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81.
We compared the cytotoxic effects of two anthracycline derivatives, epirubicin (EPI) and adriamycin (ADM), against human tumor cells in vitro. Various tumor specimens, obtained at surgery, included 57 liver, 19 lung, 16 gastric, 10 colorectal and 7 breast cancer specimens. These tumor cells were exposed to the same concentration of EPI or ADM for 3 days. The chemosensitivity of each tumor cell type to each drug was then assayed using the in vitro succinate dehydrogenase inhibition (SDI) test. Sensitivity to the treatment was defined as a 50% or greater reduction in the succinate dehydrogenase (SD) activity of the tumor cells, relative to that of the control (untreated) cells. Each cell type, except for gastric cancer cells, was equally sensitive to EPI and ADM. Gastric cancer cells were more sensitive to EPI than to ADM (P less than 0.05). The rate of coincidence, the sum of the co-sensitive and co-resistant rates of all the tumors, was quite high (90.8%). Thus, these findings indicate that EPI and ADM are equally cytotoxic to each tumor cell type, but EPI is more cytotoxic than ADM to gastric cancer cells. Since EPI is reported to be less cardiotoxic than ADM, EPI may replace ADM in cancer chemotherapy.  相似文献   
82.
The modulating effects of caffeine, nicotine, ethanol and sodium selenite on development of N-nitrosobis(2-oxopropyl)-amine (BOP)-initiated pancreatic tumors were investigated. Female Syrian golden hamsters were given s.c. injections of BOP (10 mg/kg body weight) or saline alone once a week for 3 weeks and then administered 2000 p.p.m. caffeine, 25 p.p.m. nicotine, 20% ethanol or 4 p.p.m. sodium selenite in their drinking water for the next 37 weeks. Control animals were given tap water alone after BOP initiation. Only the BOP-treated groups developed pancreatic adenocarcinomas and dysplasias. The multiplicity of pancreatic carcinomas was significantly higher (P less than 0.05) in animals receiving caffeine than in the controls. In addition, caffeine treatment slightly increased the incidence of carcinomas. Nicotine and ethanol also showed tendencies to enhance pancreatic carcinogenesis, although there were statistically no significant differences regarding lesion development. In contrast, sodium selenite administration was associated with a tendency for a decrease in the number of carcinomas and dysplasias. Thus, among these chemicals of obvious significance to human life-style, caffeine enhanced the development of pancreatic tumors when administered during the post-initiation phase in this hamster model.  相似文献   
83.
84.
Forestomach papillomas and skin papillomas were induced very efficiently by a single dose administration of the chemical carcinogen methylnitrosourea (MNU) in transgenic mice (rasH2 line) carrying human hybrid c-Ha-ras genes, which encode the prototype p21 gene product. The incidence of forestomach papillomas was dose dependent; when 50 mg/kg of MNU were administered i.p., all of the transgenic mice (56 of 56) developed forestomach papillomas within 12 weeks after administration, whereas 5 and 0.5 mg/kg of MNU induced papillomas in 2 of 19 and 1 of 19 mice, respectively. Nine of 56 transgenic mice (16%) also developed skin papillomas at sites wounded by bites or scratches. Only 1 of 77 nontransgenic littermates developed forestomach papillomas after administration of 50 mg/kg of MNU, and no skin papillomas appeared within 12 weeks after MNU administration. The transgenes (integrated copy number, 5-6) in the tumors developed in 55 of 56 affected transgenic mice (98%) contained at least 1 copy of the transgene that was activated by somatic point mutation at the 12th codon, from GGC (Gly) to GAC (Asp). Because somatic point mutations at the 12th or 61st codon of transgenes have never been detected in normal tissues of transgenic mice thus far examined, these mutational activations of transgenes are tumor-specific events. RNA expression of these activated transgenes was also detected. From these results, it is suggested that somatic mutational activation of the human c-Ha-ras transgene plays a causative role in the occurrence of forestomach and skin papillomas induced by MNU administration in these transgenic mice. This transgenic mouse provides a unique screening system for chemicals that induce or suppress papillomagenesis.  相似文献   
85.
