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71.
The detection of cytokeratins in neoplastic tissues by immunohistochemical methods has numerous diagnostic and investigative applications, because cytokeratins are usually conserved in tumour cells during malignant transformation. Recently, however, it has been reported that progression to malignancy is associated with commencement of expression of low-molecular-weight cytokeratins. In the present study, 42 specimens from 35 cases of squamous cell carcinoma (SCC) of the skin were analysed by immunohistochemical techniques, using polyclonal anti-involucrin antibody and a panel of monoclonal antikeratin antibodies, in order to investigate the nature and differentiation of SCCs. The expression of cytokeratins and involucrin in well-differentiated SCCs was similar to that in normal epidermis. In contrast with well-differentiated SCCs, the expression of differentiation-specific cytokeratins and involucrin was diminished in the immature tumour cells in proportion to the malignancy of the SCCs. Some antibodies, however, stained all tumour cells, irrespective of the degree of malignancy. Furthermore, expression of simple epithelial and non-cornifying stratified squamous epithelial cytokeratins was observed in atypical tumour cells of poorly differentiated SCCs. It is of interest that similar expression was noted in many tumour cells in the lymph node metastases and in some tumour cells in the primary cutaneous lesions. Cytokeratin expression similar to that in normal epidermal keratinocytes was conserved in well-differentiated SCCs, but the expression of cytokeratins changed during progression to malignant transformation. The expression of simple epithelial or non-cornifying stratified squamous epithelial cytokeratins in cutaneous SCCs may be a marker for their capability of invasion and metastatic potential.  相似文献   
72.
This study was designed to elucidate the efficacy of University of Wisconsin (UW) solution for preventing liver injury, when used as a hypothermic perfusate infused into the systemic circulation during extended hepatectomy with hepatic inflow occlusion. Adult mongrel dogs (9.5–17.5 kg, n= 14) were subjected to 75% hepatectomy under 60 min hepatic inflow occlusion. The animals were divided into two groups. The UW group (n= 7) underwent hypothermic perfusion using 4°C UW solution (core temperature of the liver: 12.3±0.2°C). The control group designated as the Ringer's lactate (LR) group (n= 7) underwent hypothermic perfusion using 4°C LR solution. The perfusate was introduced into the systemic circulation via the hepatic vein. Blood from the hepatic vein was sampled, and alanine amino-transferase, purine nucleoside phosphorylase activities and the ammonia concentration were measured. The 7 day survival rate was higher in the UW group than in the LR group. The parameters of liver function were less significantly altered in the UW group than in the LR group. The plasma ammonia concentration was significantly (P<0.05) lower 6h after reperfusion in the UW group than in the LR group. A small volume of hypothermic perfusion of the liver using UW solution was safe if it returned to systemic circulation. Hypothermic perfusion of the liver using UW solution may be effective for preventing hepatic tissue injury during extended hepatectomy with hepatic vascular occlusion.  相似文献   
73.
We investigated whether platelet activation could be quantitatively detected in patients with coronary artery disease using flow cytometric analysis of the expression of CD62P and CD63, which are activation-specific antigens on the platelet surface. Platelet samples were obtained from 16 healthy control subjects and 65 patients, of whom 25 had angiographically normal coronary arteries and 40 had at least one major coronary artery stenosis (≥ 50% narrowing). In both patient groups, CD62P expression was significantly higher than in the control group, but the difference between the two patient groups was not significant. In contrast, CD63 expression did not differ among the three groups. We also compared expression of these antigens after stratifying the patients according to the number of significant coronary artery stenoses. Patients with three-vessel disease had significantly increased CD62P and CD63 expression compared with the other subgroups. Our findings indicate that platelet activation occurs in patients with severe coronary artery stenosis.  相似文献   
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76.
TAKEUCHI, T., et al. : A Case of a Short-Coupled Variant of Torsades De Pointes with Electrical Storm. This case report describes a short-coupled variant of Torsades de Pointes with a characteristic ECG pattern consisting of a prominent J wave in leads V3–V6, in which an electrical storm was evoked with autonomic receptor stimulation and a blockade test. The patient's frequent VF attacks were triggered by short-coupled premature ventricular contractions with a right bundle branch block morphology and left-axis deviation, and were suppressed by deep sedation followed by a combination therapy using verapamil and mexiletine. Interestingly, with the use of those drugs, the prominent J wave diminished. The mechanism underlying this syndrome is discussed. (PACE 2003; 26[Pt. I]:632–636)  相似文献   
77.
