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1.
The components and variations of glycosaminoglycan (GAG) in the growth of transplantable tumors derived from a spontaneous mouse mammary tumor were investigated. A 45-week-old ddY female mouse, obtained from Shizuoka Laboratory Animal Center, was found to have a bean-sized mass at the third mammary gland of the left side. The tumor mass was surgically excised and used for transplantation in the present study. This mammary tumor was histologically found to be Type B-adenocarcinoma. Transplantable mammary tumors consisted of the fibrous or edematous interstitium contained a large amount of GAG components, which was mainly hyaluronic acid (HA), dermatan sulfate (DS) and chondroitin sulfate A/C (ChS). In the analysis of GAG components, HA content was present in a large amount in logarithmic growth phase of transplanted mammary tumors, but it was markedly decreased in stationary phase. On the other hand, the contents of DS and ChS increased in stationary phase of the tumor growth, and these increases corresponded, histologically, with the propagation of the fibrous interstitial tissues.  相似文献   
2.
Spontaneous malignant fibrous histiocytoma (MFH) of the chest wall was found in a 10-year-old male Japanese white rabbit. Histologically, the MFH consisted mainly of areas of storiform, pleomorphic and myxoid patterns. Positive reactions for acid phosphatase (Ac-P), non-specific esterase (N-SE) and beta-glucuronidase (beta-GL) were demonstrated in fibroblast-like, histiocyte-like and giant cells. Moreover, a strongly positive fibronectin (FN) reaction was observed mainly in histiocyte-like and giant cells. In electron microscopy, tumor cells were composed morphologically of various types of cells such as fibroblast-like, histiocyte-like, undifferentiated and giant cells. This case was quite similar to those reported in man or other animals.  相似文献   
3.
To establish the polymerase chain reaction (PCR) method for detecting the XY cells in cases suspected to have the bovine freemartin syndrome, a PCR reaction test was conducted on blood from a normal bull diluted in blood from a normal cow. From the results obtained, it was shown that the Y-specific sequence was detectable down to a concentration of 0.1%. Various types of the bovine freemartin syndrome, which occurs in heterosexual twins, single-born sterile heifers, and heifers born with Acardius amorphus, were examined by the chromosome analysis and the PCR method. The Y-specific sequence was detected in all 26 cases that showed chromosome chimerism but which was absent in the 5 cases without a chimerism. The PCR method was found to be effective and convenient for quickly diagnosing the various types of bovine freemartin syndrome.  相似文献   
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Sleep and Biological Rhythms - Sleep problems and obstructive sleep apnea (OSA) increase with age and disturb life in old age. Positional therapy is one option to treat OSA, but the differences in...  相似文献   
7.
It is known that cisplatin induces the excretion of zinc from the urine and thereby reduces its serum concentration. However, the fluctuation of these trace elements during or after cisplatin-based chemotherapy has not been evaluated. To answer this question, we performed a clinical study in esophageal cancer patients undergoing cisplatin-based chemotherapy. Eighteen patients with esophageal cancer who were not able to swallow food or water orally due to complete stenosis of the esophagus were evaluated. The patients were divided into a control group [total parenteral nutrition (TPN) alone for 28?days, ten cases] and an intervention group (TPN with additional trace elements for 28?days, eight cases). The serum concentrations of zinc, iron, copper, manganese, triiodothyronin (T3), and thyroxin (T4), as alternative indicators of iodine, were measured on days?0, 14, and 28 of treatment, and statistically analyzed on day?28. In the control group, the serum concentration of copper was significantly decreased from 135.4 (day?0) to 122.1???g/ml (day?14), and finally to 110.6???g/ml (day?28, p?=?0.015). The concentration of manganese was also significantly decreased from 1.34 (day?0) to 1.17???g/ml (day?14) and finally to 1.20 (day?28, p?=?0.049). The levels of zinc, iron, T3, and T4 were not significantly changed. In the intervention group, the supplementation with trace elements successfully prevented these decreases in their concentrations. TPN with supplementary trace elements is preferable and recommended for patients who are undergoing chemotherapy in order to maintain the patients?? nutrient homeostasis.  相似文献   
8.

