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41.
The effects of sulfobromophthalein (SBP) and ethacrynic acid (ECA), both inhibitors of glutathione S-transferase (GST), or glyceryl trinitrate (GTN)-induced vasorelaxation were investigated in rabbit aortic strips. The aortic strips were pre-contracted with phenylephrine, followed by relaxation with 0.5 microM GTN, with or without 0.1 mM SBP or ECA. ECA was observed to inhibit GTN relaxation approximately 32%, whereas SBP did not alter the GTN activity. The dinitrate metabolites (GDN) of GTN in the tissues were also measured. The amounts of both GDNs were decreased in the ECA-treated, but not the SBP-treated group. Moreover, in the ECA-treated group, a strong correlation was obtained between the loss of GTN activity and the decrease in GTN metabolism. Concentration-response studies also revealed that ECA attenuates GTN relaxation. The slope factor of the concentration-response curves was decreased by ECA, but not by SBP, although both inhibitors caused a mild decrease in Emax. In the 9000 g supernatant of rabbit aorta, ECA was also observed to inhibit GTN metabolism more significantly than SBP. The results suggest that the mechanism of GTN activation may involve a GST isozyme that possesses high activities towards ECA.  相似文献   
42.
One hundred nine Korean American community subjects were interviewed regarding their experiences with hwa-byung (HB), a Korean folk illness label commonly used by Koreans with a myriad of physiological and psychological complaints. During these interviews, standard instruments were also used to assess their depressive and somatic symptoms. The results indicated that a relatively high proportion (12%) of the subjects labeled themselves as having suffered from HB. While no apparent sociodemographic differences were found between HB and non-HB subjects, significantly more HB subjects fulfilled the diagnosis of DSM-III major depression and also had previous diagnoses of depression. The HB subjects also had significantly higher scores for the total, depressive, and somatic subscales and 16 of the 20 individual items of the Center for Epidemiologic Studies-Depression Scale. These data confirm previous observations of substantial overlap between HB and DSM-III major depression among Koreans and Korean Americans, and suggest that HB may be a culturally patterned way of expression for Koreans experiencing major depression and related conditions. The clinical and theoretical implications of these findings are also discussed.  相似文献   
43.
It is well known that brain injury or central traumatic lesions may result in the subsequent appearance of movement disorders such as dystonia or tremor. The concept that peripheral lesions to neural structures may be involved in the pathogenesis of movement disorders has been discussed controversely but has gained more widespread acceptance only recently. Here, we report on 6 patients who developed movement disorders after spinal disc surgery. The movement disorders became manifest with a delay of 1 day to 12 months after surgery. Of the six patients, 4 underwent cervical disc surgery, and 2 patients were operated on for lumbar disc herniation; 2 patients presented with paroxysmal kinesigenic segmental dystonia, 1 patient with focal dystonia, 2 with unilateral tremor, and 1 with bilateral tremor. The appearance of the movement disorder was associated with persistent dermatomal or segmental pain. In all patients, the anatomic distribution of the movement disorder was related to the nerve root or spinal segment of the corresponding disc level and the manifestation was in close temporal relation to the surgery. We conclude that spinal disc surgery may be another, thus far neglected, cause for movement disorders. The postoperative pain syndrome in all patients should be considered as an important factor of pathogenesis. Overall, movement disorders associated with disc surgery appear to be rare, yet they may cause significant discomfort to the affected individual.  相似文献   
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The distinction between seminoma and embryonal carcinoma based on morphology alone can sometimes be problematic, requiring the use of immunohistochemistry to facilitate diagnosis. D2-40 is a monoclonal antibody that reacts with an oncofetal antigen expressed by fetal germ cells and testicular germ cell tumors. The diagnostic value of D2-40 immunohistochemistry in distinguishing seminoma from embryonal carcinoma has not been determined. D2-40 immunoreactivity was evaluated in a series of testicular germ cell tumors and compared with that of KIT (CD117) and CD30, to assess the relative utility of this marker in discriminating between seminoma and embryonal carcinoma. Forty testicular germ cell neoplasms were examined, which included 19 seminomas, three embryonal carcinomas, three teratomas, one