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981.
A 53-year-old man with mitochondrial disease underwent gastrectomy because of gastric cancer. Three days after the surgery, he developed severe hyponatremia (Na, 106 mmol·l?1) together with hypovolemic shock and lactic acidosis. Despite the hyponatremia, his urine sodium concentration was high, suggesting renal salt wasting. Although mitochondrial diseases are not common and hyponatremia in patients with these diseases is not well known, clinicians should pay close attention to serum sodium levels and maintain them properly.  相似文献   
982.
Fifty-three tumor specimens, including thirty-one stomach and seven esophageal cancers, were examined to determine the individual tumor sensitivity to chemotherapeutic agents. Using the subrenal capsule assay (SRC assay), tumor specimens were implanted under the renal capsule of male, 8 week old ddY mice, after cutting the tissues into 1.5 mm cubed fragments. Following the implantations, chemotherapeutic agents were injected daily for 3 days and the relative variations of tumor weights were calculated. An 84.9 per cent of the total evaluability rate was obtained and implanted tumor specimens responsed to chemotherapeutic agents in 26.7 per cent. The correlation rate between tumor sensitivity in SRC assay and clinical responses was obtained in 72.9 per cent. The predictive accuracy rate of the clinical responses was 50.0 per cent, while 100 per cent of the prediction rate of clinical resistance was obtained. With regard to upper gastro-intestinal cancers, 83.9 per cent of the evaluability rate and 18.2 per cent of response rate in SRC assay were obtained. These results indicate that this assay is equivalent to other procedures for predicting individual tumor sensitivity.  相似文献   
983.
The present study investigated the mechanism by which the disposition of insulin is altered in streptozotocin (STZ)-treated diabetic rats as compared with 48-hr-fasted normal (control) rats. It was shown by an indocyanine green infusion method that the hepatic plasma flow rate (Q H) in diabetic rats (1.64 ml/min/g liver) is significantly higher than that in control rats (0.982 ml/min/g liver). The portal injection technique revealed that the unidirectional clearance (CLon), which represents the binding of A14-125 I-insulin to surface receptors in the liver, is significantly elevated in diabetic rats, suggesting an increase in the surface receptor number R T), i.e., up-regulation in the liver. In both control and diabetic rats, the total-body clearance (CLtot) and steady-state volume of distribution (Vd ss) of labeled insulin decreased significantly with a simultaneous injection of unlabeled insulin (8 U/kg), confirming that the disposition of insulin is affected largely by specific, saturable receptor-mediated processes. The CLtot and Vd ss increased significantly in diabetic rats, while nonspecific portions of these parameters were not changed. From the increases in CLtot (80%) and Q H (67%) in diabetic rats, a pharmacokinetic analysis has revealed a 40% increase in the hepatic intrinsic clearance (CLint sp) of A14-125 I-insulin via a specific mechanism in diabetic rats. In conclusion, we have provided in vivo evidence for a small increase in CLint sp of insulin in STZ-diabetic rats compared with control rats, which may be caused by an increase in the surface receptor number in the livers of diabetic rats.  相似文献   
984.
Summary The normal development of the spinal cord from the fetal period to infancy was studied by ultrasonography (US) with a 7.5 MHz transducer. Longitudinal and transverse sections of the spinal cord were clearly observed. The sagittal and transverse diameters of the spinal cord increased with age. In order to evaluate disorders of the spinal cord precisely, it is necessary to clarify the normal features as well as the normal development of the spinal canal and cord, and the surrounding structures. US with such a high frequency transducer will be the most suitable for this purpose.  相似文献   
985.
We here report the case of an 18-year-old man with a giant yolk sac tumor that is resected under percutaneous cardiopulmonary support (PCPS). Because this patient had severe dyspea when he lay in a supine position, we resected the tumor. We used PCPS during the operation for the induction and maintenance of ventilation because his trachea and left main bronchus were collapsed by the tumor. Also, we used a vacuum aspiration device that is commonly used for facilitating difficult vaginal deliveries. We propose that several devices, such as a PCPS and vacuum aspiration device, are useful for the operation of a mediastinal tumor with dyspnea.  相似文献   
986.
987.
