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81.
82.
The objective of this study was to analyse parameters in rhesus monkey collagen-induced arthritis (CIA) with which the inflammation and destruction of the joints can be described in quantitative terms. CIA was induced in genetically susceptible and resistant monkeys, which can be distinguished on the basis of the dominant resistance marker Mamu- A26. The disease course was monitored daily using a semiquantitative scoring system. Plasma samples were collected once or twice weekly and analysed for C-reactive protein (CRP). Urines were collected overnight once a week and analysed for excretion rates of the collagen cross- links hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP). The results show that periods of active CIA are characterized by substantial weight loss and increased plasma CRP levels, followed shortly thereafter by increased excretion rates of the collagen cross- links HP and LP. Remission of the disease can be recognized by a decline in plasma CRP levels and especially an increase in body weight. The highest CRP levels were found in the most severely arthritic monkeys, indicating a possible relationship of the absolute plasma CRP levels to the severity of inflammation. During periods of active arthritis, increased excretion rates of collagen cross-links HP and LP in the urine were found. In particular, the major collagen cross-link in articular cartilage, HP, showed a strong increase (9- to 15-fold). The excretion rates of LP, which is considered as a bone-specific degradation marker, only increased 4- to 6-fold, thus indicating predominant destruction of cartilage and less of bone. In conclusion, the severity of CIA can be monitored in a quantitative manner using plasma CRP levels, urinary excretion rates of HP and LP, and body weights, superimposed on semiquantitative clinical scores. The parameters also facilitate a more objective assessment of the effect of anti-arthritic drugs in the model than with the clinical scores alone.   相似文献   
83.
The purpose of this study was to define, in a phase I study in leukemia, the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of Topotecan, a new topoisomerase I (topo I) inhibitor. Topotecan was delivered by a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 3.5 mg/m2 to 18 mg/m2 per course. Twenty-seven patients were treated, including 17 patients with acute myelogenous or undifferentiated leukemia, 7 with acute lymphocytic leukemia, and 3 with chronic myelogenous leukemia in blastic phase. Severe mucositis was the dose-limiting toxicity occurring in two of five patients treated with Topotecan 11.8 mg/m2 per course; a third patient had prolonged myelosuppression. At the MTD of 10 mg/m2 per course, 1 of 12 patients had severe mucositis and 5 had mild-to- moderate mucositis. Nausea, vomiting, diarrhea, and prolonged myelosuppression were uncommon. Three patients (11%) achieved a complete response, two (7%) had a partial response, and one (4%) had a hematologic improvement. The overall complete plus partial response rate was 19%, and 24% in acute myelogenous or undifferentiated leukemia. A novel in vitro assay that quantifies Topotecan-stabilized topo I-DNA complexes in patient samples was used, which demonstrated heterogeneity in the ability of Topotecan to interact with topo I, the intracellular target of Topotecan. This phase I study defined the MTD of Topotecan to be 10 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Severe mucositis was the dose-limiting toxicity. Future studies will define the precise activity of Topotecan in different leukemia subsets, its efficacy in combination with other antileukemic drugs, and correlations between Topotecan-induced topo I-DNA complex formation and individual patient response to Topotecan.  相似文献   
84.
Although peripheral blood stem cell collections (PBSC) are thought to have less tumor involvement than bone marrow (BM), the incidence of circulating tumor cells in patients with breast cancer has not been widely investigated. We prospectively investigated the incidence and viability of tumor cell involvement in PBSC and BM collections from breast cancer patients undergoing high-dose chemotherapy/hematopoietic stem cell transplantation. Paired samples of PBSC and BM from 48 patients were analyzed using an immunocytochemical technique that detects one epithelial-derived tumor cell per 5 x 10(5) mononuclear cells. Immunostained tumor cells were detected in 9.8% (13/133) PBSC specimens from 9/48 (18.7%) patients and in 62.3% (38/61) BM specimens from 32/48 (66.7%) patients, a significantly higher rate than in PBSC (P < .005). The geometric mean concentration of tumor cells in contaminated PBSC specimens was 0.8/10(5) mononuclear cells (range 0.33 to 2.0/10(5)) compared with 22.9/10(5) mononuclear cells in BM (range 1 to 3,000/10(5), P < .0001). In culture experiments, clonogenic tumor colonies grew in 21/26 immunocytochemically positive specimens. No tumor colony growth was detected in 30/32 immunocytochemically negative specimens. Immunocytochemical detection of tumor involvement in BM and PBSC correlated significantly with in vitro clonogenic growth (P < .0001). We conclude that PBSC contain fewer tumor cells than paired BM specimens from patients with advanced breast cancer and that these tumor cells appear to be capable of clonogenic growth in vitro.  相似文献   
85.
