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61.
The aim of this study was to assess the bioequivalence of H13CO-3 and H14CO-3, by administering both labels simultaneously by single infusion and comparing their recovery in breath CO2 and urinary urea. Six healthy male subjects (age range 24-41 years; weight 76.7 (sd, 18.6) kg; height 1.79 (sd 0.05) m) were infused with unprimed solutions of HCO3- (110.0 mmol/kg) labelled with 13C (0.76 mmol 13C/h) and 14C (48 Bq/h) at a constant rate for 6 h, in a whole-body calorimeter (1400 litres) for measurement of CO2 production. Samples of breath were collected hourly in a Douglas bag and all urine was collected into two batches (0-4 h and 4-6 h) for estimating recovery of infused label by measurement of enrichment or specific activity. Recovery in breath CO2 of both labels increased from about 25 % for the first hour to 88 % and above for hours 3-4 onwards. Mean recovery of 13C in breath CO2 was slightly higher than that of 14C for all periods (mean difference always less than 1 % of infused label) but was significant only for the first 3 h (P < 0.05). Recovery of 14C in urea was significantly higher (P < 0.01) than 13C, but was confounded by substantial variability and uncertainties concerning 13CO2 background enrichments. These results suggest that there is no compelling need to alter factors currently used for recovery of 14C in breath when using 13C instead, and vice versa.  相似文献   
62.
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic hydrocarbon, is the most potent carcinogen ever tested in mouse skin and rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction, tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in strain A/J mouse lung. Groups of mice received a single i.p. injection of 0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment, DNA adducts were measured at times between 1 and 28 days, while tumors were counted at 250 days and analyzed for the occurrence of point mutations in codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung induced six major and four minor DNA adducts. Maximal levels of adduction occurred between 5 and 10 days after injection followed by a gradual decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti- and syn-11,12- dihydroxy-13,14-epoxy- 11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed by cochromatography. The major adduct was identified as a product of the reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced significant numbers of lung adenomas in a dose- dependent manner, with the highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based on the administered dose, DB[a,l]P was more active than other environmental carcinogens including benzo[a]pyrene. As a function of time-integrated DNA adduct levels, DB[a,l]P induced lung adenomas with about the same potency as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar in carcinogenic potency to other PAHs in the strain A/J mouse lung model. Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors revealed the predominant mutations to be G-->T transversions in the first base of codon 12, A-->G transitions in the second base of codon 12, and A-->T transversions in the second or third base of codon 61, concordant with the DNA adduct profile.   相似文献   
63.
Ruan  Sanbao  Fuller  Greg  Levin  Victor  Bruner  Janet M.  Zhang  Wei 《Journal of neuro-oncology》1998,37(3):223-228
The p21WAF1/Cip1 (p21) protein, a negative regulator of G1 checkpoint control, was overexpressed in the majority of human gliomas. To investigate whether p21 expression in brain metastases from various systemic origins is similar to that in gliomas and whether p21 expression is regulated differently in brain metastases and in corresponding primary tumors, we used immunohistochemical staining to examine the expression of p21 in paraffin-embedded sections prepared from primary colon and breast carcinomas and from metastatic brain tumors that originated from colon, breast, lung, and kidney cancers and from melanoma. Our results showed that 56% (28 of 50) of the brain metastases samples have more than 1% p21-positive staining cells compared with 87% of primary gliomas reported previously. Among the samples analyzed, p21 expression in brain metastases from breast carcinomas was much higher than in primary breast carcinomas. In contrast, p21 expression in brain metastases from colon carcinomas was less than primary colon carcinomas. The results from this pilot study suggest that p21 expression is regulated differently in metastatic and primary tumors.  相似文献   
64.
Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis  相似文献   
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67.
INTRODUCTION BY THE COLUMN EDITORS: Because the mental health system in Japan has emphasized hospital-based treatment (1), patients with schizophrenia often remain institutionalized for long periods, even after their symptoms have stabilized. In addition, the introduction of modern community-based methods of treatment and rehabilitation was delayed by an antipsychiatry movement in the 1970s and the ascendance of a reductionistic biological approach to services (2). Lack of adequate outpatient services and community residential care in Japan has been a serious obstacle to destigmatization of mental disorders and has contributed to the heavy burden and stress experienced by families of mentally ill persons (3). More than 80 percent of patients discharged from mental hospitals return to live with their families, who are ill prepared to provide the supportive services required for community tenure.Involvement in work activities can facilitate community reentry for people with serious and persistent mental illness because employment displaces symptoms, provides structure and meaning in daily life, offers socialization with peers, and permits workers to earn income for shelter and food. In this issue's Rehab Rounds column, the authors describe an innovative vocational rehabilitation program for patients with schizophrenia that was designed to overcome obstacles to discharge and community adjustment. The program at Yabuki Prefecture Psychiatric Hospital, in the northern prefecture of Fukushima, Japan, has been successful in training patients for competitive work while capitalizing on the importance of work in Japanese culture and its traditionally supportive employer-employee relationships. The program is termed "hybrid" because it combines elements of transitional employment with supported employment (4).  相似文献   
68.