Aldo-keto reductase family 1, member B10 (AKR1B10), an enzyme that converts retinals into retinols is known to detect in non-small cell lung carcinoma (squamous cell- and adeno-carcinomas), but is barely expressed in normal tissues. Since these types of carcinoma occur frequently in the uterus (like in the lung), AKR1B10 may also be overexpressed in two major types of uterine cancer, cervical cancer (CC), and endometrial cancer (EMC). The objective of this study is to investigate AKR1B10 expression in uterine cancer and to analyze its clinical significance. In samples from uterine cancer patients, AKR1B10 was detected in 6 out of 30 (20.0%) CC cases and 6 out of 38 (15.8%) EMC cases. Statistical analysis indicated that AKR1B10 expression was associated with tumor recurrence after surgery and keratinization of squamous cell carcinoma only in CC. Although retinol (a metabolic product by AKR1B10) was observed in the normal epithelium, the molecule was not observed in cancer cells of AKR1B10-positive CC samples suggesting that the recurrence in CC may not depend on the convert of retinals into retinols via AKR1B10, a potential indicator in the management of patients with CC.  相似文献   
78.
Pyruvate dehydrogenase complex (PDHC) deficiency is known to cause congenital lactic acidosis. The case of a 9-month-old female infant with PDHC deficiency caused by a mutation in exon 11 of the pyruvate dehydrogenase (PDH) Elα gene is described. Her facial features were as follows: frontal bossing, upslanting palpebral fissures, a short upturned nose, a long philtrum and low set ears. These anomalies are characteristic not only of a malformation syndrome or chromosomal aberration, but also of PDHC deficiency. Because PDHC deficiency requires early treatment, metabolic disorders should be kept in mind in a patient with dysmorphic features. Further, she had multiple minor anomalies including bilateral inguinal herniae, an umbilical hernia and small hands and feet, which have not been described in previous reports.  相似文献   
79.
Accidental transmission of contagious pathogens, especially hepatitis C virus (HCV), by needlestick or other means as an occupational hazard for medical staff is of concern. We retrospectively analysed cases of work-related accidental injury with pathogens such as hepatitis B virus (HBV), HCV, syphilis and human immunode?ciency virus (HIV) reported to the centres for disease control at 15 hospitals (total 5776 beds) in the Gunma prefecture, Japan, from December 1990 to August 1993 (24.7 months). There were 416 such cases (16.8 cases/month), with an incidence of 0.2–3.5 accidents per month per hospital. Such accidents occurred in 297 (71.2%) nurses, 98 (23.5%) medical doctors, 13 (3%) laboratory technicians, four (1.0%) hospital maintenance workers, one (0.2%) assistant nurse, one secretary and two others. There were 323 (77.6%) injuries caused by needlestick, 42 (10.1%) from suture needles or surgical knife cuts, 17 (4.1%) from blood splatters from patients into the eyes or mouth, 10 (2.4%) from contact with injured skin and 24 (5.8%) simple skin contacts. Of the pathogens, 60.3% were HCV, 22.6% HBV, 5.8% syphilis, 0.7% HIV and 10.6% were of unknown origin. Four cases (1.6%) of HCV infection were found and treated with one or two courses of interferon therapy, and HCV was subsequently cleared. All four patients were cured with interferon therapy. None of the HBV-injured cases resulted in infection, possibly because of prophylaxis with HB immunoglobulin and HB vaccine. No HIV or syphilis infection was contracted. In summary, chronic HCV infection acquired as an occupational hazard can be cured by appropriate treatment, such as with interferon, after early detection of the infection.  相似文献   
80.
The in-vitro pharmacological properties of (2,3-dioxo-7-(1H-imidazol-***1-yl)-6-nitro-1,2,3,4-tetrahydro-1-quinoxalinyl)-acetic acid monohydrate, YM872, a novel and highly water-soluble α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)-receptor antagonist were investigated. YM872 is highly water soluble (83 mg mL?1 in Britton-Robinson buffer) compared with 2,3-dihydroxy-6-nitro-7-sulphamoyl-benzo(F)quinoxaline (NBQX), 6-(1H-imidazol-1-yl)-7-nitro-2,3(1H,4H)-quinoxalinedione hydrochloride (YM90K) or 6-cyano-7-nitroquinoxa-line-2,3-dione (CNQX). YM872 potently inhibits [3H]AMPA binding with a Ki (apparent equilibrium dissociation constant) value of 0.096 ± 0.0024 μM. However, YM872 had very low affinity for other ionotropic glutamate receptors, as measured by competition with [3H]kainate (high-affinity kainate binding site, concentration resulting in half the maximum inhibition (IC50) = 4.6 ± 0.14 μm), [3H]glutamate (N-methyl-D-aspartate (NMDA) receptor glutamate binding site, IC50 > 100 μM) and [3H]glycine (NMDA receptor glycine-binding site, IC50 > 100 μM). YM872 competitively antagonized kainate-induced currents in Xenopus laevis oocytes which express rat AMPA receptors, with a pA2 value of 6.97 ± 0.01. In rat hippocampal primary cultures, YM872 blocked a 20-μM AMPA-induced increase of intracellular Ca2+ concentration with an IC50 value of 0.82 ± 0.031 μM, and blocked 300-μM kainate-induced neurotoxicity with an IC50 value of 1.02 μM. These results show that YM872 is a potent and highly water-soluble AMPA antagonist with great potential for treatment of neurodegenerative disorders such as stroke.  相似文献   
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