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991.
Comparative Hemolysis Study of Clinically Available Centrifugal Pumps   总被引:1,自引:0,他引:1  
Abstract
Centrifugal pumps have become important devices for cardiopulmonary bypass and circulatory assistance. Five types of centrifugal pumps are clinically available in Japan. To evaluate the blood trauma caused by centrifugal pumps, a comparative hemolysis study was performed under identical conditions. In vitro hemolysis test circuits were constructed to operate the BioMedicus BP-80 (Medtronic, BioMedicus), Sams Delphin (Sarns/3M Healthcare), Isoflow (St. Jude Medical [SJM]), HPM-15 (Nikkiso), and Capiox CX-SP45 (Terumo). The hemolysis test loop consisted of two 1.5 m lengths of polyvinyl chloride tubing with a 3/8 -inch internal diameter, a reservoir with a sampling port, and a pump head. All pumps were set to flow at 6 L/min against the total pressure head of 120 mm Hg. Experiments were conducted simultaneously for 6 h at room temperature (21oC) with fresh bovine blood. Blood samples for plasma-free hemoglobin testing were taken, and the change in temperature at the pump outlet port was measured during the experiment. The mean pump rotational speeds were 1,570, 1,374, 1,438, 1,944, and 1,296 rpm, and the normalized indexes of hemolysis were 0.00070, 0.00745, 0.00096, 0.00066, 0.00090 g/100 L for the BP-80, Sarns, SJM, Nikkiso, and Terumo pumps, respectively. The change in temperature at the pump outlet port was the least for the Nikkiso pump (1.8oC) and the most with the SJM pump (3.8oC). This study showed that there is no relationship between the pump rotational speed (rpm) and the normalized index of hemolysis in 5 types of centrifugal pumps. The pump design and number of impellers could be more notable factors in blood damage.  相似文献   
992.
Background: The number of metastatic regional lymph nodes determines the new pN categories in the 5th edition of the TNM classification.

Study Design: Our retrospective study was conducted to compare the new method of defining lymph node status with the conventional classification, consisting of the anatomic extent of lymph node metastases, a well-established prognostic factor. The study was based on clinical data for 493 patients with gastric carcinomas who underwent potentially curative operations and had histologically confirmed nodal metastases. These patients were stratified into 1) n categories according to the Japanese Classification of Gastric Carcinoma, 2) the new pN categories, and 3) the pN categories determined by the number of metastatic perigastric nodes resected by standard D1 gastrectomy. Survival data were analyzed for each group.

Results: The number of metastatic nodes after D2 lymphadenectomy reflected prognosis well and was shown by multivariate analysis to be a strong independent prognostic factor. When the classification was performed limited to the metastatic perigastric nodes, stage migration was evident, but the variable remained competent as a prognostic indicator.

Conclusions: The number of metastatic nodes is a promising determinant in the new international stage classification.  相似文献   

