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891.
We describe a patient with amyloidosis of renal pelvis and 2 patients with urinary bladder amyloidosis. Clinical presentation in all of the cases mimicked cancer of the respective sites. Clinical diagnosis of amyloidosis is not possible, making biopsy mandatory. Immunology of amyloid formation and treatment of amyloidosis are discussed.  相似文献   
892.
BACKGROUND: Diagnostic imaging of patients in the emergency department offers numerous opportunities for delay. In an era of ED overcrowding, it is important to identify causes of delay in caring for patients to minimize patient length of stay in the emergency department. OBJECTIVES: This study was intended to: (1) identify each of the steps involved in completing emergency diagnostic imaging investigations; (2) identify points of delay in the process; (3) identify the root causes for delay; and (4) perform a barrier analysis to provide insight into the contribution of the work environment and existing processes to delays. METHODS: This prospective, cross-sectional, modified time-in-motion study was conducted simultaneously at 3 urban emergency departments of a Canadian academic center over a 3-week period. Turnaround and process event times were recorded and a log transformation was performed to normalize the time data. Analysis of variance was used to examine individual time intervals between sites. Root cause and barrier analyses were conducted on the summary data. RESULTS: Analysis of 2297 cases revealed the mean turnaround time for one site was 50 minutes and significantly greater (P < .05) than the means of the other 2 sites (approximately 33 and 37 minutes, respectively). Root cause analysis identified 3 root causes of delay: (1) processing of radiograph request order by registered nurse; (2) transport times; and (3) radiology suite location. Barrier analysis indicated that current practices are responsible for the first 2 causes of delay. CONCLUSION: Both radiology and emergency department staffing considerations and workload contribute to delays in turnaround times of diagnostic imaging investigations.  相似文献   
893.
B-1 (CD5+ B) cells appear early in ontogeny, produce mainly unmutated polyreactive antibodies, and are capable of self-renewal. B-1 cells clonally expand with age and are the malignant cell in chronic lymphocytic leukemia. In this report immunological analysis of B-1 malignancies in NZB mice, a murine model of chronic lymphocytic leukemia, is related to current information on B-1 cells. B-1 clones from NZB mice produce high levels of interleukin-10, detected at the RNA level by semi-quantitative polymerase chain reaction. In addition, the B-1 malignant clones in NZB mice and their hybrids, are negative for B220/6B2 expression, the B-specific antigenic form of CD45 which is a membrane-associated phosphatase involved in lymphocyte activation. Both the autocrine production by B-1 cells of interleukin-10 and altered CD45 expression may be responsible for the clonal expansion of these cells, as well as the accompanying T cell expansion. We report the establishment of an in vitro cytotoxic CD8+ T cell line derived from an NZB with a B-1 malignancy. The effect of B-1 cell-derived interleukin-10 on subsets of T lymphocytes may account for the immunoregulatory properties of B-1 cells. In addition, the NZB malignancies were also characterized for immunoglobulin variable region sequence and antigen specificity. The B-1 malignancies produced immunoglobulin derived from unmutated germline sequences with no N base substitutions. It appears that both the immunoglobulin and interleukin-10 produced by the B-1 malignant cell in NZB mice may have immunoregulatory properties. A study of B-1 malignancies may shed light on the immunoregulatory properties of non-clonally expanded normal B-1 cells.  相似文献   
894.
This presentation is a randomized prospective study of 74 patients of squamous cell carcinoma of esophagus divided into two groups. First group was treated with radical radiation alone and the other with radical radiation and combination of bleomycin and 5-FU. Analysis at the end of two years showed that the patients treated with addition of chemotherapy had an overall survival of 23 percent as compared to nine percent in the radiation alone group (P less than 0.05).  相似文献   
895.
896.
A number of newer antibiotics, broad-spectrum penicillins and cephalosporins, have been evaluated against Gram-negative rods. The organisms were selected for multi-resistance and transferable resistance factors. None of the broad-spectrum penicillins was much use against most of the organisms. Ceftriaxone, cefotaxime, latamoxef (moxalactam) and N-formimidoyl thienamycin were all highly effective against most multi-resistant Gram-negative bacilli; cefoperazone being inferior to them. Enterobacter and Serratia strains were relatively resistant to all the agents mentioned and against Acinetobacter only N-formimidoyl thienamycin showed much activity. Thus, use of these drugs may increase the proportion of infections due to organisms such as Serratia or Acinetobacter.  相似文献   
897.