Background

Despite the high prevalence of gastroesophageal reflux disease (GERD), its risk factors are still a subject of controversy. This is probably due to inadequate distinction between reflux esophagitis (RE) and non-erosive reflux disease (NERD), and is also due to inadequate evaluation of adjacent stomach. Our aim is therefore to define background factors of RE and NERD independently, based on the evaluation of Helicobacter pylori infection and gastric atrophy.

Methods

We analyzed 10,837 healthy Japanese subjects (6,332 men and 4,505 women, aged 20–87 years) who underwent upper gastrointestinal endoscopy. RE was diagnosed as the presence of mucosal break, and NERD was diagnosed as the presence of heartburn and/or acid regurgitation in RE-free subjects. Using GERD-free subjects as control, background factors for RE and NERD were separately analyzed using logistic regression to evaluate standardized coefficients (SC), odds ratio (OR), and p-value.

Results

Of the 10,837 study subjects, we diagnosed 733 (6.8%) as RE and 1,722 (15.9%) as NERD. For RE, male gender (SC = 0.557, OR = 1.75), HP non-infection (SC = 0.552, OR = 1.74), higher pepsinogen I/II ratio (SC = 0.496, OR = 1.64), higher BMI (SC = 0.464, OR = 1.60), alcohol drinking (SC = 0.161, OR = 1.17), older age (SC = 0.148, OR = 1.16), and smoking (SC = 0.129, OR = 1.14) are positively correlated factors. For NERD, HP infection (SC = 0.106, OR = 1.11), female gender (SC = 0.099, OR = 1.10), younger age (SC = 0.099, OR = 1.10), higher pepsinogen I/II ratio (SC = 0.099, OR = 1.10), smoking (SC = 0.080, OR = 1.08), higher BMI (SC = 0.078, OR = 1.08), and alcohol drinking (SC = 0.076, OR = 1.08) are positively correlated factors. Prevalence of RE in subjects with chronic HP infection and successful HP eradication denotes significant difference (2.3% and 8.8%; p<0.0001), whereas that of NERD shows no difference (18.2% and 20.8%; p = 0.064).

Conclusions

Significantly associated factors of NERD are considerably different from those of RE, indicating that these two disorders are pathophysiologically distinct. Eradication of Helicobacter pylori may have disadvantageous effects on RE but not on NERD.  相似文献   
9.
An aldehyde oxidase, which oxidizes various aliphatic and aromatic aldehydes using O(2) as an electron acceptor, was purified from the cell-free extracts of Pseudomonas sp. KY 4690, a soil isolate, to an electrophoretically homogeneous state. The purified enzyme had a molecular mass of 132 kDa and consisted of three non-identical subunits with molecular masses of 88, 39, and 18 kDa. The absorption spectrum of the purified enzyme showed characteristics of an enzyme belonging to the xanthine oxidase family. The enzyme contained 0.89 mol of flavin adenine dinucleotide, 1.0 mol of molybdenum, 3.6 mol of acid-labile sulfur, and 0.90 mol of 5'-CMP per mol of enzyme protein, on the basis of its molecular mass of 145 kDa. Molecular oxygen served as the sole electron acceptor. These results suggest that aldehyde oxidase from Pseudomonas sp. KY 4690 is a new member of the xanthine oxidase family and might contain 1 mol of molybdenum-molybdpterin-cytosine dinucleotide, 1 mol of flavin adenine dinucleotide, and 2 mol of [2Fe-2S] clusters per mol of enzyme protein. The enzyme showed high reaction rates toward various aliphatic and aromatic aldehydes and high thermostability.  相似文献   
10.
Molecular Biology Reports - Pyridoxine (PN), one of the vitamers of vitamin B6, plays an important role in the maintenance of epidermal function and is used to treat acne and rough skin. Clinical...  相似文献   
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