Co-incubation of human leukemia cell lines with naturally occurring nucleobases (hypoxanthine or adenine) significantly prevented the cytotoxic activity of 6-thiopurines. Extracellular hypoxanthine decreased the transport of 6-mercaptopurine into cells, but adenine had no significant effect. However, intracellular thioinosine monophosphate accumulation in the presence of 10 microM, 6-mercaptopurine was reduced to below 1% or 10% of that of the controls when 50 microM hypoxanthine or adenine was added, respectively. Finally, in adenine phosphoribosyl transferase deficient mutants, adenine provided no protective effect against 6-thiopurines, whereas hypoxanthine retained its modulating activity. These data suggest that the nucleobases compete with 6-thiopurines for the ribose-phosphate donor, 5'-phosphoribosyl-1-pyrophosphate, thus preventing the formation of active metabolites of 6-thiopurines.  相似文献   
988.
Pseudomyxoma peritonei (PMP) is a rare clinical entity in which a diffuse collection of intraperitoneal gelatinous fluid is associated with gelatinous implants on the peritoneal surfaces and omentum. Hematogenic or lymphatic metastasis is extremely rare. In addition, an inguinal mass as an initial presentation is also relatively rare. This is a case report of a PMP patient who had splenic metastasis and showed an inguinal tumor as an initial presentation. A 59-year-old female patient, who had undergone bilateral oophorectomy because of a ruptured ovarian mucinous tumor of boderline malignancy 12 years previously, presented a presumptive diagnosis of a left inguinal irreducible hernia. Computed tomography revealed a low density mass in the pelvic cavity and in the inguinal lesion, as well as in the spleen without any diseases around the organ. The preoperative serum carcinoembryonic antigen (CEA) level was elevated. The patient underwent a resection of gelatinous tumor in the pelvic cavity, splenectomy, and appendectomy, as well as left inguinal herniorrhaphy. Histological examinations revealed a splenic metastasis of PMP originating from the ovarian low-grade mucinous tumor. She received postoperative intraperitoneal lavage as well as chemotherapy, and has survived for over 7 years postoperatively without any evidence of recurrence, as confirmed by repeated follow-up CT examinations and CEA determination. Splenic metastasis of PMP is extremely rare; this represents only the third reported case of its kind in the literature. Furthermore, it should be noted that an inguinal tumor can sometimes be an initial presentation of PMP.  相似文献   
989.
Orthodontic therapy is known to have an aggravating effect on the progression of destructive periodontitis if oral hygiene is not maintained. However, it is largely unknown how active periodontitis affects the velocity of orthodontic tooth movement. In this study, we examined the effect of periodontal inflammation on orthodontic tooth movement using a mouse model. Orthodontic force was applied on the maxillary first molar of mice, with or without ligature wire to induce experimental periodontitis. The distance moved by the first molar was significantly reduced by the ligature-induced experimental periodontitis. Tartrate-resistant acid phosphatase staining revealed that the number of osteoclasts present during orthodontic treatment was lower in the pressure zone of alveolar bone in the presence of periodontal inflammation. Consistently, the expression level of receptor activator of nuclear factor-κB ligand (RANKL) in the pressure zone was decreased in the ligature group. By contrast, experimental periodontitis increased the expression of cyclooxygenase-2 mRNA in the periodontal tissues, while in vitro treatment with prostaglandin E2 decreased extracellular signal-regulated kinase phosphorylation and RANKL expression induced by mechanical stress in osteoblasts. Taken together, these results suggest that the orthodontic force-induced osteoclastogenesis in alveolar bone was inhibited by the accompanying periodontal inflammation, at least partly through prostaglandin E2, resulting in reduced orthodontic tooth movement.  相似文献   
990.
We compared a new tumor marker NCC-ST-439 (ST-439) with CA 15-3, CEA and TPA for its clinical usefulness in 600 patients with breast cancer (81, primary; 49, recurrent; 470, non-recurrent), and confirmed the following results. The sensitivity of ST-439 (41.5%) was significantly higher (p less than 0.05) than that of CA 15-3 (26.2%), CEA (28.5%) and TPA (26.9%). The specificity of ST-439 (84.5%), however, was considerably lower (p less than 0.01) than these other three markers. In primary cases, the positive rate of ST 439 (34.6%) was significantly higher (p less than 0.05) than that of the other markers, and was remarkable in the early stage. As to the positive rate at the various metastatic sites, there were a few differences among these four markers. Because of no significant correlation among these markers, combination assay with ST-439, CA 15-3 and CEA showed an excellent sensitivity (57.7%). These results suggest that ST-439 is a useful tumor marker not only in monitoring the recurrence, but also in the diagnosis of primary cancer.  相似文献   
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