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991.
R C Ayres S G Hübscher J Shaw C Garner R Joplin A Williams J M Neuberger 《The Journal of pathology》1991,165(2):153-161
We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described. 相似文献
992.
M Arai H Kawada T Kaburagi N Sakai Y Kudou M Kawakami K Konno T Takizawa 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(11):1457-1463
A 40-year-old man who lived in a wooden house built 30 years ago presented with complaints of fever, dry cough and dyspnea. Chest X-ray findings showed interstitial shadows throughout bilateral lung fields. After admission, high-dose administration of 3000 mg of methylprednisolone was performed because of deterioration of chest X-ray shadows and symptoms. In a week, clinical data and symptoms improved. Findings of BAL fluid on admission revealed a relative increase of lymphocytes, neutrophils and mast cells, and pathological findings of transbronchial lung biopsy revealed non-caseous granulation and alveolitis. Precipitating antibodies and indirect fluorescent antibodies against Trichosporon cutaneum and Cryptococcus neoformans had positive reactions and T. cutaneum was isolated and identified from the patient's house. A diagnosis of summer-type hypersensitivity pneumonitis was made according to the criteria advocated by Ando et al. This seemed to be a rare case of summer-type hypersensitivity pneumonitis prolonged after isolation from his normal living environment, successfully treated by high-dose administration of steroid. 相似文献
993.
The classical from of Wegener's granulomatosis (WG) is a necrotizing granulomatous angiitis that involves the upper and lower airways, and kidneys. A limited form of WG is characterized by pulmonary lesions identical to those of classical form WG without renal involvement. The authors report a case of limited form WG. A 58-year-old Japanese woman was admitted because of an abnormal pulmonary shadow. Pathological examination revealed granulomatous angiitis consistent with WG. No other organ involvement was found. The pulmonary shadow improved with cyclophosphamide therapy. The patient is now well and without evidence of exacerbation of the disease 18 month after the discharge. 相似文献
994.
Harvesting the rectus abdominis myocutaneous flap results in defects in both the rectus abdominis muscle and the anterior rectus sheath, which may be circumvented by dissecting a perforator flap (DIEP flap) instead. However, the latter is associated with a reduction in the number of myocutaneous perforators nourishing the flap, which has been hypothesised to lead to an increased risk of partial flap failure. We present a technical modification that maintains all the feeding perforators within the flap while fully preserving the anterior rectus sheath. The anterior rectus sheath is incised along a line connecting the perforators. A muscle cuff including all the feeding perforators was raised with the flap. This technique was used in 20 consecutive patients. Nine patients underwent free TRAM flap transfers for breast reconstruction (10 flaps), and 11 patients underwent thoracic-wall reconstruction with a superiorly based pedicled flap. The median follow-up was 11 months. One patient with a pedicled flap developed a partial failure that required surgical revision; all other flaps healed spontaneously. One patient in each subset had preoperative abdominal-wall laxity that was partly corrected after surgery; no abdominal bulging or hernia occurred in the other patients. Our results suggest that the technical modification presented here may enable the surgeon to dissect a rectus abdominis myocutaneous flap with maximal perforator-related flap perfusion and minimal donor-site morbidity. An advantage over the DIEP flap is that this technique is applicable to both free and pedicled flaps. 相似文献
995.
Previous studies have demonstrated that progressive growth of the weakly immunogenic MCA 106 murine sarcoma stimulated, in the draining lymph nodes, the production of tumor-sensitized but not fully functional preeffector lymphocytes. These lymphocytes could develop into specific immune effector cells after sequential in vitro activation with anti-CD3 monoclonal antibody and interleukin 2 (IL-2). In this study, we analyzed cellular requirements for in vivo sensitization of preeffector cells, for generation of immune effector cells by the method of anti-CD3/IL-2 activation, and for adoptive immunotherapy mediated by activated cells. By selective depletion of T-cell subsets in vivo, we found that tumor regression after systemic adoptive immunotherapy required the collaboration of activated CD4+ and CD8+ cells. It was further demonstrated that CD8+ immune cells alone could mediate antitumor effects if exogenous IL-2 was provided in vivo. These results suggest that CD8+ cells served as immediate effector cells, whereas CD4+ immune cells provided a helper function via the secretion of IL-2. During in vitro anti-CD3/IL-2 activation, generation of effector cells depended on the collaborative interaction between previously sensitized CD4+ and CD8+ preeffector cells. At the stage of in vitro activation, the addition of IL-2 could not substitute the function of CD4+ cells. We next examined whether the sensitization of preeffector cells in the draining lymph nodes required cellular interactions between CD4+ and CD8+ T-cells. By in vivo depletion of T-cell subsets during tumor growth, we found that CD4+ cells were sensitized independently of CD8+ cells. More interestingly, in vivo sensitization of CD8+ preeffector cells also occurred independently in the absence of a CD4+ helper cell response. The lack of T-cell-T-cell interactions in vivo may explain the failure of effector cell generation during progressive tumor growth. Taken together, these results demonstrate that the anti-CD3/IL-2 activation defines an immune response distinct from many previously described mechanisms of antitumor immune responses. 相似文献
996.
F Leonessa V Boulay A Wright E W Thompson N Brünner R Clarke 《Acta oncologica (Stockholm, Sweden)》1992,31(2):115-123
Many breast tumors appear to follow a predictable clinical pattern, being initially responsive to endocrine therapy and to cytotoxic chemotherapy but ultimately exhibiting a phenotype resistant to both modalities. Using the MCF-7 human breast cancer cell line as an example of an 'early' phenotype (estrogen and progesterone receptor positive, steroid responsive, low metastatic potential), we have isolated and characterized a series of hormone-independent but hormone-responsive variants (MIII and MCF7/LCC1). However, these variants remain responsive to both antiestrogens and cytotoxic drugs (methotrexate and colchicine). MIII and MCF7/LCC1 cells appear to mimic some of the critical aspects of the early progression to a more aggressive phenotype. An examination of the phenotype of these cells suggests that some hormone-independent breast cancer cells are derived from hormone-dependent parental cells. The development of a hormone-independent phenotype can arise independently of acquisition of a cytotoxic drug resistant phenotype. 相似文献
997.
