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11.
In the previous study, we reported that exposure to bisphenol-A induced the potentiation of dopamine receptor functions in the mouse limbic area, resulting in supersensitivity to methamphetamine-induced pharmacological actions. The present study was undertaken to investigate whether prenatal exposure to bisphenol-A could produce morphological change in dopaminergic neuron and the pattern of expression of genes regulating the dopaminergic neuron development. Here we found that prenatal and neonatal exposures to bisphenol-A increased the tyrosine hydroxylase- and dopamine transporter-like immunoreactivities in the adult mouse limbic area. The present molecular biological study shows that chronic bisphenol-A treatment produced a significant decrease in the dopaminergic neuron development factors, sonic hedgehog and glial cell line-derived neurotrophic factor, which were also decreased by prenatal exposure to bisphenol-A. These results suggest that chronic exposure to bisphenol-A could disrupt the dopaminergic neurotransmission in the process of dopaminergic neuron development.  相似文献   
12.
Itraconazole is widely used to treat onychomycosis because of its significant therapeutic effects. An otherwise healthy 30-year-old man treated with itraconazole developed frequent premature ventricular contractions (PVC). He presented with a dry cough and palpitation. The results of 12-lead electrocardiography (ECG) were essentially normal, but Holter ECG revealed 17,484 (18%) uniform PVC, including 4 short runs among 96,930 beats/day. Another Holter ECG after withdrawing itraconazole revealed 1,032 premature atrial contractions but no PVC. The corrected QT interval was 0.39 s without itraconazole, 0.41 s with itraconazole, and 0.43 s when multiple PVC were documented. Itraconazole inhibits the fungal cytochrome P450 that is involved in fungal cell membrane formation, interrupts human cytochrome P450A4 in the liver and causes adverse interactions with various drugs such as antiarrythmics, but its cardiac side-effects are obscure. Both patients and physicians should be aware that itraconazole can cause PVC as a side-effect.  相似文献   
13.
BACKGROUND: Pathological changes in vein grafts begin immediately after arterial circulation is applied to the grafts. Chemical mediator stimulation and mechanical strain induce neointimal hyperplasia and medial thickening of the vein grafts, resulting in their failure. We investigated the inhibitory effect of locally applied cilostazol, an inhibitor of cyclic adenosine monophosphate phosphodiesterase III, on neointimal hyperplasia and medial thickening of the grafts. METHODS AND RESULTS: We established a distal anastomotic stricture model of femoral vein-abdominal aorta interposition grafting in rats. In this model, neointimal hyperplasia was observed not only at the distal anastomotic sites, but also in the graft body at postoperative day 14 and was markedly progressed at day 28. A strong expression of tenascin-C was found in the media and neointima of the graft body. In the grafts around which cilostazol was administered locally using Pluronic gel, neointimal hyperplasia was significantly suppressed compared with control grafts treated with the gel alone, with the mean neointimal cross-sectional area reduced by 87.1% for the graft body and by 78.9% for the distal anastomotic sites and mean medial cross-sectional area of the graft body reduced by 54.2% at day 28 versus the control. Cilostazol treatment decreased cell proliferation and the number of tenascin-C-producing cells seen by in situ hybridization, but the expression of tenascin-C protein was not suppressed. CONCLUSION: We concluded that a single perivascular application of cilostazol inhibits neointimal hyperplasia and medial thickening of vein grafts in a rat model.  相似文献   
14.
Pancreatic metastasis of malignant melanoma is rarely diagnosed while the patient is alive. We report a case of metastatic melanoma of the pancreas in a 35-year-old woman presenting with a solid mass of the pancreas. Her past medical history included a radical hysterectomy 2 years previously for malignant melanoma of the vagina. Twelve months later, lung metastasis was also resected. EUS-guided fine needle aspiration (EUS-FNA) identified that the pancreatic tumor was histologically and immunohistochemically identical to the surgical specimen of her lung neoplasm. Imaging studies including US, CT, and MRI have limited value to distinguish the tumors from primary ductal adenocarcinoma. EUS-FNA can provide tissue diagnosis from pancreatic masses, specifically when other modalities have failed.  相似文献   
15.
