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111.
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The frequency of primary small intestinal adenocarcinoma is increasing but is still low. Its frequency is approximately 3% of that of colorectal adenocarcinoma. Considering that the small intestine occupies 90% of the surface area of the gastrointestinal tract, small intestinal adenocarcinoma is very rare. The main site of small intestinal adenocarcinoma is the proximal small intestine. Based on this characteristic, dietary animal proteins/lipids and bile concentrations are implicated and reported to be involved in carcinogenesis. Since most nutrients are absorbed in the proximal small intestine, the effect of absorbable intestinal content is a suitable explanation for why small intestinal adenocarcinoma is more common in the proximal small intestine. The proportion of aerobic bacteria is high in the proximal small intestine, but the absolute number of bacteria is low. In addition, the length and density of villi are greater in the proximal small intestine. However, the involvement of villi is considered to be low because the number of small intestinal adenocarcinomas is much smaller than that of colorectal adenocarcinomas. On the other hand, the reason for the low incidence of small intestinal adenocarcinoma in the distal small intestine may be that immune organs reside there. Genetic and disease factors increase the likelihood of small intestinal adenocarcinoma. In carcinogenesis experiments in which the positions of the small and large intestines were exchanged, tumors still occurred in the large intestinal mucosa more often. In other words, the influence of the intestinal contents is small, and there is a large difference in epithelial properties between the small intestine and the large intestine. In conclusion, small intestinal adenocarcinoma is rare compared to large intestinal adenocarcinoma due to the nature of the epithelium. It is reasonable to assume that diet is a trigger for small intestinal adenocarcinoma.  相似文献   
113.
Taurine, an important factor in the living body, is essential for cardiovascular function and development and function of skeletal muscle, retina and central nervous system. In the present study, its effect on cardiovascular function was specifically taken into consideration. In hemodiafiltration (HDF) patients, the effect of taurine on patients with chronic heart failure (CHF), in whom dry weight was difficult to control, was evaluated. All patients who were subjected to regular HDF for 4 h three times per week at Joban hospital were included in this study. Patients with chronic heart failure, in whom dry weight was difficult to control (N = 4), were included in the evaluation of clinical status. X‐ray and echocardiography were determined before and after taurine treatment. Almost all patients were taking nitric acid, warfarin, anti‐platelet agents and vasopressors. Because vital signs were unstable in chronic heart failure, all cases withheld antihypertensive drugs during HDF. For unstable vital signs during HDF, pulmonary congestion was chronically recognized. After taurine was started, vital signs stabilized and lowering of dry weight was possible. In addition, X‐ray and cardiac diastolic failure on echocardiography improved. Taurine was effective for CHF patients on HDF in whom dry weight was difficult to control in spite of various medications.  相似文献   
114.

Background

Hearing impairment is a common problem in patients with mucopolysaccharidosis IV (MPS IV) throughout their life. Many of the adult patients with MPS IV exhibit permanent or severe hearing loss. However, there has been no systematic review of detailed audiological test results in MPS IV.

Materials and methods

Fourteen individuals with MPS IV (13 MPS IVA and 1 MPS IVB; aged between 12 and 38?years old) participated in the current study. We obtained auditory neurophysiological responses (auditory brainstem responses and otoacoustic emissions test) in addition to pure-tone audiometry and middle ear function tests (tympanometry and acoustic reflexes).

Results

The results indicated various levels and types of hearing loss with abnormal neurophysiological responses even in those patients with MPS IVA with normal pure tone thresholds. We also found a strong relationship between height (short stature is an indicator of skeletal severity) and hearing sensitivity as well as a strong relationship between height and outer hair cell function in the inner ear (measured by otoacoustic emissions) among MPS IVA patients.

Conclusion

The strong correlation between reduced height and hearing loss indicates that patients with severe skeletal dysplasia may be at higher risk of developing more severe hearing loss. More importantly, the spectrum of hearing disorders indicates that MPS IV patients should have annual neurophysiological hearing tests in addition to audiometric testing from an early age regardless of their skeletal severity to more carefully monitor disease progression.  相似文献   
115.
We investigated the diagnostic and prognostic value of p53 expression and proliferative activity, as indicated by the Ki-67, in endoscopic biopsy specimens. Specimens were immunologically stained with p53 and MIB-1 (Ki-67), and the MIB-1/Ki-67 labeling index (LI) was calculated. Classification of adenomas was based on findings of H&E-stained preparations into those with low- or high-grade atypia. Well-differentiated tubular and papillary adenocarcinomas were classified as carcinomas with low- or high-grade atypia. There were significant differences among the control and adenoma patients in MIB-1/Ki-67 LI (P < 0.05). No significant difference was identified between adenomas with high grade atypia and carcinomas with low grade atypia. The p53 expression was negative in all adenomas, but it was positive in 68.2% of carcinomas. The current study demonstrated that p53 protein expression in endoscopic biopsy specimens was of preoperative diagnostic value for carcinoma of the ampulla of Vater. The p53 protein positive tumors had a relatively higher malignant potential than p53 protein negative ones. The MIB-1/Ki-67 LI was useful in differentiating non-tumorous lesions from adenomas and adenomas with low- or high-grade atypia. The MIB-1/Ki-67 LI had a prognostic value because clinicopathological factors of carcinoma of ampulla of Vater correlated with MIB-1/Ki-67 LI.  相似文献   
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PURPOSE: To evaluate the image quality and vascular selectivity of MR venography of the head using an MP-RAGE technique when obtained with a body radiofrequency transmitter coil system. MATERIALS AND METHODS: A total of 24 patients were imaged with a head or body RF transmission system. Subtraction MRA was processed with 0.1 mmol Gd-DTPA administration, and signal-to-noise ratios of the vascular system were measured. Venous demonstration and selectivity were also assessed. RESULTS: MP-RAGE MR venography with a body transmission system showed almost the same signal intensity for the venous and arterial systems, resulting in nonspecific vascular demonstration, while the head transmission system showed semi-selective venograms owing to inflow-induced high signal on precontrast images. However, MRA with a body transmission system provided a 1.5- to 2.5-fold higher signal-to-noise ratios based on higher gradient performance and excellent demonstration of the head veins, especially those below the skull base. CONCLUSION: Although selective venography was difficult, MRA with a body transmission coil provided excellent vascular images of the brain.  相似文献   
119.
Objective To investigate obstetric outcomes in singleton pregnancies conceived by in vitro fertilization (IVF) to nulliparous women older than 35 compared to those of their younger counterparts. Methods Nulliparous women 35 years and older at delivery conceived by IVF (n = 89) were compared with nulliparous women 34 years and younger at delivery conceived by IVF (n = 48). Data included antenatal data, gestational age at delivery, maternal and neonatal complications and mode of delivery. Results The incidence of pregnancy-induced hypertension in the younger group was significantly higher than that in the elderly group (13 vs. 3.4%, P = 0.043). There were no measurable differences in other obstetric outcomes such as placental abnormality, premature delivery or neonatal asphyxia between the two groups. Conclusion The current results suggest that obstetric complications in pregnancies conceived IVF are attributed to mechanisms other than those depend on advanced maternal age.  相似文献   
120.
Usually, fetal asphyxia/demise because of umbilical cord entanglement and secondary cord occlusion is a unique characteristic of monoamniotic twin pregnancies. We present here a rare case of fetal asphyxia due to cord entanglement in a monochorionic diamniotic twin pregnancy complicated by 2nd-trimester single intrauterine demise. In this case, there was no amniocentesis or any other invasive intrauterine procedure performed during pregnancy.  相似文献   
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