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81.
1. This paper describes the opioid receptor pharmacology and in vivo activity of several novel benzene-acetamidopiperidine and benzeneacetamidopiperazine analogues. 2. These compounds all showed potent, naloxone-reversible, full agonist activity in the field-stimulated rabbit vas deferens, indicating that they are kappa-opioid agonists; but showed very little activity in the rat or hamster vas deferens, indicating good selectivity with regard to mu- and delta-opioid receptors. 3. They were all potent antinociceptive agents, the most potent compound, GR 103545, having an ED50 value in the mouse abdominal constriction test of 0.25 micrograms kg-1 s.c. The compounds also produced sedation and diuresis, but had little effect on respiration rate or gastrointestinal motility. 4. It is concluded that the seven novel compounds described are all potent and selective agonists for the kappa-opioid receptor.  相似文献   
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1. We studied the effect of bradykinin on plasma exudation in the airways of the anaesthetized guinea-pig in vivo. Tissue content of extravasated Evans blue dye was used as an index of protein exudation in the larynx, trachea, main bronchi and intrapulmonary airways (i.p.a.). 2. Bradykinin increased the content of Evans blue in all tissues studied in a dose-related manner. The response was greatest in the main bronchi and i.p.a., less in the trachea and least in the larynx. A dose of 47 nmol kg-1 was the lowest tested which caused significant (P less than 0.001) plasma exudation with increases in leakage above control values of 256% in the larynx, 405% in the trachea, 394% in the main bronchi and 485% in intrapulmonary airways. 3. Leakage was significantly (P less than 0.05) increased above control values by 1 min after bradykinin (47 nmol kg-1) in the main bronchi and intrapulmonary airways and was maximal in all airways 5 min after bradykinin. Although reduced by 15 min, the tissue content of dye was still significantly (P less than 0.05) increased 2 h after bradykinin. 4. The prolonged tissue dye retention was due to a later phase of slow and maintained exudation preventing full clearance of dye after the initial response. 5. The initial phase of leakage was partially attenuated by the platelet activating factor (PAF) receptor antagonists WEB 2086 or BN 52021, by indomethacin or by inhibiting sensory nerve activation by opioid anaesthesia: it was not affected by mepyramine and cimetidine nor by the sulphidopeptide leukotriene receptor antagonists FPL 55712 or ICI 198,615.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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In the period from January 1, 1976 to December 31, 1988, we reviewed the charts of 33 patients treated for carcinoma of the thyroid at Howard University Hospital. The three non-black patients (two Whites and one Pakistani) were excluded from the study. There were 19 females and 11 males. Of the 30 cases elevated, 10 were papillary, 7 were follicular variant of papillary, 8 were follicular, 3 were undifferentiated (anaplastic), and 2 were medullary. Ten patients had either distant metastasis (Hoffman, South Med J 80:741, 1987) or locally advanced disease in the neck (Woolner et al., Am J Surg 102:354, 1961.) at the time of diagnosis. The treatment of these lesions depended on, among other variables, the cell type, the extent of the lesion, and the personal preference of the attending surgeon. Carcinoma of the thyroid remains an uncommon lesion in Black patients. Because of its rarity, the diagnosis may often be delayed and, as a result, patients may first come to attention with a more advanced stage of this disease. To prevent this occurrence, a high index of suspicion must be maintained for all thyroid nodules, and appropriate diagnostic steps taken. Diagnostic and treatment options are discussed.  相似文献   
