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141.
The purpose of this study is to determine the diagnostic accuracy for detection of culprit lesions in patients with unstable angina. Both ATP 201Tl SPECT and coronary angiography were performed in 51 patients with unstable angina pectoris within a week since the last attack. SPECT images were divided into 17 segments and the regional uptakes were scored semiquantitatively (0 = normal to 3 = no activity) and compared with the coronary angiographic findings. ATP 201Tl SPECT revealed decreased uptakes in 54 of 56 culprit lesions. The sensitivity, specificity and accuracy for detection of culprit lesions were 96.4%, 89.5% and 92.4%, respectively. Although adverse effects during ATP administration were complicated in 28 (54.9%) patients, all the complications were mild and resolved within two minutes. ATP 201Tl SPECT is sensitive and reliable method for detecting culprit lesions and can be performed safely even at acute phase in patients with unstable angina pectoris.  相似文献   
142.
BACKGROUND: To elucidate the intertest agreement of the oxygen uptake efficiency slope (OUES) in comparison with those of the maximal oxygen uptake (VO2max) and the ventilatory anaerobic threshold (VAT). METHODS: Experimental design: A comparative study. Setting: Institutional practice. A total of 19 healthy volunteers underwent two sessions of maximal exercise testing with an interval of no more than 7 days. The testing was conducted on a cycle ergometer with the work rate increased by either 20, 30, or 40 Watts (W)/min so that the subject would reach exhaustion within 9 to 12 min of exercise. VAT was defined as the level of oxygen uptake (VO2) at which either an increase in the ventilatory equivalent for oxygen without a concomitant increase in the ventilatory equivalent for carbon dioxide or a change in the slope of the linear relationship between carbon-dioxide production (VCO2) and VO2 occurred. OUES was determined by the following equation: VO2 = a log VE + b, where VE was minute ventilation and "a" was the OUES. Intertest reproducibility was assessed by coefficient of repeatability (COR). RESULTS: The intertest reproducibility of VO2max and OUES were excellent (COR = 570 ml/min [16%] and 740 [20%], respectively). VAT showed poor agreement between the two tests (COR = 650 ml/min [31%]). CONCLUSIONS: Results show that OUES is reproducible and reliable, supporting the clinical usefulness of this index.  相似文献   
143.
BACKGROUND: Curative resection cannot ensure long-term survival for patients with distal bile duct cancer. The aim of this study was to determine the most frequent mode of recurrence after curative resection and to analyse its risk factors. METHODS: Clinical details for 64 consecutive patients with distal bile duct cancer who underwent surgical resection between 1980 and 1997 were reviewed. Modes of recurrence and clinicopathological findings were analysed based on the residual tumour (R) classification. RESULTS: The overall actuarial 5-year survival rate was 32 per cent. Of 42 patients undergoing R0 resection 10 were alive at 5 years, of 17 having R1 resection one was alive at 5 years, and none of the five patients having R2 resection survived for 5 years (R0 versus R1, P = 0.02). In the R0 group, the incidence of liver recurrence (14 of 42 patients) was similar to that in the R1 resection group (six of 17), although there were fewer lymph node and peritoneal recurrences than in patients who had R1 resection (P < 0.05). The high-risk factor for liver metastasis was microscopic vascular involvement. Important factors for survival were lymph node metastasis, microscopic vascular involvement and age. In addition, microscopic vascular involvement was the only independent factor for survival in the R0 group. CONCLUSION: R0 resection provided significant survival benefit but had no effect on liver recurrence. Therefore, new agents or strategies to prevent liver metastasis are necessary for improvement of survival.  相似文献   
144.
Temperature changes and their distribution induced by 13.56-MHz radiofrequency (RF) heating of agar phantom and porcine and rabbit liver were investigated. It was possible to produce selective local heating of approximately 50 degrees C in the RF field of 2 x 2 x 2 cm(3) of the pig or rabbit liver. Coagulation necrosis after heating became pronounced and the margin between the coagulated lesion and normal tissue became clearer with time. Within 1 week after RF heating at 50 degrees C for 20 min, the coagulated area was replaced selectively and totally by necrotic tissue.  相似文献   
145.
We developed pharmaceutical management and guidance services for inpatients in a ward of circulatory medicine, considering clinical and economical standpoints. In these services, pharmacists deliver drugs prescribed for inpatients with individual drug information papers, explain to them about their drugs using information papers and give counsel. Since most of the patients were aged people, developing many kinds of diseases and taking many kinds of drugs, they had many problems such as lack of knowledge of the effects of drugs. First, we surveyed views of patients, physicians and nurses on these services. Consequently, all of them advised us that "pharmacists should explain to patients about the prescribed drugs using information papers." The patients preferred pharmacists as expositors of drugs to physicians or nurses. The physicians considered that "pharmacists have to attach importance to clinical information and package-inserts of drugs and explain to patients about drug information using pamphlet in response to the understanding of patients." The nurses wanted to cooperate with pharmacists in "improving medication compliance." On the basis of these views, we improved our services. Next, we made a survey of patients' knowledge about their drugs. We found that in the patients the level of knowledge concerning "ways," "effects" and "reasons" of taking drugs and that of "compliance" and "satisfaction in taking drugs" were improved through these services. The patients reentered in the hospital kept a high level. The ratio of patients taking drugs by themselves increased. Last, we also applied this method to wards of "blood and collagen diseases" and "pediatrics." The demand for these services increased smoothly. We compared these services based on our method with all other services by hospital pharmacists from the viewpoint of economy. We found that only our service method was beneficial.  相似文献   
146.
By bioassay-guided fractionation using mushroom tyrosinase (EC 1.14.18.1), 2-hydroxy-4-methoxybenzaldehyde was characterized as the principal tyrosinase inhibitor from three East African medicinal plants, the root of Mondia whitei (Hook) Skeels (Asclepiaceae), the root of Rhus vulgaris Meikle (Anacardiaceae), and the bark of Sclerocarya caffra Sond (Anacardiaceae). It inhibited the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) by mushroom tyrosinase with an ID50 of 4.3 micrograms/ml (0.03 mM). The inhibition kinetics analyzed by a Lineweaver-Burk plot found this simple benzaldehyde derivative to be a mixed type inhibitor for this oxidation and affects on the enzyme in several ways. Based on finding this potent tyrosinase inhibitor, various related analogues were also tested in order to gain new insights into their inhibitory functions on a molecular basis.  相似文献   
147.
To investigate the mechanism of synovial pannus formation in rheumatoid arthritis, immunohistochemical and immunoelectron microscopic studies with monoclonal antibodies against the adhesion molecules, CD54 (ICAM-1), CD 11a (LFA-1), CDw49a (VLA-1), CDw49b (VLA-2), CDw49c (VLA-3), Cdw49d (VLA-4) and CDw49e (VLA-5), were carried out to determine the pattern of distribution of these molecules at the rheumatoid synovial cartilage junction. Treatment with anti-ICAM-1 resulted in membrane staining of most of the macrophages and fibroblasts infiltrating the synovial tissue and bordering the pannus-cartilage junction, suggesting the possibility that ICAM-1 may function to facilitate the adhesion of synovial type A cells bearing ICAM-1 to type B cells of the pannus. ICAM-1-positive macrophages and fibroblasts were often found to be in contact with lymphoid cells, suggesting also that a cellular immune reaction occurs in the formation of the pannus. In addition, VLA-3, VLA-4 and, particularly, VLA-5 were the predominant1 integrins expressed by rheumatoid synovial pannus. Since these three integrins all function as fibronectin receptors, it is possible that the fibronectin-rich environment of the rheumatoid cartilage surface effectively traps pannus cells expressing high levels of these molecules. The VLA-5 molecule was found in a pericellular and interterritorial matrix distribution in the present study, strongly suggesting that a recepfor-ligand interaction between VLA-5 and cartilage matrix may occur at the early stage of pannus formation. Furthermore, an increase in1 integrin may be necessary for the growth of the pannus and also for the upregulation of the VLA molecules, leading secondarily to increased attachment.  相似文献   
148.

