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81.
The administration of moderate to high doses of corticosteroids is associated with bone loss. This probably results from the uncoupling of bone formation (decreased) and bone resorption (unchanged or increased). We examined the effect of low-dose (10 mg/day) prednisone (LDP) and the possible mitigating effects of calcium and 1.25 (OH)2 vitamin D (calcitriol) on calcium and bone metabolism in eight healthy, young male volunteers. The study consisted of four observation periods: in the first period, LDP was prescribed during 1 week; in the second, third and fourth periods, calcium (500 mg/day), calcitriol (0.5 micrograms b.i.d.) and calcium in combination with calcitriol, respectively, were added to LDP. Bone formation was measured by means of serum osteocalcin, carboxy-terminal propeptide of type 1 procollagen (P1CP) and alkaline phosphatase, bone resorption by means of urinary excretion of calcium, hydroxyproline, (free and total) pyridinoline, (free and total) deoxypyridinoline and serum carboxy-terminal cross- linked telopeptide of type 1 collagen (1CTP). Dietary calcium and sodium intake were maintained at a stable level during the entire study period. Treatment with LDP led to a decrease in osteocalcin, P1CP and alkaline phosphatase (all P < 0.01). Urinary excretion of pyridinolines, hydroxyproline and serum 1CTP did not increase, but remained unchanged or slightly reduced (P < 0.05), depending on the time of measurement and the marker of bone resorption. Parathyroid hormone (PTH) (insignificantly) increased during LDP (+19%) and LDP plus calcium (+14%), but decreased during supplementation with calcitriol (-16%) and calcium/calcitriol (-44%; P < 0.01). Urinary excretion of calcium increased during treatment with LDP and calcitriol (P < 0.05) and calcium/calcitriol (P < 0.05). It is concluded that LDP has a negative effect on bone metabolism, since bone formation decreased while bone resorption remained unchanged or decreased slightly. The increase in PTH during LDP could be prevented by calcitriol combined with calcium supplementation.   相似文献   
82.
Autologous stem cell transplantation with or without in vitro lymphocyte depletion has been suggested as a new treatment option for severe autoimmune diseases. We describe five patients with autoimmune diseases (CREST syndrome, myasthenia gravis and Hashimoto's thyroiditis, systemic lupus erythematosus, atopic dermatitis, and rheumatoid arthritis) who underwent autologous bone marrow (n = 1) or peripheral blood progenitor cell (n = 4) transplantation with unmanipulated grafts as treatment for the autoimmune disease in one case or as treatment for a malignant disorder with a concomitant autoimmune disorder in four cases. In all patients serological and clinical signs of the autoimmune disease recurred early or persisted. These observations should be regarded as a cautionary note concerning the efficacy of high-dose therapy followed by transplantation of unmanipulated autologous stem cells for treatment of severe autoimmune diseases.  相似文献   
83.
Cryptococcus neoformans is the most common cause of life threatening meningoencephalitis in HIV-infected patients. Diagnosis is based on tests for cryptoccocal antigen in serum and cerebrospinal fluid, and on culture of the organism. We present a case of AIDS-related cryptococcal meningoencephalitis unresponsive to antifungal combination therapy, despite of evidence of fungal susceptibility in vitro. Significant decreases in cryptococcal antigen titers in serum and cerebrospinal fluid did not correlate with progress in disease and fatal outcome.  相似文献   
84.
The stable transfection of the canine CD34(-) multipotent cell line DO64 with retroviral constructs containing the cDNA for the canine major histocompatibility complex (MHC) class II DR genes led to the cell clone DO64#14, which is characterized by malignant transformation and tumor growth in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. The additional expression of p27(kip-1) in the transformed cell clone partially reversed the malignant phenotype. Because several proteins associated with lipid rafts are involved in signal transduction and because changes of lipid raft composition are linked to the pathogenesis of leukemias, raft-associated proteins in DO64 cells and the deduced transformed cell clones were compared using a proteomic approach. Raft-associated proteins were separated by two-dimensional electrophoresis and identified by MALDI-TOF-MS. Here we show that the stem cell line DO64 and the deduced cell clones can clearly be distinguished by differences in the expression of a number of raft-associated proteins, namely caveolin-1, flotillin- 1, vimentin, galectin-3, and glyceraldehyde-3-phosphate dehydrogenase. All identified proteins play an important role in cellular functions and may therefore participate in raft-mediated leukemic transformation. Therefore, our study suggests that the analysis of lipid raft protein composition may be useful for the identification of molecular markers of the transformation process.  相似文献   
85.

Background  

Pelvic organ prolapse is a common health problem, affecting up to 40% of parous women over 50 years old, with significant negative influence on quality of life. Vaginal hysterectomy is currently the leading treatment method for patients with symptomatic uterine prolapse. Several studies have shown that sacrospinous fixation in case of uterine prolapse is a safe and effective alternative to vaginal hysterectomy. However, no large randomized trials with long-term follow-up have been performed to compare efficacy and quality of life between both techniques.  相似文献   
86.
进展期胃癌淋巴结转移与临床病理特征的关系   总被引:3,自引:1,他引:3  
目的:探讨进展期胃癌淋巴结转移与临床病理特征的关系,为临床上进行合理的淋巴结清扫提供依据。方法:对55例进展期胃癌资料进行回顾性分析,术后常规解剖原发灶及各组淋巴结,并标记和计数,分析肿瘤部位、肿瘤大小、浸润深度、分化程度及Lauren分型与淋巴结转移率的关系。结果:进展期胃癌淋巴结转移率为74.5%;U、M、L区及全胃癌淋巴结转移率为85.7%、87.5%、67.6%和83.3%,各区和全胃癌淋巴结转移率差异无统计学意义(P〉0.05);浆膜受侵的胃癌淋巴结转移率为82.5%,明显高于浆膜未受侵者(53.3%)(P〈0.05);弥漫型胃癌淋巴结转移率为83.3%,明显高于肠型(64.0%)(P〈0.05);直径〉5cm癌灶淋巴结转移率为90.0%,明显高于直径≤5cm的胃癌患者(65.7%)(P〈0.05);浸润深度、Lauren分型和肿瘤大小是影响淋巴结转移率的主要因素,其中浸润深度为独立影响因素。结论:术中淋巴结清扫范围应结合肿瘤部位、肿瘤大小、浸润深度、分化程度及Lauren分型做出判断,并考虑患者的全身情况,合理选择淋巴结清扫范围。  相似文献   
87.
OBJECTIVE: This study was designed to investigate the possible synergism of atenolol and nitrendipine on blood pressure (BP) and blood pressure variability (BPV) reductions, baroreflex sensitivity (BRS) amelioration, and organ protection in hypertensive rats. METHOD: The dose was 20 mg/kg for atenolol, 10 mg/kg for nitrendipine and 20 + 10 mg/kg for the combination of these two drugs. In an acute study, a single dose was given via a catheter previously inserted into the stomach in spontaneously hypertensive rats (SHR).  相似文献   
88.
建立测定复方红甲凝胶中乳糖酸红霉素的含量测定方法。方法:以一阶导数光谱的谷一零位值法测定乳糖酸红霉素的含量,测定波长λ谷=490±lnm。结果:回收率100.6%,RSD为3.1%,线性范围40~120μg/ml。结论:方法简便,结果准确,重现性好,适合于该制剂的含量测定。  相似文献   
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