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51.
G. Mari P. De Nardi A. Zerbi G. Balzano L. Zannini A. Marassi V. Di Carlo 《Surgical endoscopy》1995,9(10):1119-1122
A teaching course in laparoscopic surgery was addressed to 21 young postgraduates as a part of their general surgery program with the aim of making them familiar with the basic principles of laparoscopic surgery. The methodology was based on tutorial teaching and learning by problems; the students worked in little groups elaborating check lists, discussing problems, and practising with laparoscopic training devices. Theoretical learning, practical abilities, and efficacy of tutorial teaching were investigated at the end of the course: the participant's understanding of instrument function, mastering of equipment, and solutions to clinical problems were good, as were the efficiency and pleasantness of the didactic method. Tutorial teaching seems to be a valid model for basic training in laparoscopic surgery in a modern medical education program. 相似文献
52.
53.
Perioperative immunonutrition in patients undergoing cancer surgery: results of a randomized double-blind phase 3 trial 总被引:24,自引:0,他引:24
Braga M Gianotti L Radaelli G Vignali A Mari G Gentilini O Di Carlo V 《Archives of surgery (Chicago, Ill. : 1960)》1999,134(4):428-433
HYPOTHESIS: Perioperative administration of a supplemented enteral formula may reduce the rate of postoperative infections. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: Department of surgery at a university hospital. PATIENTS: Two hundred six patients with neoplasm of colorectum, stomach, or pancreas. INTERVENTION: Patients were randomized to drink 1 L/d of either a control enteral formula (n = 104) or the same formula enriched with arginine, RNA, and omega3 fatty acids (n = 102) for 7 consecutive days before surgery. The 2 diets were isoenergetic and isonitrogenous. Jejunal infusion with the same formulas was started 6 hours after operation and continued until postoperative day 7. MAIN OUTCOME MEASURES: Rate of postoperative infectious complications and length of hospital stay. RESULTS: Both groups were comparable for age, sex, weight loss, Karnofsky scale score, nutritional status, hemoglobin level, duration of surgery, blood loss, and rate of homologous transfusion. Intent-to-treat analysis showed a 14% (14/102) infectious complication rate in the supplemented group vs 30% (31/104) in the control group (P = .009). In the eligible population, the postoperative infection rate was 11% (9/85) in the supplemented group vs. 24% (21/86) in the control group (P = .02). The mean +/- SD length of postoperative stay was 11.1+/-4.4 days in the supplemented group and 12.9+/-4.6 in the control group (P = .01). CONCLUSION: Perioperative administration of a supplemented enteral formula significantly reduced postoperative infections and length of stay in patients undergoing surgery for cancer. 相似文献
54.
The shoulder joint constitutes a sophisticated compromise between stability and movement: trauma such as dislocation and the surgery that follows to restore anatomical integrity, may cause a change in this balance, resulting in myofascial retraction, neuromotorial inhibition, and a deviation in motorial programming with the appearance of compensation. It is the purpose of this study to report the results obtained with a specific rehabilitation program in 18 patients submitted to Neer capsuloplasty to treat anterior shoulder instability. An objective and subjective study with pre-established stages, and a 12-month follow-up was done, to evaluate the results obtained based on the Rowe scale. 相似文献
55.
