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991.
Aromatase inhibitor shows efficacy for hormone receptor positive postmenopausal breast cancer. We evaluated the activity of 24 weeks of aromatase inhibition with exemestane for primary breast cancer in a neoadjuvant setting. Patients with stage II/IIIA invasive breast cancer with estrogen receptor (ER) and/or progesterone receptor (PgR)-positive status were eligible. Primary endpoints were objective response rate (ORR) and safety. A steroidal aromatase inhibitor exemestane of 25 mg/day was administered for 16 weeks with an 8-week extension. Secondary endpoints were rates of breast-conserving surgery (BCS), and change of Ki67 index and ER/PgR expression in central laboratory analyses. Between March 2006 and December 2007, 116 patients were enrolled. Among those, 102 patients completed 24 weeks of administration. The ORR was 47% (55/116) at Week 16 and 51% (59/116) at Week 24, respectively. No serious toxicity was seen. ORR was associated with ER Allred scores but not with PgR scores. The significant reduction in Ki67 index was confirmed. No progression was experienced in tumors with less than 15% Ki67 index. Pathological response was observed in 28 (30%) of 94 evaluated cases. No statistical correlation between pre-treatment Ki67 index and pathological response was detected; however, a trend of correlation was found between the post-treatment preoperative endocrine prognostic index (PEPI), a prognostic score and the pathological response. At diagnosis, 59 patients (51%) would have required mastectomy but 40 patients were converted to BCS, showing an increase in the rate of BCS (77%). The 24-week aromatase inhibition provided preferable clinical benefits with significant reduction in Ki67 index. More precise mechanisms of the response need to be investigated.  相似文献   
992.
The potential genotoxicity of the rodent liver carcinogen 2,6-dinitrotoluene (2,6-DNT) was evaluated in compliance with the guidelines for genotoxicity studies of drugs (Notification No. 1604, Nov. 1, 1999, Ministry of Health and Welfare, Japan) and the OECD guidelines for the testing of chemicals by performing the bacterial reverse mutation (Ames) assay, the in vitro chromosomal aberration assay, and the in vivo comet assay (alkaline single cell gel electrophoresis) in rat liver. In the Ames assay, 2,6-DNT was moderately positive irrespective of metabolic activation. In the in vitro chromosomal aberration assay, under conditions where the test substance would precipitate out, weak structural aberrations were observed with or without S9 mix at each dose at which the cell growth rate was about 40 to 50%. The in vivo comet assay yielded positive results in rat liver; that is to say, the increases in % tail DNA in liver in the 25 and 50 mg/kg groups were observed statistically significantly and dose-dependent. Our findings are in accordance with previous findings in the in vivo/in vitro unscheduled DNA synthesis (UDS) assay in rat liver and in a young rat liver micronucleus assay, although the rat bone marrow micronucleus assay gave negative results. These results suggest that test systems using liver are a useful method for the in vivo genotoxicity assessment of chemicals that require metabolic activation.  相似文献   
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994.

Objective  

The diagnosis of primary central nervous system lymphoma (PCNSL) in immunocompetent patients with atypical magnetic resonance (MR) findings such as disseminated lesions or no (non-enhancing) lesion is sometimes difficult because of mimicking other tumorous and non-tumorous diseases. Positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) and 11C-methionine (MET) can measure the glucose and amino acid metabolism in the lesions and may provide useful information for diagnosing PCNSL in patients with such subtle MR findings.  相似文献   
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996.
997.
Objective: To perform a postmarketing surveillance study evaluating the safety and effectiveness of abatacept in Japanese patients with rheumatoid arthritis (RA).

Methods: Safety and effectiveness data were collected for all RA patients (at 772 sites) treated with intravenous abatacept between September 2010 and June 2011. Patients were treated by the approved dosing regimen according to the package insert. Treatment effectiveness was evaluated at baseline and at weeks 4, 12, and 24 using Disease Activity Score 28 (DAS28) according to erythrocyte sedimentation rate or serum C-reactive protein concentrations.

