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971.
The position of a visual pattern moving within a static aperture appears to be displaced in the direction of motion. This illusory position shift can be induced by luminance-defined as well as contrast-defined motion. The present study used a random-dot binocular correlogram in which a moving square-wave grating was solely defined by binocular correlations. This cyclopean motion was found to induce illusory position shift. Consistent with previous reports on position shift induced by second-order motion, the illusion was smaller than that found in the case of the first-order motion. This pattern of results unequivocally demonstrates the existence of a binocular mechanism mediating this illusion.  相似文献   
972.
Abstract: For accurate assessment of the response to primary chemotherapy (PCT) for locally advanced breast cancer, we measured reduction in total tumor volume (TTV) by using three‐dimensional magnetic resonance imaging (3D MRI), and examined the relationship between this reduction and patient prognosis. Fifty‐one patients with locally advanced breast cancer were treated with four cycles of docetaxel (60 mg/m2) before surgery. Tumor size was measured with calipers, ultrasonography (US) and conventional two‐dimensional (2D) MRI before and after chemotherapy. TTV was measured with 3D MRI. These and other clinicopathological parameters were statistically analyzed to determine the prognosis for the patients. Median follow‐up time was 46 months (1–64 months). Of the 51 patients, 25 developed distant recurrences. Patients whose TTV decreased by 75% or more after PCT showed significantly better prognosis than others, while tumor size measured with calipers, US and 2D MRI showed no significant relationship with patient prognosis. Of the clinicopathological parameters, only reduction in TTV and histological grade showed a significant association with distant recurrence‐free survival (p = 0.03 and 0.02, log‐rank test), while stepwise multivariate Cox’s proportional hazards analysis identified TTV as the strongest independent prognostic factor. Reduction in TTV measured with 3D MRI can be a useful prognostic factor for patients with locally advanced breast cancer treated with PCT.  相似文献   
973.
We report an 11-year-old boy with undermasculinized genitalia and an abnormally expanded CAG repeat length at exon 1 of the androgen receptor (AR) gene. He had microphallus and scrotal hypospadias with chordee, and underwent urethroplasty at 4 years of age. At 11 years of age, a gonadotropin releasing hormone (GnRH) test yielded a relatively high leutinizing hormone (LH) response (0·7→20·4 IU/l) and a relatively low follicle-stimulating hormone (FSH) response (1·7→4·8 IU/l), and an human chorionic gonadotropin (hCG) test showed sufficient responses of testosterone (0·7→23·0 nmol/l) and dihydrotestosterone (0·38→2·95 nmol/l). The CAG repeat length was 44 for the boy and ranged from 12 to 32 for 100 control males. The DNA sequences of the AR gene were normal for the exons 1–8 and for the splice donor, splice acceptor and branch sites. The markedly expanded CAG repeat length appears to be relevant to the undermasculinized genitalia of this boy, because such an expandsion, which has previously been reported only in spinal and bulbar muscular atrophy, is known to reduce AR function.  相似文献   
974.
Abstract: Thirteen patients, who had recurrent esophageal varices after esophageal transection or esophagoproximal gastrectomy were treated by endoscopic injection sclerotherapy. Four patients successfully underwent emergency sclerotherapy to control active variceal hemorrhaging. Three of these patients and the remaining nine patients (including six rebleeding patients who were conservatively treated) underwent elective sclerotherapy. None of the patients had variceal rebleeding in the follow-up study with sclerotherapies. Only one patient with recurrent varices did not undergo any additional sclerotherapy following emergency treatment. In this study, no deaths occured nor any major complications. Minor complications such as low grade fever and chest pain were observed, but they were transient and disappeared within 2 or 3 days without specific treatments. It is concluded that endoscopic injection sclerotherapy is considered to be the most effective procedure for recurrent varice following surgery.  相似文献   
975.
976.

Purpose  

This paper describes the development and evaluation of a parallel prototype robot for vitreoretinal surgery where physiological hand tremor limits performance.  相似文献   
977.
