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21.
Tissue macrophages, which participate in chronic synovial inflammation, differentiate from haemopoietic precursors in bone marrow and subsequently in tissue. During this process, they acquire attributes which are essential for their function in inflammation. Modulation of this process may represent a means of regulating inflammatory competence of macrophages in inflammatory joint disease. The action of aurothiomalate (ATM), an anti-rheumatic gold compound, on the differentiation of a promonocytic cell line (U937) was, therefore, examined inin vitro systems. U937 cells exposed to retinoic acid (RA) for 4 days or to phorbol myristate acetate (PMA) for 2 days acquired characteristics of macrophages, including the capacity to produce superoxide (O 2 ), responsiveness to formyl-methionyl-leucyl-phenylalanine (fMLP) and reduced proliferation. The activity of transglutaminase also increased in RA-exposed cultures. The effect of ATM exposure on acquisition of these characteristics was small and differed between RA- and PMA-stimulated cells.  相似文献   
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In order to achieve a clinical pregnancy rate higher than that achieved following initial adoption of in-vitro fertilization embryo transfers, more than one embryo is transferred. This has led to a substantial increase in unwanted multiple pregnancy rates with IVF as compared with natural conception. What is therefore required is a simple, clinically useful embryo scoring system, to reflect embryo developmental potential, which will enable the selection of the optimal number of embryos to transfer in order to achieve the maximum pregnancy rate with a low incidence of high order multiple pregnancies. We believe that the Cumulative Embryo Score (CES) achieves these aims. On the day of embryo transfer the grade of each embryo transferred was multiplied by the number of blastomeres to produce a score for each embryo, and summation of the scores obtained for all the embryos transferred gave the CES. The grouped pregnancy rates obtained rose as the CES increased to maximum of 42. A continued increase in the CES above 42 did not result in any further rise in the pregnancy rate. However, an analysis of all our IVF pregnancies showed that the multiple pregnancy rate continued to rise above a CES of 42. By restricting the CES per embryo transfer to 42, 78% of triplet pregnancies and 100% of the quadruplet IVF pregnancies could have been predicted and potentially avoided.  相似文献   
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We report a case in which thrombelastography (TEG) and Sonoclot analysis were used for diagnosis and treatment decisions in a patient with abruptio placentae and disseminated intravascular coagulation. In addition to providing enough information for evaluation and treatment of this patient, the TEG and Sonoclot results were obtained more quickly, with smaller blood samples and with less expense to the patient in comparison to the standard coagulation tests in our institution. Although the TEG and Sonoclot results were assessed independently of the other test and each provided similar information in this case, the TEG may be the preferred tool in evaluating coagulopathies, based on computerization and strong literature support.  相似文献   
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To ascertain how effective the Beck Depression Inventory for Primary Care (BDI-PC) was in screening for DSM-IV major depression disorders (MDD) in outpatients who were scheduled for routine office visits with physicians specializing in internal medicine, the BDI-PC was administered to 60 male and 60 female outpatients. The internal consistency of the BDI-PC was high (alpha 0.85), and the Mood Module from the Primary Care Evaluation of Mental Disorders was used to diagnose MDD. The BDI-PC scores were not significantly correlated with sex, age, ethnicity, or total number of medical diagnoses. A BDI-PC cutoff score of 4 and above yielded 98% maximum clinical efficiency with 97% (95% CI 82%-99%) sensitivity and 99% (95% CI 94%-99%) specificity rates, respectively, for identifying patients with and without MDD. The BDI-PC is discussed as an effective case-finding instrument for screening primary care patients for MDD.  相似文献   
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In this study we have analyzed the vascular response induced in the two- stage carcinogenesis model in SENCAR mice. The role of angiogenesis has not been explored in this model, which is the paradigm of multistage carcinogenesis and a model for neoplastic lesions derived from exophytic premalignant lesions (e.g. colon carcinoma, bladder papilloma). We investigated if angiogenesis is involved in the formation of papillomas and in the progression from papilloma to carcinoma. To this end we analyzed the vasculature of normal and hyperplastic skin, focal epidermal hyperplasias that are precursors of papillomas, papillomas at different stages and squamous cell carcinomas. We also analyzed the vascularization of papillomas induced in two strains of mice that differ in their susceptibility to malignant progression. We show here that angiogenesis is turned on in the earliest stages of papilloma formation. In late stages, regardless of state of progression, the predominant response is an increase in the size of blood vessels. Thus, in the SENCAR mouse model, representative of exophytic tumors, the angiogenesis switch is a very early event, probably mechanistically related to the development of the primarily exophytic lesions. Therefore, the density of blood vessels cannot be used as a predictor of malignant progression in this model.   相似文献   
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The major burden of preterm birth is in the developing world, where most of the increasing death and morbidity is secondary to infectious diseases such as malaria, HIV, tuberculosis, bacterial vaginosis and intestinal parasites. In some developing countries, the growth of medical care has outstripped the growth of preventive public health, with an associated increase in iatrogenic preterm births. In developed countries, more than one-third of preterm births are medically indicated because of conditions such as fulminating pre-eclampsia or severe intrauterine growth restriction. Neither of these conditions is currently preventable. One in five preterm births is associated with multiple pregnancy, and these have been greatly increased by assisted reproduction techniques. The use of tocolytics has proved disappointing perhaps because inflammation rather than spontaneous uterine activity is increasingly recognised as the final common pathway. Inappropriate antibiotics used late in pregnancy are ineffective and may have adverse effects. Currently, the most promising interventions are public health related and include reducing the transmission of communicable diseases, improvements in the management of diabetes and reduction in harmful behaviours such as smoking and drug abuse.  相似文献   
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