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91.
92.
Evaluation of myocardial perfusion in the early stage of acute myocardial infarction (MI) is clinically important for adjunctive therapies to minimize infarct size. To determine the role of early scintigraphic detection of impaired myocardial reperfusion after primary coronary angioplasty (PTCA) in patients with acute MI, semiquantitative technetium-99m tetrofosmin single-photon emission tomographic (SPET) imaging was performed before primary PTCA (before; area at risk), 60 min after PTCA (after) and at 1 month (1 M; final infarct) in 35 patients with acute MI. The left ventricle was divided into 13 segments and the defect score was calculated as the sum of the perfusion defect of each segment, from 3 (complete defect) to 0 (normal perfusion). A significant myocardial perfusion change after PTCA was defined as a change in the defect score (before minus after PTCA) of >/=4. The echocardiographic asynergic score was defined as the number of asynergic (severe hypokinetic or akinetic) segments corresponding to the analogous segments on SPET images, and recovery of wall motion was calculated as absolute change in the asynergic score (before PTCA minus 1 M). Among the 35 patients, 15 (43%) had a change in the defect score of <4 (no reflow: group 1) while 20 had a change in the defect score of >/=4 (reflow: group 2). There were no significant differences between the two groups with respect to the time between admission to PTCA, revascularization time, collateral grade or Thrombolysis in Myocardial Infarction (TIMI) flow grade before PTCA. Despite the lack of a difference in area at risk between the two groups (group 1 = 12.8+/-4.3 and group 2 = 15.1+/-4.7), final infarct size in group 1 was significantly larger compared with that in group 2 (8.1+/-4.3 vs 4.9+/-3.0, P<0.001). Recovery of wall motion was significantly smaller in group 1 than in group 2 (4.3+/-1.7 to 3.5+/-1.5 vs 4. 1+/-2.1 to 1.6+/-1.6, P<0.001). In conclusion, a small change (<4) in defect score (scintigraphic no-reflow phenomenon) after primary PTCA indicates persisting impaired myocardial perfusion or irreversible cellular damage just after PTCA which is associated with poor recovery of wall motion, as compared with that observed in cases of reflow (>/=4 in defect score).  相似文献   
93.
94.
BACKGROUND: To explore effective therapeutic strategy against cancer of the gastrointestinal tract, tumor vaccination using fibroblasts secreting interleukin-12 (IL-12) was developed as an adjuvant therapy against murine tumor after surgical resection. METHODS: Initially, IL-12 was genetically engineered into fibroblasts (IL-12/3T3 cells), and then we evaluated in vivo and in vitro antitumor effects. In the vaccination model, irradiated C-26 tumor mass was reinoculated intradermally with IL-12/3T3 cells in mice as a tumor vaccine to examine how much it suppresses tumor recurrence. RESULTS: IL-12/3T3 cells producing 7.2 ng/10(6) cells/24 h murine IL-12 in vitro exerted dose-dependent potent tumor suppression when coinoculated with C-26 cells in vivo. Specific immunity was also acquired in 63% of mice in vivo. In the vaccination model, protective immunity was developed in 70% of mice that were inoculated with irradiated tumor mass and IL-12/3T3 cells. In addition, local recurrence was not observed in vaccinated mice, although 44% of control mice had recurrence. CONCLUSIONS: Coinoculation of genetically engineered fibroblasts secreting IL-12 with irradiated tumor mass was proved to be an effective tumor vaccine. This system of vaccination is easily applicable to clinical situations, particularly to human gastrointestinal tract cancers.  相似文献   
95.
Side-to-side microvascular anastomosis may be required in certain clinical situations, although the technique is difficult and the incidence of usage remains low. A new experimental model using rat femoral vessels for side-to-side microvascular anastomosis is presented, in which 100 percent patency was accomplished immediately and was maintained for 7 days after anastomosis. This model can provide a training tool for acquisition of advanced microsurgical technique for side-to-side anastomosis of small vessels.  相似文献   
96.
Few studies have investigated the relation between glucose tolerance status and ultrasonographically determined gallstone disease. Using a 75-g oral glucose tolerance test, we examined the association of impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) with gallstone disease in Japanese men. Subjects were men aged 48 to 59 of the Japan Self-Defense Forces who received a preretirement health examination between October 1986 to December 1994. After exclusion of 12 men under insulin treatment in the consecutive series of 7637 men, 174 were found to have gallstones; 103 were at the state of postcholecystectomy, and 6899 had normal gallbladder. IGT and NIDDM were associated with a modestly increased risk of gallstone disease; adjusted odds ratios were 1.3 (95% confidence interval [CI]: 0.9–1.8) for IGT and 1.3 (95% CI: 0.8–2.0) for NIDDM after adjustment for hospital, rank, smoking, alcohol use, and body mass index. Adjusted odds ratio for IGT and NIDDM combined was 1.3 (95% CI: 1.0–1.7, p=0.08). When prevalent gallstones and postcholecystectomy were considered separately, NIDDM showed a significant, positive association with postcholecystectomy, but not with prevalent gallstones. The findings add to evidence that glucose intolerance is associated with a modest increase in the risk of gallstone disease.  相似文献   
97.
A new depsipeptide antibiotic, vinylamycin, was isolated from the culture broth of an actinomycete strain. The producing organism, designated MI982-63F1, was identified as a member of Streptomyces. Vinylamycin was isolated from the culture broth by extraction with EtOAc and purified by crystallization from EtOAc. The structure of vinylamycin was determined by spectroscopic analysis and degradation studies. Vinylamycin showed antimicrobial activities against Gram-positive bacteria including MRSA.  相似文献   
98.
New antibiotics designated decatromicins A and B were isolated from the culture broth of Actinomadura sp. MK73-NF4. They were purified by butyl acetate extraction, silica gel column chromatography, silica gel TLC and Sephadex LH-20 column chromatography. Decatromicins A and B inhibited growth of Gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA).  相似文献   
99.

Purpose

Circadian changes in urinary frequency, diuresis and bladder capacity were evaluated in middle-aged and elderly patients.

Materials and Methods

A total of 2,703 urinations from 50 men (median age 66 years) was recorded with a 24-hour uroflowmetry system.

Results

During a 24-hour period the elderly group showed increased frequency and decreased bladder capacity. No difference was observed in diuresis between the 2 age groups. From midnight to 6 a.m. frequency in the elderly group was significantly greater (p less than 0.01) than that in the middle-aged group.

Conclusions

Increased frequency in the elderly group during these hours was primarily due to an increase in diuresis.  相似文献   
100.
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