Pneumomediastinum is a rare complication of dermatomyositis (DM) and Polymiositis (PM). We report here three cases of PM/DM who developed pneumomediastinum. First case was 61 years old woman with amyopathic dermatomyositis (aDM). Her aDM was complicated with skin ulceration due to vasculopathy, but complicated interstitial pneumonia was not severe. She developed subcutaneous emphysema and pneumomediastinum. Second case was 57 years old woman with DM, who had intractable skin phenomena and mild interstitial pneumonia. The patient became subcutaneous emphysema and pneumomediastinum following severe vasculopathy of skin. The last case was 63 years old man with PM. His PM was complicated with interstitial pneumonia. He had intractable respiratory symptom. Ten years later, he became subcutaneous emphysema and pneumomediastinum following pneumothorax. First and second cases suggest that their pneumomediastinum were due to vasculopathy. On the other hand, pneumomediastinum of the last patient seemed to be associated with interstitial pneumonia and steroid.  相似文献   
978.
BACKGROUND: Bisphosphonates, antiresorptive drugs, are widely used to treat osteoporosis patients. However, recent reports indicated that several osteoporosis patients who underwent long-term bisphosphonate therapy subsequently developed severe suppression of bone turnover. We investigated whether urinary crosslinked N-telopeptide of type I collagen (NTX), a bone resorption marker, in osteoporosis patients was highly suppressed during long-term treatment with alendronate or risedronate. METHODS: We investigated 87 primary osteoporosis outpatients who were treated with alendronate or risedronate for more than 2 years. All patients were women, with an average age of 72.6 years. Altogether, 49 patients were treated with alendronate and 38 with risedronate, and the average administration period was 3.5 years. We defined high suppression as NTX being reduced <9.3 nmol bone collagen equivalent/mmol.Cr and a 35% decrease from baseline. RESULTS: In total, 11 of 87 patients (12.6%) had high NTX suppression based on the above criteria. The incidences of high suppression of NTX at 1,2,3,and 4 years after starting the treatment were 0%, 1.1%, 11.9%, and 4.7%, respectively. The average age, bone mineral density, and NTX values at baseline and the administration period were not associated with high suppression of NTX during alendronate or risedronate treatment. Regarding suppression of NTX during long-term treatment, there was no significant difference between alendronate and risedronate. CONCLUSIONS: The results suggested that long-term treatment with bisphosphonates necessitates careful follow-up of the patients.  相似文献   
979.
The present study was undertaken to develop an animal model for endometrial neoplasms. A total of 107 female ICR mice, 10 weeks of age, were used and treated as follows: Group 1 (31 mice) was given intravaginal instillation of N-methyl-N-nitrosourea (MNU) solution (1 mg/100 g body wt.) once a week for three weeks and then fed diet containing 5 ppm 17/β-estradiol (E2) for 20 weeks, starting one week after the last exposure to MNU, Group 2 (30 mice) was given MNU alone. Group 3 (31 mice) was given E2 diet alone. Group 4 (15 mice) was fed the basal diet alone and served as the untreated control. At the termination of the experiment (week 23), all surviving mice were killed. Histopathological examination revealed that adenocarcinomas in the uterine corpus developed in mice of Groups 1-3, with a high incidence of endometrial hyperplasia. The incidence of endometrial carcinomas in Group 1 (15/31, 48%) was significantly higher than in Group 2 (2/29, 7%, P < 0.001) or Group 3 (7/31, 23%, P > 0.01). In the uterine cervix, small numbers of squamous cell carcinomas and pre-neoplastic lesions (dysplasias and hyperplasias) were also present in mice of Groups 13. In Groups 1 and 3, an increased E2/progesterone (P) ratio was observed. Thus, the results indicated that this medium-term model for endometrial neoplasms is useful for studying the pathogenesis of endometrial cancer and that an increased E2/P ratio is an important factor for the development of endometrial adenocarcinoma.  相似文献   
980.
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