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71.
A 57-year-old female presented with an abnormal Pap smear. Colposcopic examination of the cervix revealed white mucosa with erosion and several areas of black pigmentation. After a colposcopically directed biopsy and loop conization, radical hysterectomy and bilateral salpingo-oophorectomy with pelvic and paraaortic lymphadenectomy were performed. Pathological examination disclosed an invasive squamous cell carcinoma admixed with many dendritic melanocytes. Melanin granules were present within the melanocytes and tumor cells. Although similar tumors have been reported in other sites, this is the first report to our knowledge of a pigmented squamous cell carcinoma of the uterine cervix.  相似文献   
72.
We describe a case of a large bronchial fistula and empyema after right upper lobectomy that was treated successfully with open window thoracostomy followed by a latissimus dorsi myocutaneous flap and limited thoracoplasty. A latissimus dorsi myocutaneous flap can provide immediate airtight closure of a large bronchial fistula, allowing lavage and curettage of the empyema cavity to reduce the chance of postoperative infection. An important aspect of this technique is that the deepithelialized skin side rather than muscle is sutured to an opening of the bronchus. As compared with other techniques, a latissimus dorsi myocutaneous flap is superior in that it requires a single incision and does not require an intraop-erative change of position. In addition, the technique causes little dysfunction of the chest and shoulder and preserves the vascular supply to ensure the viability of the flap even if it was divided in a previous operation.  相似文献   
73.
74.
The p53 gene has been implicated as a tumor suppressor gene involved in the pathogenesis of lung cancer. Our previous study revealed that the p53 gene is frequently mutated with a distinct nucleotide substitution pattern in small cell lung cancer specimens in Japanese patients. In this study, we examined 30 primary, resected non-small cell lung cancer samples in Japanese patients using complementary DNA-polymerase chain reaction and sequencing. Mutations changing the p53 coding sequence were found in 14 of 30 tumor samples (47%), while G:C to T:A transversions which are uncommon in other cancers such as colon cancer were the most frequently observed mutations, in agreement with an earlier report on non-small cell lung cancer in American patients. Furthermore, the present study shows for the first time that in univariate and multivariate analyses, the presence of p53 mutations is closely associated with lifetime cigarette consumption.  相似文献   
75.
The effects of calcium chloride on glandular stomach carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and sodium chloride were investigated in male outbred Wistar rats. Animals were given MNNG solution (100 p.p.m.) as drinking water and simultaneously fed a diet supplemented with 5% sodium chloride for 8 weeks. Matched negative controls received neither MNNG nor sodium chloride. Rats were then fed basal diet and given calcium chloride solution (1 or 0.2%) or tap water for the following 52 weeks. The incidences and multiplicities of preneoplastic hyperplasias in the glandular stomachs of rats given MNNG/sodium chloride followed by 1 and 0.2% calcium chloride were significantly lower than those in rats given MNNG/sodium chloride alone. The inhibitory effects of calcium were exerted in a dose-dependent manner. Calcium treatment also showed a tendency to inhibit the development of gastric adenocarcinomas although this was not statistically significant. Rats without carcinogen treatment had neither carcinomas nor preneoplastic hyperplasias in the glandular stomach. Calcium intake also significantly reduced the levels of malondialdehyde, a measure of lipid peroxidation, in the gastric mucosa and urine, the former in a dose-dependent manner. Thus, calcium chloride exerted inhibitory effects when given during the post-initiation phase of two-stage glandular stomach carcinogenesis in rats.  相似文献   
76.
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   
77.
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   
78.
79.
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   
80.
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   
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