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Background Interleukin-8 (IL-8) hus been shown to be a chemotactic factor for netitrophils, T-lymphocytes and eosinophils. Repeated intranasal administration of IL-8 enhances bronchial responsiveness to inhaled histamine in guinea-pigs. Neuropeptides which arc released trotn C-fibre nerve-endings have been postulated to induce bronchial hyperresponsiveness through neurogenic inflammation. Objective This study was conducted to examine whether sensory neuropeptides are involved in the IL-8-induced bronchial hyperresponsiveness. Methods IL-8 at a dose of 5μg/kg was administered intranasally to guinea-pigs twice a week for 3 weeks. One day after the last administration, animals were anesthetized and artificially ventilaled through tracheal cannula, and lateral pressure at the tracheal cannula (Pao) was measured as an overall index of airway responses lo increasing concentrations of inhaled histamine (25, 50, 100, and 200 μg/mL). A NKI and NK2 dual antagonist FK224(10mg/kg), a selective NK1 antgonist FK888 (10mg/kg) or vehicle was intravenously administered 10min before measurement of bronchial responsiveness. Result The IL-8 treatment significantly enhanced bronchial responsiveness to histamine (ANOVA P < 0.01). FK224 or FK888 did not alter the IL-8-induced bronchial hyperresponsiveness. Conclusion We conclude that repeated intranasal administratioti of IL-8 causes bronchial hyperresponsiveness (BHR) and that neuropeptides such as neurokinin A and substance P do not directly contribute to the development of BHR induced by IL-8.  相似文献   
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Antiandrogen withdrawal syndrome (AWS) is a well-established phenomenon in prostate cancer. However, responses to AWS are usually of limited duration, and a complete response (CR) is extremely rare. We present two patients who exhibited a chemical CR for more than 2 years after the discontinuation of steroidal antiandrogen chlormadinone acetate use. Whether patients who respond to antiandrogen withdrawal include a group of patients with a better prognosis remains uncertain. However, considering that the usual survival period of patients with hormone-resistant prostate cancer is approximately 12 months, both of the patients reported here, who are present in excellent physical condition, exhibiting an improved quality of life, and attending their hospital as outpatients, obviously acquired a prolonged survival because of AWS.  相似文献   
4.
Background and Aim: Although pretreatment with a sedative drug is effective in relieving pain during esophagogastroduodenoscopy (EGD), such drugs can cause significant side‐effects. The aim of this study was to examine the effect of slow‐wave photic stimulation on discomfort and/or pain felt during EGD. Methods: Forty consecutive patients (25 men and 15 women) who underwent diagnostic EGD in our hospital were included in the study. Twenty patients received photic stimulation for 25 min, and underwent electroencephalographic recording, in addition to the usual premedications. Twenty control patients received the same treatment but without photic stimulation. All patients evaluated the discomfort/pain felt during endoscopy against a five‐grade scale in comparison with what they had experienced in their previous examination. Results: Patients with an improved discomfort/pain score were 18/20 and 3/20 in the treated and control groups, respectively. Overall comparison of pain scores between both groups was significant (P < 0.0001). The proportion of slow‐wave activity recorded in patients’ electroencephalograms significantly increased in the treated group compared to control values (36.6 ± 6.8% vs 29.1 ± 3.4%, P < 0.001). There was a close correlation between the degree of discomfort/pain felt during endoscopy and the proportion of slow‐wave activity (P < 0.001). Conclusion: Slow‐wave photic stimulation shows promise as a treatment for relieving the discomfort and/or pain felt by patients undergoing EGD.  相似文献   
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Interferon (IFN) therapy is of proven efficacy in chronic hepatitis C, but it is not universally effective and is often limited by side effects. Cyclosporine A (CsA) is a potent immunosuppressant widely used in organ transplantation. We conducted a pilot study to determine whether CsA therapy could affect aminotransferase activity and hepatitis C virus RNA levels in patients with chronic hepatitis C. Cyclosporine A was administered to 10 patients (mean age of 59 years; male: female = 9:1) who did not respond to IFN therapy previously and who had elevated serum alanine aminotransferase (ALT) values for at least 6 months. All patients were positive for HCV-RNA by RT-PCR with genotype 1b. Their mean duration of hepatitis was 15 years. Oral CsA was given for 3 months in a dose that was increased at 1 month intervals from 1.5–2.0 to 2.0–3.0 and 3.0–4.0 mg/kg per day. All patients completed the treatment schedule, although two patients developed mild non-symptomatic hypertension. Serum ALT levels gradually decreased in all but one patient. The mean percentage decrease was 59.5% at the end of therapy (from 153 ± 82 to 62 ± 48 IU/L; P < 0.02). The ALT levels fell to the normal range in five patients, although once therapy was discontinued the enzyme levels tended to return to pretreatment levels. Serum aspartate aminotransferase and g-glutamyl transpeptidase levels similarly decreased. The serum HCV-RNA titre, determined by competitive RT-PCR, did not change in any patient throughout the study period. There were no appreciable alterations in other laboratory tests, such as serum creatinine levels and lymphocyte subsets, except for an increase in serum alkaline phosphatase levels. These findings suggest that CsA, even in a relatively low dose, reduces serum aminotransferase levels without serious side effects in patients with chronic-hepatitis C, although an antiviral effect was not noted.  相似文献   
6.