yolk sac tumor, and 14 mixed germ cell tumors. The 14 cases of mixed germ cell tumors contained components of seminoma (n=7), embryonal carcinoma (n=11), teratoma (n=10), yolk sac tumor (n=2), and choriocarcinoma (n=1). All cases of pure seminoma and the seminomatous components of mixed germ cell tumors exhibited positive immunoreactivity for D2-40. Focal positivity for D2-40 was also observed in 29% of the embryonal carcinoma samples. D2-40 immunoreactivity in seminomas was characterized by diffuse membrane staining, whereas for embryonal carcinomas, staining was focal and distributed along the apical surfaces of the neoplastic cells. Immunohistochemical staining for KIT was observed in 92% of the seminoma samples and in none of the embryonal carcinomas. Conversely, CD30 expression was identified in 93% of the embryonal carcinoma samples and in none of the seminomas. Other germ cell components showed no immunoreactivity for D2-40, KIT, or CD30. KIT and CD30 are effective immunohistochemical markers in separating seminoma from embryonal carcinoma. Although a highly sensitive marker for seminomas, D2-40 positivity was also observed in a subset of embryonal carcinomas, thus limiting the utility of this antibody for discriminating between these two malignancies.  相似文献   
46.
We report six Chinese boys with hypogammaglobulinaemia. All but one had very low or undetectable circulating B-lymphocytes, two had reversed CD4/CD8 ratios (in one of whom this later became normal), one had reduced lymphocyte proliferative responses to concanavalin A and pokeweed mitogen and three had deficient responses to OKT3. Generation of antibody-secreting cells in response to pokeweed mitogen was markedly defective in all patients. Co-cultures of purified lymphocyte subsets from the patients with those of normal donors revealed that in addition to B-cell deficiency seen in all patients, two had T-helper cell deficiency and two had T-suppressor cell hyperactivity. One of the latter patients was treated with cimetidine in an attempt to ablate histamine type 2 receptor-bearing suppressor cells: the absolute number of such cells was temporarily reduced but there was no concurrent correction of the functional hyperactivity. These studies point to the variable nature of T-regulatory cell deficiencies in hypogammaglobulinaemia.  相似文献   
47.
Ovarian cancers are often diagnosed at a late stage, after the cancer cells have spread to extraovarian sites. Failure to diagnose these tumors earlier may reflect the lack of symptoms and the need for a sensitive, reliable screening test. Alternatively, this can be explained by the hypothesis that some of the extraovarian tumor implants do not represent metastatic spread from the primary cancer but instead are multiple primary tumors developing simultaneously in the peritoneal epithelium. If this is the case, some patients with advanced ovarian cancer may never have had a stage I disease, making early detection theoretically impossible. In this study, we examined the mutational pattern of the p53 gene in 9 patients with epithelial ovarian cancers using tissue collected from different sites within the same patient. In all 9 cases, the mutational pattern of the p53 gene was identical in cancer cells from different sites within the same patient, strongly suggesting that these ovarian tumors were of unifocal origin and that cancer tissues collected from different sites are derived from a single origin.  相似文献   
48.
Background: The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. Methods: We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. Results: The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. Conclusions: With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery.  相似文献   
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50.
The sodium intake of sodium deplete sheep was studied during local, push-pull perfusion of different solutions within the third cerebral ventricle. Sheep were made sodium deplete by continuous loss of parotid saliva, and were allowed access to 0.6 M NaHCO3 solution for 2 h daily. Local perfusion within the third cerebral ventricle was performed before and during the access to sodium solution. Four perfusion sites were used: anterior dorsal and ventral, and posterior dorsal and ventral. Perfusion of 200 mM Na-csf caused a decrease in sodium intake at each perfusion site. Perfusion of ouabain, 10−6M, caused a reduction in sodium intake only during perfusions within the anterior portion of the third ventricle. The results may indicate that specific neuronal elements sensitive to changes in intracellular sodium concentrations are located around the anterior portion of the third cerebral ventricle. These neurones, however, are not exclusive sites from where sodium intake of sodium deplete sheep can be influenced.  相似文献   
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