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991.
992.
A proteasome inhibitor with a new molecular target (PS-341: bortezomib) was recently developed, and its efficacy in the treatment of refractory multiple myeloma has been reported in the United States. Here, we present a 54-year-old Japanese male patient with refractory multiple myeloma resistant to thalidomide. In 1998, the patient was diagnosed as having multiple myeloma (IgG-kappa) and underwent chemotherapy, autologous hematopoietic cell transplantation and interferon therapy, but the disease recurred. In December 2002, thalidomide and high-dose dexamethasone therapy was initiated, and while this combination therapy was effective at first, the multiple myeloma became unresponsive. On 23 June 2003, bortezomib therapy with the following regime was therefore started: 2.2 mg (1.3 mg/m2) of bortezomib was injected intravenously on days 1, 4, 8 and 11, and after a one-week break, another cycle was performed. Starting on day 8 of the administration, the serum total protein, IgG, serum calcium and LDH levels decreased rapidly, and after day 45 of the administration, blood transfusion was no longer needed. Since this is the first report of the use of bortezomib in the treatment of refractory multiple myeloma in Japan, further monitoring of this patient will provide extremely valuable information for developing a therapy against this disease.  相似文献   
993.
The effects of bradykinin on the regulatory mechanisms of prostacyclin synthesis in endothelial cells were investigated in association with intracellular Ca(2+) kinetics, cytosolic phospholipase A(2) (cPLA(2)) activity, and mRNA expression of cPLA(2) and prostaglandin H synthase (PGHS) isoforms. Bradykinin enhanced prostacyclin release from endothelial cells time-dependently, but pretreatment with EGTA H-7 or HOE 140 inhibited bradykinin-induced prostacyclin release. Bradykinin increased both the influx of extracellular Ca(2+) and Ca(2+) release from the intracellular Ca(2+) storage sites. These reactions occurred within 5 minutes after bradykinin stimulation. Within 15 minutes, bradykinin activated cPLA(2) to 1.3-fold the control level. The constitutive expressions of mRNA of cPLA(2), PGHS-1, and PGHS-2 was 87, 562, and 47 amol/microg RNA, respectively. With the stimulation of bradykinin, cPLA(2) mRNA increased to 746 amol/microg RNA in 15 minutes, PGHS-1 mRNA increased to 10 608 amol/microg RNA, and PGHS-2 mRNA increased to 22 400 amol/microg RNA in 180 minutes. Pretreatment with cycloheximide superinduced cPLA(2) and PGHS-2 mRNA expression but almost completely inhibited PGHS-1. Pretreatment with EGTA had effects similar to pretreatment with cycloheximide in the case of cPLA(2) and PGHS-1 but did not affect PGHS-2. These findings suggest that the elevation of cPLA(2) activity caused by the increase of intracellular Ca(2+) concentration is important in the early phase of bradykinin-induced prostacyclin synthesis and that the mechanisms regulating cPLA(2) are different from those regulating PGHS isoforms in endothelial cells.  相似文献   
994.
This paper reports four digital style design systems to construct a sophisticated shape from a concept or a rough sketch. First one is a system to automatically construct a 3D digital model form key words expressing the product concept. Second one is a system to automatically construct the 3D digital model from a rough sketch drown by a designer. Third one is a system to automatically sophisticate a 3D digital model according to the high light lines indicated by a designer. Fourth one is a system to sophisticate a 3D digital model by forming characteristic lines indicated by a designer.  相似文献   
995.
996.
The present study was undertaken to evaluate p53 gene mutation as a prognostic factor in patients with colorectal cancer. Nonisotopic RNase cleavage assay (NIRCA), recently used for detecting gene mutations, was employed to detect p53 gene mutations in this study. In 15 samples of colorectal tumors, NIRCA was confirmed to be simple, accurate, and thus useful for clinical use, compared with polymerase chain reaction single-strand conformational polymorphism (PCR-SSCP). In another group of 79 cases of colorectal cancer analyzed for p53 gene mutation by using NIRCA, mutations were detected in 58 of 79 (73.4%) cases. Multivariate Cox proportional-hazards analysis showed that p53 gene mutation was a significant prognostic factor in patients with colorectal cancer. Our results showed that NIRCA is a simple and sensitive method, and thus useful for genetic screening of colorectal cancer. Furthermore, our results showed that p53 gene mutation is an independent predictor of poor prognosis in colorectal cancers.  相似文献   
997.
A forty-year-old man was admitted to our hospital because of dizziness, palpitations and an oppressive feeling in the precordium. Physical examination was normal. A chest roentgenogram revealed mild cardiomegaly and the electrocardiogram showed ventricular tachycardia of a left bundle branch block configuration which was terminated by the intravenous injection of procainamide. During sinus rhythm the electrocardiogram showed incomplete right bundle branch block, PQ prolongation and inverted T waves in leads V1 through V3. Two-dimensional echocardiography revealed only moderate right ventricular dilatation. Right ventricular angiography showed severe right ventricular dilatation and hypokinesis of the right ventricular apex and pulmonary artery infundibulum. From these characteristics signs we concluded that this adult patient had arrhythmogenic right ventricular dysplasia (ARVD), suggesting that this condition is not confined to children but may occur in adults as well.  相似文献   
998.
Barrett's esophagus(BE) is a precursor of esophageal adenocarcinoma and is associated with gastroesophageal reflux disease, which is often preceded by a hiatal hernia. We describe a case of esophageal adenocarcinoma arising in long-segment BE(LSBE) associated with a hiatal hernia that was successfully treated with a laparoscopic transhiatal approach(LTHA) without thoracotomy. The patient was a 42-year-old male who had previously undergone laryngectomy and tracheal separation to avoid repeated aspiration pneumonitis. An ulcerative lesion was found in a hiatal hernia by endoscopy and superficial esophageal cancer was also detected in the lower thoracic esophagus. The histopathological diagnosis of biopsy samples from both lesions was adenocarcinoma. There were difficulties with the thoracic approach because the patient had severe kyphosis and muscular contractures from cerebral palsy. Therefore, we performed subtotal esophagectomy by LTHA without thoracotomy. Using hand-assisted laparoscopic surgery, the esophageal hiatus was divided and carbon dioxide was introduced into the mediastinum. A hernial sac was identified on the cranial side of the right crus of the diaphragm and carefully separated from the surrounding tissues. Abruption of the thoracic esophagus was performed up to the level of thearch of the azygos vein via LTHA. A cervical incision was made in the left side of the permanent tracheal stoma, the cervical esophagus was divided, and gastric tube reconstruction was performed via a posterior mediastinal route. The operative time was 175 min, and there was 61 m L of intra-operative bleeding. A histopathological examination revealed superficial adenocarcinoma in LSBE. Our surgical procedure provided a good surgical view and can be safely applied to patients with a hiatal hernia and kyphosis.  相似文献   
999.

