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1.
OBJECTIVE: To compare laser-assisted tympanostomy (LAT) with radiofrequency myringotomy (RFM), as well as the effectiveness of mitomycin C (MC) on the above techniques, in rabbits. STUDY DESIGN: Experimental animal research protocol. SETTING: University of Crete, School of Medicine, Medical Experimental Education and Research Center. METHODS: Bilateral myringotomies were performed under general anesthesia on 40 rabbits. LAT was performed on 20 animals (40 ears) and RFM on the remaining 20 animals (40 ears). MC (0.3 mg/mL) pledgets were applied to the right ears and saline pledgets to the left ears. Animals were monitored weekly using otomicroscopy until myringotomy closure. Kaplan-Meier survival techniques were used to compare myringotomy patency times. INTERVENTIONS: Under general anesthesia, bilateral LAT was performed on 20 rabbits and bilateral RFM on 20 rabbits. MAIN OUTCOME MEASURES: Myringotomy patency time. RESULTS: The mean patency times of the saline-treated ears were: 1.85 weeks (95% confidence interval [CI], 1.556-2.144 wk) for the LAT group and 1.70 weeks (95% CI, 1.494-1.906 wk) for the RFM group. This difference was not significant (p > 0.5). MC application significantly prolonged mean patency time (p < 0.0001) in both LAT and RFM groups. The mean patency times in the MC-treated ears were 5.45 weeks (95% CI, 5.226-5.674 wk) for the LAT group and 5.55 weeks (95% CI, 5.285-5.815 wk) for the RFM group. This difference was not significant (p > 0.5). CONCLUSION: There is no significant difference in myringotomy patency times between LAT and RFM techniques in rabbits, whereas MC significantly prolongs the patency rate of either technique.  相似文献   
2.
A high intake of olive oil has produced high levels of high-density and low levels of low-density lipoprotein cholesterol in short-term dietary trials. To investigate long-term effects of olive oil we have studied the diet and serum lipids of boys in Crete, where a high olive oil consumption is the norm. Seventy-six healthy rural Cretan boys aged 7-9 years were studied. The diet was assessed by a 2-day dietary recall. Blood was collected according to a standardized protocol and sera were analyzed in a rigidly standardized laboratory. The mean daily intake of energy was 11.0 MJ (2629 kcal). The intake of fat (45.0% of energy) and oleic acid (27.2% of energy) was high, and that of saturated fat low (10.0% of energy), reflecting a high consumption of olive oil. The high consumption of olive oil was confirmed by a high proportion of oleic-acid (27.1%) in serum cholesteryl fatty acids. Mean concentration of serum total cholesterol was 4.42 mmol l-1 (171 mg dl-1), of HDL-cholesterol 1.40 mmol l-1 (54 mg dl-1), of serum triglycerides 0.59 mmol l-1 (52 mg dl-1), of apo-AI 1210 mg l-1 and of LDL apo-B 798 mg l-1. The body mass index of the Cretan boys (18.2 kg m-2) was on average 2 kg m-2 higher than that of boys from other countries. Contrary to our expectation, the Cretan boys did not show a more favourable serum lipoprotein pattern than boys from more westernized countries studied previously using the same protocol. Our hypothesis that a typical, olive-oil-rich Cretan diet causes a relatively high HDL- to total cholesterol ratio is not supported by the present findings.  相似文献   
3.

Background  

Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking.  相似文献   
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Segel  MC; Paulus  DD; Hortobagyi  GN 《Radiology》1988,169(1):49-54
The response to induction chemotherapy is an important prognostic factor in patients with nonmetastatic, locally advanced breast carcinomas. Assessment at mammography of the response of 60 breast cancers in 59 women was performed between 1974 and 1986. Responses were excellent in 13 tumors, moderate in 34, and poor in 13 (excellent moderate = 78%). Assessment of response of discrete masses in a fatty breast was easiest; assessment of response of tumor areas that were poorly defined-such as a focal area of architectural distortion or mass in dense breast parenchyma-was more difficult. Of 17 patients with excellent pathologic responses-that is, minimal or no residual tumor-15 (88%) had complete responses (no residual tumor) as determined with mammography, physical examination, or both. Mammography provides information complementary to physical examination and is essential in the accurate assessment of the response to chemotherapy of locally advanced breast cancer.  相似文献   
6.