The purpose of our study is to evaluate whether the hamstring tendons can regrow after harvesting for anterior cruciate ligament (ACL) reconstruction and whether the regenerate tissue can be histologically characterized as tendinous. Eleven of the patients (eight female and three male; mean age, 23 years; range 17–37 years) consented to participate in this study. One year after the ACL reconstruction, surgical biopsy was done. Regeneration of the tendon was detected macroscopically in 9 of the 11 patients. Histologically and immunohistochemically, the regenerated tendons closely resembled normal ones. The results of this study show the hamstring tendons can regenerate after harvesting for the ACL reconstruction.  相似文献   
16.
OBJECTIVE: Although hypercalciuria, a well-established adverse effect of vitamin D3, can be a risk factor of renal stone formation, the risk of nephrolithiasis has not been well defined. The consumption of a diet high in acid precursors is often cited as a risk factor for the development of calcium-based kidney stones. In the present study, we investigated the effect of chronic acid ingestion on kidney stone formation in rats treated with calcitriol (1-25[OH]2 D3). METHODS: Control rats (C-C), calcitriol-treated rats (C-V; three treatments of 0.5 microg of calcitriol per week) and acid-ingested (water containing 0.21 mol/L NH4Cl), calcitriol-treated (three treatments of 0.5 microg of calcitriol per week) rats (A-V) were fed in metabolic cages. After 1 month, urine, blood, kidney and bone samples were analyzed. RESULTS: The A-V rats exhibited elevated serum calcium concentrations, urinary calcium and phosphate excretion, urinary type I collagen cross-linked N-peptide (NTx)/creatinine values, mRNA expression of osteopontin in the kidney, and renal calcium contents as well as decreased bone mineral densities, compared with the C-C and C-V rats. Urinary citrate excretion was lower and NaDC-1 mRNA expression in the kidney was higher in the A-V rats than in the C-C and C-V rats. Calcium phosphate kidney stones were found in the A-V rats. CONCLUSIONS: The ingestion of NH4Cl, an acid precursor, promotes calcium phosphate kidney stone formation in calcitriol-treated rats. The chronic intake of a diet rich in acid precursors may be a risk factor for the development of kidney stones in subjects who are being treated with calcitriol.  相似文献   
17.
This study was done to identify factors affecting present hospitalization versus home care in 4,578 elderly subjects representing 87.1% of the elderly population living in S. city near Osaka. Subjects or their families were asked by interviews regarding the age of the subjects, the kind of persons living together in the family unit, the kind of housing, the number of rooms in the family dwelling, and health conditions. Subjects were also asked whether he or she could walk unassisted and whether home care would be preferred in case of an illness. Among the 153 hospitalized subjects, ability to walk, age, and the number of rooms were all significant factors, in decreasing order. Among the 1,193 persons who preferred home care in case of an illness, the number of rooms, age, ability to walk, and the size of the family unit were all significant factors, in decreasing order. Among subjects who could not walk unassisted, the number of rooms was the main factor determining their admission and not preferring home care if their condition worsened. Thus, although the ability to walk is the major factor among the factors we investigated, housing conditions are also important if home care is to be possible.  相似文献   
18.
