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81.
The thymoma-prone rat of the BUF/Mna strain is a useful model for human thymoma. In this strain thymoma development is regulated by a single autosomal susceptible gene, Tsr-1. At pre-thymoma age, BUF/Mna rats have extremely large thyrauses, when compared to those of other strains of rats. Genetic studies in crosses between BUF/Mna rats with large thymuses and WKY/NCrj rats with small thymuses suggested the presence of a major autosomal gene, Ten-1 , which contributes to thymus enlargement in a backcross population. Linkage studies between Ten-1 and microsatellite markers in backcross rats of (WKY/NCrj×BUF/Mna)Fl×BUF/Mna have led to the localization of Ten-1 in chromosome 1. This result may provide an approach to clone Tsr-1 , which could be allelic to Ten-1.  相似文献   
82.
The purpose of this study was to evaluate the acute effects of corticosteroid and iodide preoperative therapy in patients with Graves' disease in terms of thyroid function and immunological parameters. The above combination was prescribed for 4 patients who had experienced severe side effects from antithyroid drugs (ATD) in order to reduce the possibility of post-thyroidectomy thyroid storm. Corticosteroids were employed daily for four days, and iodides were given daily for two weeks prior to thyroidectomy. The free T3 values decreased rapidly to euthyroid levels following the administration of both drugs, although the free T4 values were still much higher than normal in 3 of the 4 patients at the time of surgery. By comparison, 3 of 8 patients treated with ATD also had thyroid hormone levels above normal. Studies of lymphocyte subsets revealed that the percentage of helper T cells was significantly less in the corticosteroidiodide treatment group than in the control and ATD groups. It is thus possible that postoperative thyroid storm might be prevented through corticosteroid-iodide therapy by virtue of the reduction of free T3 values to within the normal range by the time of surgery. The acute suppression of helper T cells was another result of this form of therapy observed.  相似文献   
83.
Surgical treatment for the recurrence of colorectal cancer   总被引:2,自引:0,他引:2  
We report the results of a retrospective study conducted on patients who developed recurrence following surgery for colorectal cancer, and present a practical plan to improve the survival rates. Of 974 patients who underwent surgery for colorectal cancer in our hospital during the 20 years between 1974 and 1993, 152 developed recurrence, as local recurrence in 70 (7.2%), as liver metastasis in 47 (4.8%), and as pulmonary metastasis in 35 (3.6%). The number of patients who underwent reoperation or curative resection was 54 (77.1%) and 13 (24.1%), respectively, of those with local recurrence, 16 (34.0%) and 6 (37.5%) of those with liver metastasis, and 6 (17.1%) and 6 (100.0%) of those with pulmonary metastasis. The 3- and 5-year survival rates were 13.4% and 8.9%, respectively, after reoperation for local recurrence, 14.4% and 0%, after reoperation for liver metastasis, and 53.3% and 53.3% after reoperation for pulmonary metastasis. Although evaluation was difficult owing to the small number of patients with lung metastasis, resection of a pulmonary lesion resulted in a good outcome. Furthermore, a significant difference in 3- and 5-year survival rates was observed between patients who underwent reoperation and those who underwent conservative treatment, for whom the survival rates were 0% and 0% following local recurrence, 4.6% and 0% following liver metastasis, and 0% and 0% following lung metastasis, at 3 and 5 years, respectively. These findings indicate that aggressive surgery for recurrence may result in a better outcome.  相似文献   
84.
A filing system for ocular fundscopic image data was developed by using a personal computer for the Twin AMHTS. The development of the system was tried as one of the data transfer system including image data between two similar AMHTSs named the Twin AMHTS through the information network system. The filing system is capable of storing 26782 data of ophthalmoscopic pictures with a data compression mode by using a magneto-optical disk (MOD) whose storage capacity of both sides is 616 MB. It takes no long time for retrieval and display of the image data in the filing system. Good quality of compression and decompression obtained and reproducibility of the ocular fundus picture is favorable regardless of normal or abnormal cases. As a result, it is suggested that the developed system has practical utility although it requires more improvement.  相似文献   
85.
Preconditioning of the brain with sublethal ischemia induces tolerance to subsequent lethal periods of ischemia (ischemic tolerance). In this study, we used NADPH-diaphorase histochemistry to investigate the postischemic changes of nitric oxide synthase (NOS) in the hippocampus in a rat model of cerebral ischemia and ischemic tolerance. Forebrain ischemia was induced by 4-vessel occlusion for 3 min as an ischemic preconditioning. Three days after the preconditioning or sham operation, second ischemia was induced for 6 min. A transient increase in NADPH-diaphorase activity, beginning after 2 h and maximal after 1 day, was observed in CA1 pyramidal neurons of rats subjected to 3 min of preconditioning ischemia as well as 6 min of subsequent ischemia both with and without preconditioning. In addition, expression of NADPH-diaphorase activity was seen in reactive glial cells in the damaged CA1 region of animals subjected to 6 min of ischemia without preconditioning. Thus, direct involvement of increased NADPH-diaphorase activity in ischemic tolerance was not suggested because the increased NADPH-diaphorase activity preceded the induction of ischemic tolerance which takes place 1–7 days after preconditioning. However, the present findings suggest that the induction of neuronal NADPH-diaphorase activity occurs in response to cerebral ischemia.  相似文献   
86.
