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31.

Background  

This study investigated issues related to initial stability after stem fixation. Finite element models of the AI-Hip cementless stem were constructed for computer simulation.  相似文献   
32.
Background The cellular immune system is the most dominant factor in curing acute dermatophytosis. However, the exact immune mechanisms involved in generating this defense are complex and still obscure. The aim of this study was to investigate the fungicidal mechanism of T cells in the normal population versus patients with chronic fungal infections. Methods Thirty patients were included in the study: 15 patients with chronic dermatophytosis and 15 normal healthy patients with a history of acute dermatophytosis. The procedures were performed as follows. 1) Proliferation and cytotoxic activity of lymphocytes cultured with various dermatophytes homogenate such as, Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum gypseum. 2) CD4+ and CD8+ T cells were separated by magnetic beads before culture with fresh spores of either T. mentagrophytes or T. rubrum. 3) Routine histology and ultrastructural study were performed to illustrate the mode of activity of the T cells against the dermatophytes. Results The study showed that both CD4 and CD8 possess cytotoxic activity against dermatophytes. However, the results demonstrated a suppression of lymphocyte proliferation response and a significant lower cytotoxic effect in chronic patients. Ultra structure and histological evaluation of the culture of hyphae with CD4+ or CD8+ T cells showed more prominently destructive effects in the culture of cells that had been obtained from normal population than those of patients with long‐lasting fungal infections. Conclusion The study suggests a selective impairment of lymphocyte function against dermatophytes, in patients with chronic dermatophytoses.  相似文献   
33.
BACKGROUND/AIMS: The anti-cancerous effect on hepatocellular carcinoma of a newly established form of thermotherapy, which uses an implant heating system, was evaluated. As a new material for application in hyperthermia, the authors developed a powder type Mg-ferrite complex that produces heat under a relatively low-power magnetic field. METHODOLOGY: This material suspended in Lipiodol was injected into tumors on the backs of mice that consisted of human hepatocellular carcinoma cells. Hyperthermia was performed by directing a magnetic charge on tumor-bearing mice that contained the Mg-ferrite complex. The temperature of the tumor was kept at 42-43 degrees C, while the magnetic field power ranged from 50 to 80G. RESULTS: A 10-min hyperthermia treatment was insufficiently effective against tumor growth. Systemic injection of doxorubicin (ADM) before hyperthermia appeared to enhance the anti-cancerous effect, but the difference was little and did not reach a statistically significant level (repeated measure analysis of variance). The anticancerous effect of hyperthermia for 15 minutes, in contrast, was marked. The nodules had almost completely disappeared by the end of the experiment. CONCLUSIONS: In conclusion, it is suggested that hyperthermotherapy using this newly developed Mg-ferrite complex might become an option for low-invasive therapy for advanced hepatocellular carcinoma in humans.  相似文献   
34.
Endobronchial lipoma: review of 64 cases reported in Japan   总被引:2,自引:0,他引:2  
Muraoka M  Oka T  Akamine S  Nagayasu T  Iseki M  Suyama N  Ayabe H 《Chest》2003,123(1):293-296
BACKGROUND: Several recent studies discuss bronchoscopic techniques for treating endobronchial lipoma, an extremely rare benign tumor. OBJECTIVES: To describe the epidemiology of endobronchial lipoma and to propose appropriate therapeutic policies for treating this tumor. METHODS: We reviewed 64 cases of endobronchial lipoma: 33 cases previously reported in 30 different articles, and 31 case reports presented at thoracic meetings in Japan. RESULTS: Of the 64 patients included in this study (50 male and 14 female; mean age, 60 years), 40 patients had endobronchial lipoma in the right lung and 23 patients had it in the left lung. The overwhelming majority of the tumors (n = 61) were found in the first three subdivisions of the tracheobronchial tree. Forty-eight patients (75%) were symptomatic, and their symptoms included cough, sputum, hemoptysis, elevated temperature, and dyspnea. Additionally, abnormal radiographic findings were reported for 51 patients (80%): 18 patients had atelectasis, 14 patients had infiltration or consolidation, 6 patients showed volume loss of the lung, and mass shadow was identified in 9 patients, and another abnormality including pleural effusion was found in 4 patients. Forty patients underwent surgical resection: 4 pneumonectomies, 24 lobectomies, 8 bilobectomies, and 4 resections by bronchotomy. Bronchoscopic resection was carried out in 17 cases: 7 cases by Nd-YAG laser, 5 cases by electrosurgical snaring forceps, and another 5 cases with a combined therapy using both procedures. CONCLUSIONS: Bronchoscopic resection should be considered as the first choice of treatment for endobronchial lipoma; however, surgical therapy is indicated for patients who show the possibility of a complicated malignant tumor, who have destructive peripheral lung disease, who have extrabronchial growth, or who may have technical difficulties during the bronchoscopic procedure.  相似文献   
35.
36.
Musunuri  Balaji  Tripathy  Rina  Padhi  Sunali  Panda  Aditya K.  Das  Bidyut K. 《Clinical rheumatology》2022,41(11):3337-3344
Clinical Rheumatology - The distinction between infection and flare in systemic lupus erythematosus (SLE) has always been a dilemma for clinicians as the clinical and biochemical profiles overlap....  相似文献   
37.
Kihara  Mari  Sugihara  Takahiko  Asano  Junichi  Sato  Midori  Kaneko  Hiroshi  Muraoka  Sei  Ohshima  Shiro  Nanki  Toshihiro 《Clinical rheumatology》2022,41(12):3661-3673
Clinical Rheumatology - To describe clinical characteristics of patients in Japan with coronavirus disease 19 (COVID-19) and pre-existing rheumatic disease and examine the possible risk factors...  相似文献   
38.
Congenital factor VII (FVII) deficiency is a rare bleeding disorder with autosomal recessive inheritance. The present female patient was diagnosed with congenital FVII deficiency because of low hepaplastin test (HPT), although vitamin K was given. Heterozygous p.A191T mutation was detected in the peripheral blood, and the same mutation was also found in the mother and sister. To the best of our knowledge, this is the fourth reported case of p.A191T mutation of FVII in the literature and the first to be reported in Japan. FVII coagulation activity (FVII:C) in asymptomatic heterozygous carriers is mildly reduced. Therefore, some patients may not be accurately diagnosed with congenital FVII deficiency. In infants with low HPT without vitamin K deficiency, congenital FVII deficiency should be considered.  相似文献   
39.
Sickle cell disease is characterized by chronic hemolytic anemia and vaso-occlusive painful crisis. The vascular occlusion in sickle cell disease is a complex process and accounts for the majority of the clinical manifestations of the disease. Abdominal pain is an important component of vaso-occlusive painful crisis and may mimic diseases such as acute appendicitis and cholecystitis. Acute pancreatitis is rarely included as a cause of abdominal pain in patients with sickle cell disease. When it occurs it may result form biliary obstruction, but in other instances it might be a consequence of microvessel occlusion causing ischemia. In this series we describe four cases of acute pancreatitis in patients with sickle cell disease apparently due to microvascular occlusion and ischemic injury to the pancreas. All patients responded to conservative management. Acute pancreatitis should be considered in the differential diagnosis of abdominal pain in patients with sickle cell disease.  相似文献   
40.