Theiler’s murine encephalomyelitis viruses (TMEV) are divided into two subgroups on the basis of their different biological activities. The GDVII strain produces acute polioencephalomyelitis in mice, whereas the DA strain produces demyelination with virus persistence in the spinal cord. A comparative study of GDVII and DA strains suggested that low host immune responses are responsible for the development of acute GDVII infection and that the persistence of infected macrophages plays a crucial role in the development of chronic white matter lesions in DA infection. All 78 mice infected with GDVII died or became moribund by day 13, while none of 54 mice infected with DA died. In the acute stage, the distribution of viral antigens in the central nervous system (CNS) tissue was similar in both GDVII and DA infections, although the virus titer was higher in GDVII infection. In DA infection, a substantial number of T cells were recruited to the CNS on day 6 when they were virtually absent in GDVII infection. The titer of neutralizing antibody was already high on day 6 in DA infection but was negligible in GDVII infection. Development of chronic paralytic disease from day 35 of the DA infection was accompanied by focal accumulation of viral antigen-positive macrophages in the spinal white matter. In addition, white matter lesions comparable to those in chronic DA infection were induced in the spinal cord within 7 days after intracerebral injection of DA-infected murine macrophages. Received: 26 June 1995 / Revised, accepted: 27 December 1995  相似文献   
19.
To estimate the degree of coagulopathy in abdominal sepsis, we measured the plasma levels of prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin III complex (TAT) and plasmin-alpha 2-plasmin inhibitor complex (PIC) by the enzyme-linked immunosorbent assay in 38 patients with disseminated intravascular coagulation (DIC). In 20 patients with DIC due to abdominal sepsis, plasma levels of F1 + 2, TAT and PIC were 2.6 nmol/l, 27.9 micrograms/l and 1.5 micrograms/ml, respectively, with a mean antithrombin III (AT III) activity of 41.7%. F1 + 2, TAT, PIC and AT III levels were 4.7 nmol/l, 75.8 micrograms/l, 8.8 micrograms/ml and 70.9% in 18 patients with DIC as the result of malignancy. Though AT III levels in DIC due to sepsis were lower than those in DIC due to malignancy, the levels of F1 + 2, TAT and PIC in the former were not significantly more increased than those in the latter. The plasma levels of F1 + 2 were positively correlated with TAT and PIC in DIC patients with malignancy; however, there was no correlation between F1 + 2 and TAT or PIC in DIC patients with sepsis. In addition, the levels of serum albumin in the two groups were similar. These results suggest that activation of coagulation and fibrinolytic systems may not be so prominent in cases of DIC due to abdominal sepsis, compared to related events in DIC due to malignancy. It is also suggested that the depletion of AT III in cases of sepsis is not only caused by a consumption related to intravascular coagulation or to an alternate distribution of protein.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
20.
A total of 267 infants and children who underwent the arterial switch operation for transposition of the great arteries in the 6 years before Jan. 1, 1988 in six main Japanese institutions were entered into this review. The current status of patients surviving more than 1 year after the operation were evaluated along with early operative results. One hundred forty-six patients had an intact ventricular septum, 103 had a significant ventricular septal defect, and 18 had so-called Taussig-Bing anomaly of the transposition type. Eighteen patients were less than 28 days of age, 73 were 1 to 5 months of age, and 176 were older than 6 months of age at the time of operation. The overall mortality rate was 35% in the first 3 years and 12% in the more recent 3 years. There was a significant difference between the overall mortality rate of primary and two-stage repair (22% versus 10%, p = 0.047) in patients with intact ventricular septum. The overall mortality rate in patients with type B or C coronary arteries of Yacoub, and Radley-Smith's classification was significantly higher than that of other types of arteries (86% versus 18%, p = 0.0001). A total of 156 patients survived more than 1 year after the operation, and 44 children (28%) were noted to have supravalvular pulmonary stenosis (greater than 20 mm Hg). This complication was more common in patients operated on in the newborn period. Trivial or mild aortic regurgitation was noted in 29 patients (19%) and was more common in patients with two-stage than with primary repair (24% versus 14%). Aortic regurgitation was significantly more prevalent in patients in whom coronary arteries were implanted into slits or U-shaped defects than in those whose arteries were implanted into punched-out holes made on the pulmonary root (28% versus 8%, p = 0.049). Normal sinus rhythm was present in 97% of 154 patients and left ventricular ejection fraction was within the normal range in 97% of 115 patients at catheterization 1 to 5 months after the operation.  相似文献   
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