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21.
Bronchiectasis with normal paranasal sinus roentgenogram   总被引:1,自引:0,他引:1  
Bronchiectasis has come to be considered as a type of sinobronchial syndrome in Japan, but there exist some cases without chronic sinusitis. We studied the clinical features of 14 cases of bronchiectasis with definitely normal paranasal sinus roentgenogram, diagnosed during the past ten years. There were eleven middle-aged women and three men. Ten patients (71%) complained of hemoptysis, one (7%) of dry cough, one (7%) of productive cough, and the two (14%) had no complaint. In seven patients (50%) CT and bronchography showed localized cylindrical bronchiectasis in the right middle lobe and/or left upper lobe lingular division. They were considered to be middle lobe lingular syndrome. Three patients (22%) with localized varicose or cystic bronchiectasis had a history of pneumonia or pertussis in their infancy, so their bronchiectasis were considered secondary to infantile bronchopulmonary disease. Two patients (14%) had diffuse cystic bronchiectasis and were almost asymptomatic. They might be cases congenital bronchiectasis or Williams-Campbell syndrome. Pulmonary function tests were normal in most of the cases and sputum culture revealed no cases of persistent bacterial infection. These clinical features are quite different from those of bronchiectasis reported as sinobronchial syndrome, in which chronic productive cough, poor pulmonary function, persistent bacterial infection, etc. are significant. So we conclude that there are two distinct groups in bronchiectasis.  相似文献   
22.
BACKGROUND: Endoscopic mucosal resection is an established treatment option for early stage gastric cancer. However, several problems with endoscopic mucosal resection remain to be solved, such as appropriate treatment for recurrence and incomplete tumor resection. The outcome for patients undergoing endoscopic aspiration mucosectomy (endoscopic mucosal resection) by a modification of the cap-fitted technique was evaluated retrospectively to determine factors associated with complete resection and tumor recurrence. METHODS: Endoscopic mucosal resection was performed in 106 patients with early stage gastric cancers up to 20 mm in diameter that were well or moderately differentiated adenocarcinoma. All were superficial lesions without ulceration, distinct signs of submucosal invasion, or a poorly demarcated border. En bloc (tumors <10 mm in diameter) or piecemeal (tumors 10-20 mm in diameter) resection was performed. Follow-up endoscopy was performed at 2, 6, 12, 18, and 24 months and thereafter once per year. Outcome and factors associated with complete resection and tumor recurrence were assessed retrospectively. RESULTS: Sixty-eight patients (64%) underwent en bloc resection and 38 (36%) piecemeal resection. The mean longest dimension (SD) of the resected lesions was significantly greater after piecemeal resection (12.3 [4.0] mm) than after en bloc resection (7.6 [4.0] mm; p < 0.01). In patients with tumors completely resected, there was no recurrence after either en bloc or piecemeal resection. Six of 8 patients found to have submucosal invasion after endoscopic mucosal resection underwent surgery. Patients with incompletely resected intramucosal lesions underwent additional endoscopic treatment. Cancer recurred in 3 patients (2.8%), all of whom had lesions measuring more than 15 mm in diameter. CONCLUSIONS: Endoscopic mucosal resection is safe and useful for the management of early stage gastric cancer. Further improvement in outcome requires more accurate preoperative diagnosis and postoperative histopathologic evaluation. Patients with incompletely resected lesions should undergo aggressive additional treatment.  相似文献   
23.
