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11.
Recent technological advances, in both hardware and software, and availability of various monoclonal antibodies (MoAb) for membrane antigens of blood cells have expanded the application of flow cytometry (FCM) in medicine. In the haematology laboratory, FCM has been used mainly for assessment of leukemia and lymphoma and for determination of lymphocyte subsets. In acute leukemia, FCM is useful to classify ALL accurately, particularly for bi phenotypic or mixed lineage leukemia. In lymphocyte subset determination, we found that the use of magnetic beads to remove contaminating monocytes and some granulocytes to purify the lymphocyte-population is helpful in clarify the subsets. We present data describing the age dependent variation in lymphocyte subsets in the pediatric population. In early life (up to 2 years old), CD4 (+) 2H4 (+) lymphocyte overwhelmed CD4 (+) 2H4 (-) cells, implying predominance of suppressor-inducer activity. We also presented some cases of markedly increased double negative T cells (gamma/delta TCR) and a rare case of double positive (CD4+, CD8+) T cells.  相似文献   
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We report a rare case of neglected fracture dislocation of the second and third carpometacarpal joints, which was treated by arthrodesis of the involved joints.  相似文献   
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Decreased response of beta-adrenergic receptor has been considered to he one of the causes of increased responsiveness of the bronchi in asthma. Since beta-adrenergic receptor has two subtypes, beta1 and beta2, and the bronchodilating effect of beta stimulants is mediated by beta2-receptor, responsiveness of the bronchi is expected to correlate to the cyclic AMP response of lymphocytes to a beta2-stimulant. Responsiveness of the bronchi was expressed as respiratory threshold to acetylcholine (RT-Ach), which was the minimal concentration of acetylcholine solution to cause an initial decrease of FEV1 of more than 20% of the baseline value. Beta1 and heta2-responses were expressed as the increments of cyclic AMP content of 106 lymphocytes incubated with norepinephrine (beta1-stimulant) and salbutamol (beta2-stimulant).
RT-Ach showed a significant correlation with the beta2-cyclic AMP response of lymphocytes, but not with the beta1 -response among patients with asthma. Sixteen symptomatic patients on continuous beta-stimulants showed lower RT-Ach value and diminished beta2-receptor activity of lymphocytes compared with 14 patients in remission. These results suggest that selective beta2-adrenergic blockade may he one of the causes of bronchial hypersensitivity in asthma, though it should be noted that in this study beta-adrenergic responses were examined in lymphocytes and were compared with the responsiveneness of the bronchi. Possible beta-receptor subsensitivity induced by administration of beta-stimulants is discussed.  相似文献   
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Reactions of N-carboxy-α-amino acid anhydride (NCA) with dialkylzinc or related organozinc compounds were studied to elucidate the polymerization mechanism of NCA by dialkylzinc as initiator. The first stage of initiation reaction is a hydrogen abstraction reaction of dialkylzinc from NH group of α-amino acid NCA resulting in the formation of an activated NCA. The second stage of initiation is a reaction between two molecules of the activated NCA forming a zinc carbamate group. Propagation reaction is a carbonyl addition of the zinc carbamate group to the activated NCA to form a mixed anhydride which changes into an amide group releasing carbon dioxide. Regeneration of the activated NCA is supposed to be done by the reaction of free α-amino acid NCA with the zinc atom bonded to nitrogen atom at the growing chain end.  相似文献   
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The effect of a synthetic steroidal anti-androgen, TZP-4238, on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Old male beagle dogs (5-9 years old) were divided into three experimental groups. Group 1 consisted of BPH controls. Groups 2 and 3 received TZP-4238 0.1 mg/kg/day and chlormadinone acetate (CMA) 0.3 mg/kg/day p.o., respectively, for 5 months. In group 1, glandular hyperplasia of the prostate was clearly detected. In contrast, TZP-4238 (Group 2) or CMA (Group 3) produced marked atrophy of the glandular epithelium. In addition, a histopathological study showed that TZP-4238 or CMA medication for 5 months exerted no effect on the testes and the pituitary luteinizing hormone (LH) cells. Therefore, it is suggested that TZP-4238 (0.1 mg/kg) or CMA (0.3 mg/kg) causes regression of spontaneous canine BPH without any histopathological effects on the testes and pituitary LH cells. However, slightly decreased serum testosterone levels were found in TZP-4238-treated animals, due apparently to a direct and/or indirect effect on the testes. Thus, it is suggested that a marginal antigonadotrophic effect cannot be excluded. It is concluded that TZP-4238 is a potent anti-androgen for the treatment of spontaneous canine BPH, without any negative influence on the function of the testes and the pituitary LH cells.  相似文献   
17.
The carcinogenic potential of chloroform was evaluated in a short-term carcinogenicity testing system using CB6F1 rasH2-Tg (rasH2-Tg) mice. Chloroform was administered to rasH2-Tg males at doses of 28, 90, or 140 mg/kg and rasH2-Tg females at 24, 90, or 240 mg/kg by oral gavage for 26 weeks. Wild-type (non-Tg) male and female mice received doses of 140 mg/kg and 240 mg/kg, respectively. N-methyl-N-nitrosourea was administered to rasH2-Tg mice by single intraperitoneal injection (75 mg/kg) as a positive control. In both the rasH2-Tg and non-Tg mice, there was no significant increase in the incidence of neoplastic lesions by chloroform treatment. The incidence of hepatocellular foci in the rasH2- and non-Tg females receiving 240 mg/kg was increased. Forestomach tumors and malignant tumors occurred in most of the rasH2-mice in the positive control group. Swelling or vacuolation of hepatocytes, a toxic change induced by chloroform, occurred in both the rasH2-Tg and non-Tg mice. It is concluded that chloroform, a putative human noncarcinogen, did not show evidence of carcinogenic potential in the present study using rasH2-Tg mice. This study suggests that the rasH2-Tg mouse model may not be appropriate for detecting nongenotoxic carcinogens. However, the sensitivity of rasH2-Tg mice to nongenotoxic carcinogens should be assessed with consideration of the results from the other ILSI-HESI project studies.  相似文献   
18.
Due to the ubiquity of epoxy resin compounds and their potential role in increasing the risk for reproductive dysfunction and cancer, the need for an assessment of human exposure is urgent. Therefore, we developed a method for measuring bisphenol A (BPA) and bisphenol A diglycidyl ether (BADGE) metabolites in human blood samples using high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-MS). Human blood samples were processed using enzymatic deconjugation of the glucuronides followed by a novel sample preparation procedure using a solid-phase-cartridge column. This selective analytical method permits rapid detection of the metabolites, free BPA and a hydrolysis product of BADGE (BADGE-40H) with detection limits in the low nanogram per milliliter range (0.1 ng ml(-1) of BPA and 0.5 ng ml(-1) of BADGE-40H). The sample extraction was achieved by Oasis HLB column on gradient elution. The recoveries of BPA and BADGE-40H added to human plasma samples were above 70.0% with a standard deviation of less than 5.0%. This selective, sensitive and accurate method will assist in elucidating potential associations between human exposure to epoxy-based compounds and adverse health effects.  相似文献   
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