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21.
Denopamine (15 mg/day) was administered to 20 patients with residual left ventricular dysfunction after successful percutaneous transluminal coronary angioplasty (75% or more diameter stenosis). Echocardiography was performed before and 6 months after denopamine administration to analyze the left ventricular function. There were significant decreases in both end-diastolic and end-systolic dimensions from 58 +/- 8.3 to 54 +/- 8.4 mm (p = 0.001), and from 44 +/- 10.1 to 40 +/- 10.3 mm (p = 0.005)), respectively, while % fractional shortening remained nearly constant (from 25 +/- 8.3 to 27 +/- 9.6%). Thus, denopamine improved the left ventricular function by decreasing left ventricular size while maintaining wall contractility.  相似文献   
22.
The calcifying cystic odontogenic tumor is a rare benign odontogenic lesion. This report documents a case of this lesion associated with odontoma arising from the anterior maxilla in a 14-year-old boy. The diagnosis was confirmed based on computerized tomography findings, which clearly depicted the internal structures obscured in conventional images.  相似文献   
23.
The authors examined pulmonary hemodynamics with respect to underlying diseases, severity and type of chronic respiratory failure, and the incidence and effect of home oxygen therapy (HOT) in 155 patients with chronic lung diseases (old pulmonary tuberculosis (OTB) 45, chronic pulmonary emphysema (CPE) 54, chronic bronchitis (CBR) 42 and fibrosing lung disease (FLD) 14). They underwent right heart catheterization during a stable period, while breathing room air. The arterial PO2 ranged from 64.3 +/- 9.7 Torr (CBR) to 69.9 +/- 10.0 Torr (CPE), and the mean pulmonary arterial pressure ranged from 17.3 +/- 4.6 mmHg (CPE) to 20.6 +/- 5.4 mmHg (OTB). The incidence of pulmonary hypertension (PH, PA mean greater than or equal to 20 mmHg) was 53.3% in OTB, 40% in CBR, 35.7% in FLD, 23.8% in CPE, 69% in respiratory failure, 40% in quasi-respiratory failure, and 2.1% in non-respiratory failure. The percentage of patients who received HOT was 84.5% in respiratory failure and 54.1% in quasi-respiratory failure. Comparing Type I with Type II chronic respiratory failure, the incidence of PH was lower in the former than the latter (38.3% vs 80.6%), whereas HOT was applied to an equal percentage of patients (67.4%) in both groups. The effect of HOT was evaluated in 11 patients with chronic respiratory failure. The mean pulmonary arterial pressure was 22.7 +/- 4.7 mmHg before HOT, and decreased to 20.7 +/- 5.6 mmHg after 24.5 +/- 10.1 months of HOT. Although this difference was not significant statistically, this result suggests the desirable effect of HOT on pulmonary hemodynamics.  相似文献   
24.
The authors studied the effects of natural panting frequency (NF) and the cheek support on the plethysmographic measurement of thoracic gas volume (TGV) in 8 normal subjects (non-smokers) and 46 patients with chronic obstructive pulmonary disease (COPD). The patients were divided into 2 groups according to the degree of airway obstruction (group I; specific airway conductance (SGaw) greater than 0.1 (n = 18), group II; SGaw less than 0.1 (n = 28)). TGV was measured with a pressure-type body plethysmograph (BP). NF was 2.00 +/- 0.43 Hz (mean +/- SD) in control subjects, 1.92 +/- 0.78 Hz in group I, and 1.39 +/- 0.59 Hz in group II, respectively, indicating lower NF in the patients with severe airway obstruction. In control subjects and group I, the differences between TGV at NF and at 0.5-1.0 Hz (TGVNF-TGV1.0) were -0.01 +/- 0.07L, and -0.06 +/- 0.16L, respectively, and cheek support did not alter the difference. On the other hand, in group II, the difference was slightly larger than other groups in spite of the lower NF, and this overestimation was abolished by cheek support (0.13 +/- 0.25L-----0.06 +/- 0.27L, p less than 0.05). These results suggest that, in patients with severe airway obstruction, TGVNF may be overestimated even if NF is relatively low. This overestimation may be mainly due to the extrathoracic airway compliance including the cheek.  相似文献   
25.
The present study investigated the influence of hydrostatic prssure on the exprssion of cytokines and heat shock protein 70 in a chondrocyte-like cell line. Chondrocyte-like cells (HCS-2/8) were exposed to hydrostatic pressur by a special pressure apparatus. Total RNA for cytokines (interleukin-1β, basic fibroblast growth factor, insulin-like growth factor-I, and transforming growth factor-β1) and for heat shock protein 70 was extracted and was analyzed by a polymerase chain reaction method and Northern blotting. An assay for incorporation of [35S]sulfate was performed to assess proteoglycan synthesis. The expression of transforming growth factor-β1 mRNA was enhanced after exposure to 5 Mpa of hydrostatic prssure and was reduced after 50 Mpa, whereas the expression of heat shock protein 70 was enhanced following exposure to 50 Mpa of hydrostatic pressure. The incorporation of [35S]sulfate into the cultured cells increased following exposure to 1-5 Mpa of hydrostatic pressure and decreased following 10-50 Mpa of pressure. These results suggest that hydrostatic pressure at physiologic levels enhances the expression of transforkming growth factor-β mRNA in addition to increasing proteoglycan synthesis in chondrocytes and that excessively high hydrostatic pressure reduces the expression of transforming growth factor-β1 mRNA and increases the expression of heat shock protein 79 mRNA while decreasing proteoglycan synthesis.  相似文献   
26.
