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51.
Fiore P Merli M Andreoli A De Lorenzo A Masini A Ciuffa L Valeriano V Balotta MT Riggio O 《Clinical nutrition (Edinburgh, Scotland)》1999,18(6):349-351
BACKGROUND AND AIMS: Skinfold anthropometry has been used to evaluate the nutritional status in cirrhosis. Such estimates are based on the calculations which derive from healthy subjects and may not apply to cirrhotic patients. We aimed to calculate the limits of agreement between Skinfold anthropometry (SA) and dual-energy X-ray absorptiometry (DXA) in estimating body fat in cirrhotics. METHODS: Forty cirrhotic patients were studied by both methods. The limits of agreement were estimated by the Bland and Altman method. RESULTS: Percentage body fat was similar when measured by DXA and SA (29.6 +/- 9.2 vs 28.9 +/- 7.5 %). Body fat mass was also similar (20.3 +/- 8.4 vs 20.3 +/- 7.7 kg). The limits of agreement between DXA and SA measurements were -7.04 (95%CI: -9.55 to -5.2) +8.56 (95%CI: +10.7 to +6.4.) in the assessment of percentage body fat and -5.32 (95%CI: -6.77 to -3.87) +5.24 (95%CI: +3.79 to +6.69) in the assessment of fat mass. CONCLUSION: Percentage body fat can be evaluated by SA or DXA with a difference of less then 5% in the majority of cirrhotic patients without overt fluid retention. This result is important when considering the large applicability of SA. 相似文献
52.
S Wang M Liu N E Lewin P S Lorenzo D Bhattacharrya L Qiao A P Kozikowski P M Blumberg 《Journal of medicinal chemistry》1999,42(18):3436-3446
Protein kinase C (PKC) comprises a family of ubiquitous enzymes transducing signals by the lipophilic second messenger sn-1, 2-diacylglycerol (DAG). Teleocidin and its structurally simpler congener indolactam-V (ILV) bind to PKC with high affinity. In this paper, we report our computational docking studies on ILV binding to PKC using an automatic docking computer program, MCDOCK. In addition, we used site-directed mutagenesis to assess the quantitative contribution of crucial residues around the binding site of PKC to the binding affinity of ILV to PKC. On the basis of the docking studies, ILV binds to PKC in its cis-twist conformation and forms a number of optimal hydrogen bond interactions. In addition, the hydrophobic groups in ILV form "specific" hydrophobic interactions with side chains of a number of conserved hydrophobic residues in PKC. The predicted binding mode for ILV is entirely consistent with known structure-activity relationships and with our mutational analysis. Our mutational analysis establishes the quantitative contributions of a number of conserved residues to the binding of PKC to ILV. Taken together, our computational docking simulations and analysis by site-directed mutagenesis provide a clear understanding of the interaction between ILV and PKC and the structural basis for design of novel, high-affinity, and isozyme-selective PKC ligands. 相似文献
53.
INTRODUCTION: Limited information exists concerning physician staffing at mass gathering events. METHODS: A retrospective review of the preparation, planning, and provision of medical care for the United States Air Show was performed. Patient encounters from the air show for the years 1981-1991 also were evaluated. RESULTS: The frequency rate of overall encounters was 8.45 patients/10,000 spectators and hospital transport rate was 0.6/10,000 spectators. The majority of complaints were related to heat or minor injuries. During this period, emergency physicians played a vital role in both medical planning and on-site staffing. Emergency medicine residents also participated. A small patient population received direct benefit from on-site physician intervention. CONCLUSION: The on-site emergency physician is of benefit in event preplanning and reducing the burden on the EMS system during mass gathering events. 相似文献
54.
55.
T.E. Lehmann G. Kroon H.J. Dyson M.A. Lorenzo H. Bermúdez H. Perez 《Chemical biology & drug design》2003,61(5):252-262
Abstract: Spectroscopic techniques have been used to study the conformations of several synthetic peptides with sequences corresponding to the repeat regions of the circumsporozoite proteins of Plasmodium vivax, variants vk‐210 and vk‐247. As has previously been shown for P. falciparum, turn‐like folded conformations are observed, in rapid dynamic equilibrium with extended‐chain forms. These results are consistent with the known similarity of the structural, biosynthetic and immunological properties of the circumsporozoite proteins of different plasmodial species. Additionally, the observation of folded conformers provides a rationale for the effectiveness of these peptides as immunogens and potential vaccines. 相似文献
56.
Primary melanoma of the urinary bladder is a rare neoplasm to which very strict diagnostic criteria apply. Although reports of previous cases exist, these criteria have yet to be met. We report a case of a young lady from whom a malignant melanoma of the bladder was resected. This was presumed to be primary as detailed investigation failed to find any other site from which metastases could have originated. We discuss the diagnostic criteria of this entity and stress the difficulty in conclusively demonstrating that, despite some of these criteria being met, a lesion such as this is primary in origin. This case could be the longest surviving patient with primary melanoma of the bladder, however we will never be able to prove that spontaneous regression of an undiagnosed extravesical primary malignant melanoma did not occur. 相似文献
57.
