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51.
A 55-year-old man presented with a smoothly elevated solid choroidal mass with choroidal detachment in the temporal region of the left eye. Both fluorescein and indocyanine green angiography suggested a vascularized lesion such as an angioma. However, radiographic examination revealed a solid, circumscribed, dome-shaped mass. During a 3-month observation, the mass gradually enlarged and invaded the iris. The possibility of malignant melanoma could not be ruled out. Due to rapid and continued growth of the tumor, the eye was enucleated. Histopathologic examination revealed proliferation of spindle-shaped cells surrounding reticulin-positive vessels, which is characteristic of hemangiopericytoma. To our knowledge, this is only the fourth reported case of intraocular hemangiopericytoma and the first diagnosed in a male patient.  相似文献   
52.
PURPOSE: This 5-year longitudinal study investigated the acquisition of 6 English grammatical morphemes (i.e., regular and irregular past tense, 3rd person singular, progressive aspect -ing, copula BE, and auxiliary DO) by 10 native Mandarin-speaking children and adolescents in the United States (arrived in the United States between 5 and 16 years of age). The goals were to chart and compare the acquisition trajectories and levels of mastery across the morphemes, identify when age-related differences emerged and which forms they took. METHOD: Morphological proficiency was measured by the accuracy of these morphemes in obligatory contexts during spontaneous speech. RESULTS: The morphemes were mastered by different numbers of participants and showed different growth trajectories. Performance variance was partially predicted by age of arrival (AoAr) in the United States, with early arrivals achieving greater proficiency than late arrivals. However, such AoAr effects took several years to occur and only existed for 2 of the 6 morphemes (i.e., 3rd person singular and regular past tense). Growth curve analysis revealed that language environment was a stronger predictor of individual differences than AoAr. Results did not uncover age-related differences in the acquisition of tense versus non-tense-related morphemes, nor in regular versus irregular morphemes, nor in the error types. CONCLUSION: Findings support an Environmental account for age-related differences in 2nd language (L2) morphological acquisition. Results also indicate that the acquisition of some grammatical morphemes by school-aged immigrants takes several years to complete. As L2 learners exhibit some error types and difficulties similar to monolingual children with specific language impairment, caution needs to be taken when interpreting and using morphological errors as indicators of speech/language learning problems in this population.  相似文献   
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54.
Fexofenadine is a selective, nonsedating H(1)-receptor antagonist approved for symptoms of allergic conditions, which is mainly excreted into feces via biliary excretion. The purpose of this study is to investigate its pharmacokinetics in mice and rats to determine the role of P-glycoprotein (P-gp) in its biliary excretion. In mice, biliary excretion clearance (17 ml/min/kg) accounted for almost 60% of the total body clearance (30 ml/min/kg). Comparing the pharmacokinetics after intravenous and oral administration indicated that the bioavailability of fexofenadine was at most 2% in mice. Knockout of Mdr1a/1b P-gp did not affect the biliary excretion clearance with regard to both plasma and liver concentrations, whereas the absence of P-gp caused a 6-fold increase in the plasma concentration after oral administration. In addition, the steady-state brain-to-plasma concentration ratio of fexofenadine was approximately 3-fold higher in Mdr1a/1b P-gp knockout mice than in wild-type mice. Together, these results show that P-glycoprotein plays an important role in efflux transport in the brain and small intestine but only a limited role in biliary excretion in mice. In addition, there was no difference in the biliary excretion between normal and hereditarily multidrug resistance-associated protein 2 (Mrp2)-deficient mutant rats (Eisai hyperbilirubinemic rats) and between wild-type and breast cancer resistance protein (Bcrp) knockout mice. These results suggest that the biliary excretion of fexofenadine is mediated by unknown transporters distinct from P-gp, Mrp2, and Bcrp.  相似文献   
55.
A 59-year-old male had a fluctuating large mass on the sacral region existed after birth. Sagittal MRI (T1-weighted image) disclosed a large fluid space in the mass and also revealed that sacral nerves extended caudally in the cyst. Enlargement of the sac may result in stretching of the spinal cord.  相似文献   
56.