Purpose

It is well established that hyperprolactinemia, most typically seen in prolactinoma patients, causes hypogonadism and impotence. There seem to be a good possibility that hyperprolactinemia causes impotence, at least partially via some intrinsic property of prolactin (PRL), rather than through its suppressive effects on the hypothalamic-pituitary-gonadal testosterone dynamics. In the present investigation, we used an in vitro canine model to attempt to clarify whether direct action of PRL on the corpus cavernosum penis may lead to erectile insufficiency. Growth hormone (GH) and placental lactogen (PL), both having close structural and functional homologies to PRL, were also studied.

Materials and Methods

Isometric tension measurement with cavernous strips was performed in the presence or absence of 10 sup -5 to 10 sup -9 M. PRL, GH, or PL in the perfusion medium. The tension change induced by the test substances was normalized relative to that induced by 120 mEq KCl.

Results

Both PRL and GH produced dose-related elevations (p less than 0.01) of the cavernous tension, whereas PL and thiol-cleaved PRL in comparable doses were without effect (p greater than 0.05). When the tension rise produced by 120 mEq KCl was taken as 100 percent, the maximum contractions produced by PRL and GH were 80 percent and 110 percent. The minimum effective concentration was 10 sup -8 to 10 sup -7 M. for both PRL and GH. Pretreatment with indomethacin (10 sup -5 M.), but not tetrodotoxin (10 sup -5 M.), partially suppressed (p less than 0.05) the effects of PRL.

Conclusion

These results suggest that PRL and GH directly and specifically produced contraction of the corpus cavernosum penis, resulting in erectile insufficiency, and that the effect of PRL is partially mediated by prostaglandin.  相似文献   
149.
Two children with intractable fecal incontinence after correction of high anorectal malformations were successfully managed by the daily administration of a glycerin enema into the cecum via an appendicocecostomy or tubularized cecostomy, according to the method of Malone's antegrade continence enema (ACE). Fluoroscopic defecography performed during this procedure in each patient disclosed that the glycerin enema promptly evoked cecal peristalsis, which was transmitted to the distal colon and rectum, and squeezed out almost all the fecal matter, evacuating it from the anus. However, two enemas within a short interval were required to achieve a complete washout of feces. Although this report describes only two patients, our experience confirmed that the ACE was very effective and that adding the word continence to antegrade enema was justifiable. Moreover, fluoroscopic defecography was proven to play a significant role in determining the appropriate regimens of this technique to achieve complete washout of the feces.  相似文献   
150.
A huge phyllodes tumor of the breast that appeared grossly malignant in a 43-year-old woman is described. The patient suffered from a large breast tumor that suddenly increased in size over 5 months to occupy the entire breast. The tumor was hard, ulcerated and 20 cm in greatest diameter. Diagnostic imaging (US, CT and MRI) demonstrated a circumscribed mass with a large cystic cavity. She underwent total mastectomy under a diagnosis of malignant breast tumor. Grossly, the cut surface of the tumor showed a large cystic cavity surrounding a fleshy, hemorrhagic and necrotic mass with a lobulared or trabeculared appearance. Unexpectedly, benign phyllodes tumor (PT) without any stromal overgrowth was diagnosed histologically. She has been doing well since total mastectomy. In our case and in many other reported cases, PT does not show any distinctive correlation between pathologic findings and tumor behavior. Thus wide local excision is the preferred initial treatment for PT.  相似文献   
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