Results: Overall, 3882 and 3016 abatacept-naïve RA patients were included in safety and effectiveness analyses, respectively. Adverse drug reactions (ADRs) were reported for 15.66% of patients and serious ADRs were detected for 2.52% of patients. The incidence of serious infections was 1.03% and these were mainly attributed to different types of bacterial pneumonia. Disease activity improved significantly over 6 months. Separate multivariate analysis identified predictors of severe ADR, and severe infections and factors predictive of clinically meaningful DAS28 improvement after 6 months of treatment with abatacept.

Conclusions: Abatacept was efficacious and well tolerated in a clinical setting. No new safety concerns were detected.  相似文献   
998.
The aim of this study was to assess the cognitive functions of patients with spinocerebellar ataxia type 6 (SCA6). We examined 13 patients with genetically confirmed SCA6 and 13 healthy control subjects matched for age, years of education, global cognitive status, and intellectual ability. We administered verbal memory (word recall and word recognition), executive function (digit span, category and letter fluency, Frontal Assessment Battery, and Trail Making Test-A and B), and visuospatial construction (figure copying) tests. We found that the patients with SCA6 had significantly lower scores on the demanding word recall and letter fluency tests compared to the control subjects, while word recognition was well preserved in the patients with SCA6. The other executive functions tested, as well as visuospatial construction, were preserved in the SCA6 group. However, although memory encoding and storage processes were preserved, the retrieval of memorized information concerning frontal function might be selectively affected in patients with SCA6 compared to in control subjects. The impaired word recall and letter fluency noted in patients with SCA6 were interpreted as being related to a word-retrieval disability. Such dysfunctions may be attributed to damage in the frontal-cerebellum circuit owing to SCA6.  相似文献   
999.
A 61-year-old man with tracheal adenoid cystic carcinoma (case 1) and a 28-year-old woman with benign tracheal stenosis (case 2) were treated with sleeve resection of the lower trachea through a median sternotomy and prophylactic omental wrapping. The resected tracheas were 4.5 cm (case 1) and 4.0 cm (case 2) in length. Both patients had an uneventful course after surgery despite postoperative irradiation in case 1 and preoperative infection with methicillin-resistant Staphylococcus aureus in case 2.  相似文献   
1000.
The parameters involved in the Disease Activity Score of 28 joints (DAS28) are not mutually independent, and the evaluation excludes ankle and foot joints. We developed a new quantitative and comprehensive assessment of the activity of rheumatoid arthritis (RA), called the handy rheumatoid activity score, with 38 joints (HRAS38), to overcome these disadvantages of DAS28. Forty-six RA patients who recently completed a 1-year infliximab therapy were evaluated for DAS28 (C-reactive protein; CRP) and HRAS38 at 0, 2, 6, 14, 22, 30, 38, 46, and 54 weeks. The 38-joint evaluation in HRAS38 includes 28 joints of DAS28 except for the shoulder joints, with the addition of ankle and metatarsophalangeal joints. The extent of joint swelling was rated on a scale of 0–3. The HRAS38 score is the cumulative sum of three parameters including: (1) a global assessment of disease activity [visual analog scale (VAS) 0–100 mm] by the patient, (2) swollen joint score based on a 38-joint assessment by a physician (0–114), and (3) serum concentration of CRP (mg/l). Scatter plots of HRAS38 and DAS28(CRP), and subsequent linear regression analysis demonstrated a statistically significant correlation between methodologies (r = 0.846, P < 0.0001). Infliximab treatment resulted in a statistically significant (P < 0.001) decrease in the mean HRAS38 score from 130.5 to 56.5 within 2 weeks of treatment and at 52 weeks of therapy scores were still reduced at 52.5. The mean DAS28(CRP) was also significantly (P < 0.001) reduced from a baseline value of 5.8 to 3.7 after 2 weeks treatment with a final value of 3.2 after 52 weeks of therapy. Infliximab reduced the progression of joint destruction by 85%, for terms before infliximab as determined by radiographic analyses. The degree of progression appeared to be associated with the mean HRAS38, although this observation was not shown to be statistically significant by regression analysis (r = 0.307). The HRAS38 score comprises minimal and independently acquired parameters and is an effective and comprehensive measure of disease activity in RA patients.  相似文献   
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