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1.
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH.  相似文献   
2.
Postoperative empyema and aspergillosis were diagnosed in a 66-year-old man. Since non-operative therapy was not effective, we performed surgery. On the 8th postoperative day, a covered Ultraflex expandable stent (Boston Scientific, Galway, Ireland) was implanted to make a one-way airway for blocking a major air leak from a bronchopleural fistula causing respiratory distress. His general condition improved gradually, and he was discharged 30 days after stenting. In conclusion, we used a covered Ultraflex expandable stent to make an airway to block an air leak. This may be a new application for this stent.  相似文献   
3.
1. The relationship between work-rate and the antihypertensive effect of exercise in hypertensives, and the mechanism of that effect, were investigated by a crossover clinical trial. 2. Ten mild hypertensives were randomly divided into two groups. One group performed low work-rate exercise (LWE) on a cycle ergometer for 10 weeks (blood lactate threshold; ~50% of maximum oxygen consumption [V?O2max]). After a 10 week interval without exercise training, these subjects were then switched to a high work-rate exercise (HWE) regimen (4 mmol/ L of blood lactate; ~75% of V?O2max) for another 10 weeks. In the other group, the order of exercise training was reversed. Since two patients withdrew from the protocol during HWE periods, statistical analysis was performed on the data from the remaining eight patients. There were no order effects observed in any of the data from the two groups. 3. During both LWE and HWE, resting blood pressure (BP) fell significantly after the initiation of exercise therapy (P<0.05). Furthermore, the overall effects of 10 weeks of LWE and HWE on BP were not significantly different. 4. The work-rate at the lactate threshold, which reflects physical fitness, had increased significantly by 16 W (P<0.01) after the LWE period and by 11 W (P<0.01) after the HWE. 5. During the LWE period, changes in haemodynamic and humoral variables were not significant, except for a reduction in plasma norepinephrine at week 10 (P<0.05). In the HWE period, changes in haemodynamic and humoral variables were not significant. 6. Based on these findings, LWE is recommended for mild hypertensives because of its safety.  相似文献   
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The presence of blood in the ejaculate is called hematospermia or hemospermia. While often perceived as a symptom of little significance, hematospermia can cause great concern to men who experience it. We report an unusual case of hematospermia associated with pelvic arteriovenous malformation (AVM). A 60-year-old man who visited our hospital complaining of hematospermia and pollakisuria was found to have AVM and aneurysmal changes in the left side of the pelvis using computed tomography (CT). The patient was treated with steel coil embolization of the left inferior gluteal artery, and after the procedure the hematospermia and pollakisuria remained absent without flare-ups.  相似文献   
7.
Protein tyrosine phosphatase ζ (PTPζRPTPβ) is a proteoglycan-type receptor-like protein tyrosine phosphatase specifically expressed in the brain. In addition to the transmembrane form (PTPζ-A), the extracellular splice variant (PTPζ-S) occurs as a major soluble chondroitin sulphate proteoglycan in the brain. We prepared antibodies which specifically recognize PTPζ-A and -S, and analysed the carbohydrate structures on the two PTPζ isoforms in the developing chick brain. lmmunoprecipitation experiments using these antibodies revealed that almost all of the keratan sulphate recognized by a monoclonal antibody (5D4) was exclusively bound to PTPζ-A and PTPζ-S. Addition of keratan sulphate to these proteoglycans markedly increased from embryonic day (E) 11, in contrast to the addition of LeX and HNK-1 carbohydrates, which gradually increased during development in accordance with expression of the core proteins, suggesting that keratan sulphate modification plays some specific roles. Moreover, at the early embryonic stage keratan sulphate was observed only in several restricted regions, especially at boundary regions such as the roof plate of the tectum, the zona limitans intrathalamica in the diencephalon, and the mesencephalon-metencephalon boundary. At the mesencephalon-metencephalon boundary, keratan sulphate modification of PTPζ isoforms was specifically observed from E3 to E6 on a ring of cells encircling the neural tube and their radially oriented processes, which were identified as radial glial fibres. This expression pattern of keratan sulphate spatiotemporally corresponded well to the formation of the fovea isthmi, a groove separating the mesencephalon from the metencephalon. These results suggest that carbohydrates including keratan sulphate on PTPζ isoforms play important roles in brain development by modulating the cell-cell and/or cell-substrate interactions mediated by these molecules.  相似文献   
8.
