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91.
92.
Intravenous transplantation of an in vitro maintained murine myeloma cell line, 5T33, results in progressive growth in the bone marrow of C57Bl/KaLwRiJ mice. Concurrent with the growth of the tumor in vivo, the bone marrow stromal cells are inhibited, as assayed by their ability to form stromal cell foci and long-term monolayers in vitro. Inhibition of normal mouse marrow stromal cell growth also occurs when 5T33 cells are added to the marrow cells in vitro, and contact between the marrow and 5T33 cells is not necessary to achieve inhibition, indicating secretion of one or more diffusible inhibitory factors.  相似文献   
93.
钱莉  李伟华 《电子器件》2002,25(4):402-405
对栅MOSFET是一种非常有发展前途的新型器件,它具有跨导高、亚阈值特性优异、短沟道特性好等优点,但是目前自对准的双栅MOSFET的工艺制作相当困难。本文中分析了双栅MOSFET的正、背面栅存在对准误差时,对器件的表态及动态特性的影响,并提出了一种改善这种影响的方法。  相似文献   
94.
Two groups of psoriatic outpatients (ns = 192 and 119) were given, respectively, the Million Clinical Multiaxial Inventory-II and Foulds' Delusions-Symptoms-States Inventory. They were compared with dental (n = 192) and with general surgical (n = 190) patients. The psoriatic group presented clearly higher mean scores and frequencies on most of the personality disorder scales. On Foulds' inventory, psoriatic patients showed higher frequencies of neurotic and psychotic class allocations. A cluster analysis of personality scores provided evidence for 4 different personality clusters of patients with psoriasis: (a) Avoidant, Dependent, Schizoid, and Self-defeating (32.2%), (b) Compulsive, Narcissistic, and Aggressive (30.7%), (c) no personality disorder (18.2%), (d) Borderline, Paranoid, and Schizotypal, etc. (18.8%).  相似文献   
95.
The thermal stability of phenylalanyl-tRNA-synthetase (PTS) from E. coli and T.thermophilus HB 8 was studied in solution at various conditions by scanning microcalorimetry. It has been shown that the value of heating rate, concentration of the enzyme and Mg2+ ions in the solution affects the parameters of thermal denaturation of both enzymes. The higher thermal stability of PTS from T. thermophilus was observed as well as the independence of its properties upon broad variations of experimental conditions. The role of thermostability of the enzymes are discussed with respect to the biological properties of E. coli and T.thermophilus.  相似文献   
96.
OBJECTIVE: To investigate the efficacy, tolerability and safety of cyclosporine A (CSA) in early rheumatoid arthritis (RA) patients. METHODS: Patients with an early diagnosis of RA, a disease duration of less than 3 years, and without prior disease modifying antirheumatic drug (DMARD) treatment were studied. They randomly received oral CSA (3 mg/kg/day) or oral methotrexate (MTX) (0.15 mg/kg/week). In addition, all patients in both groups received oral prednisone (7.5 mg/day). RESULTS: Fifty-two patients were assigned to the CSA group and 51 to the MTX group. After 24 months of treatment, 48 patients from the CSA group and 48 from the MTX group showed significant clinical improvement. This was evaluated by the duration of morning stiffness, grip strength, the total joint count, joint swelling, and joint tenderness and pain, compared to pre-treatment values. The clinical improvement was also associated with a significant decrease in ESR and CRP values in both groups. No significant radiological deterioration was observed in the CSA patients compared to those treated with MTX after 24 months. Four patients from the CSA group dropped out of the study, two because of a synovitis flare, one because of severe hypertrichosis and one because of severe gingival hyperplasia. Three patients from the MTX group withdrew, one because of disease flare-up and two because of gastrointestinal disturbances. CONCLUSION: Early immunointervention in RA patients appears to be crucial to limit the development of joint damage. Cyclosporine A appears to be effective, well tolerated and safe in the long-term treatment of RA and can therefore be used as a first immunomodulatory drug in the armamentarium for the treatment of RA.  相似文献   
97.
98.
Ki-1 large cell anaplastic lymphoma is a recently described variant of malignant lymphoma. A retrospective study of 10 cases of Ki-1 lymphoma was carried out at the Armed Forces Institute of Pathology (AFIP) Rawalpindi to document its clinical and morphological features. The morphological features were evaluated by a study of paraffin embedded sections stained with haematoxylin and eosin stains. Immunohistochemical stains for BER-H2 and leucocyte common antigen (LCA) were performed in all cases. The age of the patients ranged from 2 to 60 years and male to female ratio was 2.3:1. Cervical lymphadenopathy was the most common presentation. Histologically, there was a complete effacement of the lymph node architecture in 8 cases. The Reed-Sternberg like cells were seen in 2 and histiocyte like cells in 7 cases. Immunohistochemically all cases were positive for BER-H2. It is suggested that the possibility of Ki-1 lymphoma should be considered in all cases of lymphoma with pleomorphic morphology.  相似文献   
99.
BACKGROUND: 5-Amino salicylic acid preparations are used in therapy for patients with inflammatory bowel diseases. The bioavailability of these drugs depends on their coating. AIM: To determine whether intraluminal pH is decreased by the presence of inflammation, thereby altering the release of 5-amino salicylic acid in the intestinal lumen. METHODS: Intraluminal gastrointestinal pH was measured by means of a radiotelemetry capsule in 12 healthy controls, in 12 patients with Crohn's disease (five with active disease), and in 11 patients with ulcerative colitis (seven with active disease). RESULTS: The median gastric pH values in the patient groups (Crohn's disease 2.4, range 1.5-4.1; ulcerative colitis 1.95, range 1.55-4.4) were significantly higher than those observed in the controls (1.55, range 0.95-2.6). In the small bowel and colonic segments, all the pH values of Crohn's disease patients were comparable to those of the controls, as were the pH values in the proximal small intestine and in the left colon in patients with ulcerative colitis. However, the latter group had higher pH values in the terminal ileum, the caecum and the right colon. Patients with active disease had comparable median gastrointestinal pH values to patients in remission. CONCLUSIONS: The luminal release of 5-amino salicylic acid might not be inhibited by low pH in patients with active inflammatory bowel diseases. This supports a safe disintegration of the slow release mesalazine preparations even in the presence of severe disease.  相似文献   
100.
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