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11.
A case of polycythemia vera complicated by chronic renal failure under maintenance hemodialysis requiring parathyroidectory (PTH) for secondary hyperparathyroidism (2° HPT) is reported. A 62 year old female presented with 75000 white blood cells (WBC)/μl, 703×104 red blood cells (RBC)/μl, 23×104 platelets (PLT)/μl, hyperuricemia and hypertension in 1970 and the diagnosis of polycythemia vera was made. Hemodialysis was started in October 1974 for chronic renal failure. Blood cells in peripheral blood rapidly decreased in number after the beginning of dialysis, reaching the level of 10000∼20000 WBC/μl, and 150∼250×104RBC/μl. In August 1988, marked bone resorption in X-ray picture and high serum alkaline phosphatase and parathyroid hormone (PTH) noted along with 17400 WBC/μl, 370×104RBC/μl and 35.9×104PLT/μl. After subtotal PTX removing 3.21g parathyroid gland, serum PTH rapidly fell. At 3 months after PTX, WBC rose to 23600/μl, RBC 372×104/μl and PLT 94.0×104/μl. At 6 months, WBC was to 31000/μl, RBC 429×104/μl and PLT 78.0×104/μl, suggesting an inhibitory action of PTH on not only RBC, but also WBC and PLT.  相似文献   
12.
13.
Biodegradable copolymers of L -lactic acid (L -LA) and DL -α-hydroxy acids with relatively low molecular weights, for example L -LA/DL -lactic acid (DL -LA), L -LA/DL -α-hydroxybutyric acid (DL -HBA), L -LA/DL -α-hydroxyisovaleric acid (DL -HIVA), and L -LA/DL -α-hydroxyisocaproic acid (DL -HICA), were synthesized by quantitative direct copolycondensation without catalysts at 200°C. The in vitro degradation, which was evaluated by measuring the weight loss of these copolymers in M/15 phosphate buffer solution (pH 7,2) without enzymes at 37°C, is strongly dependent on the kind and molecular weight of these copolymers, resulting in the formation of different degradation patterns such as parabola type (L -LA/DL -HBA system), linear type (L -LA/DL -LA system), and S type (L -LA/DL -HIVA and L -LA/DL -HICA systems).  相似文献   
14.
Limb-body wall complex is a malformation of body and limbs with craniofacial defects. We describe here the epidemiology of this complex using the population-based registry data in the Kanagawa Birth Defects Monitoring Program during the period 1982–1991. Eleven infants (11/428,599 births) with the complex were ascertained in the study. The incidence and spectrum of the defects observed in our cases were similar to those of other studies. The parental ages in the study group were not significantly different from those in the general population. No teratogenic agents and factors were identified in the present study. Most cases were diagnosed prenatally. © 1994 Wiley-Liss, Inc.  相似文献   
15.
Safety evaluation of surgical materials by cytotoxicity testing   总被引:2,自引:1,他引:1  
The cytotoxicity of three kinds of commercially available absorbable hemostats [oxidized cellulose (Surgicel, gauze and cotton types), microfibrillar collagen (Avitene), and cotton-type collagen (Integran)] and one adhesion barrier [sodium hyaluronate and carboxymethyl-cellulose membrane (Seprafilm)] were comparatively assessed by a colony assay using V79 cells and a minimum essential medium (MEM) elution assay in combination with a neutral red assay using L929 cells. Strong cytotoxicity was detected for Surgicel by both the MEM elution assay and the colony assay. For Avitene, both methods revealed weak cytotoxicity. For Seprafilm, no cytotoxicity was detected by the MEM elution assay, while a moderate degree of cytotoxicity was observed in the colony assay. For Integran cytotoxicity was not detected by either the MEM elution or the colony assay. The results of the different methods showed some inconsistency in terms of the degree of cytotoxicity of the materials. It is proposed that the combination of two or more sensitive cytotoxicity testing methods for the evaluation of biomaterials is necessary to avoid false-negative results for biomaterials at the preclinical stage. Furthermore, investigation of the correlation between the cytotoxicity and the extraction period of the surgical materials is helpful for predicting the effect of prolonged in vivo use of biomaterials on surrounding cells, tissues, and organs.  相似文献   
16.
OBJECTIVE: Repetitive paired-pulse transcranial magnetic stimulation (TMS) at I-wave periodicity has been shown to induce a motor-evoked potential (MEP) facilitation. We hypothesized that a greater enhancement of motor cortical excitability is provoked by increasing the number of pulses per train beyond those by paired-pulse stimulation (PPS). METHODS: We explored motor cortical excitability changes induced by repetitive application of trains of four monophasic magnetic pulses (quadro-pulse stimulation: QPS) at 1.5-ms intervals, repeated every 5s over the motor cortex projecting to the hand muscles. The aftereffects of QPS were evaluated with MEPs to a single-pulse TMS, motor threshold (MT), and responses to brain-stem stimulation. These effects were compared to those after PPS. To evaluate the QPS safety, we also studied the spread of excitation and after discharge using surface electromyograms (EMGs) of hand and arm muscles. RESULTS: Sizes of MEPs from the hand muscle were enhanced for longer than 75min after QPS; they reverted to the baseline at 90min. Responses to brain-stem stimulation from the hand muscle and cortical MEPs from the forearm muscle were unchanged after QPS over the hand motor area. MT was unaffected by QPS. No spreads of excitation were detected after QPS. The appearance rate of after discharges during QPS was not different from that during sham stimulation. CONCLUSIONS: Results show that QPS can safely induce long-lasting, topographically specific enhancement of motor cortical excitability. SIGNIFICANCE: QPS is more effective than PPS for inducing motor cortical plasticity.  相似文献   
17.
TNFalpha plays an important role as an inflammatory mediator in both several autoimmune diseases and multiple sclerosis. Anti-TNFalpha antibody has been widely used to treat rheumatoid arthritis and Crohn's disease. On the. other hand, anti-TNFalpha antibody treatment increased recurrence rate in clinical trials for multiple sclerosis. We report a patient with rheumatoid arthritis without past history of any neurological disorders, who developed diplopia, ataxia, and visual agnosia specific to line drawing in the course of anti-TNFalpha antibody treatment. MRI studies detected multiple demyelinating lesions in the cerebral white matter and brainstem. The present case indicates that careful observation of neurological symptoms is important in the course of anti-TNFalpha antibody treatment, even in patients without past history of demyelinating diseases.  相似文献   
18.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
19.
OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms.  相似文献   
20.
We report herein the case of a 70-year-old man in whom a chest wall implantation of adenocarcinoma of the lung at the drainage tube site was found 4 months after a right lower lobectomy with mediastinal lymph node dissection had been performed for adenocarcinoma of the right lower lobe. The lesion was successfully treated by tumor extirpation. We believe that tumor seeding to the chest wall occurred at the time of thoracotomy. To prevent such tumor seeding, the pleural cavity should be washed out routinely with a massive volume of physiological saline solution prior to closure of the chest wall.  相似文献   
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