898.
苄基四氢巴马汀(BTHP)使苯福林对大鼠肛尾肌和兔主动脉条作用的累积量效曲线平行右移,最大反应不压低,pA2值分别为5.86和5.8,但对甲氧明和B-HT920升高DP作用的量效曲线无明显影响。BTHP可使异丙肾上腺素和组胺正性频率作用的量效曲线非平行右移,最大反应压低。BTHP还能明显缩短大鼠再灌流所致心律失常的持续时间。结果提示,BTHP对α1受体的阻断及对β和H2受体的非竞争性拮抗作用可能与该药抗心律失常作用有部分关系但并非其主要机理。  相似文献   
899.
The effects of dietary cholesterol and fats on cholesterol metabolism later in life were studied in Mongolian gerbils. Three groups were given a basic diet with soybean oil, palm kernel oil amounting to 8.75% (w/w), or the basic diet only. In three other groups, cholesterol (0.05%) was added to the above diets. Measurements were done in animals of the third generation on the diets. On all diets, teh serum cholesterol of the sucklings was increased as compared to the young that were suckled by mothers on the basic diet only, while body cholesterol was highest in sucklings of mothers on the basic diet or palm-kernel-oil-enriched diets. When the diets were replaced by the basic diets at 6 months of age, serum cholesterol was still increased at 12 months of age in animals previously fed on the cholesterol-enriched diets. Tissue cholesterol did not differ. However, after a challenge with cholesterol at that age, the differences in serum cholesterol were not significantly different.  相似文献   
900.
OBJECTIVE—To review our experience with low dose intravenous pulse cyclophosphamide in the treatment of patients with severe connective tissue diseases.
PATIENTS—Ninety patients (68F:22M) with severe connective tissue diseases received a total of 883 cyclophosphamide pulses with 78 of 90 patients initially having weekly 500 mg pulses for a median of three (2-10) weeks. Diagnoses included: systemic lupus erythematosus (SLE) (n=43); systemic vasculitides (n=42); idiopathic inflammatory myopathies (n=4); mixed essential cryoglobulinaemic vasculitis (n=1). The median age was 48 (range 22-76) years with a median disease duration of 94 (18-250) months.
RESULTS—Complete or partial remission was noted in 68 of 90 patients (75.5%) after a median follow up of 56 (5-213) months. At follow up significant median changes were noted in SLE patients: erythrocyte sedimentation rate (ESR) from 44 to 22 mm 1st hour; anti-dsDNA antibody concentrations from 81 to 48 IU/ml; proteinuria from 2.5 to 1.5 g/day; serum albumin from 36 to 40 g/l; complement C3 from 0.88 to 0.90 g/l, and C4 from 0.18 to 0.22 g/l. In the vasculitis patients significant median changes were seen in: ESR from 44 to 15 mm 1st hour; C reactive protein (CRP) from 16 to 5 g/dl; neutrophils from 8.55 to 4.3 × 109/l; platelets from 340 to 261 × 103/l, and haemoglobin from 12.6 to 13.2 g/dl. Patients with Churg-Strauss syndrome, Wegener's granulomatosis, and neuropsychiatric lupus showed the best initial response but 58% of Wegener's patients relapsed. Median corticosteroid doses were significantly reduced from 15 (5-60) mg to 10 (3-35) mg daily. Adverse events: infections (7 patients), neutropenia (5), lymphopenia (18), and haemorrhagic cystitis (1 intravenous and 2 oral cyclophosphamide), allergies to mesna (2). None of the women at risk had prolonged amenorrhoea. Five patients doubled their serum creatinine and five died from sepsis (2) or severe disease (3).
CONCLUSION—Treatment of severe connective tissue diseases with `low dose' intravenous cyclophosphamide pulses compares in efficacy with the higher monthly doses previously advocated. Treatment was well tolerated with fewer adverse effects and most significantly, there were no cases of premature ovarian failure.

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