Considerable controversy exists as to the appropriate dosing of heparin for PTCA. We retrospectively reviewed records of 335 patients undergoing PTCA to determine: 1) the effects of correcting for weight and body surface area (BSA) on the heparin dose-response distribution; and 2) the average dose of heparin (standard, weight-based, and BSA-based) required to achieve an activated clotting time (ACT) of 300 seconds. For each patient, height, weight, BSA, baseline ACT (HemoTec), bolus heparin dose, and post-heparin ACT were recorded and the heparin response calculated. There were no significant differences in the distributions of standard (SD =.017 +/- 006 sec/U, 34% of mean), weight-based (SD = 1.41 +/- 0.46 sec/U/kg, 33% of mean), and BSA-based (SD = 0.033 +/- 0.011 sec/U/m2, 32% of mean) heparin response. There were slight, but significant correlations between heparin response and weight (r = 0.37) and heparin response and BSA (r = 0.36). The estimated doses of heparin to achieve a HemoTec ACT of 300 seconds were 10,650 +/- 1270 U, 130 +/- 15 U/kg, and 5390 +/- 640 U/m2. CONCLUSIONS: There are slight but significant correlations between heparin response and both weight and BSA. The distributions of weight- and BSA-corrected heparin response are similar to that of standard heparin dosing. Thus, weight adjusted heparin dosing would not appear to be likely to provide a more reliable ACT response to bolus doses of heparin.  相似文献   
86.
Excluding studies from Brechot and co-workers, little supporthas been found for a role of the hepatitis B virus in the pathogenesisof HBsAg seronegative patients with predominantly chronic liverdiseases, including primary liver cancer. In this study liverDNA from 59 predominantly British patients (four cases withpaired biopsies, 6–12 months apart) with different, mostlychronic, liver diseases was analysed by molecular hybridization.All were seronegative for HBsAg and serum hepatitis B virusDNA (dot blot hybridization) and their liver diseases were believedto be unrelated to hepatitis B virus infection. Hepatitis Bvirus DNA was detected in liver of 11 (18.6 per cent) patients;nine had episomal(3.2 Kb) DNA and eight had higher molecularweight bands suggesting integrated forms. Six patients werealso seronegative for anti-HBc. Patients of UK and non-UK originwere equally represented. Hepatitis B virus DNA was detectedin serum of six of nine patients tested using the polymerasechain reaction. The detection of hepatitis B virus DNA in liverand in serum by this assay in a significant proportion of patientswith chronic liver disease, hitherto unsuspected of being hepatitisB virus-related, suggests a possible role for this virus inlow- as well as high-prevalence countries.  相似文献   
87.
Fifty-one patients with previously untreated or minimally treated chronic myelogenous leukemia in chronic phase received human alpha interferon 3 to 9 X 10(6) units intramuscularly (IM) daily until complete hematologic remission, then at doses ranging from 3 X 10(6) units every other day to 9 X 10(6) units daily. Forty-one (80%) patients achieved a hematologic response, 36 (71%) of them attaining a complete hematologic remission with normal peripheral WBC and differential counts. Responding patients showed continuous but slow normalization of several other blood and marrow parameters including platelet counts, serum lactic dehydrogenase and B12 levels, and marrow cellularity and maturation index. Suppression of the Philadelphia chromosome on serial cytogenetic studies of marrow metaphases was documented in 20 of the 36 patients who achieved complete hematologic remission (56%; 39% of total group), eight of whom (22%) had a decrease of the Philadelphia chromosome-positive metaphases to less than 35%. These changes were persistent for 6 months or longer in 18 patients, seven of whom had continuous suppression of the Philadelphia chromosome to less than 90% for a median of 30+ months (range 21+ to 39+ months). After a median follow-up period of 37 months, 25 patients remain in continued disease control with interferon therapy. The projected 3-year survival rate is 76%, with a yearly death rate of 6%, 9%, and 9% in the first 3 years. Response, Philadelphia chromosome suppression, and survival were significantly better among patients in the low-risk category compared to intermediate- and high-risk categories, as defined by a multivariate analysis-derived prognostic model. The projected 3- year survival rate was 94% for patients who achieved a complete hematologic remission on interferon therapy and 45% for those who did not. Thirteen patients have developed blastic crisis, six with lymphoid and three with undifferentiated morphology. We conclude that human leukocyte alpha interferon effectively controls chronic myeloid leukemia and allows reappearance of diploid hemopoietic cells in some patients.  相似文献   
88.
Neutrophils and monocytes express high levels of PU.1 (Spi-1) but not Spi-B   总被引:9,自引:13,他引:9  
Chen  HM; Zhang  P; Voso  MT; Hohaus  S; Gonzalez  DA; Glass  CK; Zhang  DE; Tenen  DG 《Blood》1995,85(10):2918-2928
  相似文献   
89.
高效液相色谱法测定消痰咳片的含量   总被引:2,自引:0,他引:2  
目的:采用反相色谱法同时测定消痰咳片中两种主要成分甲氧苄啶和磺胺体的含量。方法:以乙腈:0.1%H3PO4(15:85)为流动相,检测波长254nm,HPLC法测定含量。结果:试验表明,甲氧苄啶和磺胺林在0.8-8ug范围内呈良好的线性关系,回归方程分别为Y=-1127.1+110.2x(r=0.9994),Y=-1852.3 256.2x(r=0.9996),相对标准偏差分别为2.1%和0.8%。结论:该方法简便、准确、可靠。  相似文献   
90.
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