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51.
Novel magnetic resonance angiography stage grading for moyamoya disease   总被引:1,自引:0,他引:1  
BACKGROUND: Magnetic resonance angiography (MRA) has been acknowledged as a noninvasive diagnostic modality for moyamoya disease. However, in terms of staging of moyamoya disease, conventional angiography is still the gold standard. Therefore, the purpose of this study was to establish MRA grades for moyamoya disease as an alternative to conventional angiography. METHODS: Twenty-two patients (44 sides) with moyamoya disease diagnosed by conventional angiography were evaluated by MRA during the past 5 years. MRA scores were assigned based on the severity of occlusive changes of the internal carotid artery, the horizontal portion of the middle cerebral artery, the anterior and the posterior cerebral arteries and the signals of the distal branches of these arteries. Total points ranged from 0 (normal) to 10 (most severe). RESULTS: MRA scores (0-10) were significantly consistent with the conventional angiographic staging. Four grades based on this novel MRA scores correlated well with Suzuki's stages, with high sensitivity and specificity. CONCLUSIONS: These novel MRA grades can be a reliable alternative to conventional staging. By employing these novel MRA grades, the use of conventional angiography can be avoided for the purpose of evaluation of the stages of moyamoya disease.  相似文献   
52.
The purpose of this study was to build a visualization technique of the femorotibial contact in fixed-bearing total knee arthroplasty (TKA) using X-ray fluoroscopy, and to apply this technique to a TKA patient during dynamic motion. In vivo kinametcis of the metallic knee implant was determined using a 2D/3D registration technique, which uses computer assisted design (CAD) model of the implant to estimate the 3D pose of radiopaque metallic femoral and tibial components from a single-plane fluoroscopic image. In fixed-bearing TKA, a 3D pose of radiolucent tibial polyethylene insert can be determined from the estimated pose of the tibial component. To visualize femorotibial contact, the proximity between surfaces of femoral component and tibial insert was calculated, and mapped onto the insert surface model. For the clinical application, dynamic states of contact on the tibial insert were observed including axial rotation and unilateral loading during knee flexion, and post-cam contact of posterior stabilized TKA. The present technique provided us new information and enabled us to better understand the relationship between in vivo knee kinematics and articular shape of the implant.  相似文献   
53.

Purpose

Abnormalities in esophageal motor function underlie various symptoms in the pediatric population. Manometry remains an important tool for studying esophageal motor function, whereas its analyses have been conducted with considerable subjective interpretation. The usefulness of videomanometry with topographic analysis was examined in the current study.

Methods

Videomanometry was conducted in 5 patients with primary gastroesophageal reflux disease (GERD), 4 with postoperative esophageal atresia (EA), 1 with congenital esophageal stenosis (CES), and 1 with diffuse esophageal spasms (DES). Digitized videofluoroscopic images were recorded synchronously with manometric digital data in a personal computer. Manometric analysis was conducted with a view of concurrent esophageal contour and bolus transit.

Results

Primary GERD patients showed esophageal flow proceeding into the stomach during peristaltic contractions recorded manometrically, whereas patients with EA/CES frequently showed impaired esophageal transit during defective esophageal peristaltic contractions. A characteristic corkscrew appearance and esophageal flow in a to-and-fro fashion were seen with high-amplitude synchronous esophageal contractions in a DES patient. The topographic analysis showed distinctive images characteristic of each pathological condition.

Conclusions

Videomanometry is helpful in interpreting manometric data by analyzing concurrent fluoroscopic images. Topographic analyses provide characteristic images reflecting motor abnormalities in pediatric esophageal disease.  相似文献   
54.

Purpose

Children with neurologic and neuromuscular handicaps frequently have various symptoms related to gastroesophageal reflux (GER) disease. The long-term efficacy of antireflux surgery remains controversial in such children with GER. The clinical results of such patients who underwent laparoscopic fundoplication were examined in the current study.

Methods

Between 1997 and 2003, laparoscopic fundoplication was performed in 56 handicapped children (mean age, 6 years), and gastrostomy was performed concurrently in 52. The main symptoms were emesis/hematemesis in 40 and respiratory symptoms, including repeated respiratory infection and distress, in 31.