The role of endoscopic retrograde cholangiopancreatography (ERCP) in the preoperative assessment of anomalous pancreaticobiliary junction was retrospectively evaluated in 74 consecutive patients (19 males and 55 females; aged 0–80 years). Sixty-three patients had congenital biliary dilatation and 11 did not. Type classification of congenital biliary dilatation was possible by ERCP alone in 45 patients (71%). The main causes of classification failure were previous bilio-enteric anastomosis and restriction of postural changes during ERCP due to general anesthesia in pediatric patients. Classification of anomalous junction was possible in 69 patients (93%). Technical difficulty in ERCP caused classification failure in 5 patients. Neoplastic lesions were found in 12 patients (16%) and all but 1 were correctly diagnosed by ERCP. We conclude that ERCP plays an important role in the preoperative diagnosis and type classification of anomalous pancreaticobiliary junction and congenital biliary dilatation.  相似文献   
87.
Abstract: We have evaluated the relationship between bone mass and mechanical properties of bone from male and female rats treated with YM175, a novel bisphosphonate, for 104 weeks. YM175 [disodium (cycloheptylamino) methylenediphosphonate monohydrate] was given via the drinking water at a concentration of 0, 0.005, 0.015, 0.05, or 0.15%. Since the mortality in the male 0.15% group exceeded the exclusion criteria (75%) at week 88, this group was omitted from the study. Mean daily intake of YM175 was 2.2-22.1 mg/kg for males and 3.6-104 mg/kg for females. After the treatment, mechanical properties and ash weight of the humerus were determined. In males, 0.015 and 0.05% of YM175 (6.6–22.1 mg/kg) significantly increased failure load of the midshaft. In females, failure load and stiffness of the midshaft tended to be increased by YM175 (up to 104 mg/kg). Furthermore, ultimate compressive load at the humeral metaphysis treated with the highest dose of YM175 was 2- or 3.5-fold greater than that of untreated male or female control. Ash weight of the humerus was increased dose-dependently and was positively correlated with failure load of the midshaft. These findings indicate that treatment for 2 years with YM175 increased bone mass and mechanical strength without blocking bone mineralization.  相似文献   
88.
Although the dry powder type inhaled steroids, such as Fluticasone Propionate Diskhaler (FP-DH), FP Diskus (FP-DK), Budesonide Turbuhaler (BUD-TH), are widely distributed in daily clinical fields, we clinicians are required to evaluate whether it is effectively inhibiting inflammation of distal airway or not. We also investigated the effect of Hydrofluoroalukan-beclomethasone dipropionate (HFA-BDP), a new type of inhaled steroid which forms super micro aerosol particles, in the distal small airway. METHOD: 85 patients with moderate asthma, who daily used dry powder type inhaled steroid for at least more than 6 months with stable asthmatic condition, were the subject of this study. All subjects underwent sputum induction with the inhalation of 10% of hypertonic saline solution for 15 min and eosinophil counts and eosinophil cationic protein (ECP) in individual induced sputum were measured. Then, patients who had eosinophils detected in their induced sputum changed their previously inhaled steroid to HFA-BDP inhalation (400 i.g./day). Their eosinophil counts and the values of eosinophil cationic protein (ECP), Eotaxin, RANTES and neutrophil elastase (PMN-E) in their induced sputum were also examined before and 4weeks after changing HFA-BDP inhalation. RESULT: Increased eosinophils were found in the induced sputum of 40.5% patients of the FP-DK group, 36.3% of the FP-DH group and 32.4% of the BUD-TH group, respectively. Compared with group of patients in which no sputum eosinophil were detected, the sputum ECP values, in which sputum eosinophils were detected, were significantly high. 4 weeks after changing to HFA-BDP inhalation, eosinophil counts, ECP, Eotaxin, RANTES and PMN-E in their induced sputum were decreased in every group. CONCLUSION: Compared with the ordinary dry powder type inhaled steroids, HFA-BDP can effectively diminish distal airway inflammation, suggesting the possibility that HFA-BDP can effectively reach to the distal small airway by forming super micro aerosol particles.  相似文献   
89.
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor.  相似文献   
90.
A 74-year-old woman suffered from progressive muscle atrophy and weakness of her arms since she was seventy two years old. Before referral to our department, she was diagnosed as having cervical spondylotic myeloradiculopathy and received spinal fusion. Though spinal decompression was successful, muscle weakness of her upper limbs were progressive even after the surgery. On admission, neurological examinations revealed marked atrophy and weakness of her bilateral upper limbs with absent deep tendon reflexes showing man-in-the-barrel syndrome. Her lower extremities had normal muscle strength, but fasciculations were seen in her all four limbs. Electrophysiologically, motor nerve conduction velocity was almost normal but the amplitude was remarkably decreased, conduction block was not detected, and electromyography showed neurogenic patterns on her all extremities. Spinal progressive musclar atrophy (SPMA) accompanied with Sj?gren's syndrome was the likely diagnosis. Because 50 kDa anti-neuronal antibodies were found in her serum, we assumed that anterior horn cells were impaired by an autoimmune mechanism. Thus we treated her with corticosteroid pulse therapy, plasma exchange (PE) and intravenous immunoglobulin infusion therapy (IVIG). Although steroid pulse therapy only had a minimal effect, PE and IVIG promoted a remarkable improvement on her weakness, and the effect lasted for about three months. This is the first case of SPMA with Sj?gren's syndrome which showed good response to PE and IVIG in the early course of the disease. We considered that some SPMA-like motor neuron syndrome accompanied with autoimmune features may require immunomodulating therapies.  相似文献   
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