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Relatively nonmyelotoxic drugs and drug combinations were investigated for their ability to eliminate malignant cells from human bone marrow. In vitro 90% inhibitory concentration (IC90) doses were established on granulocyte macrophage colony-forming units (GM-CFU) in culture of bone marrow by using the GM-CFU assay for the following drugs: 4- hydroperoxycyclophosphamide (4-HC), Adriamycin, L-asparaginase, bleomycin, hydrocortisone, VP-16, spirogermanium, Taxol, and vincristine. The leukemic cell kill efficiency of these drugs at IC90 doses was compared with that of 4-HC on acute lymphoid leukemia (ALL) cell lines by using the limiting-dilution assay. Under these conditions, no single drug was superior to 4-HC. To increase the in vitro effect in leukemic cell kill, combinations of vincristine with hydrocortisone, Adriamycin, VP-16, and 4-HC were investigated. Vincristine at 1 to 5 micrograms/mL increased the marrow cytotoxicity of hydrocortisone, Adriamycin, and VP-16, but it was protective (subadditive) with 4-HC. Vincristine and 4-HC in combination was additive to supraadditive on ALL cell lines, increased the leukemic cell kill by one to two logs above 4-HC alone at IC90 doses (P less than .05), and was not affected by the addition of excess marrow cells. The recommended doses for chemopurging in clinical studies are vincristine, 1 to 5 micrograms/mL, plus 4-HC, 5 micrograms/mL.  相似文献   
44.
溃疡性结肠炎(UC)是一种慢性、非特异性炎症性肠病,病因与环境、遗传、感染和肠道微生物等多种因素相关。甘草泻心汤出自《伤寒论》,由炙甘草、黄芩、黄连、干姜、人参、半夏、大枣组成,具有调和寒热,消痞止利的功效。现代研究发现,甘草泻心汤单独或联合西药治疗UC具有显著疗效,其作用机制包括调节炎症因子、保护肠道黏膜和改善肠道菌群。通过查阅相关文献,对近年来甘草泻心汤及其单体治疗UC的相关机制与临床研究进行梳理与总结,以期为中医及中西医结合治疗UC提供理论依据并拓展治疗思路。  相似文献   
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The involvement of the erythropoietin (EPO), plasminogen activator inhibitor type I (PAI1), and multi-drug resistance (MDR2) genes located in chromosomal region 7q21-22 was studied in patients with myeloid disorders and with or without a chromosome 7 abnormality. Separated blood mononuclear cells and granulocytes from 21 patients were used in restriction fragment length polymorphism (RFLP) studies with gene- specific DNA probes. A marked weakness of one of the allelic bands was observed in granulocyte-derived DNA from heterozygous patients with monosomy 7. In four patients with a partial deletion of chromosome 7 long arm (7q-), marked weakness of an allelic band was observed in granulocyte-derived DNA with PAI1 probe (four heterozygous patients) and MDR2 probe (one heterozygous patient), implying deletion of these genes. In contrast, the EPO gene was not deleted in these patients, as demonstrated by the presence of two allelic bands of equal strength in granulocyte-derived DNA (two patients) or by gene dosage estimation (two patients). Two allelic bands of equal strength were also observed in three heterozygous patients with an arbitrary probe (pKV13) located in 7cen-q21.3. Unexpected hemizygosity or hybridization bands were not observed in any patient. We conclude that PAI1 and MDR2 are located distally of EPO in 7q22, and that none of these genes is commonly rearranged in myeloid disorders. The chromosome 7 long arm deletion breakpoint is located in a relatively narrow segment between the PAI1 and EPO genes in different patients. The deletion may involve a specific site in DNA, since the genetic distance between the PAI1 and EPO genes is only 3 cM.  相似文献   
46.
BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) is an important regulator of the chronic inflammation contributing to tumour progression. Infliximab, an anti-TNF-alpha monoclonal antibody was investigated in this trial of patients with advanced cancer. The primary objectives were to determine the safety profile and biological response of infliximab in a cancer population. Clinical response was a secondary objective. PATIENTS AND METHODS: Forty-one patients received infliximab at 5 mg/kg (n = 21) or 10 mg/kg (n = 20) i.v. at 0 and 2 weeks and then every 4 weeks. Post-treatment samples were measured for changes in plasma and serum TNF-alpha, CCL2, IL-6 and C-reactive protein (CRP). RESULTS: Infliximab was well tolerated with no dose-limiting toxic effects. At both doses of infliximab, neutralisation of serum TNF-alpha was observed after 1 h while plasma CCL2, IL-6 and serum CRP were decreased 24 and 48 h following infliximab administration. Seven patients experienced disease stablisation (range 10-50+ weeks). There was no evidence of disease acceleration in any patient. CONCLUSIONS: Infliximab treatment was safe and well tolerated in patients with advanced cancer. There was evidence of biological activity with baseline TNF-alpha and CCL2 being correlated with infliximab response.  相似文献   
47.
Systemic candidiasis with renal involvement is a rare but well-recognized complication during intensive care treatment in very-low-birth-weight infants. We report a term neonate who developed anuria associated with bilateral bezoar formation in the renal pelvis and candidemia. The treatment consisted of placement of a nephrostomy tube in the left kidney, short-term irrigation with amphotericin B and iv, and later, oral administration of fluconazole.  相似文献   
48.
Pelvic ultrasound findings in different forms of sexual precocity   总被引:2,自引:0,他引:2  
Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal–cervical ratio. Ovarian volume was also significantly increased in thelarche and thelarche variant. The fundal–cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty.  相似文献   
49.
Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children.  相似文献   
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