Pharmacokinetic , bacteriological and clinical studies on norfloxacin (NFLX), a quinolone-carboxylic acid antibacterial agent, were conducted in the pediatric field. 1. Serum concentrations and urinary excretion of NFLX after single dose of 2.2 approximately 5.6 mg/kg (mean 4.4 +/- 1.2 mg/kg) were determined in 13 children with ages between 6 and 11 years. The mean peak serum concentration of the drug was 0.37 +/- 0.20 micrograms/ml at 2 hours after administration. The mean half-life of the drug in serum was 2.8 +/- 0.4 hours and the serum concentration at 8 hours was 0.11 +/- 0.06 micrograms/ml. The mean urinary concentration reached a maximum of 125.2 +2- 166.2 micrograms/ml in pooled urine from 0 to 2 hours and the mean urinary recovery rate in the first 8 hours after administration was 22.1 +/- 6.0%. A dose-response relationship was observed between doses/body weight and peak serum concentrations. 2. The clinical efficacy, bacteriological efficacy and the safety of NFLX were evaluated in 65 pediatric patients with ages between 2 years 10 months and 15 years 7 months with infections. In 62 assessable cases (acute purulent tonsillitis 9 cases, acute pneumonia 3 cases, chronic rhinitis 1 case, urinary tract infections 15 cases, and acute colitis 34 cases), clinical efficacies were excellent in 48 cases, good in 13 cases, and fair in 1 case with an overall efficacy rate of 98.4%. Staphylococcus aureus 1 strain, Staphylococcus epidermidis 1 strain, Escherichia coli 10 strains, Salmonella sp. 5 strains, Morganella morganii 1 strain, Pseudomonas aeruginosa 3 strains, Haemophilus parainfluenzae 1 strain and Campylobacter jejuni 12 strains were isolated from the patients as pathogens. Bacteriologically, all of these strains were eradicated except that 3 strains of C. jejuni only decreased. With regard to side effects, dizziness and nausea were observed in 1 case each but they were slight and the continuation of the treatment was possible. No abnormal laboratory test data were observed. From the above results, NFLX was considered to be a useful drug for the treatment of pediatric infections.  相似文献   
9.
OBJECTIVES: Graft failure has been reported when the arterial conduit, such as the internal thoracic artery (ITA) or the right gastroepiploic artery (GEA), is grafted to a lower grade coronary artery stenosis. The shear stress as a significant factor affecting graft patency was compared between the arterial conduit and the saphenous vein graft (SVG) after surgery. METHODS: In 101 patients, 40 ITAs, 27 GEAs and 34 SVGs were examined using a Doppler-tipped guide wire during postoperative angiography. The graft flow volume and shear stress were calculated from velocity and diameter data. The study grafts were classified according to the grade of native coronary artery stenosis: group L had more than 50 up to 75% stenosis, and group H had more than 75% stenosis. Group H consisted of 25 ITAs, 17 GEAs and 21 SVGs, while group L consisted of 15 ITAs, 10 GEAs and 13 SVGs. RESULTS: In group H, graft flow volume did not significantly differ among the ITA (34+/-11 ml/min), GEA (36+/-16 ml/min) and SVG (41+/-15 ml/min), and graft shear stress significantly (ITA vs. GEA P<0.0001; GEA vs. SVG P<0.01) differed among the ITA (16.0+/-4.8dyn/cm(2)), GEA (9.1+/-3.2dyn/cm(2)) and SVG (4.8+/-1.6dyn/cm(2)). In group L, flow volume was lower (P<0.001) in the ITA (18+/-6 ml/min) and GEA (13+/-8 ml/min) than in the SVG (35+/-16 ml/min), and shear stress was significantly (P<0.001) greater in the ITA (13.7+/-4.9dyn/cm(2)) than the GEA (5.6+/-2.0dyn/cm(2)) or SVG (4.6+/-2.0dyn/cm(2)). CONCLUSIONS: These data suggest that shear stress of the ITA is superior and maintained despite the flow volume being reduced by flow competition. Lower shear stress of the GEA for intermediate stenosis may be associated with the development of conduit failure.  相似文献   
10.
The so-called Potter's lesion, previously described as preneoplastic in the lymph nodes of C58 mice, develops frequently in autoimmune NZB mice. These lesions were characterized in the present study by bands or sheets of palestaining histiocytic cells in the cortex and medulla of the lymph node, and multiple small nodules of the same cells were found in the red pulp of the spleen and the liver. Electron microscopically, the cells had pleomorphic cytoplasm with long processes, electron-dense bodies, abundant mitochondria, and a characteristic labyrinth structure with many C-type viruses. Mac-1 antigen, IgG-Fc receptor, ferritin, and ACPase activity were identified on these cells. Intraperitoneally-injected iron colloids were found in the lesions of the spleen and liver but not in those of the lymph nodes. The lymph node lesions appeared when the mice were about 3 months of age and enlarged until the mice were around 10 months old, after which they gradually receded and were replaced by small vessels and fibroblastic cells. These data indicate that the lesions represent reactive hyperplasia of the macrophage system and may have no direct association with the development of malignant lymphoma in NZB mice.  相似文献   
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