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41.
Urosepsis is defined as sepsis caused by a urogenital tract infection. Urosepsis in adults comprises approximately 25% of all sepsis cases, and is in most cases due to complicated urinary tract infections. The urinary tract is the infection site of severe sepsis or septic shock in approximately 10–30% of cases. Severe sepsis and septic shock is a critical situation, with a reported mortality rate nowadays still ranging from 30% to 40%. Urosepsis is mainly a result of obstructed uropathy of the upper urinary tract, with ureterolithiasis being the most common cause. The complex pathogenesis of sepsis is initiated when pathogen or damage‐associated molecular patterns recognized by pattern recognition receptors of the host innate immune system generate pro‐inflammatory cytokines. A transition from the innate to the adaptive immune system follows until a TH2 anti‐inflammatory response takes over, leading to immunosuppression. Treatment of urosepsis comprises four major aspects: (i) early diagnosis; (ii) early goal‐directed therapy including optimal pharmacodynamic exposure to antimicrobials both in the plasma and in the urinary tract; (iii) identification and control of the complicating factor in the urinary tract; and (iv) specific sepsis therapy. Early adequate tissue oxygenation, adequate initial antibiotic therapy, and rapid identification and control of the septic focus in the urinary tract are critical steps in the successful management of a patient with urosepsis, which includes early imaging, and an optimal interdisciplinary approach encompassing emergency unit, urological and intensive‐care medicine specialists.  相似文献   
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Background  The goal of this study was to test whether myocardial triglyceride (TG) turnover including oxidation of TG-derived fatty acids (FA) could be assessed with PET and 11C-palmitate. Methods and Results  A total of 26 dogs were studied fasted (FAST), during Intralipid infusion (IL), during a hyperinsulinemic-euglycemic clamp without (HIEG), or with Intralipid infusion (HIEG + IL). 11C-palmitate was injected, and 45 minutes were allowed for labeling of myocardial TG pool. 3D PET data were then acquired for 60 minutes, with first 15 minutes at baseline followed by 45 minutes during cardiac work stimulated with constant infusion of either phenylephrine (FAST, n = 6; IL, n = 6; HIEG + IL, n = 6) or dobutamine (FAST, n = 4; HIEG, n = 4). Myocardial 11C washout during adrenergic stimulation (AS) was fitted to a mono-exponential function (Km(PET)). To determine the source of this 11C clearance, Km(PET) was compared to direct coronary sinus-arterial measurements of total 11C activity, 11C-palmitate, and 11CO2. Before AS, PET curves in all groups were flat indicating absence of net clearance of 11C activity from heart. In both FAST groups, AS resulted in negligible net 11C activity and 11CO2 production higher than net 11C-palmitate uptake. AS with phenylephrine resulted in net myocardial uptake of total 11C activity and 11C-palmitate in IL and HIEG + IL, and 11CO2 production lower than 11C-palmitate uptake. In contrast, AS with dobutamine in HIEG resulted in net clearance of all 11C metabolites (total 11C activity, 11C-palmitate and 11CO2) with 11CO2 contributing 66% to endogenous FA oxidation. The AS resulted in significant Km(PET) in all the groups, except HIEG + IL. However, positive correlation between Km(PET) and 11CO2 was observed only in HIEG (R 2 = 0.83, P = .09). Conclusions  This is the first study to demonstrate that using PET and pre-labeling of intracardiac TG pool with 11C-palmitate, noninvasive assessment of myocardial TG use is feasible under metabolic conditions that favor endogenous TG use such as increased metabolic demand (β-adrenergic stimulation of cardiac work) with limited availability of exogenous substrate (HIEG).  相似文献   
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Does altered biomechanics cause marrow edema?   总被引:21,自引:0,他引:21  
Schweitzer  ME; White  LM 《Radiology》1996,198(3):851
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In this study, on the basis of the inhibiting action of l-dopa administration on prolactin (PRL) secretion, we evaluated in a number of short children the levels of PRL during the provocative stimuli test with l-dopa in order to identify an index able to give reliability to the test and to investigate whether some differences may exist among the subjects showing a different response in growth hormone (GH) secretion to l-dopa. We examined 76 subjects (44 boys and 32 girls) with chronological age from 4.5-15.17 years. The subjects, on the basis of the GH peaks during two provocative stimuli tests [l-dopa and insulin-induced hypoglycemia (IIH)], were subdivided into 3 groups: group 1 (n = 24) with both deficient responses (peak less than 10 ng/ml); group 2 (n = 28) with discordant responses and further subdivided into group 2a (n = 14) with normal responses to IIH and 2b (n = 14) with a normal response to l-dopa; group 3 (n = 24) with both normal responses. PRL levels peaked between times -20' (58 cases) and +20' (2 cases) whereas nadir occurred between +80' (4 cases) and +120 (48 cases) without any significant difference (p = ns) among the groups. PRL levels significantly decreased in all groups, also in those with a deficient response to l-dopa (1 and 2a); furthermore no significant correlation between PRL and GH levels was demonstrated. In conclusion, this study showed the importance of PRL evaluation during l-dopa test in order to give reliability to the test and did not demonstrate any difference in PRL levels among the examined groups of short children.  相似文献   
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It has been suggested that proliferation of enterobacteriaceae and/or anaerobes in the duodenum of some children with acute diarrhoea determines whether the episode becomes persistent. A review of published studies and the comparison of cultures of duodenal aspirates from Peruvian children with acute and persistent diarrhoea and diarrhoea-free children did not support this hypothesis. Although many children had enterobacteriaceae and/or anaerobes cultured there was no correlation with clinical and nutritional outcome. Age, nutritional status, the environment and the aetiology of the episode were determinants of the duodenal microflora independent of diarrhoea. Culture of the duodenal aspirates did not increase the yield of enteropathogens which were isolated more frequently from stools than from the duodenum. Despite the presence of a single strain or serotype of enterobacteriaceae suggesting that these bacteria were colonizing the duodenum, we were unable to demonstrate any adherence mechanisms in the majority of them. Two often bacteria with no other evidence of virulence caused diarrhoea in the RITARD rabbit model.  相似文献   
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