BACKGROUND: The beneficial effect of percutaneous coronary intervention (PCI) using stents for acute myocardial infarction (AMI) has already been demonstrated, but there is the problem that mechanical microvascular occlusion can occur because of thrombus/atheroma embolization when the PCI was performed. The aim of the present study was to retrospectively test and compare the effects of an aspiration catheter or distal embolic protection with a distal occlusion balloon catheter to prevent peripheral vascular embolization. METHODS AND RESULTS: The subjects consisted of 135 patients who underwent PCI with stenting within 12 h of the onset of chest pain caused by their first AMI. They were divided into 2 groups; the aspiration group, consisted of 81 consecutively seen patients who underwent aspiration catheter treatment between January 2001 and May 2002, and the distal protection group was the next group of 54 consecutively seen patients treated with a distal protection device between June 2002 and February 2003. The results were as follows. Thrombolysis in Myocardial Infarction (TIMI) score of 3 was obtained significantly more frequently in the distal protection group (94.4%) than in the aspiration group (79.0%). Additionally, the intensity of the cardiac muscle stain (blush score) was evaluated on coronary angiography and the rate of cases showing a blush score of 3, which indicates favorable blood perfusion at the tissue level, in the distal protection group (56.6%) was significantly greater than in the aspiration group (33.3%, p<0.01). The time to peak blood concentration of creatinine kinase was also significantly shorter in the distal protection group. CONCLUSIONS: The distal embolism protection method is superior to the aspiration method for prevention of embolization after PCI with stenting for AMI, in terms of tissue level reperfusion in myocardial recanalization therapy.  相似文献   
24.
Estrogen and non-feminizing estrogen for Alzheimer's disease   总被引:3,自引:0,他引:3  
The preventive effect of estrogen on Alzheimer's disease (AD) has become clearer with many epidemiological reports. However, the therapeutic effects of estrogen have been controversial until now. In our trials, estrogen treatment showed a beneficial therapeutic effect for women with mild to moderate AD. Improvement of cognitive function was recognized during the third week from the beginning of administration and maintained as long as estrogen treatment continued. The longer the duration of HRT, the more HRT is useful for the prevention and therapy of AD. However, in most cases, administration of estrogen is discontinued because of the adverse effects on the uterus and breast. J 861 is a derivative of estradiol-17alpha, which has little effect on the sexual organs. The effects of estradiol-17beta (E2) and J 861 on neuronal function and vascular factors were investigated. J 861 was suggested to prevent both the intracellular calcium increase and peroxidation induced by amyloid beta (Abeta), more effectively than E2. The effect of J 861 may be related with both the direct non-genomic and the ER-mediated systems. J 861 showed neurotrophic effects like E2. J 861 inhibited the adhesion of monocytes to vascular endothelium, more effectively than E2. Also, J 861 suppressed the expression of adhesive factors, such as E-selectin and intercellular cell adhesion molecule-1 (ICAM-1), more effectively than E2.  相似文献   
25.
Background/Aims: Colon interposition is the most commonly used method of esophageal reconstruction when the stomach cannot be used; however, this method may cause surgical complications such as anastomotic leakage and sepsis due to colon necrosis. Therefore, many surgeons use a retrosternal or subcutaneous route because it is easier to manage the subcutaneous drainage when anastomotic leakage occurs. However, some researchers have reported that the posterior mediastinal route provides better long-term functional outcomes after surgery than the anterior mediastinal route. Thus, in this study, we compared these reconstruction routes used for colon interposition, with or without the supercharge technique, in patients with a history of distal gastrectomy, who have undergone colon interposition after esophagectomy. Methodology: We retrospectively studied 30 patients who underwent esophagectomy with colon interposition. These patients were divided into 2 groups based on the reconstruction route: the anterior mediastinal or subcutaneous route (A group), or the posterior mediastinal route (R group). Results: Anastomotic leakages were observed in 4 patients (26.7%) in the A group and in 1 patient (6.7%) in the R group. Conclusions: Ischemia is not always the result of arterial failure, but may also originate from venous blood flow impairment due to injury or distortion of veins.  相似文献   
26.
27.