Y. Spyckerelle B. Herbeth J.-P. Deschamps ‡ 《Journal of human nutrition and dietetics》1992,5(3):161-168
The dietary history method was used to determine the total energy and macronutrient intake, the distribution of daily energy from the different meals and the energy contribution of various food groups, in a population of 299 boys, aged between 10 and 15 years. The effects of age, the social status of the father (SPS), the ponderal index, the importance of breakfast or lunch, and the level of energy intake on dietary indicators, were studied. In our population, energy intake increased with increasing age but the energy contribution of macronutrients did not vary. The diet of boys whose fathers were in the upper SPS classes differed from the diet of those boys whose fathers were manual workers: for example they consumed less energy and pastries, but more animal protein (in percentage of energy intake), more dairy products, and more fruit. The ponderal index was negatively related to energy intake but positively related to protein intake, especially from meat and meat products. The energy intake from protein, animal protein and the energy contribution of dairy products, meat and meat products, fish and vegetables was lower among large eaters than among small eaters. The energy contribution of pastries, sugar and sweets was higher among large eaters.
Similarily, the energy intake from morning and evening snacks was also higher among large eaters. It should be noted that boys who had a substantial breakfast took in less energy from all other meals (including snacks and main meals). Such informaton is necessary in order to develop an effective health programme. 相似文献
Similarily, the energy intake from morning and evening snacks was also higher among large eaters. It should be noted that boys who had a substantial breakfast took in less energy from all other meals (including snacks and main meals). Such informaton is necessary in order to develop an effective health programme. 相似文献
998.
D B White C A Walawander D Y Liu T H Grasela 《Journal of pharmacokinetics and biopharmaceutics》1992,20(3):295-313
In a simulation study of inference on population pharmacokinetic parameters, two methods of performing tests of hypotheses comparing two populations using NONMEM were evaluated. These two methods are the test based upon 95% confidence intervals and the likelihood ratio test. Data were simulated according to a monoexponential model and, in that context, power curves for each test were generated for (i) the ratio of mean clearance and (ii) the ratio of the population standard deviations of clearance. To generate the power curves, a range of these parameters was employed; other pharmacokinetic parameters were selected to reflect the variability typically present in a Phase II clinical trial. For tests comparing the means, the confidence interval tests had approximately the same power as the likelihood ratio tests and were consistently more faithful to the nominal level of significance. For comparison of the standard deviations, and when the volume of information available was relatively small, however, the likelihood ratio test was more able to detect differences between the two groups. These results were then compared to results on parameter estimation in order to gain insight into the question of power. As an example, the nonnormality of estimates of the ratio of standard deviations plays an important role in explaining the low power for the confidence interval tests. We conclude that, except for the situation of modeling standard deviations with only sparse information, NONMEM produces tests of significance that are effective at detecting clinically significant differences between two populations. 相似文献
999.
Xiao Er Ke Chuan Ling Oral Liquid (KCL) is a Chinese herbal preparation consisted of 10 herbs such as Prunus armeniacae, Scutelaria baicalensis, Lonicera japonica etc. 30 children suffering from bronchopneumonia and/or acute bronchitis were treated with KCL (treated group) and another 30 cases were treated with penicillin and aminophylline (control group). Results: cure rate and effective rate in treated group was 26.6%, and 93.3% respectively. While in control group was 30% and 96.6% respectively. No significant differences were seen between them(P > 0.05). The pharmacodynamic experiment showed KCL had potent pharmacological action. The experiment on tracheal fragment of Guinea pig in vitro showed it caused moderately strong smooth muscle relaxation, through inhibition the effect of histamine and acetylcholine. Asthma induction experiment of Guinea pig in vivo showed KCL could significantly prolong the latent period of asthma and alleviate asthmatic symptom. Ammonium water cough induction experiment in mice showed it may apparently prolong cough latent period and reduce times of cough relapse and alleviate cough symptom. KCL had potent antipyretic effect on fever model induced by triple vaccine in rabbits. Bacteriostatic and antiviral experiment in vitro showed the drug had quite strong inhibitory effects for Streptococcus hemolyticus, Staphylococcus aureus, Flexners Dysentery bacillus, Diplococcus pneumoniae and Pseudomonas aeruginosa, and it could potently inhibit the respiratory syncytial virus. KCL is an effective drug in treating bronchopneumonia and acute bronchitis. 相似文献
1000.
Himalayan rabbits immunized with homogenates prepared from nymphs of Amblyomma hebraeum Koch and A. marmoreum Koch ticks developed humoral and probably also cell-mediated immunity to their respective homogenates. Beta and gamma globulin levels and numbers of eosinophils and neutrophils increased significantly in inoculated rabbits. The recipient animals developed resistance to homospecific nymphal infestations. Cross resistance between the two species was not evaluated. Nymphs of both species that fed on inoculated rabbits demonstrated slightly shorter feeding periods, and their mean weights were significantly lower than nymphs that fed on Quil 'A' adjuvant-inoculated rabbits or on naive rabbits. Significantly higher proportions of nymphs from immunized animals failed to moult when compared with nymphs that fed on the two control groups. These parameters indicate that the inoculated rabbits had acquired protective immunity against nymphs of both ticks. 相似文献