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971.
The 6-min walking distance (6MWD) test is used in clinical practice and research into patients with chronic obstructive pulmonary disease (COPD). However, little is known about natural long-term change in this parameter. The 6MWD was measured at baseline and then annually for 5 yrs in 294 patients with COPD and its annual rate of decline was determined. Forced expiratory volume in one second (FEV1) was also measured and the relationship between changes in both markers was explored. At baseline, the median 6MWD was 380 m (range 160-600 m). It declined by 19% (16 m.yr(-1)) over the 5 yrs compared with baseline in patients with American Thoracic Society/European Respiratory Society stage III COPD (FEV1 30-50% predicted) and by 26% (15 m.yr(-1)) in patients with stage IV COPD (FEV1 <30% pred). Over the 5-yr follow-up, the proportion of patients with a minimal clinically significant decline of 54 m increased with the severity of the disease. It was 24% in stage II, 45% in stage III, and 63% in stage IV disease. In contrast, the rate of decline of FEV1 was greater in patients with milder airflow obstruction and lesser in patients with lower absolute FEV1 values. In conclusion, the 6-min walking distance test provides increasingly useful information as the severity of chronic obstructive pulmonary disease increases.  相似文献   
972.
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974.
A retrospective and comparative study of women delivered by caesarean section over two different 3-year periods was conducted at Olabisi Onabanjo University Teaching Hospital, Sagamu, Nigeria. The caesarean section rate (CSR) increased from 10.3% in 1989-1991 to 23.1% in 2000-2003. The most frequent indication in both periods was different: prolonged/obstructed labour (20.0%) in 1989-1991 and antepartum haemorrhage (14.9%) in 2000-2003. Malpresentation, antepartum haemorrhage and pre-eclampsia/eclampsia were responsible for 51.7% of the difference in the CSR recorded between both periods. The CSR rose from 13.3% to 25.0% while the instrumental vaginal delivery (IVD) rate decreased significantly by 11.4% among the nulliparous women between the periods. Increase in CSR can be attributed mainly to reduction in IVD rate and alteration in the management of labour complications and induction policy. Strategies to reduce the CSR should cut across all indications and focus on encouraging instrumental vaginal deliveries, especially among nulliparous women.  相似文献   
975.
OBJECTIVE: In light of recent terrorist events and the potential threat of smallpox as a biological agent, we present information concerning smallpox to better inform the otolaryngologist concerning this disease and its prevention. STUDY DESIGN: We performed a review of the smallpox and smallpox vaccination literature over the past 200 years using MEDLINE, PREMEDLINE, Centers for Disease Control and Prevention Internet site, World Health Organization Internet site, and references found in previous publications not found in MEDLINE or PREMEDLINE. Our search focused on the pathogenesis, clinical presentation, course, unique manifestations in the head and neck, diagnosis, and treatment of smallpox, as well as the method of smallpox vaccination, vaccination contraindications, and complications. RESULTS: Smallpox is a viral disease with a high mortality rate. Its clinical course, manifestations, and methods of prevention are carefully analyzed in light of otolaryngology practice. CONCLUSION: Smallpox manifestations in the head and neck often presented as acute airway obstruction and also as long-term sequelae such as ectropion, nasal vestibular stenosis, conductive hearing loss, and blindness. Most chronic sequelae involve the head and neck. Smallpox vaccination is effective but not without potential serious risks.  相似文献   
976.
The effects of OSM on proliferation and differentiation of osteosarcoma and nontransformed osteoblasts were analyzed. OSM downregulates osteoblast markers but induces the glial fibrillary acidic protein by the combined activation of PKCdelta and STAT3, offering new lines of therapeutic investigations. INTRODUCTION: Oncostatin M (OSM) is a multifunctional cytokine of the interleukin-6 family implicated in embryonic development, differentiation, inflammation, and regeneration of various tissues, mainly the liver, bone, and the central nervous and hematopoietic systems. One particularity of OSM relies on its growth inhibitory and pro-differentiating effects on a variety of tumor cell lines such as melanoma, providing arguments for a therapeutic application of OSM. The objective of this study was to analyze the effects of OSM on osteosarcoma cell lines proliferation and differentiation. MATERIALS AND METHODS: Proliferation was analyzed by 3H thymidine incorporation. Differentiation was analyzed by semiquantitative RT-PCR and immunocytochemistry for various markers. Alizarin red S staining was used to evaluate bone nodule formation. Morphological changes were studied by confocal and electron microscopy. Western blotting, kinases inhibitors, and dominant negative STAT3 were used to identified the signaling pathways implicated. RESULTS: OSM inhibits the growth of rat osteosarcoma cell lines as well as normal osteoblasts, in correlation with induction of the cyclin-dependent kinases inhibitor p21WAF1. However, OSM reduces osteoblast markers such as alkaline phosphatase, osteocalcin, and bone sialoprotein, leading to strong inhibition of mineralized nodule formation. This inhibitory effect is restricted to mature osteoblasts and differentiated osteosarcoma because OSM effectively stimulates osteoblast markers and bone nodule formation in early, but not late, bone marrow mesenchymal stem cell (BMSC) cultures. In osteosarcoma cells or BMSC, OSM induces expression of the glial fibrillary acidic protein (GFAP) as well as morphological and ultrastructural changes, for example, elongated shape and bundles of microfilaments in cell processes. Rottlerin (PKCdelta inhibitor), and to a lesser degree UO126 (MEK/ERK inhibitor), prevents the loss of osteoblastic markers by OSM, whereas dominant negative STAT3 prevents GFAP induction. CONCLUSIONS: These results highlight the particular gene expression profile of OSM-treated osteosarcoma cells and BMSCs, suggesting either a osteocytic or a glial-like phenotype. Together with the implication of PKCdelta, ERK1/2, and STAT3, these results offer new lines of investigations for neural cell transplantation and osteosarcoma therapy.  相似文献   
977.
978.
After a comprehensive rernew of the literature on syphilitic aortitis, Longcope, (1) stated in 1913; ": . . . the presence of spiro: chetes in these lesions, as might be expected, cannot by any means be constantly demonstrated with Levaaiti stain. . . . . . . That these organisms are ''Treponema pallidum seems almost certain thouS:h actual proof of such by culture from the arterial lesions, a most difficult task, or direct inoculation into animals, has not as yet been accomplished."  相似文献   
979.
980.
Free flaps have been used for over 30 years. During this period, improved anatomical understanding has increased donor options and available pedicle lengths, permitting safer, single-stage reconstructions with simpler anastomoses. Refinements, such as perforator flaps in particular, have greatly improved donor morbidity, recipient site cosmesis, and the ability to replace 'like with like' while retaining options for innervation. This case highlights the evolution from one of Europe's first free tissue transfers, effectively a perforator flap, through the advent of free muscle flaps to the current generation of contourable perforator flaps. Free flap transfer has become increasingly sophisticated, safer, and more predictable, yet the potential quality of reconstructive outcome has changed little.  相似文献   
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