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Slowly progressive aphasia without generalized dementia is a degenerative syndrome selectively affecting dominant hemisphere language areas. We report changes in regional glucose metabolism measured by positron emission tomography in two patients with this condition. Striking abnormalities of glucose utilization in the left cerebral cortex were demonstrated in both patients. The findings of other neurodiagnostic studies were relatively unremarkable. The first patient had a 3-year history of progressive anomia and impaired auditory verbal recall. An electroencephalogram was normal, and computed tomography showed mild left perisylvian atrophy. Positron emission tomography revealed profound hypometabolism in the left temporal regions. The second patient also had a 3-year history of progressive anomia. Electroencephalography, computed tomography, and magnetic resonance imaging scans were normal. Positron emission tomography showed a major reduction in left parietal glucose utilization, with a lesser decrement in left temporal metabolism. Neither patient demonstrated significant contralateral or global abnormalities such as those reported in positron emission tomographic studies of Alzheimer's disease with or without focal clinical features. These observations support the concept of adult-onset progressive aphasia without dementia as a clinical syndrome distinct from Alzheimer's disease.  相似文献   
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The purpose of this study was to assess the feasibility of PET imaging of oncogene VPAC1 receptors overexpressed in human breast cancer cells. METHODS: Vasoactive intestinal peptide (VIP) analog (TP3982) was synthesized to harbor a carboxy-terminus lysine (Lys) residue separated from VIP-asparagine (Asn(28)) by 4-aminobutyric acid (Aba) as a spacer. Lys was derivatized with diaminopropionic acid coupled to a pair of dibenzoylthioglycolic acid residues as protecting groups. The analog was labeled with (64)Cu at pH 9 ((64)Cu-TP3982) and (99m)Tc at pH 12 ((99m)Tc-TP3982). (99m)Tc-TP3982 and VIP derivatized with Aba-GAGG and labeled with (99m)Tc ((99m)Tc-TP3654) were used as reference agents. Smooth muscle relaxivity assays performed with each derivative and compared with unaltered VIP(28) demonstrated functional integrity. In vitro stability of (64)Cu-TP3982 was determined by challenging the complex with 100-mol excess of diethylenetriaminepentaacetic acid (DTPA), human serum albumin (HSA), and cysteine. In vivo stability was determined in urine and serum for up to 24 h. The mass of the Cu-TP3982 complex was determined by mass spectrometry. Human T47D breast tumor xenografts were grown in athymic nude mice. Planar scintigraphic imaging was performed at 4 and 24 h after the intravenous administration of (99m)Tc-TP3982 and (99m)Tc-TP3654 and PET imaging was performed using a small animal MOSAIC PET scanner, also at 4 and 24 h after injection of (64)Cu-TP3982. Tissue-distribution studies were also performed. In a separate experiment, receptors were blocked by intravenous injection of authentic VIP(28) 30 min before the administration of (64)Cu-TP3982 and tissue distribution was examined. RESULTS: (64)Cu-TP3982 labeling yields were 98% +/- 1.2% and those for (99m)Tc-TP3982 and (99m)Tc-TP3654 were 98.2% +/- 1.1% and 97% +/- 1.6%, respectively. The biologic activity of both VIP analogs was uncompromised. When (64)Cu-TP3982 was challenged with 100-mol excess of DTPA, HSA, or cysteine, >98% radioactivity remained as (64)Cu-TP3982. In vivo, >98% of (64)Cu circulating in plasma remained as (64)Cu-TP3982. Of the (64)Cu excreted in urine 4, 20, and 24 h after injection, >98%, 89.9% +/- 0.9%, and 85% +/- 3%, respectively, were bound to TP3982. The mass of Cu-TP3982 as determined by surface-enhanced laser desorption/ionization time of flight (SELDI-TOF) was 4,049.7 Da. Four hours after receptor blocking with VIP(28), there was a significant reduction in uptake of all tissues except in the liver. With (64)Cu-TP3982, the 4-h postinjection tumor uptake was 10.8 +/- 2.1 %ID/g versus 0.5 +/- 0.02 %ID/g and 0.24 +/- 0.08 %ID/g for (99m)Tc-TP3982 and (99m)Tc-TP3654, respectively. Twenty-four hours after injection, the corresponding numbers were 17 +/- 0.7 %ID/g, 0.77 +/- 0.1 %ID/g, and 0.23 +/- 0.1 %ID/g. The severalfold greater uptake (21.2-74) of (64)Cu-TP3982 is attributable to the in vivo stability of the agent. CONCLUSION: The results suggest that the uncompromised biologic activity and the significantly greater tumor uptake of (64)Cu-TP3982, combined with the high sensitivity and enhanced resolution of PET imaging, make (64)Cu-TP3982 highly desirable for further studies in PET imaging of oncogene receptors overexpressed in breast and other types of cancers.  相似文献   
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Pyomyositis--tropical and nontropical   总被引:1,自引:0,他引:1  
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One hundred consecutive Tc-99m IDA hepatobiliary scans were reviewed revealing 14 scans (14%), that showed nonvisualization of the common bile duct (CBD), gallbladder (GB), and small bowel (SB), but good hepatic uptake of Tc-99m IDA derivative, a pattern designated by us as "the liver scan appearance." In 11 of 14 cases (79%), the diagnosis of complete CBD obstruction was confirmed by surgery, percutaneous transhepatic cholangiogram (PTC), endoscopic retrograde cholangiopancreatography (ERCP), and/or percutaneous needle biopsy (PBx). Common bile duct obstruction was suspected but not proven in the other three cases. The cholescintigraphic, ultrasound, PTC, ERCP, intraoperative cholangiogram, clinical, laboratory, and surgical findings are presented and correlated. The "liver scan-appearance" by cholescintigraphy should suggest a diagnosis of complete common bile duct obstruction; however, it does not specifically differentiate between stone or tumor as the cause of obstruction.  相似文献   
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Lasers in Medical Science - Diabetes mellitus is mostly interrelated to deficiency in wound healing. Low-level laser therapy has been shown to exert reliable effects on the acceleration of wound...  相似文献   
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Hepatocellular carcinoma (HCC), represents more than 85% of liver cancers. The diagnosis of HCC may be delayed due to the absence of early, sensitive and specific biomarkers. This study was conducted to investigate whether the expression of thioredoxin (Trx) and glutaredoxin (Grx) is helpful for HCC diagnosis in an experimental model. Twenty male albino rats were equally divided into two groups (HCC and control). Hepatocarcinogenesis was performed by single intraperitoneal (i.p) injection of 200?mg/kg of diethylnitrosamine (DENA). Two weeks later, 0.05% of phenobarbital (PB) was supplied in the drinking water for other 14 weeks. HCC was diagnosed by measuring serum alpha-fetoprotein (AFP) level and histopathological examination. Our results found that hepatic indices alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin were elevated but decreased total protein level. Lipid peroxidation was elevated through increasing hepatic content of MDA with decreased antioxidant parameters like hepatic SOD, CAT activities and GSH. The current study also found that Trx and Grx tissue genes were overexpressed in HCC group significantly, compared to control group. This study substantiated that increased expression of these enzymes may be predictive of outcomes in HCC.  相似文献   
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Journal of NeuroVirology - As the SARS-COV-2 becomes a global pandemic, many researchers have a concern about the long COVID-19 complications. Chronic fatigue syndrome/myalgic encephalomyelitis...  相似文献   
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