Background

Heart failure (HF) is characterized by altered myocardial substrate metabolism which can lead to myocardial triglyceride accumulation (steatosis) and lipotoxicity. However its role in mild HF with preserved ejection fraction (HFpEF) is uncertain. We measured myocardial triglyceride content (MTG) in HFpEF and assessed its relationships with diastolic function and exercise capacity.

Methods

Twenty seven HFpEF (clinical features of HF, left ventricular EF >50%, evidence of mild diastolic dysfunction and evidence of exercise limitation as assessed by cardiopulmonary exercise test) and 14 controls underwent 1H-cardiovascular magnetic resonance spectroscopy (1H-CMRS) to measure MTG (lipid/water, %), 31P-CMRS to measure myocardial energetics (phosphocreatine-to-adenosine triphosphate - PCr/ATP) and feature-tracking cardiovascular magnetic resonance (CMR) imaging for diastolic strain rate.

Results

When compared to controls, HFpEF had 2.3 fold higher in MTG (1.45?±?0.25% vs. 0.64?±?0.16%, p?=?0.009) and reduced PCr/ATP (1.60?±?0.09 vs. 2.00?±?0.10, p?=?0.005). HFpEF had significantly reduced diastolic strain rate and maximal oxygen consumption (VO2 max), which both correlated significantly with elevated MTG and reduced PCr/ATP. On multivariate analyses, MTG was independently associated with diastolic strain rate while diastolic strain rate was independently associated with VO2 max.

Conclusions

Myocardial steatosis is pronounced in mild HFpEF, and is independently associated with impaired diastolic strain rate which is itself related to exercise capacity. Steatosis may adversely affect exercise capacity by indirect effect occurring via impairment in diastolic function. As such, myocardial triglyceride may become a potential therapeutic target to treat the increasing number of patients with HFpEF.
  相似文献   
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