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91.
92.
When excluding haemophilia and von Willebrand disease, coagulation factors deficiencies constitute rare autosomal recessive disorders (<1 in 500,000) of less precisely defined epidemiology. We have reported herein the distribution of these entities in the French Basque Country, a genetic isolate of very old individualization with peculiar biological specificities. The prevalence of these disorders was markedly high, especially, as already shown, factor XI deficiency. This unusual profile needs to be discussed in the view of population genetics. 相似文献
93.
[目的]探讨四物汤及其提取物治疗辐射致血虚证小鼠的作用机制和有效物质基础。[方法]γ射线全身照射小鼠制成血虚证模型,观察四物汤对其外周血和造血祖细胞集落的影响,基因芯片检测有效单体芍药苷的分子作用机制。[结果]四物汤、正丁醇提取物、水溶提取物对血虚证小鼠外周的白细胞的恢复有明显促进作用;四物汤和芍药苷增强血虚证小鼠骨髓造血干祖细胞的集落形成能力;芍药苷可促进骨髓基质细胞分泌造血因子(G-CSF,GM-CSF,PDGF-α)等,抑制造血抑制因子(M-CIP)的分泌。[结论]四物汤补血的物质基础可能是芍药苷,促进骨髓基质细胞分泌G-CSF,GM-CSF,PDGF-α等造血因子可能是四物汤补血的作用机制之一。 相似文献
94.
95.
对贵州碘缺乏病(IDD)轻、重病区,碘盐防治后出生的轻度低智及正常智力儿童和非病区对照组儿童头发中硒(Se)、锌(Zn)、铜(Cu)、铁(Fe)进行测定。结果显示轻病区儿童发Se、Zn、Cu量及重病区儿童发Cu量显著低于非病区对照组。但是在轻、重病区内正常智力与轻度低智儿童头发中Se、Zn、Cu、Fe量分别比较都没有显著差异。提示病区轻度低智儿童的发生与发中Se、Zn、Cu、Fe的变化关系不密切。 相似文献
96.
目的研究经咽旁入路选择性的切除大鼠垂体前叶,以制备大鼠垂体前叶激素缺乏模型如生长激素(GH)缺乏模型。方法经腹侧咽旁入路,运用显微神经外科技术经基蝶骨底选择性地切除垂体前叶。然后采用竞争免疫沉淀法检测大鼠生长激素的含量,术后统计死亡率、成功率。结果切除垂体前叶后大鼠的死亡率为26.7%,成活率为73.3%,全切率为91%;成功制备大鼠模型的GH显著低于假手术组和对照组。结论运用显微外科技术可以成功的选择性的切除大鼠垂体前叶,制备出垂体前叶激素如生长激素缺乏的动物模型。 相似文献
97.
Diagnosis of testosterone deficiency is important to identify patients who might benefit from testosterone replacement therapy. Unfortunately, the diagnosis of hypogonadism may be a challenge for many practicing physicians, including endocrinologists and urologists. Signs and symptoms, such as sexual dysfunction, change in body composition, lethargy, and mood changes, are nonspecific and the available questionnaires are generally not useful in clinical practice. The diagnosis of testosterone deficiency is ultimately based on measurement of serum testosterone levels. However, marked variations in the reference ranges of serum testosterone levels among laboratories pose a challenge for physicians when interpreting the results. In addition, initial laboratory assessments usually determine total testosterone levels. About 1–2% of total testosterone is free and a further 30–50% is bound with low affinity to albumin; only these two components are bioavailable to the target tissues. In general, assuming the normal reference range for serum total testosterone in adult men is 300–1000 ng/dl (10–35 nmol/l), levels of < 250 ng/dl (8.7 nmol/l) suggest the patient is likely to be hypogonadal, whereas levels of > 350 ng/dl (12.7 nmol/l) suggest the symptoms may not be due to androgen deficiency. Values between 250 to 350 ng/dl warrant a repeat morning serum testosterone determination with assessment of free or bioavailable testosterone. In men with symptoms suggestive of androgen deficiency and borderline serum testosterone levels, where there are no contraindications to androgen therapy, a short therapeutic trial of testosterone may be justified. 相似文献
98.
目的 探讨二至天癸颗粒对黄体功能不健所致不孕症患者的治疗作用及机理.方法 将60例黄体功能不健性不孕症患者随机分为二至天癸颗粒组(试验组)30例和六味地黄颗粒组(对照组)30例,观察两组治疗后中医证候改善情况,黄体中期血清雌二醇(E2)、孕酮(P)水平,黄体中期子宫内膜白血病抑制因子(LIF)表达,以及两组患者的妊娠率.结果 治疗后试验组患者中医证候改善程度优于对照组(P<0.05).试验组黄体中期血清P水平及子宫内膜LIF表达量均明显高于对照组(P<0.05);两组血清E2虽较治疗前有所降低,但差异均无统计学意义(P>0.05).试验组妊娠率亦高于对照组(P<0.05).结论 二至天癸颗粒治疗黄体功能不健性不孕症可能与其提高子宫内膜LIF的表达从而影响子宫内膜容受性有关. 相似文献
99.
Bleeding tendency in factor (F)XI deficiency may result from premature clot lysis due to insufficient thrombin activatable fibrinolysis inhibitor (TAFI) activation. Thrombomodulin (TM), upon binding to thrombin, is capable of modulating TAFI activation. In this study, we investigated the effects of plasma TM on fibrinolysis in FXI-deficient patients. A clot lysis assay showed the defective down-regulation of fibrinolysis in FXI-deficient patients as compared with normal controls. To evaluate the effects of plasma TM on fibrinolysis, a monoclonal anti-TM IgG was preincubated with plasma for 30 min. The presence of anti-TM IgG significantly prolonged the clot lysis times both in the FXI-deficient and normal plasma, indicating that plasma TM stimulated fibrinolysis. Furthermore, the presence of anti-TM IgG not only reduced protein C activation, but also increased thrombin generation and TAFI activation. The profibrinolytic effect of plasma TM was inhibited in the assay by including either a monoclonal anti-TAFI IgG or a specific TAFI inhibitor--carboxypeptidase inhibitor (CPI). Our results indicate that the impaired thrombin generation in FXI-deficient patients leads to the defective down-regulation of fibrinolysis, and that plasma TM stimulates fibrinolysis through APC pathway which inhibits TAFI activation. The profibrinolytic effect of plasma TM may contribute to the bleeding tendency observed in some FXI-deficient patients. 相似文献
100.
Beatriz Lara Cristian de la Roza Sara Vil�� Rafael Vidal Marc Miravitlles 《INT J CHRONIC OBSTR》2007,2(3):393-398
The Spanish registry of alpha-1 antitrypsin deficiency was founded in 1993 and became a member of the International Registry (AIR) in 1999. We describe the updating process following its incorporation into AIR and compare the data collected in the first period (1993–1999) and the second period (1999–2005), during which time patients were included exclusively by internet.The registry included 301 patients during period 1, 69% males and 46% had a history of smoking. Their mean age was 46 years (SD = 13) and 284 (94%) had the ZZ phenotype, 49% received augmentation therapy. During period 2, 161 new cases were included, 63% of whom were males with a mean age of 44 years (SD = 16). A total of 126 (78%) had the ZZ phenotype. Only 12% received augmentation therapy. A total of 462 different patients were included in both periods. Significant differences were observed in the number of cases with the SZ phenotype and the severity of FEV1 impairment between the two periods.Implementation of an internet-based collection of data did not result in a lower rate of reporting to the registry. However, data from a significant number of patient included in period 1 could not be actualized in the new data base. 相似文献