Objectives

To test the null hypothesis that polymerization-induced stress was not influenced by cavity dimensions and geometries.

Methods

Four experimental groups, with different C-factors and specimen volumes were defined using bottom-less glass disks (height: 1 or 2 mm) with a central hole 3 or 6 mm in diameter, and 3 mm wall thickness. Another four groups were created by bonding a glass plate to the bottom of the disks. Additionally, disks with 2-mm height, 3 mm in cavity diameter, and 4.5-mm thick walls were prepared. Vickers indents (9.8 N, 20 s) were made at the top surface at 600 μm from the cavity margin. The lengths of the indentation diagonal and the corner cracks parallel to the cavity margin were measured. Ten minutes after restoration (Majesty Esthetic, Kuraray), cracks were re-measured. Stresses at the indent site were calculated based on glass fracture toughness and increase in crack length. Data were subjected to ANOVA/Tukey or Kruskal–Wallis/Mann–Whitney tests (alpha: 5%, n = 8). Finite element analysis (FEA) was used to estimate stress at the interface and the effective structural rigidity of the substrate.

Results

Overall, for experimental and FEA results, cavities developed higher stress than bottom-less disks. Increasing wall thickness did not affect stress. When similar geometries and C-factors were compared, higher volumes developed higher stress and had greater incidence of margin cracking.

Clinical significance

C-factor is a suitable predictor for polymerization stress in low compliance environments, particularly due to its simplicity. However, the influence of cavity size cannot be disregarded especially for the development of marginal cracking. The interaction between size, geometry and stiffness is likely to become more complex according to the complexity of the cavity shape.  相似文献   
28.
A 75-year-old woman with a history of myocardial infarction, gallstones, and right renal cancer was referred to our department because of right flank pain. She had a surgical scar on the right abdomen between the 10th and 11th ribs; computed tomography demonstrated intercostal herniation of the colon. Recognizing the possibility of adhesions of the hernia and colon, we used a median skin incision and patched a polyester mesh coated with absorbent collagen. The patient had an uneventful postoperative course, with no pain for 6 months postoperatively. Transdiaphragmatic intercostal hernias with abdominal contents commonly develop after trauma or thoracic surgery. Incisional intercostal hernias seldom develop after nephrectomy; the present case is only the fourth report. We conjecture that a costochondral incision can induce subluxation of the costotransverse joint, intercostal nerve injury, and atrophy of the intercostal and abdominal oblique muscles. Surgeons must therefore recognize the potential, albeit rare, for intercostal hernia after nephrectomy.  相似文献   
29.

Background

Epidermal growth factor receptor (EGFR) signaling is one of the most promising targets for molecular-targeted therapies in esophageal squamous cell carcinoma (ESCC). Thus, the molecular diagnosis of KRAS and BRAF mutations is clinically important in therapeutic decision making. However, the frequency of KRAS and BRAF mutations in ESCCs remains inconclusive because of the limited sample sizes of previous studies (all N ≤ 80). Pyrosequencing is a nonelectrophoretic nucleotide extension sequencing technology that can be used for mutation testing.

Methods

The frequency of KRAS and BRAF mutations was examined using a nonbiased database of 203 resected ESCCs and a high-throughput pyrosequencing assay.

Results

The validity of the KRAS pyrosequencing method was initially demonstrated by detection of all 4 types of KRAS mutations [c.35G>T (codon 12 GGT>GTT), c.35G>A (codon 12 GGT>GAT), c.34G>T (codon 12 GGT>TGT), c.38G>A mutation (codon 13 GGC>GAC)], which had been previously diagnosed using Scorpion-ARMS technology, in 9 colon cancer tissues (9 of 9; 100 %). Similar results were demonstrated for BRAF mutational status in 3 colon cancer cell lines (HCT116, Colo201, and HT29), which were validated by Sanger dideoxy sequencing. Subsequently, the KRAS mutation was found to be extremely rare (1 of 203; 0.5 %), and the BRAF mutation was absent (0 of 203; 0 %), in the dataset of 203 ESCCs.

Conclusions

These results suggest that KRAS and BRAF mutations play a limited role in the development of ESCC and that mutation analysis is not useful as a screening test for sensitivity to anti-EGFR therapy in ESCC.
  相似文献   
30.
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