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51.
BACKGROUND: Recent guidelines for those with acute low back pain have advocated early resumption of normal activity and increased physical activity. Little is known about the relationship between low back pain and physical activity, and on the impact of that relationship on the promotion of increased levels of physical activity within a general practice population. OBJECTIVES: We aimed to explore associations between factors that influence changes in physical activity and the way individuals perceive and behave with their low back pain, and the impact of those perceptions and behaviour on physical activity. METHODS: Twenty-seven informants were chosen using a purposive sample from a larger group of individuals who, because of their low back trouble, had been referred by their GPs to a community-based, single-blind, randomized controlled trial (RCT) at the University of York, which is evaluating the effectiveness and cost-effectiveness of a progressive exercise programme. Fifty-four interviews were conducted with this subgroup of the RCT; four informants were interviewed once, 19 twice and four of them three times. Interviews were transcribed and analysed using manual and computer-aided approaches. RESULTS: Physical activity was perceived as (i) activities of daily living, (ii) activities causing breathlessness that they went out of the way to do and (iii) more competitive-type activity. The avoidance of physical activity and fear of pain returning were the two main factors directly associated with informants' backs and changes in physical activity. These two factors hindered increases in physical activity, even though the majority of informants believed strongly that being physically active helped ease their low back pain. CONCLUSIONS: When advocating that individuals with acute low back pain return to or increase physical activity, it is important that clinicians identify avoidance of physical activity and/or fear of pain at the earliest stage in order to tailor advice and reassurance appropriately. If avoidance of activity and fear of pain is identified and clinicians want to encourage patients to take up and sustain increased physical activity, they should explore issues of fear of pain, and avoidance of and confidence to do physical activities, in addition to other factors influencing physical activity.  相似文献   
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The acute morphological response to amosite asbestos in the guinea pig was studied by light microscopy and by transmission, scanning, and scanning transmission electron microscopy. Fiber identification was carried out by energy dispersive X-ray analysis. Animals were studied at postinjection intervals of 2, 4, and 12 hr and 1-7 days. Three groups of test animals were studied for each time interval. These consisted of a vascularly perfused parenchymal group and a free cell lavaged group. The information obtained was compared with saline-injected and normal control animals. The acute tissue response was characterized by intraalveolar, not interstitial, events. The early phagocytic response was shared between polymorphs and macrophages, while in the longer intervals, the macrophages were the phagocytic cell type. Packaging differences within the two types of phagocytes were seen. Endothelial stability was noted, while some edematous type I pneumocytes were observed. Fibrotic involvement was limited to some intraalveolar fibrin deposits. It is suggested that the term "free asbestos fibers" refers to an extracellular event, while intracellular fibers are coated with either a membranous sheath, a siderosome, or a classical ferruginous coating.  相似文献   
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Patients undergoing human menopausal gonadotropin (hMG) superovulation were reviewed retrospectively to determine whether fecundity was greater for intrauterine insemination (IUI) than timed intercourse. Forty patients with unexplained infertility, American Fertility Society I or II endometriosis, luteal phase defect and/or cervical factor were treated with hMG alone or hMG plus IUI. Twenty-eight underwent 52 cycles of hMG/IUI, and 19 underwent 31 cycles of hMG. The probability of pregnancy after four cycles was significantly better in the hMG/IUI group (.90) than the hMG group (.37, P = .049). There was a 54.5% multiple pregnancy rate, and one patient was admitted to the hospital for hyperstimulation. When traditional therapy fails, hMG/IUI significantly increases the pregnancy rates as compared to hMG with timed intercourse in a "good prognosis" group of patients.  相似文献   
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Quantitative fluorescence image analysis incorporates the 2 diagnostic techniques of cytological analysis with quantitation of deoxyribonucleic acid (DNA). Exfoliated urinary cells are ideal for analysis by this method, which allows the identification of "rare event" abnormal cells. We evaluated the urine from 50 children who had undergone cystoscopy or were catheterized for other reasons. The urine was free of infection by urinalysis. Cytological analysis demonstrated normal or atypical cells in all patients. Of the patients 1 (2%) had greater than 2 of 500 cells analyzed with greater than 5C DNA and 4 (8%) had greater than 2 of 500 cells with greater than 5C double stranded nucleic acid. These data suggest that it may be "normal" for urine to contain "rare event" abnormal cells. The significance of this finding is unclear at present.  相似文献   
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Orbital drainage from cerebral arteriovenous malformations   总被引:3,自引:0,他引:3  
OBJECTIVE: To describe the neuro-ophthalmic findings in patients with orbital drainage from cerebral arteriovenous malformations (AVMs). METHODS: We reviewed the records of 100 consecutive adult patients with cerebral AVMs who presented to our institution during a 4-year period. All patients with orbital drainage were identified, and their neuro-ophthalmic evaluations were reviewed. RESULTS: Three patients (3%) were identified with orbital drainage from a cerebral AVM. The first patient presented with typical chiasmal syndrome (reduced visual acuity, bitemporal hemianopia, and optic atrophy). Magnetic resonance imaging demonstrated a large left temporal and parietal lobe AVM with compression of the chiasm between a large pituitary gland and a markedly enlarged carotid artery. The second patient presented with headaches and postural monocular transient visual obscurations. Examination revealed normal visual function with minimal orbital congestion and asymmetrical disc edema, which was worse in the left eye. Magnetic resonance imaging revealed a large right parietal and occipital lobe AVM without mass effect or hemorrhage and an enlarged left superior ophthalmic vein. The third patient had no visual symptoms and a normal neuro-ophthalmic examination; a right parietal lobe AVM was discovered during an examination for the cause of headaches. CONCLUSION: Orbital drainage from cerebral AVMs is rare. Manifestations may include anterior visual pathway compression, dilated conjunctival veins, orbital congestion, and asymmetrical disc swelling.  相似文献   
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Formal retrospective case review and sudden infant death   总被引:2,自引:0,他引:2  
A review of 24 consecutive sudden infant deaths was undertaken to evaluate the importance of the various stages in the postmortem assessment of such cases. Death in three cases was caused by obvious trauma. Of the remainder, 16 were attributed to sudden infant death syndrome (SIDS), 4 to accidental asphyxia (identified by death scene examination and/or formal case review) and 1 to a lingual thyroglossal duct cyst. Three (14%) of 21 deaths thought to be SIDS after postmortem examination were attributed to asphyxia following subsequent formal case review.  相似文献   
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