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61.
The basement membrane (BM), a structure of crucial importance in the invasion and metastasis of cancers, was studied immunohistochemically using colorectal cancer tissues. In addition, BM-like structures formed in the primary culture of cancer cells were compared to the BM of primary cancers. BM was stained with antibodies specific for laminin, type IV collagen, fibronectin, and heparan sulfate proteoglycan. In the normal colon these compounds were detected in the glandular BM, vascular BM and perinervium by immunostaining. Components of the BM were not stained in some cancer tissues, and BM staining essentially disappeared in the invasive front of cancer in several cases. Of whole cancer tissues, 10 of 23 cases (43.5%) were BM positive and the remaining 13 cases (56.5%) were negative. A three dimensional primary culture of colorectal cancer cells was performed in collagen gel. The cancer cells obtained from primary cancers which had densely stained for BM formed a BM-like structure in primary culture, but those from negatively stained cancer tissues showed no BM-like structures. The BM-like structure in the primary culture was shown to have the same components as the true BM by immunohistochemistry, and this membranous structure was shown to have originated in the cancer cells. In the primary culture without any BM-like structures, granules containing BM components were observed around tumor cell clusters. The primary culture of tumor cells in collagen gel is closely related to the original tumor tissues and therefore may provide a good model system for the investigation of BM in cancer.  相似文献   
62.
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   
63.
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   
64.
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   
65.
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   
66.
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   
67.
Purpose. The goal of this study was to evaluate the ability of nanoparticles to be used as a targeted delivery system for oligonucleotides. Methods. Pharmacokinetic and tissue distribution were carried out in mice by measuring the radioactivity associated to the model oligothymidylate 33P-pdT16 loaded to poly(isobutylcyanoacryrate) (PIBCA) nanoparticles. In addition, we have used a TLC linear analyzer to measure quantitatively on a polyacrylamide gel electrophoresis, the amount of non degraded pdT16 Results. Organ distribution study has shown that nanoparticles deliver 33P-pdT16 specifically to the liver reducing its distribution in the kidney and in the bone marrow. Nanoparticles could partially protect pdT16 against degradation in the plasma and in the liver 5 min after administration, whereas free oligonucleotide was totally degraded at the same time. Conclusions. Nanoparticles protect oligonucleotides in vivo against degradation and deliver them to the liver.  相似文献   
68.

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   
69.
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   
70.
A multiclinic double-blind controlled study was performed on the effects of MAP in both inpatients and outpatients with AMT as control drug.
  • 1 Subjects consisted of 41 male and 45 female patients suffering from various types of depression. MAP was assigned to 42 cases and AMT to 44 cases. Of these patients, 14 MAP cases and 10 AMT cases were subsequently dropped for a variety of reasons to obtain 28 MAP cases and 34 AMT cases as evaluable.
  • 2 The global improvement ratings were compared and found not significantly different for any week between the two treatments.
  • 3 The global improvement ratings by the characteristic features of patients did not show any significant difference in any items studied between the two treatments.
  • 4 The symptomatic improvement ratings (on the Hamilton R.S. for assessment by the physician) indicated that AMT was more effective on “anxiety (psychic).”
  • 5 The symptomatic improvement ratings (on the Beck self-assessment scale by the patient) indicated that MAP was more effective on “work” and AMT on “pathos”, “feeling of satisfaction”, “withdrawal” and “loss of libido.”
  • 6 During the treatment period, 74.3 percent of the MAP group and 76.9 percent of the AMT group of patients showed some side effects or accompanying symptoms, with no significant difference recognized between the two treatments. Itemwise, however, the incidence of tremor was significantly lower (p-=0.06) in the MAP group. Moreover, the MAP group tended to be less liable to such anti-cholinergic side effects as dry mouth, constipation, trouble of accommodation, urinary disturbance and palpitation.
  • 7 On the basis of the above findings, it is concluded that MAP is as effective against depression as AMT and less liable to the anticholinergic side effects. It is, therefore, a very useful antidepressant.
  相似文献   
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