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OBJECTIVE We studied the macrolide antibiotic FK-506, an immunosuppressive agent, in an attempt to ameliorate the lesion of autoimmune thyroid disease in human thyroid tissue xenografted into severe combined immunodeficient (SCID) mice. It was not felt appropriate to employ this agent directly in patients with autoimmune thyroid disease because adequate therapeutic modalities are available and the introduction of new, experimental agents could not be justified. Moreover, the study of the tissue before and after treatment could not have been undertaken directly in patients. DESIGN Human thyroid xenografts from four patients with Graves' disease and two normal persons were xenografted into SCID mice. Two weeks after xenograft-ing, human immunoglobulin G (IgG) was detectable in all SCID mice xenografted with Graves' thyroid tissue. Mice were divided into two groups with human IgG levels similar to each other. Mice in the first group were treated with FK-506 daily for 6 weeks; mice in the second (similar) group were given phosphate-buffered saline (PBS) only (control group). MEASUREMENTS Blood samples were taken every 2 weeks from the tail veins for human IgG, thyroid stimulating antibody, thyroperoxidase antibodies, thyroglobulin antibodies, and interferon-gamma (IFN-7). After 8 weeks treatment, animals were sacrificed; thyroid tissue was examined histologically and for thyrocyte HLA-DR expression. FK-506 was also added to thyrocytes in in-vitro tissue culture conditions. RESULTS After 4–6 weeks of FK-506 therapy, human IgG, all thyroid antibodies and IFN-7 were suppressed, while the levels remained elevated in the control group. Lymphocytic infiltration virtually disappeared in the human thyroid tissue of the FK-506-treated mice and thyrocyte HLA-DR expression markedly declined; in the control mice, lymphocytic infiltration remained heavy and HLA-DR expression remained high. On the other hand, FK-506 added directly to thyrocytes in vitro (without lymphocytes) did not reduce thyrocyte HLA-DR expression. CONCLUSIONS FK-506 appears to suppress the activation of intrathyroidal lymphocytes, but not thyrocytes. From these observations, it is concluded that this agent, by its action on intrathyroidal lymphocytes, is able to ameliorate the immunologically mediated histological and serological disturbance in human autoimmune thyroid disease, at least under these circumstances.  相似文献   
87.
Patients with stage T3N0~2M0 gastric carcinoma (n = 108) were studied for relevant prognostic factors. Peritoneal lavage cytology (PLC) was performed in all. In univariate analysis, 5-year survival rates were better with smaller serosal invasion (diameter <3.0 cm vs. ≥3.0 cm, 61% vs. 37%, P < 0.05) and fewer metastatic nodes (≤5 vs. ≥6, 57% vs. 29%, P < 0.05). In multivariate analyses, only these two factors were significant. The predictive value of PLC was not shown in both univariate and multivariate analyses. Peritoneal recurrence occured in 14 (22%) of 77 patients with negative PLC, and in 3 (18%) of 17 with positive PLC, the difference being not significant. Our results indicate that PLC is insensitive in predicting the development of peritoneal recurrence. Its role in the estimation of survival is limited, as many will die of visceral or locoregional recurrence if not of peritoneal dissemination.  相似文献   
88.
Endoscopic resection has been accepted as the standard treatment for intramucosal gastric tumors of differentiated type. However, the indication was limited to small tumors to achieve en bloc resection and prevent local recurrence in cases of conventional endoscopic mucosal resection (EMR) such as the strip biopsy and the cap technique. To avoid multi‐fragmental resection, we have developed endoscopic submucosal dissection (ESD) as a new endoscopic resection technique. ESD is a remarkable technique, because we make it possible to remove the lesions en bloc regardless of size, shape, coexisting ulcer, and location. However, it is difficult or impossible to resect recurrent tumors en bloc in conventional EMR owing to hard fibrosis, and some patients need laparotomy. Using ESD, we can dissect the submucosal layer as we directly look at the submucosa, and remove the lesion safely and reliably even in cases of hard fibrosis. The key to treatment of recurrent tumors in ESD are as follows: (i) using enough submucosal injection solution (we use a mixture of Glyceol and 1% 1900 kDa hyaluronic acid preparation); (ii) incising the mucosa without fibrosis; (iii) understanding characteristics of various cutting devices, and changing other devices in difficult situations. In these ways we can remove the majority of the recurrent tumors en bloc. Hence, we consider that ESD is a very effective treatment which achieves excellent en bloc and complete resection rates and enables patients with intramucosal gastric tumors to a recurrent‐free survival even in recurrent tumors.  相似文献   
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