Increased circulating growth hormone (GH) levels and aberrant response to different stimuli characterize both type 1 diabetes mellitus and chronic uremia and are associated with severe retinal, kidney and heart complications. Combined kidney and pancreas transplantation is a therapy that restores the endogenous, closed-loop, insulin secretion in diabetes and cure uremia. To evaluate if combined transplantation can restore a normal secretion and response of GH to growth hormone releasing hormone (GH-RH), we studied four groups of subjects: (1) seven type 1 diabetic patients with end-stage renal failure who had received pancreas and kidney transplantation (KPTx); (2) six diabetic uremic subjects, candidates for combined transplantation (IDDUP); (3) nine patients with chronic uveitis on immunosuppressive therapy comparable to pancreas recipients, six of whom treated only with prednisone (UVEST), while three (4) were treated with both prednisone and cyclosporin (UVESTCY). All subjects underwent a GH-RH test (50 microg intravenously, i.v., at 13:00 h). Serum insulin levels were significantly higher in IDDUP compared to UVEST (P=0.05) both at baseline and post GH-RH stimulus, while were similar to KPTx (P=0.2) and UVESTCY (P=0.7). In contrast, plasma free fatty acids were similar in all groups. In IDDUP baseline plasma glycerol was higher than in KPTx (P=0.04) and UVEST (P=0.02) and similar to UVESTCY (P=0.36); glycerol concentration did not change after GH-RH (P=0.08). Before and after GH-RH, serum GH levels tended to be higher in IDDUP (P=0.5) and KPTx (P=0.2) compared to UVEST and UVESTCY. Our results indicate that: 1) kidney-pancreas transplantation does not normalize the GH response to GH-RH; 2) GH abnormalities are not due either to the chronic immunosuppressive therapy or to the insulin effect on GH release; 3) GH abnormalities are probably secondary to functional and/or organic complications of the hypothalamus and/or pituitary as a sequela of diabetes mellitus. 相似文献
58.
Lorenzo Alonso Carrión Francisco Jesús González Sánchez Emilio Alba Conejo Esperanza Torres Sánchez 《Clinical & translational oncology》2004,6(8):462-467
Advanced stage ovarian cancer has a high rate of recurrence even after surgery followed by chemotherapy combining carboplatin
and a taxane. New strategies are currently under way to combat this situation and one of the most promising ones is based
on the knowledge that angiogenesis, the mechanism of formation of new blood vessels coupled with the degradation of the extracellular
matrix for metalloproteinases, could be crucial in the development of this tumor. The principal molecule implicated in angiogenesis
process of ovarian cancer is the vascular endothelial growth factor (VEGF). Several studies are now in progress to clarify
its role as a diagnostic tool or its therapeutic implication. Presently, there is no indication for the use of VEGF in a preliminary
diagnosis seeing that an increase in levels can be seen in both benign and malignant ovarian conditions. VEGF is also responsible
for an increase in vascular permeability and is directly related to symptoms such as ascites and pleural effusion, both of
which are frequent in ovarian cancer. Several papers have analised the role of VEGF as a prognostic factor and some of them
do confirm VEGF as an independent prognostic factor in ovarian cancer. VEGF and the metalloproteinase system coupled with
angiogenesis are currently being evaluated as therapeutic targets but no positive results have yet to be seen in this field.
相似文献
59.
G. M. Magnano Mauro Occhi Mauro Di Stadio Paolo Toma' Lorenzo E. Derchi 《Pediatric radiology》1998,28(6):476-477
We report the case of a young girl with recurrent sharp pain in the outer aspect of the ankle. She had no previous trauma.
High-resolution US (HRUS) showed a complete intermittent dislocation of the peroneal tendons. Post-traumatic chronic peroneal
instability is quite common, whereas complete dislocation is rare. HRUS is an important adjunct to clinical examination and
radiographic evaluation of patients with musculoskeletal disorders of the foot and ankle [1]. This paper reports its value
in non-traumatic recurrent dislocation of the peroneal tendons.
Received: 23 May 1997 Accepted: 1 December 1997 相似文献
60.
Prevalence of potentially severe drug-drug interactions in ambulatory patients with dyslipidaemia receiving HMG-CoA reductase inhibitor therapy. 总被引:2,自引:0,他引:2
Alexandra E R?tz Bravo Lydia Tchambaz Anita Kr?henbühl-Melcher Lorenzo Hess Raymond G Schlienger Stephan Kr?henbühl 《Drug safety》2005,28(3):263-275
BACKGROUND: Drug-drug interactions (DDIs) are a well known risk factor for adverse drug reactions. HMG-CoA reductase inhibitors ('statins') are a cornerstone in the treatment of dyslipidaemia and patients with dyslipidaemia are concomitantly treated with a variety of additional drugs. Since DDIs are associated with adverse reactions, we performed a cross-sectional study to assess the prevalence of potentially critical drug-drug and drug-statin interactions in an outpatient adult population with dyslipidaemia. METHODS: Data from patients with dyslipidaemia treated with a statin were collected from 242 practitioners from different parts of Switzerland. The medication list was screened for potentially harmful DDIs with statins or other drugs using an interactive electronic drug interaction program. RESULTS: We included 2742 ambulatory statin-treated patients (mean age +/- SD 65.1 +/- 11.1 years; 61.6% males) with (mean +/- SD) 3.2 +/- 1.6 diagnoses and 4.9 +/- 2.4 drugs prescribed. Of those, 190 patients (6.9%) had a total of 198 potentially harmful drug-statin interactions. Interacting drugs were fibrates or nicotinic acid (9.5% of patients with drug-statin interactions), cytochrome P450 (CYP) 3A4 inhibitors (70.5%), digoxin (22.6%) or ciclosporin (cyclosporine) [1.6%]. The proportion of patients with a potential drug-statin interaction was 12.1% for simvastatin, 10.0% for atorvastatin, 3.8% for fluvastatin and 0.3% for pravastatin. Additionally, the program identified 393 potentially critical non-statin DDIs in 288 patients. CONCLUSIONS: CYP3A4 inhibitors are the most frequent cause of potential drug interactions with statins. As the risk for developing rhabdomyolysis is increased in patients with drug-statin interactions, clinicians should be aware of the most frequently observed drug-statin interactions and how these interactions can be avoided. 相似文献