Background

Peritoneal lavage with distilled water has been performed during colorectal cancer surgery. This study investigated the cytocidal effects of hypotonic shock in vitro and in vivo in colorectal cancer cells.

Methods

Three human colorectal cancer cell lines, DLD1, HT29, and CACO2, were exposed to distilled water, and morphological changes were observed under a differential interference contrast microscope connected to a high-speed digital video camera. Cell volume changes were assessed using a high-resolution flow cytometer. Re-incubation experiments were performed to investigate the cytocidal effects of distilled water. In the in vivo experiment, cancer cells after hypotonic shock were injected intraperitoneally into mice and the degree of established peritoneal metastasis was subsequently evaluated. The effects of the blockade of Cl? channels on these cells during hypotonic shock were also analyzed.

Results

Morphological observations revealed a rapid cell swelling followed by cell rupture. Measurements of cell volume changes showed that mild hypotonic shock induced regulatory volume decrease (RVD) while severe hypotonic shock broke cells into fragments. Re-incubation experiments demonstrated the cytocidal effects of hypotonicity. In vivo experiments revealed the absence of peritoneal dissemination in mice in the distilled water group, and its presence in all mice in the control group. The blockade of Cl? channels increased cell volume by inhibiting RVD and enhanced cytocidal effects during mild hypotonic shock.

Conclusions

These results clearly support the efficacy of peritoneal lavage with distilled water during colorectal cancer surgery and suggest that regulating of Cl? transport may enhance the cytocidal effects of hypotonic shock.
  相似文献   
1000.
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