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1.
1. In order to characterize P2-purinoceptor(s) in human urinary bladder the contractile effects of ATP and its slowly-hydrolyzable analogues alpha, beta-methylene ATP (alpha, beta-MeATP) and beta, gamma-methylene ATP (beta, gamma-MeATP) were investigated on human detrusor strips taken from patients undergoing cystectomy for bladder carcinoma. 2. Serial concentration-response curves (SCRC) for ATP, alpha, beta-MeATP and beta, gamma-MeATP were constructed with an interval of 25 min between two successive doses to avoid tachyphylaxis. ATP (10 microM-10 mM) induced a phasic contraction, which was very rapid in onset. The dose-response curve to ATP appeared not to be monophasic: at the lower concentrations (10-300 microM) the curve was shallow, whilst at high concentrations (1-10 mM) the curve was steeper. The magnitude of the response obtained at the highest concentration tested (10 mM) was only 21.1 +/- 2.8% (mean +/- s.e. mean; n = 4) of the KCl (100 mM)-induced contraction. 3. alpha, beta-MeATP (0.3 microM-1 mM) and beta, gamma-MeATP (10 microM-1 mM) elicited a phasic contraction with a time course similar to that exhibited by ATP. The magnitude of the response obtained at the highest concentration tested (1 mM) was 70.3 +/- 6.3% for alpha, beta-MeATP (n = 10) and 27.9 +/- 4.5% for beta, gamma-MeATP (n = 8) of KCl (100 mM)-induced contraction. The rank order of potency was alpha, beta-MeATP > beta, gamma-MeATP > ATP. A plateau of response could not be achieved by any of these agonists.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
A recent study put forward the hypothesis that microlithiasis may represent an early stage in the development of biliary calculi. It is an established fact that cholesterol crystals are the product of an inevitable stage in the sequence leading to gallstone formation. To test the hypothesis stated above ten patients affected by gallbladder cholesterol microlithiasis (CM) were examined in the lipid composition of the bile, the cholesterol saturation index and the presence of cholesterol crystals being calculated. The results were compared with those of 14 patients affected by pigment microliths, 24 with larger stones (LS) and ten control patients. The cholesterol saturation index was above one in all CM patients, whereas in some LS patients the gall-bladder bile was not supersaturated. Cholesterol crystals were observed in the gallbladders of all CM patients and seven LS patients. These results would seem to provide support for the hypothesis of microcalculi as being "young stones", with the bile of CM patients maintaining the conditions leading to gallstone formation.  相似文献   
3.
Fourteen titanium dental implants (Tioblast) were implanted singly in the proximal tibia of New Zealand rabbits for 120 days. A bone defect was surgically produced and filled with Bio-Oss around six of these implants. After the animals were sacrificed and their organs harvested, bone segments were fixed and methacrylate embedded after the push-in test had been performed. Microradiography was performed on longitudinal sections of the implants, whereas scanning electron microscope analysis was performed on the remaining embedded half-implants using secondary electrons only. The results showed that the implants were apically and coronally surrounded by bone, whether Bio-Oss was used or not. Fractures were evident through the newly formed bone and between the pre-existing and newly formed bone. Some fracture lines propagated through the bone and stopped at the implant surface without continuing along the bone-titanium interface. Detachment between the implant and the bone occurred at the coronal extremity of the implants and along its cervical region. These results highlight the fact that the bone-titanium interface has a high resistance to loading. It exhibited greater resistance than the newly formed bone and seems to behave in a manner similar to the cement lines of osteons.  相似文献   
4.
5.
A specific liquid chromatographic (HPLC) procedure is presented for the analysis of nandrolone esters (phenylpropionate, decanoate and undecanoate) in commercial oily injections. The analysis was carried out under isocratic, reversed-phase (RP8 column) conditions using a UV detector (240 nm). The system discriminates between nandrolone alcohol, a potential impurity, and its esters and permits the quantitation of trace benzaldehyde derived from the oxidative degradation of benzyl alcohol. The proposed HPLC method was found to be more specific and accurate than the pharmacopoeial spectrophotometric assay procedure (isoniazid reagent). The interference of benzaldehyde with the isoniazid method was also investigated.  相似文献   
6.
Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 106 IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 106 IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 109 (range, 1–43 × 109), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 106 IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.  相似文献   
7.
Consensus has never been reached regarding the need or the imaging technique for evaluating the common bile duct (CBD) in patients considered for cholecystectomy. With the advent of laparoscopic cholecystectomy there has been a resurgence of interest in the role of preoperative intravenous cholangiography (IVC) as an alternative for evaluating the CBD. The purpose of this audit was to assess whether a diagnostic workup based on IVC, which permits selective use of intraoperative cholangiography (IOC) and endoscopic treatment of CBD stones before surgery, could be useful in patients undergoing laparoscopic cholecystectomy (LC). In patients without jaundice, gallstone pancreatitis, a prior diagnosis of CBD stones, a prior history of contrast allergy, or a risk of contrast-associated acute renal failure, IVC was performed routinely. Patients suspected to have CBD stones based on IVC results or with inconclusive IVC and patients with a strong clinical suspicion of CBD stones were referred for endoscopic retrograde cholangiography (ERC). IOC was carried out in patients who had a history of contrast allergy or risk of contrast-associated acute renal failure and whenever the surgeon was in doubt as to the biliary anatomy or CBD clearance. IVC was carried out in 1155 patients, ERC in 225, and IOC in 54. IVC was conclusive in 1132 patients, with a diagnostic accuracy of 99%. Our workup permitted the sequential endoscopic-laparoscopic treatment of cholecystocholedocholithiasis in 162 cases. During the follow-up period residual CBD stones were detected in four patients. Our diagnostic workup showed that routine IVC exposes the population to a large radiation burden, and the cost is high for the small number of patients who benefit. Moreover, it does not seem helpful in reducing the incidence of CBD injuries during LC.  相似文献   
8.
A male subject exposed for many years to rare earth (RE)-containing fumes and dusts emitted from carbon arc lamps in photoengraving laboratories was investigated to rule out RE pneumoconiosis. While chest x-ray films showed a severe pulmonary fibrosis, clinical analysis showed obvious high RE concentrations in the pulmonary and lymph node biopsy specimens compared with the corresponding tissues of 11 unexposed subjects. In addition to other elements, levels of thorium (Th), which is generally present as an impurity of RE compounds, were also determined to estimate the radiation dose which may be involved in inducing pneumoconiosis. The results show that the levels of Th are more than two orders of magnitude lower than the maximum permissible concentration for occupational exposure to natural 232Th, suggesting that the long-term accumulation of RE in the lungs played a role in the pathogenesis of the observed pulmonary fibrosis of the worker.  相似文献   
9.
Two infants with AIDS who presented with interstitial pneumonitis, failure to thrive, lymphadenopathy, and hypergammaglobulinemia have been studied. Antibody to human T-lymphotropic retrovirus (HTLV-III) was identified by ELISA and Western blot analysis in serum samples from both patients. The T4/T8 ratios of peripheral blood T-lymphocytes in both patients were mildly decreased, with normal absolute numbers of lymphocytes and positive T4 cells. Lung biopsies from both patients demonstrated similar histopathologic features with features of lymphocytic interstitial infiltrates and accumulation of macrophages in the air spaces. Immunoperoxidase studies of the lung biopsy from 1 patient revealed that the lymphocytic infiltrate was composed predominantly of T cells of the T8 subset. Each patient was treated with prednisone, with improvement or resolution of pulmonary symptoms, hepatosplenomegaly, lymphadenopathy, and growth failure. Neither patient has had any opportunistic infections. One patient has been followed for more than 4 years and the other for 8 months.  相似文献   
10.
A new method for isolation and characterization of peptides presented in the context of the nonclassical human leukocytes antigen (HLA) class I molecule HLA-E was developed. A combination of different chromatographic steps coupled with electrospray mass spectrometry allowed us to detect the presence of small amounts of a naturally processed human Cytomegalovirus (HCMV)-derived peptide isolated from the HEK-293T/HLA-E+/UL40+ transfected cells of from HELA cell line. The peptide sequence was confirmed by tandem mass spectrometry (MS/MS). This approach provides a versatile and sensitive method for direct identification of MHC class I-binding peptides that might be derive from different pathogen or tumor-associated proteins.  相似文献   
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