This study was carried out to define the post-treatment appearance of the chest radiographs in 44 consecutive patients with Hodgkin disease who received mantle irradiation with or without chemotherapy and to determine how the incidence and severity of post-treatment abnormalities relate to the radiation parameters and chemotherapeutic regimens. Radiographs of the chest in 44 patients, computed tomograms of the chest in 31 patients and of the abdomen of 35 patients were reviewed, prior to and following treatment, for mediastinal contours, pericardial status, cardiac size and pulmonary fibrosis. All patients were followed for a minimum of 1 year and 27 were followed for more than 5 years. Stable post-treatment imaging studies were correlated with the initial extent of disease, radiation parameters, and chemotherapeutic regimens. Stable post-treatment findings were categorised as follows: the chest radiograph was normal or showed subtle vascular reorientation; moderate paramediastinal fibrosis was present; severe pulmonary fibrosis had occurred with narrowing of the cardiomediastinal silhouette in some patients. In general, the severity of the fibrosis was dependent on (1) the size of the radiation fields and on whether or not the coverage of the hila included a 1- to 2-cm margin; (2) the amounts of chemotherapy and particularly bleomycin containing regimens and (3) individual susceptibility of normal tissue irradiation. Therapy for Hodgkin disease is not necessarily associated with radiographic sequelae regardless of the initial status of the mediastinum or the treatment. However, the post-treatment appearance of the chest radiographs in this study was related strongly to (1) the initial extent of disease and particularly the status of the hila, both of which influenced the amounts of lung parenchyma that were included in the treatment fields; (2) the use of bleomycin in chemotherapy regimens and (3) individual normal tissue radiosensitivity.  相似文献   
69.
PURPOSE: To describe clinical features, therapeutic approaches, and prognostic factors in pediatric patients with atypical teratoid/rhabdoid tumors (ATRT) treated at St Jude Children's Research Hospital (SJCRH). PATIENTS AND METHODS: Primary tumor samples from patients diagnosed with ATRT at SJCRH between July 1984 and June 2003 were identified. Pathology review included histologic, immunohistochemical analysis, and fluorescence in situ hybridization for SMARCB1 (also known as hSNF5/INI1) deletion. Clinical records of patients with pathologic confirmation of ATRT were reviewed. RESULTS: Thirty-seven patients were diagnosed with ATRT at SJCRH during the 19-year study interval. Six patients were excluded from this clinical review based on pathologic or clinical criteria. Of the remaining 31 patients, 22 were younger than 3 years. Posterior fossa primary lesions and metastatic disease at diagnosis were more common in younger patients with ATRT. All patients underwent surgical resection; 30 received subsequent chemotherapy. The majority of patients aged 3 years or older received postoperative craniospinal radiation. Two-year event-free (EFS) and overall survival (OS) of children aged 3 years or older (EFS, 78% + 14%; OS, 89% +/- 11%) were significantly better than those for younger patients (EFS, 11% +/- 6%; OS, 17% +/- 8%); EFS, P = .009 and OS, P = .0001. No other clinical characteristics were predictive of survival. Three of four patients 3 years or older with progressive disease were successfully rescued with ifosfamide, carboplatin, and etoposide therapy. CONCLUSION: Children presenting with ATRT before the age of 3 years have a dismal prognosis. ATRT presenting in older patients can be cured using a combination of radiation and high-dose alkylating therapy. Older patients with relapsed ATRT can have salvage treatment using ICE chemotherapy.  相似文献   
70.
Curability of solitary bone plasmacytoma.   总被引:4,自引:0,他引:4  
PURPOSE: The effects of involved-field radiotherapy were assessed in patients with a solitary plasmacytoma of bone (SBP). PATIENTS AND METHODS: Forty-five consecutive patients with an SBP received megavoltage irradiation of at least 3,000 cGy. The median age was 53 years, 67% of patients showed a myeloma protein, and uninvolved immunoglobulins (Igs) were preserved in 93% of patients. RESULTS: Permanent control of presenting disease was achieved in all but two patients, but 46% of patients developed multiple myeloma. When it occurred, progression of myeloma occurred within 3 years in two thirds of the patients, suggesting that the extent of disease was understaged at diagnosis. Myeloma protein disappeared in nine patients (30%) whose disease has not yet recurred. The median survival for all patients was 13 years and the myeloma-specific survival fraction at 10 years was 53%. CONCLUSION: In patients with an SBP, the disappearance of myeloma protein with involved-field radiotherapy predicted long-term disease-free survival and possible cure. Nonsecretory disease and persistent myeloma protein after treatment were adverse prognostic factors for which adjuvant therapy with interferon alfa should be considered.  相似文献   
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