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991.
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis of microscopic and macroscopic findings postembolization. Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings: single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth type. Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis) to the SNE type (21%), and the other types (9%).  相似文献   
992.
为了研究包含易位的染色体畸变在辐射诱发淋巴瘤过程中的作用,作者分析了供体型T淋巴瘤细胞的染色体G带核型。结果观察到,在供体派生的T细胞淋巴瘤中,有许多数目和结构畸变。有意义的是:几乎在每组淋巴瘤中都发现了含有易位的共同畸变。如:D组中11号和12号染色体的易位;E组中12号和15号钵体的易位;A组和F组中还有共同的15号染色体三体。这些结果表明:包含易位的染色体畸变在辐射诱发淋巴瘤过程中可能是重要  相似文献   
993.
A 34-year-old woman visited our hospital complaining of dry cough. Chest radiography and computed tomography showed bilateral multiple infiltrative shadows over the lung field. After an initial diagnosis of pneumonia, antibiotics were administered, but the therapy failed to improve the symptoms and abnormalities observed on the chest radiograph. The patient was then admitted to our hospital. The bronchoalveolar lavage fluid (BALF) was slightly bloody, but we were not able to make any specific findings in BALF. In order to confirm the pathological diagnosis, video-assisted thoracoscopic lung biopsy was performed aiming at the right middle and lower lobes. There were bleeding pulmonary infarctions in a biopsy specimen from the right middle lobe. Atypical cells positive for human chorionic gonadotropin (hCG) proliferated in the pulmonary arteries, and so a diagnosis of pulmonary embolic metastasis of choriocarcinoma was made. After the diagnosis, it became clear that urine and serum hCG values were very high. The patient has since received systemic chemotherapy in the gynecology unit at our hospital. Pulmonary embolic metastasis of choriocarcinoma diagnosed by video-assisted thoracoscopic lung biopsy has never been reported in the literature. However, early hCG measurement may have detected this syndrome in the earlier stages, and pulmonary metastasis of choriocarcinoma should be considered in the differential diagnosis of women with past pregnancy presenting with intractable multiple pulmonary shadows.  相似文献   
994.
cDNA clones for the (S)-tetrahydroberberine (H4Ber) oxidase of cultured berberine-producing Coptis japonica cells were isolated by screening a C. japonica cDNA library with synthetic nucleotides that can encode the NH2-terminal sequence of this enzyme. Analyses of the nucleotide sequences of the cloned cDNA inserts revealed a 759-base-pair open reading frame that encoded a 253-amino acid polypeptide with a Mr of 27,089 and NH2-terminal and internal sequences identical with those of the (S)-H4Ber oxidase, as determined by microsequencing methods. Escherichia coli were transformed with an expression vector carrying (S)-H4Ber oxidase cDNA. The transformed bacteria were induced to overproduce a 28-kDa protein that reacted with Coptis (S)-H4Ber oxidase-specific antibody. A comparison of the derived amino acid sequence of (S)-H4Ber oxidase with sequences in the protein data base of the Protein Research Foundation showed a marked similarity between (S)-H4Ber oxidase and the NH2-terminal portion of mouse P1-450, which is encoded by a single exon of the mouse P1-450 gene. The availability of cloned cDNA for (S)-H4Ber oxidase allows use of the methods of molecular biology to study the regulation of (S)-H4Ber oxidase gene expression in cultured C. japonica cells in relation to berberine biosynthesis.  相似文献   
995.