Prostate carcinomas are well known to be initially responsive to endocrine therapy. However, a significant number of the patients experience a relapse from endocrine therapy during the follow-up period. We clinically analyzed various aspects of the relapse which indicate a limitation in the effectiveness of endocrine therapy for prostate carcinoma. In a total of 372 patients, 117 (31.5%) had some evidence of local relapse such as regrowth of the primary lesion, or a generalized relapse such as re-elevation of total acid phosphatase, reactivation of previously present metastasis or the new appearance of metastasis, during endocrine therapy. Of these, one-fourth had local relapse alone and the remainder showed generalized relapse. The interval from the start of the treatment to the time of relapse tended to become shorter; 45.9 months (mean) in stage B, 36.8 in stage C and 29.3 in stage D, according to the stage progression. As to the non-relapse rate of the primary lesion, no differences were found among the stage, with the rate being approximately 90% at the fifth year in each stage. However, the generalized relapse-rate tended to increase with the stage progression. In the generalized relapse, the patients of stage C or D showed a non-relapse rate of 71.7% or 67.4%, respectively. Most of the generalized relapse appeared within five years following start of endocrine therapy in these advanced stages. The interval from relapse to prostate carcinoma-related death in patients with the generalized relapse was 9 approximately 21 months, and those in stage D tended to show a a poorer prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
57.
The relationship between changes in blood coagulation and fibrinolysis during pregnancy and intrapartum-postpartum bleeding was studied as a trial prediction of abnormal bleeding during vaginal delivery in 27 subjects without any complications. The following results were obtained: In the third trimester, shortening of prothrombin time and activated partial thromboplastin time, increases in fibrinogen, platelet epinephrine, collagen aggregation, and plasminogen, and a decrease in alpha 2-plasmin inhibitor were marked as compared with those in the first trimester. In the same subjects, the relationship between changes in blood coagulation and fibrinolysis in the first and third trimesters and intrapartum-postpartum bleeding was studied by the independent matched pair test. There were significant correlations (p less than 0.005, p less than 0.001) between prothrombin time (r = -0.68862) and activated partial thromboplastin time (r = -0.77027). In the subjects whose prothrombin time and activated partial thromboplastin time in the third trimester were shorter than those in the first trimester, intrapartum and postpartum bleeding increased. The subjects whose prothrombin time and activated partial thromboplastin time in the third trimester were less by more than 0.52 seconds and more than 3.98 seconds, respectively, than those in the first trimester experienced abnormal bleeding exceeding 500 ml during delivery. In the intrapartum and postpartum bleeding group, shortening of prothrombin time and activated partial thromboplastin time, decreases in fibrinogen and alpha 2-plasmin inhibitor and an increase in platelet aggregation were more significantly observed than in the intrapartum and postpartum normal bleeding groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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59.
An epizootic of focal epithelial hyperplasia (FEH) or Morbus Heck in a pygmy chimpanzee (Pan paniscus) colony is described. Papovavirus-like particles were observed in the nuclei of epithelial cells. Analysis of the DNA of the lesions revealed an episomal papillomavirus-specific band with a molecular size of approximately 8,000 bp. In situ hybridization under high stringency conditions showed cross-hybridization between the chimpanzee papillomavirus DNA and human papillomavirus (HPV) type 13. The latter virus is uniquely associated with oral disease in man. This is the first demonstration of the association of a HPV 13-related pygmy chimpanzee papillomavirus (PCPV) and oral epithelial hyperplasia in a nonhuman primate.  相似文献   
60.
We experienced three cases with anomalous right coronary arteries during aortic valve surgery. By rotating a Freestyle bioprosthesis by a subcoronary technique, the anomalous artery was secured in one patient. The anomalous artery was injured during the routine aortotomy incision in another patient; a saphenous vein graft was interposed between the ascending aorta and the separated artery. In the third patient, a subannular prosthetic valve was chosen to avoid obstructing the anomalous orifice.  相似文献   
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