Following a preliminary study in healthy blood donors, we have performed serological HLA-A, B, C, DR and DQ typing using recombinant IL-2 activated T lymphocytes (IL-2.aTLs) in pediatric candidates for allogeneic bone marrow transplantation. In such patients, it is often difficult to obtain the quantity of lymphocytes required for HLA typing, particularly for class II typing using B lymphocytes, considering the timing of sampling and the volume of blood to be collected. Peripheral blood mononuclear cells (PBMCs) were activated and expanded with IL-2 until a sufficient number of IL-2.aTLs of good viability were available for the typing. In the first 10 cases, analyses of surface markers (CD2, CD20, CD25, CD36, HLA-DR and HLA-DQ, CD2/HLA-DR: two color) of IL-2.aTLs were done using flow cytometry at the time of HLA typing and indicated that IL-2.aTLs expressed HLA-DR and DQ antigens sufficient for evaluation. A small number (less than 10(6] of fresh or cryopreserved PBMCs, even those containing leukemic blast cells, were sufficient to induce and expand IL-2.aTLs for HLA typing. To date we have been able to successfully HLA-A, B, C, DR and DQ type 20/20 pediatric candidates. The HLA antigens identified on the patients' IL-2.aTLs were confirmed by a family study.  相似文献   
27.
The activity of 12 antibiotics, piperacillin, cefazolin, cefotiam, ceftizoxime, latamoxef, ceftazidime, cefuzonam, amikacin, ofloxacin, imipenem, aztreonam and minocycline, against 120 isolates of Pseudomonas aeruginosa was examined. In addition, the efficacy of antibiotics against single-, double-, or triple-drug-resistant isolates of P. aeruginosa were also examined to determine the cross-resistance to each drug. There was cross-resistance between piperacillin, ceftazidime and aztreonam, but amikacin and imipenem remained effective antibiotics, especially as salvage therapy, against isolates resistant to one agent. Results also suggested that piperacillin, ceftazidime or imipenem in combination with amikacin are effective combination regimens against most clinical isolates of P. aeruginosa. Amikacin and imipenem were also suitable antibiotics, especially as salvage therapy, against isolates of P. aeruginosa resistant to two agents. In conclusion, the results provide useful guidelines for choosing an effective treatment against clinical isolates of P. aeruginosa, and for choosing salvage therapy against resistant P. aeruginosa.  相似文献   
28.
 To examine mechanism(s) underlying the accentuated antagonism by angiotensin II (A-II) on twitch tension, we recorded L-type Ca2+ currents (I Ca,L) using conventional patch-clamp techniques in single, guinea-pig, ventricular myocytes. I Ca,L was recorded by a step-pulse protocol after eliminating K+ conductances (internal Cs+ plus tetraethylammonium chloride and K+-free extracellular solution). A-II (100 nM) did not affect basal I Ca,L, but inhibited I Ca,L that had been enhanced (approximately 200% of control) by (ISO, isoproterenol 100 nM). The inhibitory action of A-II was concentration dependent (concentration eliciting 50% inhibition 88±9 pM, n=41) and the ISO-enhanced component of I Ca,L was completely blocked by A-II at concentrations above 10 nM. CV-11974 (500 nM), an A-II type-1 receptor (AT1) antagonist, prevented the inhibitory action of A-II. Pre-incubation with pertussis toxin (PTX) abolished the inhibitory effect of A-II. A-II also inhibited the I Ca,L enhanced by histamine (500 nM) and forskolin (1 μM), but failed to affect I Ca,L enhanced by intracellular cyclic adenosine monophosphate (1 mM). The inhibitory action of A-II may therefore involve AT1 receptors/PTX-sensitive, guanine nucleotide-binding (G) proteins (Gi)/adenylate cyclase and partially explains the A-II-dependent accentuated antagonism of inotropy.  相似文献   
29.
30.
Three commercial dengue IgM test kits and 'in-house' IgM-capture enzyme-linked immunosorbent assay (ELISA) were examined for false positive reactions, using 49 serum samples from patients with autoimmune diseases. All the samples were found to be negative by the 'in-house' IgM-capture ELISA. Five samples were determined to be positive by the immunochromatographic test and three of the five samples were also found positive by one commercial IgM-capture ELISA kit. These results suggest that a possibility of false positive reaction should be considered when serum samples from autoimmune disease patients are tested for dengue IgM by some commercial dengue IgM test kits.  相似文献   
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