What should general hospital psychiatry do in a community?]   总被引:1,自引:0,他引:1  
Some experiences in Nagano Red Cross hospital and Nagano Prefecture are presented, and the role of general hospital psychiatry (GHP) in a community is discussed. Psychiatric services in Nagano prefecture with population 2.21 million consist of four blocks. Our unit is in north block, providing treatment for acute phase and, in 2000, 1504 cases were new outpatients, daily outpatients were 198 cases and new inpatients were 604 cases including 146 emergency inpatients. In fiscal 2001, 25.6% of notifications of involuntary hospitalization from all psychiatric hospitals were submitted from GHP occupying 12.9% psychiatric beds, and 129 notifications from our unit were largest in Nagano prefecture. Total 7 GHPs with beds are presented by some data, suggesting two types as GHP. One type has relatively many new inpatients by small beds with short-term hospitalization like our GHP, and another type has relatively small new inpatients by large beds with long-term hospitalization like conventional mental hospital. It is necessary for GHP to pursue the former type, and to functionally differentiate from psychiatric hospital. Results of psychiatric emergency system in Nagano prefecture are presented. Designated hospitals are our GHP with 60 beds in north block, Prefectural Hospital with 310 beds in south block, National Sanatorium with 280 beds in east block and rotating 5 psychiatric hospitals with total 968 beds in west block. GHP with 60 beds hospitalized more emergency new cases than other psychiatric hospitals with large beds and discharged 84% of emergency inpatients to their home. Recently, short-term hospitalization of general hospital beds has rapidly progressed, and shared goal settings are needed, and treatment plans with teamwork by various types of experts have started from community-based home care. This teamwork will be expected throughout community psychiatric services. Although until today GHP's ward unit is financially disadvantageous, patients anticipate medical care of GHP on same level as a part of general hospital of course. For community psychiatric care and short-term hospitalization it is necessary for GHP to cooperate with various types of social resources. As for users of rehabilitation facilities in Nagano prefecture, GHP outpatients occupy 27.2%, and as for day care users, these occupy 19.6%, thus GHPs are able to cooperate with facilities. Above-mentioned facts indicate there is high necessity as a GHP, not a psychiatric hospital or a clinic. Cooperation between GHP and other social resources including welfare services will enrich community psychiatric services. GHP is a wide entrance for psychiatric care from a viewpoints of whole psychiatric care. When GHP accepted all patients on demands from acute cases to chronic, manpower will be diffused, and safety of medical care will be undermined. Therefore, psychiatric triage mainly functioning to treat early stage in severe cases with combined medical and psychiatric illness above all is necessary for GHP in order to offer proper treatment to a community. Accessibility in early stage of disease, priority of seriously ill patients and rehabilitation programs at a community as daily life space are essential for community mental health. We believe the first role of GHP in a community is to seek for psychiatric treatment on same level as general medicine. The second role is the psychiatric triage in order to function as GHP in a community. The third role is to cooperate with other social resources in a community. In order to promote the above it is necessary to self-evaluate GHP concerning the difference with specialized psychiatric hospitals or clinics. From these viewpoints GHP will become a core of community psychiatry. Currently, however, preparation concerned with GHP is poor compared with other advanced countries, so an aggressive improvement in medical policy is expected.  相似文献   
86.