Results

There were no severe postoperative complications or operative mortality. Emesis/hematemesis was controlled adequately in those without recurrence. Respiratory symptoms were controlled unsuccessfully in 16 patients (52%), 8 of whom required further respiratory care including nasal airway tube, tracheostomy, and laryngotracheal separation. Recurrence of GER disease occurred in 10 patients, 7 of whom underwent a second Nissen fundoplication successfully. Thirteen died within the median follow-up period of 14 months.

Conclusions

Laparoscopic fundoplication is effective in controlling emesis/hematemesis, but its efficacy is limited in terms of respiratory problems in handicapped children. Further refinements in diagnostic and treatment strategies are mandatory to improve the quality of life in such patients.  相似文献   
55.
BACKGROUND/AIM: Intima media thickness (IMT) and stiffness of the carotid arteries is related to coronary artery disease, and chronic renal failure patients are at high risk for such diseases. An oral adsorbent, AST-120 (Kremezin; Kureha Chemical Industry, Tokyo, Japan), can delay the progression of chronic renal failure in undialyzed uremic patients. The aim of the present study was to determine whether AST-120 affects carotid artery IMT and pulse wave velocity (PWV) in patients with chronic renal failure not undergoing dialysis. METHODS: Fifty patients with non-diabetic chronic renal failure were randomly divided into two groups: 30 patients (18 men and 12 women; mean age 53.5 years; mean serum creatinine 3.2 mg/dl) who were given AST-120 (6.0 g/day) and 20 patients (12 men and 8 women; mean age 52.0 years; mean serum creatinine 3.5 mg/dl) who were not given AST-120. Thirty healthy age-matched subjects (18 men and 12 women; mean age 51.5 years; mean serum creatinine 0.9 mg/dl) were also included. The treatment period was 24 months. IMT and arterial stiffness were measured before and after treatment. RESULTS: The slope of the reciprocal serum creatinine concentration over time became significantly less steep in the AST-120 group than in the non-AST-120 group (p < 0.001). Before treatment, carotid artery IMT differed little between the AST-120 group (0.90 +/- 0.22 mm) and the non-AST-120 group (0.88 +/- 0.20 mm). IMT in these two groups was significantly greater than IMT in the control group (0.64 +/- 0.14 mm) (p < 0.01). Carotid IMT in the AST-120 group decreased slightly but not significantly to 0.84 +/- 0.20 mm after 12 months and then significantly after 24 months to 0.78 +/- 0.18 mm (p < 0.05). Carotid IMT in the non-AST group showed little change throughout the experimental period. PWV differed little between the AST-120 group (1,980 +/- 330 cm/s) and the non-AST group (1,940 +/- 360 cm/s) before treatment. PWV values in these two groups were significantly greater than PWV in the control group (1,280 +/- 240 cm/s) (p < 0.01). After 12 and 24 months, PWV in the AST-120 group decreased significantly to 1,840 +/- 280 cm/s (p < 0.05) and to 1,780 +/- 260 cm/s (p < 0.05), respectively; however, PWV in the non-AST group showed a slight increase during the experimental period. CONCLUSION: The data suggest that AST-120 may reduce arterial stiffness and IMT in non-diabetic chronic renal failure patients before dialysis.  相似文献   
56.
Amlodipine, a dihydropyridine Ca(2+) channel blocker, is reported to inhibit proliferation of human epidermoid carcinoma A431 cells, and specifically attenuates Ca(2+) responses evoked by thapsigargin, an inhibitor of endoplasmic reticulum Ca(2+)-ATPases. In this study, we further examined the possible mechanism of the antiproliferative action of amlodipine and its antitumor effect on A431 xenografts in nude mice. Amlodipine reduced BrdU incorporation into nucleic acids in serum-starved A431 cells, and the reduction was diminished by uridine 5'-triphosphate (UTP), a phospholipase C (PLC)-linked agonist. Fluorometric measurement of intracellular free Ca(2+) concentration revealed that amlodipine blunted the UTP-induced Ca(2+) release from the internal Ca(2+) stores and consequently Ca(2+) influx through Ca(2+)-permeable channels on the plasma membrane. Although amlodipine alone caused Ca(2+) release from thapsigargin-sensitive Ca(2+) stores, such an effect was not reproduced by other dihydropyridine Ca(2+) channel blockers, including nicardipine and nimodipine, despite their antiproliferative effects in the cells. Daily intraperitoneal administration of amlodipine (10 mg/kg) for 20 days into mice bearing A431 xenografts retarded tumor growth and prolonged the survival of mice. Our results suggest a potential antitumor action for amlodipine in vitro and in vivo, which may be in part mediated by inhibiting Ca(2+) influx evoked by the passive depletion of internal Ca(2+) stores and by PLC-linked agonist stimulation.  相似文献   