Among 144 patients with hypertrophic cardiomyopathy, eight (58.3 +/- 7.0 years, M:F = 7:1) had complicating myocardial infarction, which was diagnosed clinically and by elevated cardiac enzymes or new Q-waves on electrocardiography. Coronary occlusion or stenosis evidenced by coronary angiography and nuclear cardiological findings were investigated. In six of the eight patients, coronary atherosclerosis caused infarction. These patients had many coronary risk factors compared to the other two patients. Sixteen of the 144 patients (11%) with hypertrophic cardiomyopathy had coronary atherosclerosis, the rate of which is reportedly 10 to 20%. Two of the eight patients had no coronary atherosclerosis. One patient had a diffusely spastic diathesis provoked by the intravenous administration of ergonovine maleate during coronary angiography, suggesting that coronary spasm caused myocardial infarction. The other patient had recurrent episodes of supraventricular tachyarrhythmia and no evidence of spasm during coronary angiography, suggesting coronary embolism as a cause of myocardial infarction. Myocardial infarction in patients with hypertrophic cardiomyopathy and normal coronary arteries as advocated by Maron et al. may have such pathogenesis. We conclude that coronary angiography may be mandatory in patients with hypertrophic cardiomyopathy, especially those who have many coronary risk factors and anginal symptoms. In these patients, ST-T changes and abnormal Q-waves on electrocardiography sometimes may be misleading when diagnosing the occurrence of acute myocardial infarction by electrocardiography alone. In such cases, infarct-avid scintigraphy with 99 m-Tc pyrophosphate is preferable.  相似文献   
996.
OBJECTIVE: The pteridine cofactor tetrahydrobiopterin (BH4) has emerged as a critical determinant of endothelial nitric oxide synthase (eNOS) activity. When BH4 availability is limited, eNOS does not produce nitric oxide (NO) but instead generates superoxide. BH4 may reverse endothelial dysfunction due to cardiovascular disease, including atherosclerosis, coronary artery disease and hypertension. In this study, the influence of BH4 on cardiovascular parameters and the production of free radicals following angiotensin II (Ang II) infusion was assessed. METHODS: BH4 (20 mg/kg per day in drinking water) was administered with Ang II (300 ng/kg per min subcutaneously, osmotic pump) for 7 days in Sprague-Dawley rats. In addition, BH4 was also given in vehicle-infused rats. RESULTS: Treatment with BH4 significantly prevented some of the effects of Ang II, such as impaired vascular responses to acetylcholine, hypertension and increases in heart weight index values. Treatment with BH4 also significantly reduced Ang II-induced increases in inducible NO synthase expression, nitrotyrosine immunostaining, NO production and superoxide anion formation in rats. CONCLUSION: These results indicate that BH4 might prevent the development of hypertension and myocardial hypertrophy, as well as the Ang II-induced production of superoxide and NO, thereby reducing the production of peroxynitrite. Therefore, BH4 may protect against the cardiovascular manifestations of oxidative and nitrosative stress in this experimental model of Ang II-mediated hypertension.  相似文献   
997.
Sawada S  Watanabe Y  Moriyama S 《Chest》2005,127(6):2226-2230
STUDY OBJECTIVES: Video-assisted thoracoscopic surgery (VATS) is effective for primary spontaneous pneumothorax. We sought to evaluate the outcome of VATS compared to conservative treatment and open thoracotomy, and to discuss the indications for VATS in primary spontaneous pneumothorax. DESIGN: Retrospective study. PATIENTS AND INTERVENTIONS: Primary spontaneous pneumothorax was diagnosed in 281 consecutive patients between January 1989 and April 2001. Mean age was 29.1 years. Mean follow-up period was 78.3 months (range, 13 to 163 months). For these patients, conservative treatment, open thoracotomy, or VATS were performed, and the outcomes of the three treatments were evaluated. If recurrence occurred, outcome of treatment for the recurrence was also evaluated according to the number of times of recurrence. RESULTS: Recurrences were observed in 109 of 281 patients (38.8%). Forty-three patients (15.3%) had repeat recurrences. Regarding the outcome of the first episode, recurrence rates were 54.7% for conservative treatment, 7.7% for open thoracotomy, and 10.3% for VATS. Recurrence rates after the second episode were 60.3% for conservative treatment, 0% for open thoracotomy, and 18.6% for VATS. Overall recurrence rates of each treatment were 56.4%, 3.0%, and 11.7%, respectively. There was no statistical difference between the open thoracotomy and VATS groups (p = 0.15). Hospital stays from operation until discharge were 11.5 days for open thoracotomy and 4.1 days for VATS (p < 0.001). CONCLUSION: The outcomes of VATS were very good compared to conservative treatment and equal to those of the open thoracotomy, not only for the first episode but also for the case of recurrence. In terms of low morbidity, low invasiveness, and cosmetic issues, VATS is superior to open thoracotomy. VATS is standard in cases of recurrence and should be considered for treatment at the first episode.  相似文献   
998.
