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51.
In alpha-chloralose-anesthetized Sprague-Dawley (SD) rats with unilateral nucleus tractus solitarius (NTS) lesions, injection of the alpha(1)-adrenergic receptor agonist phenylephrine into the contralateral NTS dose-dependently increased arterial pressure (AP). Bunazosin (0.1 nmol) or prazosin (0.36 nmol), an alpha(1)-adrenergic receptor antagonist, also increased AP. When injected into the NTS, pre-treatment with phenylephrine (10 nmol) or both antagonists abolished the cardiovascular effects of glutamate and acetylcholine. In contrast, pre-treatment with prazosin or methylatropine did not alter the effect of phenylephrine. Phenylephrine (30 nmol) injected into the NTS abolished aortic depressor nerve (ADN) evoked-responses. The pressor effect of phenylephrine in the NTS was exaggerated in spontaneously hypertensive rats (SHR). These results suggest that when injected into the NTS, the effect of phenylephrine may be due to a baroreflex blockade resulting from direct modulatory actions or non-specific neuronal alterations rather than stimulating the alpha(1)-adrenergic receptor. Additionally, this effect is enhanced in SHR.  相似文献   
52.
53.
Human breast cancer MCF-7 cells, growth-arrested by serum starvation, were stimulated with recombinant human insulinlike growth factor-1 (IGF-I). An increase in DNA synthesis was induced 20 hr later, which was as effective as that induced by serum. The increase in DNA synthesis was significantly inhibited either by antibody to the IGF-I receptor or by the tyrosine kinase inhibitor, methyl-2,5-dihydroxycinnamate (2,5-MeC). The IGF-l-induced DNA synthesis coincided with an elevated level of phosphorylation of p53 on tyrosine and an alteration in the subcellular distribution of the protein from the nucleus to the cytoplasm. Whereas the increases in DNA synthesis and p53 phosphorylation were inhibited by antibody to the IGF-I receptor and by 2,5-Mec, the nuclear exclusion of p53 was prevented by the antibody and also, although not significantly, by 2,5-Mec. The results suggest that growth stimulation of MCF-7 cells by IGF-I is accompanied by tyrosine phosphorylation and nuclear exclusion of p53.  相似文献   
54.
Monoclonal antibody KP16D3 recognizes a 60 kDa protein associated with mucin-nonproducing papillary adenocarcinoma, especially that originating from nonciliated bronchiolar epithelial cells of the lung. We immunohistochemically examined 56 primary lung adenocarcinomas using the monoclonal antibody KP16D3. Of these tumors, 31 (55%) were positive for KP16D3 immunoreactivity. The disease-free survival rates showed no statistical differences between KP16D3-positive and KP16D3-negative patients. However, in stage I and T1 disease, the disease-free survival rates of KP16D3-positive patients were statistically lower than those of KP16D3-negative patients (P < 0.05). These findings suggest that KP16D3 may be useful as a prognostic marker for patients with stage I primary lung adenocarcinoma. Conversely, use of this marker and subtyping of lung adenocarcinomas reflect the prognosis of the disease. © 1993 Wiley-Liss, Inc.  相似文献   
55.
Human breast carcinoma MCF-7 cells seeded on type I collagen-coated dishes were provided with an anchor via the collagen receptor, integrin, and grew as actively as those in plastic tissue culture dishes. In contrast, cells seeded on a layer of soft agar became anchorage-deficient and their growth was significantly inhibited, although the cell viability and the cell cycle distribution were unaffected. Immunoprecipitation analysis revealed that mutant p53 was phosphorylated at tyrosine in the anchorage-provided cells. In contrast, the p53 in the anchorage-deficient cells was present in 2-fold greater amount, but was phosphorylated to a lesser extent. Addition of a potent protein-tyrosine kinase inhibitor, herbimycin A, to the anchorage-provided cells caused an elevated level of p53, and inhibitions of cell proliferation and p53 phosphorylation, without interfering with the cell adhesion to the substratum. These results demonstrated that the growth inhibition by anchorage-deficiency or by herbimycin A is associated with an elevated p53 level and reduced p53 phosphorylation at tyrosine.  相似文献   
56.
(+)-布雷菲德菌素A的重要中间体——α、β-不饱和酯(8)可以(1R,2R,2′R)-1-(1′-二甲叔丁硅氧基-2′-羟基乙基)-2-氰基环戊烷(7)为原料,经氧化和Wadworth-Emmons反应制得。  相似文献   
57.
