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81.
The authors report a 50-year-old man with progressive left hemispheric atrophy, cognitive decline, infrequent seizures, and spells suggestive of complicated migraine. They discuss the association between migraine and cerebral hemiatrophy and suggest that the spectrum of acquired cerebral hemiatrophy may be broader than what has been commonly recognized.  相似文献   
82.
The biophysical mechanisms that drive and regulate cardiac looping are not well understood, but mechanical forces likely play a central role. Previous studies have shown that cardiac torsion, which defines left-right directionality, is caused largely by forces exerted on the heart tube by a membrane called the splanchnopleure (SPL). Here we show that, when the SPL is removed from the embryonic chick heart, torsion is initially suppressed. Several hours later, however, normal torsion is restored. This delayed torsion coincides with increased myocardial stiffness, especially on the right side of the heart. Exposure to the myosin inhibitor Y-27632 suppressed both responses, suggesting that the delayed torsion is caused by an abnormal cytoskeletal contraction. This hypothesis is supported further by computational modeling. These results suggest that the looping embryonic heart has the ability to adapt to changes in the mechanical environment, which may play a regulatory role during morphogenesis.  相似文献   
83.
Despite the common occurrence of pleomorphic adenoma of major salivary glands, intranasal pleomorphic adenoma are rare. We present a ease of pleomorphic adenoma of the nasal septum along with a brief review of literature. The histological nature of this lesion in comparison to other salivary gland tumours and the importance of an accurate diagnosis has been stressed.  相似文献   
84.
BACKGROUND: The advantage of 4-field radiation to the pelvis is that the use of lateral portals spares a portion of the small bowel anteriorly and rectum posteriorly. The standard lateral portals defined in textbooks are not always adequate especially in advanced cancer cervix. METHODS: An analysis was done to determine adequacy of margins of standard lateral pelvic portals with CECT defined tumor volumes. The study included 40 patients of FIGO stage IIB and IIIB treated definitively for cancer cervix between 1998 and 2000. An inadequate margin was defined if the cervical growth and uterus were not encompassed by the 95% isodose. RESULTS: An inadequate posterior margin was common with bulky disease (P = 0.06) and with retroverted uterus (P = 0.08). Menopausal status, FIGO stage, associated myoma, and age were of no apparent prognostic significance. Bulk retained significant on multivariate analysis. An inadequate anterior margin was common in premenopausal (P = 0.01); anteverted uterus (P = 0.02); associated myoma (P = 0.01); and younger patients (P = 0.03). It was not influenced by bulk or stage. Menopausal status and associated myoma retained significant on multivariate analysis. CONCLUSION: Without the knowledge of precise tumor volume, the 4-field technique with standard portals is potentially risky as it may under dose the tumor through lateral portals and the standard AP/ PA portals are a safer option.  相似文献   
85.
OBJECTIVES: To evaluate the efficacy of oral lycopene therapy in patients with oral submucous fibrosis and to compare these effects with a placebo. STUDY DESIGN: Fifty-eight patients with oral submucous fibrosis formed the population for the study and were randomly divided into 3 groups, evaluated weekly over a 2-month period. Patients of group A (n = 21) received 16 mg of lycopene, those of group B (n = 19) received 16 mg of lycopene along with biweekly intralesional steroid injections, and those of group C (n = 18) were given a placebo. Paired and unpaired t tests were used for statistical evaluation. RESULTS: Mouth-opening values for the patients showed an average increase of 3.4 mm, 4.6 mm, and 0.0 mm for patients in groups A, B, and C, respectively. These values were statistically found to be highly significant. CONCLUSIONS: The observed effects suggest that lycopene can and should be used as a first line of therapy in the initial management of oral submucous fibrosis.  相似文献   
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88.
A 48 year old male presented with a one and a half year history of a progressively increasing, asymptomatic lump in the left hypochondrium and no history of hematuria. His general physical examination was unremarkable, and an abdominal examination revealed a large, firm, irregular and tender mass in the left hypochondrium extending into the lumbar region. Chest X-ray was normal. An intravenous urogram revealed a normally functioning right kidney with non-visualization of the left kidney. CT-scan of the abdomen revealed a large, mixed attenuating mass replacing the left kidney. At laparotomy, a large, fleshy, well-encapsulated tumor was found in the left kidney with no surrounding infiltration and a left radical nephrectomy was performed. Microscopic examination revealed a poorly differentiated tumor comprised of small round cells with focal areas of abortive embryonal tubular and glomerular differentiation suggestive of Wilms' tumor. The patient was advised chemotherapy and radiotherapy but he absconded and was lost to follow-up.  相似文献   
89.
Pulmonary functions were measured in 15 patients with severe chronic anaemia (haemoglobin level < 5 g/dl). The measurements were repeated after correction of anaemia (Hb > 10 g/dl). Twenty age and sex matched, asymptomatic, non-smoker subjects served as controls. There was 80-100% improvement in various lung functions after correction of anaemia. Effort dependent parameters, viz FVC, ERV, IC, MVV were low in anaemic patients which improved with the rise of haemoglobin. The TLCO, DM, VC, KCO were not significantly influenced during anaemic state. FEV1, PEFR, RV/TLC were essentially normal. We conclude that the observed changes produced in lung functions during anaemic state are fully reversible after its correction.  相似文献   
90.
Protein A is an immunostimulating glycoprotein obtained from Staphylococcus aureus Cowan I. Its antitumour activity is proven in various tumour models. Its ability to provide protection against tumour initiation by the chemical carcinogen 7,12-dimethylbenzanthracene (DMBA) has been investigated in the present study using a mouse skin model of two-stage carcinogenesis. Protein A was administered intraperitoneally (1 microgram/animal 20 g body wt.) twice a week for 2 weeks, prior to initiation by DMBA. The promotion was performed by twice weekly applications of 12-O-tetradecanoyl phorbol-13-acetate (TPA) (3 or 5 micrograms/animal in 100 microliters acetone). Protein A provided significant protection to animals from DMBA-induced tumour initiation as was observed by the decrease in cumulative number of tumours, percent of animals developing tumours, number of tumours per animal and rate of tumour growth. Our data indicate that protein A has anticarcinogenic properties.  相似文献   
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