BACKGROUND: To find chest roentgenographic (CXR) features to help differentiate two representative diseases with severe chronic pulmonary hypertension (PH). STUDY SUBJECTS: Thirty-six consecutive patients with chronic thromboembolic PH (CTEPH), 38 with primary PH (PPH), and 37 with left heart disease and PH. METHODS: CXRs were reviewed about 6 features (left 2nd arc protrusion, right descending pulmonary artery diameter (rPAD), cardiothoracic ratio (CTR), right 2nd arc width, avascular area and pleural abnormality). Hemodynamic data and the degree of tricuspid regurgitation (TR) on echocardiography were compared with CXR findings. RESULTS: The diagnostic pattern of CTEPH was the presence of one of two findings, an avascular area or marked rPAD (>20mm) together with pleuritic change. The diagnostic pattern of PPH was one of the two features; without pleuritic abnormality, marked left 2nd arc protrusion (>10mm) or moderate left 2nd arc protrusion (5-10mm) with marked rPAD (<20mm). The sensitivity for the diagnosis of CTEPH among the three diseases was 78% and specificity was 92%. The sensitivity for the diagnosis of PPH was 45% and specificity was 88%. CTR and right 2nd arc width were related to the degree of TR in CTEPH and PPH. CONCLUSIONS: Characteristic roentgenographic findings can help differentiate two frequent diseases associated with chronic pulmonary hypertension and reflect the severity of disease.  相似文献   
999.
The response of blood pressure to thiazide diuretics (TZDs) differs among individuals. The prediction of the antihypertensive effect of TZDs is important for realizing individualized therapy in the management of hypertension. The aim of this study was to identify the single nucleotide polymorphisms (SNPs) susceptible to the antihypertensive effect of TZDs, particularly focusing on genes related to water-electrolyte absorption in the kidney. Seventy-six outpatients (mean age, 65.4+/-9.0 years) with essential hypertension (EHT) taking TZDs were retrospectively assessed. We defined as responders (R) those whose mean blood pressure was lowered by more than 5 mmHg after the use of TZDs. Forty-eight SNPs in 17 genes (ADD1, GNB3, TSC [SLC12A3], MLR [NR3C2], NCX1 [SLC8A1], WNK1, WNK4, AGT, ACE, AT1 [AGTR1], CYP11B2, ADRB1, ADRB2, ADRB3, ADRA1A, ADRA1B, ADRA2A) were genotyped in the 76 patients. The SNPs in TSC, MLR, NCX1, WNK1, and WNK4 were identified by direct sequencing and those with minor frequencies of greater than 5% were genotyped in this study. The comparison of polymorphism prevalence between R and non-responders (NR) showed significant differences in TSC C1784T (C allele vs. T allele, odds ratio (OR)=3.81, p =0.016, confidence interval (CI): 1.25-11.63) and ADRB3 T727C (Trp64Arg) (T allele vs. C allele, OR=4.59, p =0.005, CI: 1.54-13.68). The blood pressure (BP) in patients homozygous for the major alleles of both TSC C1784T and ADRB3 T727C were significantly reduced by TZD treatment; however, the BP in those homozygous for the minor allele and heterozygous (TSC C1784T: TT+CT; ADRB3 T727C: CC+CT) for both SNPs were not significantly changed after TZD treatment. Both newly detected TSC C1784T and ADRB3 T727C are gene polymorphisms susceptible to the antihypertensive effect of TZDs in patients with EHT. Thus, the prediction of BP reduction by TZDs may be possible by evaluating these two SNPs.  相似文献   
1000.
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