A high-performance liquid chromatographic (HPLC) assay was developed for the determination of trazodone and its metabolite, 1-m-chlorophenylpiperazine (m-CPP), in plasma. The high level of trazodone in plasma was detected by ultraviolet absorbance at 254 nm and the low level of m-CPP in plasma was detected by coulometric electrochemical detection at 840 mV on the series arrangement of two detectors. Pilsicainide as an internal standard for both compounds was monitored by both detectors. Trazodone and m-CPP in plasma were extracted by a rapid and simple procedure based on CN bonded-phase extraction, and C8 reversed-phase HPLC separation. Determination was possible for trazodone in the concentration range 100–2000 ng mL?1 and for m-CPP in the concentration range 5–100 ng mL?1. The recoveries of trazodone and m-CPP added to plasma were 81·0–84·2 and 68·0–73·2%, respectively, with coefficients of variation of less than 7·3 and 8·2%, respectively. The method is applicable to high level monitoring of trazodone and low level monitoring of m-CPP in plasma of healthy volunteers and patients treated with trazodone.  相似文献   
7.
The metabolic behavior, clearance, and pulmonary effects ofgadolinium (Gd), one of the rare earth elements, were investigatedafter single intratracheal instillation of gadolinium chloride(GdCl3) in male Wistar rats. There was a dose-related increasein Gd content of lung tissue. Gd content in the supernatantof bronchoalveolar lavage fluid (BALF) did not exceed 5 µgGd/ BALF even at a dose of 100 µg Gd/rat. Gd in the lungtissue decreased very slowly with a biological half-life of136 days at a dose of 50 µg Gd/rat. On the other hand,Gd content in the super natant of BALF was not detectable after31 days. These results suggest that intratracheally instilledGd can be retained in epithelial lining fluid only to a limitedextent as soluble forms and is deposited in the lung tissueprobably in insoluble forms which are metabolized very slowly.Calcium (Ca) content in BALF increased more rapidly than othertoxicological indices such as lactate dehydrogenase activity,protein concentration, and inflammatory cell counts. In thelung tissue, levels of Ca in Gd-instilled groups did not differfrom the control value. Although these data suggest that theorigin of Ca may be blood plasma, biological and/or toxicologicalsignificance of increased Ca is not known. The number of neutrophilsreached the maximum at 12 hr after instillation, indicatingthat Gd has the potency to cause acute lung toxicity. Summarizingthe observation, Gd instilled intratracheally into rats wasdeposited in the lung tissue in nonsoluble forms with an extremelylong half-life, while the metal caused a rapid and selectiveinfiltration of serum Ca before acute lung toxicity.  相似文献   
8.
土茯苓二氢黄酮醇类成分研究   总被引:12,自引:3,他引:12  
目的 :研究土茯苓的化学成分。方法 :用硅胶、大孔树脂、ODS柱色谱及HPLC方法进行分离纯化 ,根据理化性质和光谱数据进行结构鉴定。结果 :分离鉴定了 5个二氢黄酮醇苷类化合物 ,分别为落新妇苷 (1) ,新落新妇苷 (2 ) ,异落新妇苷 (3) ,新异落新妇苷 (4 ) ,(2R ,3R) 花旗松素-3′-O-β-D-吡喃葡萄糖苷 (5 )。 结论 :化合物 2 ,4 ,5为首次从该植物中分离得到。  相似文献   
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The aim of this study is to assess the different metabolic activities characteristic of glioma recurrence and radiation necrosis (RN) and to explore the diagnostic accuracy for differentiation of the two conditions using 11C-methionine (MET), 11C-choline (CHO), and 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET). Fifty patients with lesions suggestive of recurrent glioma by magnetic resonance imaging (MRI) underwent MET, CHO, and FDG-PET. All patients who had previously been treated with radiotherapy for malignant glioma were subjected to open surgery and pathological diagnosis (17 recurrent grade 3- gliomas (Gr.3s) comprising 7 anaplastic astrocytomas (AAs) and 10 anaplastic oligodendrogliomas (AOs), 17 recurrent glioblastomas (Gr.4s), and 16 RNs). We measured the PET/Gd volume ratio, the PET/Gd overlap ratio, and the lesion/normal brain uptake ratio (L/N ratio) and determined the optimal index of each PET scan. The PET/Gd volume ratio and the PET/Gd overlap ratio for RN were significantly lower than those of glioma recurrence only with MET-PET (P < 0.05). The L/N ratio of RN was significantly lower than that of Gr.4 with all PET imaging (P < 0.001) and was significantly lower than that of Gr.3, especially for AO, only with MET-PET images (P < 0.005). Receiver operating characteristic (ROC) analysis showed that the area under the curve of MET, CHO, and FDG was 92.5, 81.4, and 77.4, respectively. MET L/N ratio of greater than 2.51 provided the best sensitivity and specificity for establishing glioma recurrence (91.2% and 87.5%, respectively). These results demonstrated that MET-PET was superior to both CHO and FDG-PET for diagnostic accuracy in distinguishing glioma recurrence from RN.  相似文献   
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