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51.
Fluconazole monotherapy for cryptococcosis in non-AIDS patients   总被引:3,自引:0,他引:3  
Treatment with 200 to 400 mg/day fluconazole was evaluated in 44 patients without AIDS who had cryptococcosis (19 with cryptococcal meningitis, 22 with pulmonary cryptococcosis, 3 with other cryptococcal infections). For all patients, the clinical response rate was 89% (48% were clinically cured and 41 % clinically improved). Of the patients with cryptococcal meningitis, 89% were mycologically cured. These rates are comparable to those obtained in the treatment of AIDS patients with cryptococcal disease. In the group of patients with cryptococcal meningitis, there was a high rate of agreement between the mycological response to therapy and cryptococcal antigen test results. The use of cryptococcal antigen testing is recommended in all patients with cryptococcosis.  相似文献   
52.
Gefitinib (Iressa, ZD1839), an inhibitor of epidermal growth factor receptor-tyrosine kinase, has shown potent anti-tumor effects and improved symptoms and quality-of-life of a subset of patients with advanced non-small cell lung cancer (NSCLC). However, a large portion of the patients showed no effect to this agent. To establish a method to predict the response of NSCLC patients to gefitinib, we used a genome-wide cDNA microarray to analyze 33 biopsy samples of advanced NSCLC from patients who had been treated with an identical protocol of second to seventh line gefitinib monotherapy. We identified 51 genes whose expression differed significantly between seven responders and 10 non-responders to the drug. We selected the 12 genes that showed the most significant differences to establish a numerical scoring system (GRS, gefitinib response score), for predicting response to gefitinib treatment. The GRS system clearly separated the two groups without any overlap, and accurately predicted responses to the drug in 16 additional NSCLC cases. The system was further validated by the semi-quantitative RT-PCR, immunohistochemistry and ELISA for serological test. Moreover, we proved that the anti-apoptotic activity of amphiregulin, a protein that was significantly over-expressed in non-responders but undetectable in responders, leads to resistance of NSCLC cells to gefitinib in vitro. Our results suggested that sensitivity of a given NSCLC to gefitinib can be predicted according to expression levels of a defined set of genes that may biologically affect drug sensitivity and survival of lung cancer cells. Our scoring system might eventually lead to achievement of personalized therapy for NSCLC patients.  相似文献   
53.
BACKGROUND: The exact mechanism of aspirin-induced asthma is not clear. It has been postulated that precipitation of asthma attacks by aspirin is linked to inhibition of COX activity and massive release of cysteinyl leukotriene into the airway. Tacrolimus, a macrolide-derived immunosuppressant, is used for immunosuppression in organ transplantation and also for allergic diseases such as atopic dermatitis. OBJECTIVE: We evaluated the effects of tacrolimus in aspirin-induced asthma by using a double-blind, crossover study design. METHODS: Twelve patients with aspirin-induced asthma (male:female, 3:9; mean age +/- SD, 36.7 +/- 7.2 years) received either tacrolimus (0.1 mg/kg) or placebo 2 hours before the threshold dose of oral aspirin. RESULTS: In the placebo arm, oral aspirin significantly decreased FEV 1 concomitant with significant increases in sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. Tacrolimus significantly inhibited bronchoconstriction and abrogated aspirin-induced increase in both sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. CONCLUSION: The current study suggested that tacrolimus inhibited bronchoconstriction to a threshold dose of aspirin by inhibition of cysteinyl leukotriene excretion.  相似文献   
54.
We performed electrophysiological study and catheter ablation on a 62-year-old patient with supraventricular tachycardia(SVT). This SVT was reproducibly initiated and terminated by atrial stimulation during the electrophysiological testing. The P-wave morphology and atrial activation sequence of intracardiac electrograms were identical to those in normal sinus rhythm. SVT was terminated with carotid sinus massage that increased vagal tone, and for this reason, the reentry circuit of SVT could be localized in sinus node. On the basis of these findings, the SVT was diagnosed as sinus node re-entrant tachycardia and was successfully eliminated by radiofrequency catheter ablation. Radiofrequency catheter ablation would be effective in patients with sinus node reentrant tachycardia refractory to anti-arrhythmic drugs. It should, however, be performed with careful consideration to the influence of the sinus node.  相似文献   
55.
INTRODUCTION: Orotate phosphoribosyl transferase (OPRT), dihydropyrimidine dehydrogenase (DPD), and thymidylate synthase (TS) are initial key enzymes in the 5-fluorouracil (5-FU) metabolic pathway. The expression levels and activities of these three enzymes play important roles in the response of cancer patients to 5-FU-based chemotherapy. PURPOSE: The purpose of this study was to investigate the relationship between the activities of 5-FU metabolic enzymes and clinicopathologic factors in colorectal cancer. METHODS: We measured the activities of OPRT, DPD, and TS in colorectal cancer tissues. We also investigated the correlations between the activities of these three enzymes and clinicopathologic factors (histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, and vascular invasion). We examined 100 patients with surgically resected colorectal cancer. RESULTS: Poorly differentiated adenocarcinoma showed significantly higher DPD activities than did moderately differentiated or well-differentiated adenocarcinoma. In patients with lymph-node metastasis, OPRT activity was significantly lower than in patients without lymph-node metastasis. No significant relation was found between TS activity and histological type, depth of tumor invasion, extent of lymph node metastasis, Dukes' stage, lymphatic invasion, or vascular invasion. CONCLUSION: The response to 5-FU may be poor in patients with lymph-node metastasis, because of low OPRT activity, and in patients with poorly differentiated adenocarcinoma, because of high DPD activity.  相似文献   
56.
