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排序方式: 共有338条查询结果,搜索用时 15 毫秒
1.
A David A Pelosi E McDonald D Stephens D Ledger R Rathbone A Mann 《BMJ (Clinical research ed.)》1990,301(6762):1199-1202
OBJECTIVES--To determine the prevalence and associations of symptoms of fatigue. DESIGN--Questionnaire survey. SETTING--London general practice. PARTICIPANTS--611 General practice attenders. MAIN OUTCOME MEASURES--Scores on a fatigue questionnaire and reasons given for fatigue. RESULTS--10.2% Of men (17/167) and 10.6% of women (47/444) had substantial fatigue for one month or more. Age, occupation, and marital status exerted minor effects. Subjects attributed fatigue equally to physical and non-physical causes. Physical ill health, including viral infection, was associated with more severe fatigue. Women rather than men blamed family responsibilities for their fatigue. The profile of persistent fatigue did not differ from that of short duration. Only one person met criteria for the chronic fatigue syndrome. CONCLUSIONS--Fatigue is a common complaint among general practice attenders and can be severe. Patients may attribute this to physical, psychological, and social stress. 相似文献
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G Pelosi M Zannoni F Caprioli L Faccincani M G Battistoni G Balercia L Bontempini 《Histology and histopathology》1991,6(4):575-583
We report a case of benign multicystic mesothelial proliferation (the so-called multicystic peritoneal mesothelioma) arising multifocally in the abdomen of a 46-year-old white man. His anamnesis showed an 8-year history of intermittent pain in the right lower abdominal quadrant. Mucin stains, immunohistochemistry, and electron microscopy confirmed the mesothelial origin of the lesion. Review of the available literature allowed us to find another 85 reported cases of benign multicystic mesothelial proliferations of the peritoneum. Out of these cases, eighteen only occurred in men, the majority being reported in middle-aged women mostly with complaints of abdominal pain. Electron microscopy or immunohistochemistry are needed to make a differential diagnosis towards other multicystic lesions, such as peritoneal cystic lymphangioma. Although multicystic mesothelial proliferations of the peritoneum have often been regarded as benign neoplasms, the true nature--neoplastic or hyperplastic--of these lesions still remains greatly elusive. Therefore, we believe that the unbinding term benign multicystic mesothelial proliferation (first used with regard to the unique hitherto reported case arisen in the pleural cavity) should be considered at present more appropriate to indicate even these peritoneal lesions. 相似文献
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Direct sequencing of the mitochondrial displacement loop (D-loop) of shrews
(genus Sorex) for the region between the tRNA(Pro) and the conserved
sequence block-F revealed variable numbers of 79-bp tandem repeats. These
repeats were found in all 19 individuals sequenced, representing three
subspecies and one closely related species of the masked shrew group (Sorex
cinereus cinereus, S. c. miscix, S. c. acadicus, and S. haydeni) and an
outgroup, the pygmy shrew (S. hoyi). Each specimen also possessed an
adjacent 76-bp imperfect copy of the tandem repeats. One individual was
heteroplasmic for length variants consisting of five and seven copies of
the 79-bp tandem repeat. The sequence of the repeats is conducive to the
formation of secondary structure. A termination-associated sequence is
present in each of the repeats and in a unique sequence region 5' to the
tandem array as well. Mean genetic distance between the masked shrew taxa
and the pygmy shrew was calculated separately for the unique sequence
region, one of the tandem repeats, the imperfect repeat, and these three
regions combined. The unique sequence region evolved more rapidly than the
tandem repeats or the imperfect repeat. The small genetic distance between
pairs of tandem repeats within an individual is consistent with a model of
concerted evolution. Repeats are apparently duplicated and lost at a high
rate, which tends to homogenize the tandem array. The rate of D- loop
sequence divergence between the masked and pygmy shrews is estimated to be
15%-20%/Myr, the highest rate observed in D-loops of mammals. Rapid
sequence evolution in shrews may be due either to their high metabolic rate
and short generation time or to the presence of variable numbers of tandem
repeats.
相似文献
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大鼠胼胝体内神经肽Y免疫反应阳性纤维的发育 总被引:1,自引:0,他引:1
本实验用免疫组织化学ABC法研究了大鼠胼胝体内神经肽Y免疫反应阳性(NPY-IR)纤维的生后发育。结果发现,许多NPY-IR纤维在大鼠出生时便存在于胼胝体内。NPY-IR胼胝体纤维的密度在生后1周内继续逐渐增高,在第2周内达到最高峰。之后,NPY-IR胼胝体纤维的密度逐渐下降,至第3周末时接近成年时的水平,即仅有少量NPY-IR纤维存在于胼胝体内。这些结果提示在大鼠早期生后发育过程中许多NPY-IR胼胝体纤维是暂时性的,其作用可能与大脑皮质的机能发育有关。 相似文献
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Andrea Moriondo Paolo Pelosi Alberto Passi Manuela Viola Cristiana Marcozzi Paolo Severgnini Vittoria Ottani Marilisa Quaranta Daniela Negrini 《Journal of applied physiology》2007,103(3):747-756
This research investigated whether stretching of lung tissue due to increased positive alveolar pressure swings during mechanical ventilation (MV) at various tidal volumes (V(T)) might affect the composition and/or structure of the glycosaminoglycan (GAG) components of pulmonary extracellular proteoglycans. Experiments were performed in 30 healthy rats: 1) anesthetized and immediately killed (controls, C-0); 2) anesthetized and spontaneously breathing for 4 h (C-4h); and 3) anesthetized, paralyzed, and mechanically ventilated for 4 h with air at 0-cmH(2)O end-expiratory pressure and V(T) of 8 ml/kg (MV-1), 16 ml/kg (MV-2), 24 ml/kg (MV-3), or 32 ml/kg (MV-4), adjusting respiratory rates at a minute ventilation of 270 ml/min. Compared with C-0 and C-4h, a significant reduction of dynamic and static compliance of the respiratory system and of the lung was observed only in MV-4, while extravascular lung water significantly increased in MV-3 and MV-4, but not in MV-1 and MV-2. However, even in MV-1, MV induced a significant fragmentation of pulmonary GAGs. Extraction of covalently bound GAGs and wash out of loosely bound or fragmented GAGs progressively increased with increasing V(T) and was associated with increased expression of local (matrix metalloproteinase-2) and systemic (matrix metalloproteinase-9) activated metalloproteases. We conclude that 1) MV, even at "physiological" low V(T), severely affects the pulmonary extracellular architecture, exposing the lung parenchyma to development of ventilator-induced lung injury; and 2) respiratory mechanics is not a reliable clinical tool for early detection of lung injury. 相似文献
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