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1.
We measured the levels of serum thyroglobulin (Tg) in 52 pregnant females at various stages and compared them with those of 15 age-matched nonpregnant females. Serum Tg was measured by a solid-phase immunoradiometric assay. In pregnant females, mean serum Tg levels at the first, second, early third, and late third trimesters were 8.4 (range; 1.3-18.0), 9.2 (1.7-25.6), 10.1 (1.8-22.8), and 12.1 ng/ml (5.3-25.2), respectively. The statistical comparison was made after logarithmic transformation of the data. The mean value only at the late third trimester was significantly higher than that of controls (mean; 6.0 ng/ml, range; 1.5-23.6), but each value was within the normal range. Although serum Tg levels have been reported to be high at the end of pregnancy, our results indicate that the Tg levels in females could be clinically interpreted without regard to the coexistence of pregnancy.  相似文献   
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Background

Helical tomotherapy (HT) and volumetric modulated arc therapy (VMAT) are both advanced techniques of delivering intensity-modulated radiotherapy (IMRT). Here, we conduct a study to compare HT and partial-arc VMAT in their ability to spare organs at risk (OARs) when stereotactic ablative radiotherapy (SABR) is delivered to treat centrally located early stage non-small-cell lung cancer or lung metastases.

Methods

12 patients with centrally located lung lesions were randomly chosen. HT, 2 & 8 arc (Smart Arc, Pinnacle v9.0) plans were generated to deliver 70 Gy in 10 fractions to the planning target volume (PTV). Target and OAR dose parameters were compared. Each technique’s ability to meet dose constraints was further investigated.

Results

HT and VMAT plans generated essentially equivalent PTV coverage and dose conformality indices, while a trend for improved dose homogeneity by increasing from 2 to 8 arcs was observed with VMAT. Increasing the number of arcs with VMAT also led to some improvement in OAR sparing. After normalizing to OAR dose constraints, HT was found to be superior to 2 or 8-arc VMAT for optimal OAR sparing (meeting all the dose constraints) (p = 0.0004). All dose constraints were met in HT plans. Increasing from 2 to 8 arcs could not help achieve optimal OAR sparing for 4 patients. 2/4 of them had 3 immediately adjacent structures.

Conclusion

HT appears to be superior to VMAT in OAR sparing mainly in cases which require conformal dose avoidance of multiple immediately adjacent OARs. For such cases, increasing the number of arcs in VMAT cannot significantly improve OAR sparing.  相似文献   
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The growth of Zygosaccharomyces soja was strongly inhibited by the addition of 10?2 m-monoiodoacetic acid and 10?3 m-potassium cyanide. The formation of a considerable amount of riboflavin was recognized after 5 days cultivation of this organism in presence of the aforementioned two inhibitors, and its growth was considerably improved after the formation and accumulation of riboflavin. Furthermore, the effect of the aforementioned two inhibitors upon the growth of this organism in young stage was compensated with the addition of riboflavin.  相似文献   
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The yeast hexokinase is highly specific for α-isomer of d-glucose. The relative rate of phosphorylation of β-d-glucose, catalyzed by the purified yeast hexokinase, is observed to be 60~70 (α-d-glucose=100). The average Michaelis constants of yeast hexokinase are found to be 1.8 × 10?4 and 2.4 × 10?4 for α-d-glucose and (β-d-glucose respectively, therefore the difference between the two constants is considered to be negligible.  相似文献   
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Background  

The construct validity of alexithymia and its assessment using the 20-item Toronto Alexithymia Scale (TAS-20) in Japan is unknown. Low reliability has been found for the third factor of the TAS-20 in some cultures, and the factor structure for psychosomatic disorder patients has not been adequately investigated. Although alexithymia most likely has certain developmental aspects, this has infrequently been investigated.  相似文献   
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Properties of Chitosanase from Bacillus cereus S1   总被引:3,自引:0,他引:3  
Chitosanase from Bacillus cereus S1 was purified, and the enzymatic properties were investigated. The molecular weight was estimated to 45,000 on SDS-PAGE. Optimum pH was about 6, and stable pH in the incubation at 40°C for 60 min was 6–11. This chitosanase was stable in alkaline side. Optimum temperature was around 60°C, and enzyme activity was relatively stable below 60°C. The degradations of colloidal chitosan and carboxymethyl cellulose (CMC) were about 30 and 20% relative to the value of soluble chitosan, respectively, but colloidal chitin and crystalline cellulose were not almost hydrolyzed. On the other hand, S1 chitosanase adsorbed on colloidal chitin completely and by about 50% also on crystalline cellulose, in contrast to colloidal chitosan, which it did not adsorb. S1 chitosanase finally hydrolyzed 100% N-deacetylated chitosan (soluble state) to chitobiose (27.2%), chitotriose (40.6%), and chitotetraose (32.2%). In the hydrolysis of various chitooligosaccharides, chitobiose and chitotriose were not hydrolyzed, and chitotetraose was hydrolyzed to chitobiose. Chitobiose and chitotriose were released from chitopentaose and chitohexaose. From this specificity, it was hypothesized that the active site of S1 chitosanase recognized more than two glucosamine residues posited in both sides against splitting point for glucosamine polymer. Received: 8 June 1999 / Accepted: 20 July 1999  相似文献   
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Neurochemical Research - Hippocampal oxidative stress has a vital role in the pathophysiology of Alzheimer’s disease (AD)-associated behavioral deficits. Ecdysterone (Ecdy), a natural product...  相似文献   
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