Summary Recognition of adrenal atrophy during a review of autopsy findings in two sisters who died at 8 months and 3 1/2 years prompted estimation of very long chain fatty acids, phytanic acid and pristanic acid on wet liver fixed in formalin for 12 years. These were shown to be markedly increased and defects in multiple peroxisomal functions and decrease in particulate catalase were shown in cultured fibroblasts, confirming an abnormality of peroxisomal biogenesis. The patients had presented with failure to thrive, recurrent diarrohea and vomiting, poor mental development, retinal pigmentation, blindness and in the older patient deafness, with only mild dysmorphic features. Autopsy in the older patient showed adrenal atrophy, cirrhosis, and foamy histiocytes in multiple organs. The brain showed no demyelination, little cytoarchitectural abnormality, occasional perivascular histiocytes in the grey matter and meninges and prominent Purkinje cells in the molecular layer of the cerebellum. In the younger patient the changes were very subtle in spite of the marked clinical similarity. Despite the young age at death the clinicopathological features are most suggestive of infantile Refsum disease. In many situations anatomical pathology can be very useful in the recognition and study of peroxisomal disorders.  相似文献   
7.
Summary Unusual inclusions with some of the features of reducing bodies were encountered in the skeletal muscle biopsy of a 2.5-year-old boy with childhoodonset acid maltase deficiency. The biopsy revealed a vacuolar myopathy with lysosomal storage of glycogen and eosinophilic refractile inclusions in myofibers, which appeared dark blue with the menadione-nitroblue tetrazolium reaction. The significance of the association of inclusions with reducing properties in the setting of acid maltase deficiency is discussed.  相似文献   
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Recent research has shown that neovascularization, quantitated by microvessel density (MVD), constitutes a strong prognostic indicator in patients with invasive urothelial carcinomas. These studies, however, have focused only on MVD as the only factor reflecting angiogenesis in transitional-cell carcinomas (TCCs). The objective of this report was to evaluate multiple morphometric microvascular characteristics besides MVD in superficial and muscle-invasive TCCs separately, to provide a better approach to the relationship between angiogenesis, clinicopathological parameters, and prognosis. Histologic sections from 115 TCCs [35 superficial (T1) and 80 muscle-invasive] were immunostained for CD31 and evaluated using image analysis for the quantitation of MVD, area, total vascular area, major axis length, minor axis length, perimeter, compactness, shape factor, and Feret diameter. Patients were followed-up until death (n=31) or for an average of 42.2 months (median 38.5 months). MVD increased with progressing T category (P=0.049) but area (P=0.033), major axis length (P=0.022), perimeter (P=0.043), and Feret diameter (P=0.042) were highest in T2 tumors. Area was the single independent predictor of adverse significance in T1 TCCs, whereas for muscle-invasive tumors, survival was independently predicted by MVD. Regarding disease-free survival in superficial tumors, the single significant independent parameter was compactness, whereas area was an independent favorable indicator of disease-free survival for patients with invasive TCCs. It is concluded that the prognostic significance of neovascularization is better assessed by area and shape-related morphometric characteristics, whereas MVD becomes influential only with regard to overall survival of patients with invasive tumors.  相似文献   
10.
We have constructed a contig of non-chimaeric yeast artificialchromosomes (YACs) across the candidate region for childhoodautosomal recessive spinal muscular atrophy (SMA) In 5q13. Anovel microsatellite reduces the candidate region to approximately400kb of DNA distal to D5S435. The candidate region containsblocks of chromosome 5 specific repeats which have copies on5p as well as elsewhere on 5q. Restriction mapping of the YACsreveals at least one CpG island In the SMA gene region. TheYAC maps indicate that the contig contains minimal rearrangementsor deletions. The data show the value of screening several YAClibraries simultaneously in order to construct a set of overlappingsequences suitable for candidate gene searches and direct genomicsequencing.  相似文献   
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