Objective: This study evaluates the risks of postoperative complications in 124 patients with non-small-cell lung cancer who received pre-operative induction chemoradiotherapy and surgery. Methods: All patients with non-small-cell lung cancer who underwent surgery after induction therapy between January 1990 and December 2003 were reviewed. We adopted univariate and multiple logistic regression models to identify predictors that increased the incidence of postoperative complications. Results: Of 124 patients, 59 received carboplatin and docetaxel, 53 received cisplatin and etoposide, and 12 received other platinum-based combinations. Pre-operative thoracic radiotherapy was performed concurrently with chemotherapy. The median dose to the primary tumor was 40 Gy, and 29 patients (23.4%) received radiotherapy of more than 45 Gy before surgery. There were 25 pneumonectomies (20.2%). The overall postoperative mortality was 9 of 124 patients (7.3%), and complications developed in 54 patients (43.5%). Multivariate analysis demonstrated that only thoracic radiotherapy of more than 45 Gy predicted postoperative complications (P = 0.021; odds ratio, 3.620; 95% confidence interval, 1.214–10.797). Conclusions: Thoracic radiotherapy of more than 45 Gy, in combination with chemotherapy, was a significant risk factor for postoperative complications.  相似文献   
87.
In order to examine the mechanism by which the oral carbonaceousadsorbent, AST-120 delays the appearance of glomerular sclerosis,experiments were carried out in 120 male Sprague-Dawley ratsweighing 285–320 g. The rats were first subjected to 2/3,3/4, and 4/5 nephrectomy (n=40). The experiments were begunat 2 weeks after the surgery, and were performed over an 8-weekperiod. Half of each group (n=20) was administered 1 g/day ofliquid AST-120, and the other half received liquid vehicle solutionwith pair feeding in each group. In the 2/3 nephrectomized groupthe administration of AST-120 delayed the occurrence of glomerularhypertrophy and prevented the appearance of glomerular sclerosiswithout any significant differences in renal function, systemicblood pressure (SBP), and urinary protein excretion (U-P). Inthe 3/4 nephrectomized group the administration of AST-120 delayedthe appearance of glomerular hypertrophy and sclerosis withsignificant decreases in SBP and U-P. In the 4/5 nephrectomizedgroup the administration of AST-120 delayed the appearance ofglomerular sclerosis and prevented a decrease in renal function.It is concluded that administration of the oral adsorbent AST-120delays the occurrence of glomerular sclerosis by delaying theappearance of glomerular hypertrophy, systemic hypertension,and the increase in proteinuria. It can be therefore mentionedthat the accumulating substances in the digestive tract worsenthe abnormal milieu of chronic renal failure.  相似文献   
88.
Pepsinogens are acid protease enzymes of pepsin usually found in gastric mucosa. In the present study, we demonstrated the presence of pepsinogen isozymes in male Syrian golden hamster lung tissues by a combined immunohistochemical and biochemical approach. Immunohistochemically, using rat pepsinogen 1 antibody, pepsinogen positive cells were observed mainly in the epithelia of the terminal bronchioles. They demonstrated morphological features of Clara cells. The pepsinogen isozyme pattern of lung tissue determined by polyacrylamide gel electrophoresis was similar to that of stomach mucosa. Treatment of hamsters with polychlorinated biphenyls at a dose of 500 mg/kg body weight ip caused a 2.8-fold increase in pepsinogen content (p less than 0.01) as well as increase in numbers of pepsinogen positive cells in the lung.  相似文献   
89.
90.
We have previously reported that KU-2285, a 2-nitroimidazole with a fluorinated N1-substituent (-CH2-CF2CONH(CH2)nOH, n = 2), was a promising hypoxic cell radiosensitizer. In this study the pharmacokinetics of KU-2285 and its related compounds (n = 3 and n = 4) were compared with those of etanidazole (a 2-nitroimidazole with an N1-substituent of -CH2CONH(CH2)nOH, n = 2) and its related compounds (n = 3 and n = 4) to assess the effects of incorporation of a CF2 group. The lipophilicity of the fluorinated compounds was higher than that of etanidazole, as measured by the octanol/water partition coefficient. As the number of CH2 groups increased, the lipophilicity of the compounds in both the KU-2285 and etanidazole series increased. The brain tissue levels of the fluorinated compounds were as low as those of the etanidazole derivatives, while the biological half-lives of the fluorinated compounds in peripheral nervous tissues were shorter than those of related non-fluorinated compounds.  相似文献   
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