In a 64-year-old man who had been treated with prednisolone (PSL) and 6-mercaptopurine (6MP) for a long period, for ulcerative colitis (UC), hepatocellular carcinoma (HCC) was detected incidentally. The UC was in remission with these medications. After he had been taking these medications for about 8 years, HCC was detected by computed tomography (CT), done for the evaluation of an other disease. Blood chemistry examination results were normal, except that the protein induced by vitamin K antagonist (PIVKA)-II level was 7940 AU/ml. We performed resection of liver segment V. With comparative genomic hybridization, chromosomal aberrations were recognized; these were gains of 1q, 3ptel-21, 8p12, and 22q11.23–22q13.1. Generally, HCC is associated with hepatitis virus infection in most cases, but in this patient, the HCC was not related to hepatitis C virus (HCV) or HBV. It is presumed that this case was related to the immunosuppressive therapy for UC and was associated with the gains of 1q, 3p, and 8p.  相似文献   
58.
BACKGROUND: While rotational acetabular osteotomy has been reported to be successful for the treatment of osteoarthritis of the dysplastic hip, little is known about its efficacy in the treatment of osteonecrosis of the femoral head. METHODS: We retrospectively reviewed the results for a consecutive series of twenty-one patients (twenty-five hips) who had undergone rotational acetabular osteotomy between 1995 and 2001 for the treatment of extensive osteonecrosis of the femoral head associated with collapse. All but two of the patients had a history of steroid therapy as part of a treatment regimen for various diseases. At the time of surgery, the mean age of the five men and sixteen women was 29.0 years. The mean duration of follow-up was forty-nine months. No patient was lost to follow-up. The lesions were classified according to the staging system described by Steinberg et al., and the extent of necrosis was measured with use of the criteria described by Kerboul et al. Clinical evaluation was performed with use of the scoring system of Merle d'Aubigne and Postel. Radiographic evaluation was performed with use of yearly serial anteroposterior and lateral plain radiographs. RESULTS: The mean Merle d'Aubigne and Postel score improved from 11.3 points preoperatively to 14.9 points at the time of the final follow-up (p < 0.001). The mean pain score improved from 3.0 to 5.6 points (p < 0.001). However, the mean mobility score was 5.3 points preoperatively but only 4.9 points postoperatively (p = 0.1). All of the osteotomy sites showed radiographic evidence of osseous union at the time of the latest follow-up. Collapse of the femoral head progressed in seven hips, but in six of these hips the change in the extent of collapse was <2 mm. CONCLUSIONS: In the present study of young patients with extensive osteonecrosis and collapse of the femoral head, rotational acetabular osteotomy was associated with symptomatic relief and absence of substantial collapse of the femoral head at the time of early to intermediate-term follow-up.  相似文献   
59.
OBJECTIVES: In order to clarify the involvement in the nervous system by cervico-brachial disorders (CBD), we performed neurophysiological tests on the peripheral nervous system (PNS) and the central nervous system (CNS) in patients with CBD, subclinicals and healthy controls. SUBJECTS AND METHODS: We employed antidromic sensory nerve conduction velocities (SCV) in the hands and fingers for PNS function and event-related potentials (P300) for CNS higher function. Subjects for SCV were 27 patients, 14 workers with sign and symptoms of CBD (subclinicals) and 22 controls. Subjects for P300 were 23 patients, 12 subclinicals and 10 healthy controls. CONCLUSIONS: In the PNS, since significant reduction SCV in the index finger among patients was observed, we could not find clear evidence of decrease of conduction function. In the CNS, since the latencies and amplitudes of auditory P300 among patients were significantly delayed and decreased, respectively, and the latencies significantly correlated with symptom score, it was suggested that the dysfunction of the cognition and memory function. However, further investigation is necessary to clarify the mechanism.  相似文献   
60.
BACKGROUND: Autonomic neuropathy is a common complication of diabetes mellitus (DM). METHOD: To clarify the relationship between cardiovascular autonomic function and gastric emptying rate, we investigated the gastric emptying and coefficient of R-R interval variation (CV(RR)) of 84 type 2 diabetic patients: 28 cases without peripheral neuropathy and 56 cases with peripheral neuropathy. All patients were subjected to a gastric emptying test according to the marker method (administration of a capsule containing 20 pieces of radiopaque marker during breakfast, followed by abdominal X-ray imaging 3 and 5 h later). Patients had their CV(RR) assessed at rest and during deep breathing. RESULTS: Gastric emptying scores were significantly correlated with CV(RR) during deep breathing and with the duration of DM, but neither age nor CV(RR) at rest in all patients. Gastric emptying scores and CV(RR) at rest and during deep breathing in patients with peripheral neuropathy were significantly deteriorated than those in patients without peripheral neuropathy. A significant correlation between gastric emptying and CV(RR) during deep breathing could be observed in the patients with peripheral neuropathy, but not in those without it. CONCLUSIONS: These findings showed that CV(RR) during deep breathing might be a good indicator of diabetic gastropathy and that peripheral neuropathy was closely related with cardiac and gastric autonomic neuropathy in the type 2 diabetic patients.  相似文献   
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