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31.
IL-15 has recently been detected in the synovium of patients with rheumatoid arthritis. IL-15-activated T cells induce significant TNF-alpha synthesis by macrophages via a cell contact-dependent mechanism, suggesting a key regulatory role for IL-15. Here, we report that the administration of a soluble fragment of IL-15Ralpha into DBA/1 mice, profoundly suppressed the development of collagen-induced arthritis. This was accompanied in vitro by marked reductions in Ag-specific proliferation and IFN-gamma synthesis by spleen cells from treated mice compared with control mice and in vivo by a significant reduction in serum anti-collagen Ab levels. These data directly demonstrate a pivotal role for IL-15 in the development of inflammatory arthritis and also suggest that antagonists to IL-15 may have therapeutic potential in rheumatic diseases.  相似文献   
32.
Nitric oxide (NO), produced in large amounts by inducible NO synthase (iNOS), has emerged recently as an important microbicidal and immunomodulatory mediator. We have investigated its role in bacterial septic arthritis caused by Staphylococcus aureus infection using iNOS-deficient mice. The incidence, rate of development, and severity of arthritis were greater in iNOS-deficient than in heterozygous or wild-type control mice. Similarly, the incidence and severity of septicemia and mortality were significantly higher in iNOS-deficient mice compared with controls. Increased TNF-alpha synthesis in vivo and in vitro and enhanced IFN-gamma compared with IL-4 production in vitro in iNOS-mutant mice demonstrated exaggerated Th1 polarization of the host response. These data indicate that high output NO production is not a prerequisite for severe articular destruction and imply that NO is of importance in synovial defense against staphylococcal infection.  相似文献   
33.
Blast cells from a majority of acute myelogenous leukaemia (AML) patients express c-kit mRNA. However, c-kit expression has not been observed in patients with acute lymphoblastic leukaemia (ALL) and lymphoproliferative disease. We report here the detection of an abnormal sized c-kit mRNA in two Hong Kong Chinese patients with pre-B ALL and common ALL.  相似文献   
34.
1. The effects of magnolol, isolated and purified from the cortex of Magnolia officinalis Rehd. et Wils, on thermoregulation and hypothalamic release of 5-hydroxytryptamine (5-HT) by in vivo microdialysis were assessed in normothermic rats and in febrile rats treated with interleukin-1 beta. 2. Intraperitoneal administration of magnolol (25-100 mg/kg) produced a decrease in colon temperature, an increase in foot skin temperature, a decrease in metabolic rate and a decrease in the endogenous release of 5-HT in the rat hypothalamus. 3. Depletion of rat brain 5-HT, produced by intracerebroventricular pretreatment with 5,7-dihydroxytryptamine, attenuated the magnolol-induced hypothermia, cutaneous vasodilation and decreased metabolism. 4. Intracerebroventricular administration of (+/-)-2,5-dimethoxy-4-iodoamphetamine (a 5-HT2 receptor agonist; 5-10 micrograms/5 microL) increased basal colon temperature and reversed the magnolol-induced hypothermia. 5. The increases in both colon temperature and hypothalamic 5-HT release produced by interleukin-1 beta injection were attenuated by treatment with magnolol. 6. The data suggest that magnolol decreases body temperature (due to increased heat loss and decreased heat production) by reducing 5-HT release in rat hypothalamus.  相似文献   
35.
OBJECTIVE: To assess the prevalence of cystinuria and cystine stone disease among families of patients with cystine stones, and to determine their distribution by age, sex and associated morbidity. SUBJECTS AND METHODS: The study comprised 180 relatives (87 males and 93 females, mean age 43 years) descended from two brothers over four generations who live in two areas in northern Jordan. Data were collected using a questionnaire and home visits, by urinary cystine testing and radiology to detect stone, and assessing hypertension and renal impairment. RESULTS: Of the 180 subjects, 104 (58%) had a positive reaction for cystine in urine; 33 (32%) of these were younger than 15 years. Twenty members (11%) of the families had evidence of renal cystine stone disease. Hypertension and renal impairment were detected in a significant proportion of individuals with cystine stone disease. CONCLUSION: Cystinuria is a major risk factor for cystine stone formation. Family screening is valuable in detecting the cystinuric population and in assessing individuals with stones. Early recognition, treatment and counselling result in better management and prevention. The establishment of a cystine study group in our region is essential.  相似文献   
36.
We examined and contrasted morning reports at two hospitals, university and community, that have a pediatric residency program. Patient diagnoses assigned at morning report were compared with final diagnoses to assess disease categories discussed and the value of including outpatient follow-up in this educational forum. Data were obtained during morning reports for 6 months by chief residents at university and private community hospitals. Pertinent history, physical examination, and laboratory and radiologic findings were recorded and were assigned a tentative morning report diagnosis based on morning report discussion. Cases were then reviewed at discharge and at 6 months to determine final diagnoses. At the university hospital, 58% of the cases were undiagnosed before presentation at morning report. Of those cases, 23% were assigned a diagnosis at morning report that differed from the final diagnosis. Similarly, at the private community hospital, 28% of cases were undiagnosed before presentation at morning report. Of those cases, 73% were assigned a diagnosis that differed from the final diagnosis. We conclude that the provision of follow-up at morning report is important for maximizing resident education.  相似文献   
37.
In the present study, we examined the status of the FHIT gene in 112 colorectal cancer and 137 colorectal adenoma specimens. In a total of 5 specimens (4 colorectal cancers and 1 colorectal adenoma), a common smaller product was detected in addition to the normal size product. This smaller product had lost exon 4, the 5' noncoding region of the FHIT gene, owing to alternative splicing. Moreover, all of the 5 tumors with alternative splicing were located lower on the rectum than the anterior peritoneal reflection.  相似文献   
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39.
BACKGROUND: We used dynamic magnetic resonance imaging (MRI) to study breast lesions in 13 women. METHODS: We observed differences in contrast uptake between benignancy and malignancy in 14 suspicious breast lesions. Three-dimensional (3D) gradient echo sequences were obtained before and after administration of gadolinium-based contrast medium (0.16 mmol/kg). The percentage of signal increase in lesions was measured in a series of five 90-second sequences, and time-enhancement patterns were correlated with pathologic diagnoses. RESULTS: Seven benign lesions and three breast cancer recurrences showed less than 185% signal increase at 90 seconds after contrast administration. Three new breast cancers and one recently biopsied benign lesion showed more than 185% signal increase at 90 seconds. CONCLUSION: Using this MRI technique, we can discriminate between new breast cancers (more than 185% early signal increase) and breast cancer recurrence and/or benign lesions (less than 185% early signal increase) but cannot distinguish recurrent from benign lesions.  相似文献   
40.
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