993.
r = 0.916, n = 5, p = 0.0288) for the mucosal carcinomas, but their relation was not significant for the submucosal carcinomas ( r = 0.677, n = 5, p = 0.2091). By analyzing the 344 differentiated mucosal carcinomas, moderately differentiated tubular adenocarcinomas were seen to be frequently less differentiated at resection. The histology of the biopsy specimens from mucosal carcinoma of the stomach grossly satisfies one of the criteria for limited surgery, but moderately differentiated adenocarcinoma may not be suitable for this treatment.  相似文献   
994.
PURPOSE: Recently, MMP-7 and MMP-3 have been found to play a crucial role in the natural resorption process of herniated discs. We therefore examined the role of these recombinant human matrix metalloproteinases (rh MMPs) in the treatment of herniated discs. METHODS: (a) Surgical samples of herniated disc were cultured in the presence or absence of rh MMPs, and wet weight was measured 24h later. (b) The rh MMPs were administered into normal rabbit intervertebral discs, and after 1 week spine samples were stained with Safranin O. (c) The rh MMPs were administered into canine herniated discs in vivo. Myelography and MRI were performed prior to and 1 week after administration. Spine samples were examined histologically. Whole disc tissue was collected, total protein was extracted, and Western blot analysis was performed. RESULTS: (a) Proteoglycan degradation was found in MMP-7, MMP-3, and chymopapain-treated samples. MMP-7 and chymopapain-treated samples displayed a significant loss in wet weight (p<0.01). (b) Normal disc tissues after administration of rh MMP-7, MMP-3, and chymopapain showed an extensive loss of Safranin O staining. (c) The rh MMP-7-treated discs had a marked decrease in protruded herniation by MRI. Herniated discs after administration of MMP-7 and chymopapain showed a significant decrease in protruded mass 7 days after administration compared with saline-treated discs when evaluated by myelography (p<0.01). The rh MMP-7-treated discs displayed a clear loss of Safranin O staining in the nucleus pulposus. Proteoglycan expression was barely detectable in disc tissues after MMP-7 administration, whereas obvious expression was obtained in saline-treated or untreated disc tissues. CONCLUSIONS: Exposure to rh MMP-7 resulted in promising proteoglycan loss in human surgical samples, normal rabbit intervertebral discs, and natural canine herniated discs. Administration of rh MMP-7 may facilitate the resorption process of herniated discs.  相似文献   
995.
To determine whether there are disturbances of hippocampal volume asymmetry in schizophrenic patients, we obtained contiguous, I-mm-thick magnetic resonance images in 28 males with chronic schizophrenia and in 28 age-matched healthy males. The schizophrenic patients showed a bilateral reduction in volume of the hippocampal formation (HF; left 7.0%; right 8.7%). This reduction was significantly associated with the severity of disorganization syndrome (P < 0.0005). A significant asymmetry in the HF volume was found in the control subjects (P = 0.006), but not in the patients (P = 0.40). There was a significant positive correlation between the asymmetry index and the patient’s age at the onset of schizophrenia (r = 0.46,P = 0.01). Results indicate that a disturbance in the normal asymmetry of the HF may be a characteristic in schizophrenia, particularly in patients with an early onset of the illness.  相似文献   
996.
Background: Rush immunotherapy (RIT) has been shown to be effective in allergic asthma. Objective: We investigated the mechanisms of RIT on the basis of cytokine production by T-cell lines and airway inflammation and responsiveness. Methods: Subjects were 8 patients with house dust mite–allergic asthma treated with dust mite extract RIT for 6 months and 6 RIT-untreated control patients. IL-5 production by Dermatophagoides farinae –specific T-cell lines, eosinophil percentages, and eosinophil cationic protein (ECP) in induced sputum and airway responsiveness to allergen and histamine were evaluated before and after treatment. Changes in eosinophil percentages and ECP in induced sputum and responsiveness to histamine 24 hours after allergen inhalation were also studied. Results: After 6 months of RIT, percentages of total eosinophils (43.0% ± 6.90% to 16.8% ± 2.48%; P < .01), percentages of EG2+ eosinophils (32.6% ± 6.39% to 19.7% ± 4.68%; P < .01) and ECP (362.7 ± 125.3 ng/mL to 26.2 ± 5.15 ng/mL; P < .05) decreased in induced sputum, and IL-5 production by T-cell lines decreased (617 ± 93.2 pg/mL to 200.0 ± 34.1 pg/mL; P < .01). RIT decreased both early- and late-phase bronchoconstriction (early phase: 33.2% ± 3.46% to 25.4% ± 1.42%; P < .03; late phase: 16.2% ± 3.52% to 6.2% ± 1.96%; P < .03) and suppressed increases in the percentages of total (61.8% ± 4.89% to 42.0% ± 4.67%; P < .01) and EG2-positive eosinophils (55.54% ± 7.21% to 36.5% ± 6.43%; P < .01) and ECP (685.6 ± 217.0 ng/mL to 85.4 ± 23.4 ng/mL; P < .05) in induced sputum after allergen inhalation. RIT also decreased airway responsiveness to dust mite (1:303.7 ± 123.7 wt/vol to 1:65.0 ± 13.2 wt/vol; P < .03) and to histamine before (397.1 ± 206.9 μg/mL to 1391.3 ± 283.3 μg/mL; P < .03) and after allergen inhalation (139.2 ± 36.5 μg/mL to 629.1 ± 196.3 μg/mL; P < .03). Conclusion: RIT decreases airway inflammation and airway hyperresponsiveness before and after bronchial provocation with allergen, possibly by inhibiting both allergen-specific T-cell– and mast cell-dependent pathways. RIT is an effective antiinflammatory treatment in allergic asthma. (J Allergy Clin Immunol 1998;102:927-34.)  相似文献   
997.
We report an unusual case of intramuscular venous malformation with calcifications that presented with features of involvement of the ulnar nerve.  相似文献   
998.
Idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome, GS) is a relatively common congenital hyperbilirubinemia occurring in 3-7% of the world's population. It has been recognized as a benign familial condition in which hyperbilirubinemia occurs in the absence of structural liver disease or hemolysis, and the plasma concentration of conjugated bilirubin is normal. Recently, it was reported that unconjugated bilirubin exhibited neurotoxicity in the developing nervous system. The 'neurodevelopmental hypothesis' of schizophrenia proposes that an as yet unidentified event occurs in utero or during early postnatal life. We have observed that patients suffering from schizophrenia frequently present an increased unconjugated bilirubin plasma concentration when admitted to the hospital. Therefore, we noticed a relation between unconjugated bilirubin and the etiology of and vulnerability to schizophrenia. Our reported findings suggest that there are significant biological and clinical character differences between schizophrenic patients with and without GS. From the viewpoint of the heterogeneity of schizophrenia, there may be a poor outcome for the subtype of schizophrenia with GS.  相似文献   
999.
True aneurysm of the posterior tibial artery is very rare. A 69-year-old woman presented with a pulsatile painful mass of the right lower leg.  相似文献   
1000.
A 69-year-old Japanese man undergoing total gastrectomy for multiple gastric ulcers at age 46 was found endoacopically to have multiple esophageal cancers in the upper, mid, and lower esophagus. Esophageal mucosa associated with tumors was replaced with columnar epithelium. He underwent total esophagectomy combined with laryngectomy, pharyngectomy, and lymph node dissection using the large bowel for reconstruction. The resected esophagus had multiple cancers, including well-differentiated adenocarcinoma, poorly differentiated adenocarcinoma, and small-cell carcinoma. Barrett's mucosa consisted mainly of specialized columnar epithelium while both junctional and fundic Barrett's epithelium was observed partially but not clearly. This case is indicative of the high and totipotential carcinogenetic risk of Barrett's epithelium and the relationship between duodenal content reflux and esophageal carcinogenesis after total gastrectomy.  相似文献   
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