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排序方式: 共有3385条查询结果,搜索用时 15 毫秒
41.
Body surface isochrone mapping was performed in 36 normal subjects and in 85 patients with previous myocardial infarction. Eighty-seven unipolar electrocardiograms distributed over the anterior chest and the back were recorded simultaneously. For each lead, activation time was measured as the time from the onset of QRS to the peak of the R wave. The lead points where R waves were not observed were designated the "no R wave area" (NR area). Isochrone maps of normal subjects had a consistent pattern, with isochrone lines extending from the right upper anterior chest to the left anterior chest and then to the back. NR area was small and was located only on the right upper chest or the upper back. On the isochrone maps of patients with myocardial infarction, abnormal findings were observed; NR area was found in 26 of 28 patients with anterior infarction on the upper to middle anterior chest, in 13 of 22 patients with inferior infarction on the lower chest, and in 24 of 25 patients with anterior and inferior infarction on the upper to lower anterior chest. Activation time was delayed near the NR area (peri-NR area delay) in 37 patients. In patients with apical infarction, an islandlike zone of delayed activation was typically found on the left precordium. These abnormal patterns are considered to indicate local abnormalities in the activation of infarcted myocardium; the NR area indicates dead unexcitable scar, and the peri-NR area delay and islandlike zone of delayed activation indicate partially infarcted myocardium of slow activation. Patients with NR area had greater degree of left ventricular asynergy and lower ejection fraction than those without.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
42.
43.
Summary Clinical characteristics and the outcomes of 50 patients with confirmed subarachnoid haemorrhage (SAH) of unknown aetiology were evaluated. Twenty-nine of these patients were interviewed with a mean follow-up of 7.7 years. Seven patients experienced early rebleeding during hospitalization, and one patient experienced late rebleeding during the follow-up period.On admission to the hospital the consciousness level was clear in 43 of the patients, drowsy in 6, and semicomatose in only 1. Of 10 patients who underwent computerized tomography (CT) within 3 days after SAH, 6 showed no abnormal CT findings and 3 had mild subarachnoid blood. Another patient showed severe SAH. Neurological deficit due to symptomatic vasospasm persisted in only 1 case.Two patients died after re-bleeding during hospitalization, and two others died during the follow-up, thereby representing an overall mortality rate of 8%. Of the latter cases, one died of an unrelated disease, and the other died suddenly from an unknown cause. The remaining forty-six patients (92%) had a good outcome. These results confirm previously reported clinical characteristics, namely that the symptoms of the majority of such cases are mild, the incidence of symptomatic vasospasm is rare, the risk of late re-bleeding is very low (less than 1% per year), and the prognosis is good. The CT findings suggest that some of these features resulted from only mild SAH. Thus, SAH of unknown aetiology seems to be a disease entity with a good prognosis. 相似文献
44.
Kyo E Yokozaki H Yanagihara K Yasui W Ito M Sano T Lee P Saya H Tahara E 《International journal of oncology》1993,3(2):265-271
Wild-type or mutant human p53 gene was transfected into a human gastric carcinoma cell line MKN-1 which shares a mutant p53 allele. Transfected wild-type p53 reduced the colony forming efficiency and tumorigenicity of MKN-1 cells. However, no difference in expression of cell adhesion molecule, oncogenes and growth factors was observed among parent, wild-type p53 and mutant p53 transfectants. In motility assay, the wild-type p53 transfectants relative to the parental or mutant p53 transfectants exhibited a decreased motility, and HGF had a greater effect on the motility of the mutant p53 transfectants, but very little effect on the motility of either the parental or wild-type transfectants. In invasion assay, mutant p53 transfectants revealed the increased invasion ability into collagen gel. These results suggest that allele loss and point mutation of p53 gene may play a critical role not only in growth but also in invasion of gastric carcinoma cells. 相似文献
45.
A Suzuki N Yasui H Hadeishi M Mizuno T Abumiya T Sampei S Nakajima 《Neurologia medico-chirurgica》1990,30(2):95-99
Numerous clinical classification systems have been developed for patients with ruptured intracranial aneurysms. However, most systems do not take age into account and are less reliable in elderly than in younger patients in terms of indications for early surgery and predicting the clinical outcome. The authors have studied this problem using our clinical classification system and, present here the results of 38 elderly patients (greater than or equal to 65 years of age) who underwent neck clipping and implementation of continuous ventricular drainage within 3 days of aneurysm rupture. The clinical outcome at 1 year after onset was considered "good" if the patient was able to function independently and "poor" if he or she was partially or fully dependent or had died. The preoperative level of consciousness was not significantly correlated with the outcome according to Spearman's nonparametric statistical analysis. Age, however, was a significant factor: the incidence of poor outcome was significantly higher in patients over age of 70 years than in those between 65 and 70 (p less than 0.05). Postoperative complications, which were previously found to be significantly related to the outcome in elderly patients, were significantly more common in patients who had a history of cardiac, pulmonary, hepatic, and/or renal disease than in those without such a history (p less than 0.005). The authors found that the prognostic accuracy of clinical classification systems, based on preoperative level of consciousness, is improved in geriatric cases if one point is added for patients over age of 70 years or those with a history of systemic diseases. Additional relevant factors included computed tomographic findings and pre-existing cerebral dysfunction. 相似文献
46.