Relationships between leucine-enkephalin fibers and cholinergic neurons in the rat sacral intermediolateral nucleus were examined by light and electron microscopy using double-immunostaining method. Cholinergic neurons in the sacral intermediolateral nucleus were labeled by a rat-mouse monoclonal antibody to choline acetyltransferase and stained bluish green with 5-bromo-4-chloro-3-indolyl-beta-D- galactoside reaction products using beta-galactosidase as a marker. On the same sections, leucine-enkephalin fibers were labeled by a rabbit polyclonal antiserum to leucine-enkephalin and stained brown by diaminobenzidine reaction products using peroxidase as a marker. After embedding in Epon, the sections were examined in light and electron microscopes. In the light microscope, choline acetyltransferase-like immunoreactive cells were seen in the sacral intermediolateral nucleus. In the same region, leucine-enkephalin-like immunoreactive cells. In the electron microscope, 5-bromo-4-chloro-3-indolyl-beta-D-galactoside reaction products were in the form of coarse electron dense deposits in the choline acetyltransferase-like immunoreactive structures and could be distinguished from the much finer grained diaminobenzidine reaction products. Choline acetyltransferase-like immunoreactive neurons received synaptic inputs from leucine-enkephalin fibers-like immunoreactive terminals. These findings suggest that leucine-enkephalin fibers may affect the activity of cholinergic parasympathetic preganglionic neurons.  相似文献   
57.
Genomic DNA from 19 Japanese patients with congenital lipoid adrenal hyperplasia (lipoid CAH) representing 16 different families was examined to identify the genetic alterations of steroidogenic acute regulatory protein (StAR). Ten of 19 patients had a 46,XX karyotype and nine had a 46,XY karyotype. Six of the 46,XX patients have experienced spontaneous pubertal changes including breast development and irregular menstruation whereas none of the 46,XY subjects displayed pubertal changes. Eight different mutations were identified. Sixteen patients were either homozygotes or compound heterozygotes for the Q258X mutation. The seven other mutations identified were 189delG, 246insG, 564del13bp, 838delA, Q212X, A218V and M225T. The 189delG, 246insG, 546del13bp and Q212X mutants encode truncated proteins. COS-1 cells transfected with expression vectors encoding cDNAs for the mutant StAR proteins which affect the C-terminus, 838delA, A218V and Q258X, exhibited no steroidogenesis enhancing activity. However, the M225T mutant retained some steroidogenic activity. The patient with the M225T mutation had late onset of this disorder and some capacity to secrete testosterone in response to hCG. These findings suggest: (i) that the Q258X mutation can be used as a genetic marker for the screening of Japanese for lipoid CAH, (ii) that the C-terminus of StAR plays an important role in the protein's activity and (iii) that there are differences in the extent of functional impairment of the testis and ovaries in lipoid CAH.   相似文献   
58.
A rapid decrease in the number of tumor cells from S180 tumors was caused by several antitumor polysaccharides including the beta (1-3)glucans lentinan and TAK-N and a mannoglucan MGA, but not by those lacking antitumor activity. MGA was demonstrated to induce potent tumor-regressing activity in the serum of tumor-bearing mice similar to that reported previously to be induced after an injection of CM-TAK, a carboxymethylated beta (1-3)glucan. It is probable that the induction of rapid regression of established tumors is a phenomenon common to antitumor polysaccharides and some microbiological products and that the tumor-regressing factor in the serum underlies a common mechanism.  相似文献   
59.
T Nabe  H Yamamura  S Kohno  K Ohata 《Arerugī》1992,41(6):676-685
The anti-allergic action of N-[4-(4-methoxyphenyl)-2-thiazolyl]-1H-tetrazol-5-carboxamide (SA-103) was investigated and compared with that of disodium cromoglycate (DSCG). 1) Oral administration of SA-103 (0.1-10 mg/kg, p.o.) showed dose-dependent inhibition of 48 hr homologous passive cutaneous anaphylaxis (PCA) in rats. The inhibition rate (50%) of the compound at 1 mg/kg was comparable to that of DSCG at 1 mg/kg (i.v.). 2) Both of the drugs concentration-dependently inhibited the release of in vitro anaphylactic histamine from rat peritoneal exudate cells, but SA-103 was 1,000 times as potent as DSCG. 3) High doses (50 and 100 mg/kg, p.o.) of SA-103 tended to suppress 7-day homologous PCA in guinea pigs by only 20-30%. DSCG (100 mg/kg, i.v.) did not influence the reaction. 4) Neither anaphylactic histamine nor leukotriene release from guinea pig lung fragments was markedly influenced by SA-103 (10(-8)-10(-5) g/ml) or DSCG (10(-5)-10(-3) g/ml). 5) The histamine and serotonin induced contractions of the isolated guinea pig ileum were minimally enhanced or suppressed by very high concentrations (10(-4) g/ml) of SA-103 and DSCG. In addition to the above results, prolonged treatment with either compound before antigen challenge decreased the inhibitory response to anaphylactic histamine release from rat peritoneal cells. It is suggested, therefore, that the main mechanism(s) of the anti-allergic action of SA-103 is similar to that of DSCG, and SA-103 may be expected to be effective against allergic diseases.  相似文献   
60.
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