57.
A 35-year-old man was admitted because of significant hepatic dysfunction with mild splenomegaly and intra-abdominal lymphadenopathy of unknown cause. Infectious mononucleosis was suggested by subsequently detected high fever, pharyngotonsillitis and cervical lymphadenopathy, but IgM to Epstein-Barr virus (EBV) and cytomegalovirus (CMV) showed dual positivity. A definite diagnosis of EBV-induced infectious mononucleosis was established 3 months later on the basis of seroconversion to Epstein-Barr nuclear antigen (EBNA)-IgG positivity and reduced CMV-IgM titer with persistently negative CMV-IgG. This case highlights the initial diagnostic difficulties of EBV-induced infectious mononucleosis particularly in older patients, due to concomitant abnormal humoral immunity and unusual initial manifestations such as significant liver injury and extensive intra-abdominal lymphadenopathy.  相似文献   
58.
The catalase activities in blood and organs of the acatalasemic (C3H/AnLCs(b)Cs(b)) mouse of C3H strain are lower than those of the normal (C3H/AnLCs (a)Cs(a)) mouse. We examined the effects of prior low-dose (0.5 Gy) X-ray irradiation, which reduced the oxidative damage under carbon tetrachloride-induced hepatopathy in the acatalasemic or normal mice. The acatalasemic mice showed a significantly lower catalase activity and a significantly higher glutathione peroxidase activity compared with those in the normal mice. Moreover, low-dose irradiation increased the catalase activity in the acatalasemic mouse liver to a level similar to that of the normal mouse liver. Pathological examinations and analyses of blood glutamic oxaloacetic and glutamic pyruvic transaminase activity and lipid peroxide levels showed that carbon tetrachloride induced hepatopathy was inhibited by low-dose irradiation. These findings may indicate that the free radical reaction induced by the lack of catalase and the administration of carbon tetrachloride is more properly neutralized by high glutathione peroxidase activity and low-dose irradiation in the acatalasemic mouse liver.  相似文献   
59.
60.
A 13-year-old boy was admitted to a local hospital because of pancytopenia. A bone marrow aspiration and biopsy revealed severely hypocellular marrow with no obvious leukemic cells. The diagnosis was severe aplastic anemia, and the patient was treated with antithymocyte globulin and cyclosporin A. A trilineage response was obtained, and the patient became transfusion-independent within 2 weeks. Two months later, the peripheral blood count normalized with an increased bone marrow cellularity. However, the patient was readmitted 5 months later for recurrence of the pancytopenia. A bone marrow aspiration revealed hypocellular marrow with morphologically blastoid cells. A surface marker study revealed the presence of a single clone that was positive for CD7, CD33, CD34, and HLA-DR. A diagnosis of hypoplastic leukemia was made on the basis of morphology and the surface marker studies. Retrospectively, the laboratory findings were the same as those seen at the onset of the disease. The patient did not respond to combination chemotherapy consisting of vincristine, prednisolone, cyclophosphamide, L-asparaginase, and doxorubicin, but administration of etoposide resulted in complete remission. An in vitro study revealed that >95% of the leukemic cells of this patient could be lysed after an incubation with antithymocyte globulin and human AB serum or baby rabbit serum. These findings suggest the efficacy of antithymocyte globulin in treating certain hypoplastic leukemias.  相似文献   
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