Hiroyuki Yasui Kiyoshi Yamaoka Terumichi Nakagawa 《Journal of pharmacokinetics and pharmacodynamics》1995,23(2):183-203
A new hepatocellular diffusion model was developed to kinetically evaluate the hepatobiliary transport processes of drugs
in the perfusion system, based on the physiological structure of the liver. Since the equations describing the hepatocellular
diffusion phenomena were derived as image forms in the Laplace domain, the fast inverse Laplace transform (FILT) was adopted
to manipulate the image equations. Cefixime and cefpiramide were selected as model drugs. The concentrations in the perfusate
and the excreted amounts into the bile were simultaneously measured at appropriate intervals after the rapid administration
of each drug into the portal vein. The hepatocellular diffusion model was fitted to the biliary excretion profiles from rat
livers, by means of a nonlinear least squares program, MULTI(FILT). According to this model, the hepatobiliary transport process
of drug is kinetically separated into three steps, that is, the diffusion into and through the hepatocytes, the transfer from
the hepatocytes into the bile canaliculi, and the movement through the bile canaliculi to the outlet of bile duct. These steps
are characterized by the diffusion rate constant through hepatocytes (kdif), the permeability rate constant into the bile canaliculi (kbmc) and the transit time through the bile canaliculi to the outlet of bile duct (
), respectively. It was demonstrated that kdif of cefixime (0.023min1) was significantly smaller than that of cefpiramide (0.044 min1), while the differences in kbmc and
were not obvious between cefixime and cefpiramide. kbmc and
of both drugs were about 1.2 min1 and about 1.0 min, respectively. These parameters were correlated to the excretion ratio into the bile (Fbile) and the mean transit time from the sinusoid through the hepatocytes to the outlet of bile duct (
). 相似文献
47.
In order to elucidate the cause of body weight loss in the early stage of tumor progression, morphological changes of striated muscle were investigated in rabbits every 10 days after VX2 carcinoma implantation. The lean body mass started to decrease in the tumor-bearing rabbits 10 days after implantation, and body fat ratio showed a significant decrease from 30 days, different from the starved rabbits, whose lean body mass and body fat ratio started to decrease from 10 days. Morphological hallmarks of apoptosis in muscle cells were detected in tumor-bearing animals prior to the tumor growth but not in starved animals. These findings suggest that muscle cell apoptosis may be responsible for the body weight loss in the early tumor-bearing. 相似文献
48.
Geographical patterns of excess mortality in Spain explained by two indices of deprivation 总被引:2,自引:2,他引:0 下载免费PDF全文
STUDY OBJECTIVE: To analyse the geographical patterns and the magnitude of the association between deprivation and mortality in Spain. To estimate the excess of mortality in more deprived areas of the country by region. DESIGN: Cross sectional ecological study using 1991 census variables and mortality data for 1987-1992. SETTING: 2220 small areas in Spain. MAIN RESULTS: A geographical gradient from north east to south west was shown by both mortality and deprivation levels in Spain. Two dimensions of deprivation (that is, Index 1 and Index 2) obtained by exploratory factor analysis using four census indicators were found to predict mortality: mortality over 65 years of age was more associated with Index 1, while mortality under 65 years of age was more associated with Index 2. Excess mortality in the most deprived areas accounted for about 35,000 deaths. CONCLUSIONS: Two indices of deprivation strongly predict mortality in two age groups. Excess number of deaths in the most deprived geographical areas account for 10% of total number of deaths annually. In Spain there is great potential for reducing mortality if the excess risk in more deprived areas fell to the level of the most affluent areas. 相似文献
49.
Suzuki T Ogata A Tashiro K Nagashima K Tamura M Yasui K Nishihira J 《Brain research. Brain research protocols》1999,4(3):271-279
We report here an effective and concise method to determine the localization of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, and its mRNA in the central nervous system of pre- and postnatal rats. This method allows for double staining to demonstrate localization of different molecules on the same tissue specimen at the levels of mRNA and proteins by in situ hybridization and immunohistochemistry, respectively. Additionally, the present method gives results more quickly than the conventional isotopic techniques. By use of this method, we carried out immunohistochemistry with an anti-rat MIF polyclonal antibody and demonstrated positive staining using the avidin-biotin complex method (ABC method). To detect its mRNA, we performed nonradioactive in situ hybridization using a digoxigenin (DIG)-labeled RNA probe prepared from a full length fragment of rat MIF cDNA. MIF was strongly expressed in the telencephalon on embryonic day 16. Non-radioactive in situ hybridization with a DIG-labeled RNA probe as well as the immunohistochemistry described here could be applicable to characterize localization of mRNA and proteins of different molecules on the same tissue specimen. 相似文献
50.
Rhabdomyosarcoma of the bladder in an adult 总被引:2,自引:0,他引:2
We report a case of rhabdomyosarcoma of the bladder in an adult. A 73-year-old male was referred to our hospital due to macrohematuria. Ultrasonography, CT and MRI revealed a bladder tumor, and cystoscopic biopsy of the tumor pathologically revealed rhabdomyosarcoma. Total cystectomy with ileal conduit urinary diversion was performed. Copyright Copyright 1999 S. Karger AG, Basel 相似文献