22 November 1996 相似文献
62.
Jim-Shoung Lai T.-N. Wu Saou-Hsing Liou Chen-Yang Shen Chiam-Fang Guu Kquei-Nu Ko Chi. Hsueh-Yun P.-Y. Chang 《International archives of occupational and environmental health》1997,69(4):295-300
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship
between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were
measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics
and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear
regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol
consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although
PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based
on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient
lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood
lead levels in lead battery factories.
Received: 28 May 1996/Accepted: 30 August 1996 相似文献
63.
Human bladder cancer cell lines, J82, Yen-87, Shen-87 and Zoa-88, and murine bladder cancer cell lines, MBT-2 and M1660, were used as target cells for dye-sensitized photoinactivation study in using methylene blue. Normal fibroblast cells, FB-1 and FB8490, were used as control group. The cytoplasmic activity of lactic dehydrogenase, soft agar clonogenic assay, and in vivo tumor growth, survival rate and tumor taking rate with or without photoinactivation were monitored and compared between different cell lines. Efficacy of photoinactivation was time-related and more than 90 per cent of cytotoxicity could be obtained within 60 minutes of illumination. The plateau of cytotoxicity curve could be achieved after staining for 30 minutes by methylene blue under the same illumination time. Normal fibroblasts had the same features with cancer cells. Photoinactivation of tumor cells showed significant inhibition of tumor growth and tumor taking rate in experimental animals. Survival rate was also significantly prolonged in the animals with tumor cells receiving photoinactivation. These results suggest that methylene blue-sensitized photoinactivation may be useful as an adjuvant photochemotherapy for superficial bladder cancer. 相似文献
64.
Certain features of head-injured patients admitted to the Chang Gung Memorial Hospital in Taiwan during the period 1977 to 1987 were reviewed. The most common causes of injury were motorcycle accidents (56.3%) and street accidents with pedestrian injury (29.47%). The age groups with the greatest incidence of injury were aged 16-20 years, 21-25 years, and 25-30 years. The pedestrian group involving the highest incidence of injury was less than 10 years of age. Overall mortality was 17.26%. The injured pedestrian group had the highest mortality (19.1%). Initial clinical assessment was recorded using the Glasgow Coma Scale. Head-injured patients with a GCS less than 8 had a mortality in the injured pedestrian group of 46%, whereas the mortality rate in the motorcycle accident group was 41%. Additional features studied were time of occurrence of injury and pattern of injury. Information gathered from this study would suggest the need to establish a Head Injury Prevention Program in Taiwan. This of course implies major cooperation among the providers of health care delivery, the medical profession, legislators, and the government at all levels. 相似文献
65.
We report an unusual case of primary cutaneous embryonal rhabdomyosarcoma presenting as a solitary skin lesion on the anterior chest of a 20-month-old child. The tumor was characterized by small, round to oval, poorly differentiated cells. Immunohistochemically, the tumor was negative for NSE, S-100 protein, LCA, and keratin but positive for muscle-specific actin, myoglobin, desmin, and vimentin, thus indicating the presence of myogenous differentiation. Ultrastructural analysis demonstrated thick and thin filaments. Special studies showed no evidence of a primary rhabdomyosarcoma in the patient at a more typical location, nor was there any evidence of metastases. 相似文献
66.
Repeat hepatic resections for colorectal metastases 总被引:4,自引:0,他引:4
We identified 106 patients who had undergone complete resection of isolated colorectal hepatic metastases. Nine of these patients subsequently underwent repeat liver resections for isolated hepatic recurrences. The median follow-up for these patients was 21 months. One postoperative death was related to the second hepatectomy. At the time of last follow-up, five patients were alive and free of recurrent disease at 9, 19, 31, 50, and 67 months after their second hepatic resection. The remaining three patients were alive, but disease had recurred 11 months after resection in the first patient, 12 months after resection in the second, and 18 months after resection in the third. Among these three patients, two had solitary pulmonary nodules, which were resected, and one had unresectable liver disease. Our experience and a review of the literature suggest that repeat hepatic resection for isolated colorectal metastases can result in long-term survival in selected patients. 相似文献
67.
Preliminary studies of RAS mutational activation in human testicular germ cell neoplasms have yielded conflicting results. Whereas two studies of clinical material revealed a significant incidence of N- and KRAS mutations, two studies of a variety of germ cell lines failed to document RAS mutations. To clarify the incidence of RAS mutations in these tumors, we studied archival paraffin-embedded, formalin-fixed orchiectomy specimens from 25 nonseminomas (NSGCT), 18 seminomas (SEM), and one Leydig cell tumor. For 14 of the 44 neoplasms, DNA was also available from nonmalignant testis adjacent to the tumor. Six age-matched patients had testes removed because of nonmalignant disease and were studied as controls. Polymerase chain reaction (PCR) amplified the K-, N-, and HRAS 12, 13, and 61 codons of these specimens, and mutations were detected with mutation-specific oligonucleotide probe hybridization of Southern and slot blots. Four mutations were found in KRAS 12 (4/44;[9.1%]). One seminoma [1/18(5.6%)] contained the mutation GGT(GLY)----CGT(ARG), and three NSGCT [3/25(12%)] were found to have GGT(GLY)----GAT(ASP) mutations. One of the NSGCT mutations was detected in adjacent nonmalignant tissue, but the corresponding tumor did not contain any detectable mutation. No mutations were detected at KRAS 13 or 61, in NRAS or HRAS 12, 13, or 61, or in the control normal testes. PCR, slot blots, and hybridizations were performed twice by two separate investigators for confirmation of results. PCR-generated mutation-specific positive controls were created for all possible RAS mutations, and these along with wild-type DNA controls were integral to interpretation of the oligonucleotide mismatch hybridization assay. By using positive and negative controls, we have detected a relatively low incidence of RAS mutations in archival human testicular germ cell tumors. 相似文献
68.
根据公认的眼科解剖学数据,提出后房型人工晶体植入屈光度的术前预测方法:IOL(D)=1.02(+21D+2X)。经人工晶体专用眼科A超36眼实测对比,无显著差异,认为在地市级医院和县级医院后房型人工晶体植入术推广中具有积极意义。 相似文献
69.
报告14例后房型人工晶体植入术后继发青光眼患者,男性8例,女性6例。均为单眼发病,其中10例发生在术后1个月以内,另4例发生在1~3年以后。其中开角型8例,闭用型6例。7例经抗青光眼药物治疗可控制眼压,4例用激光治疗,另3例需行抗青光眼手术。治疗前矫正视力达0.5以上者为28%,治疗后矫止视力达0.5以上增加至50%。所有病例均眼压控制良好、视力不良原因为青光眼世视神经萎缩,提示早期发现的重要性。 相似文献
70.