Free fatty acids impair hepatic insulin extraction in vivo 总被引:11,自引:0,他引:11
Wiesenthal SR Sandhu H McCall RH Tchipashvili V Yoshii H Polonsky K Shi ZQ Lewis GF Mari A Giacca A 《Diabetes》1999,48(4):766-774
Hyperinsulinemia is a common finding in obesity and results from insulin hypersecretion and impaired hepatic insulin extraction. In vitro studies have shown that free fatty acids (FFAs), which are often elevated in obesity, can impair insulin binding and degradation in isolated rat hepatocytes. To investigate whether FFAs impair hepatic insulin extraction (E(H)) in vivo, either saline (SAL) or 10% Intralipid (0.03 ml x kg(-1) x min(-1)) plus heparin (0.44 U x kg(-1) x min(-1)) (IH) was infused into normal dogs to elevate FFA levels. Insulin was infused intraportally at 18 pmol x kg(-1) x min(-1) for 150 min (period A, high insulin dose), and then at 2.4 pmol x kg(-1) x min(-1) for another 150 min (period B, low insulin dose). After the low portal insulin dose, additional insulin was infused peripherally at 8.4 pmol x kg(-1) x min(-1) for 120 min (period C) to assess the clearance of insulin from the peripheral plasma. In 16 paired experiments, FFA levels were 1,085 +/- 167, 1,491 +/- 240, 1,159 +/- 221 micromol/l (IH) and 221 +/- 44, 329 +/- 72, 176 +/- 44 micromol/l (SAL) in periods A, B, and C, respectively. Peripheral insulin levels were greater with IH (P < 0.001) than with SAL in all periods (1,620 +/- 114, 126 +/- 12, 1,050 +/- 72 pmol/l for IH vs. 1,344 +/- 168, 96 +/- 4.2, 882 +/- 60 pmol/l for SAL). Glucose clearance was impaired by IH in all periods (P < 0.05), whereas glucose production was slightly increased by IH during period B. Peripheral insulin clearance (Cl) and E(H) were calculated from the insulin infusion rate and insulin concentration data in each period by taking into account the nonlinearity of insulin kinetics. Cl was lower (P < 0.01) with IH (9.6 +/- 0.6, 12.0 +/- 0.9, 10.2 +/- 0.6 ml x kg(-1) x min(-1)) than with SAL (11.2 +/- 1, 13.6 +/- 0.7, 11.9 +/- 0.9 ml x kg(-1) x min(-1)) in periods A, B, and C. E(H) was also lower (P < 0.05) with IH (25 +/- 4, 40 +/- 5, 32 +/- 5%) than with SAL (30 +/- 2.8, 47 +/- 3, 38 +/- 3%). We conclude that FFAs can impair hepatic insulin extraction in vivo at high and low insulin levels, an effect that may contribute to the peripheral hyperinsulinemia of obesity. 相似文献
56.
Jovanović D Kovacević Z Zecević R Dimitrijević J Romanović R Marić M 《Vojnosanitetski pregled. Military-medical and pharmaceutical review》1999,56(5):551-554
In female patient, aged 41, 3 years ago appeared skin changes of urticarial type, and occasional pain in the joints of shoulders and hands, followed by complete weakness and exhaustion, as well as the occurrence of face and eyelid edema. Laboratory findings confirmed the presence of hypocomplentemia with proteinuria, microhematuria and cylindruria. Histopathologic (HP) finding of skin biopsy was leukocytoclastic vasculitis, and HP finding of the kidneys was mesangioproliferative glomerulonephritis. The regression of skin changes was observed during hospitalization after Dapsone was administered. The therapy started with corticosteroids (Prednisone 40 mg/day with weekly dose from 5 mg to 30 mg). In spite of the therapy, hypocomplementemia and proteinuria up to 335 mg/24 h have maintained for a year in the later controls in an outpatient department. The patient is without discomfort, and renal function is stable. 相似文献
57.
A number of flavone and xanthone derivatives bearing some characteristic features of fluoroquinolones such as the fluorine atom and an ortho piperazine ring are described. The new compounds have been tested for possible cytotoxic and antimicrobial activities. Cytotoxicity of both groups of compounds is rather poor, while the antibacterial activity is restricted to xanthones. 相似文献
58.
Magnetic fields (MF) can influence biological systems in a wide range of animal species and humans. We report here on the influence of static MF, locally applied to the brain area, on immune system performances in the rat. In the first series of experiments two AKMA micromagnets (M) with the influx density of 600 Gauss were bilaterally implanted (with "N" polarity facing the cranial bones) and fixed to the skull posterior to the fronto-parietal suture (parietal brain exposure). Rats implanted with iron beads (I) and sham-operated (SO) rats served as controls. Animals were exposed to MF or I during different periods of time before and after immunization with several soluble or cellular antigens. We report here on the in vivo immunoregulating effects of centrally applied MF on plaque-forming cell (PFC) response, local hypersensitivity skin reactions and experimental allergic encephalomyelitis. The selective influence of MF applied to different brain regions on PFC response was evaluated, as well. For this purpose, two M were bilaterally implanted in the area of (a) frontal, (b) parietal and (c) occipital brain regions. Rats were under the influence of MF for 20 days before and 4 days after immunization with sheep red blood cells. Groups of nonimmunized rats were exposed for 14, 24 and 34 days to parietally implanted M or I, and the number of peripheral blood CD4+ and CD8+ cells determined by mouse anti-rat W3/25 and MRC OX 8 monoclonal antibodies. The results show an overall in vivo immunopotentiation of humoral and cell-mediated immune responses in rats exposed to MF. Furthermore, these immunomodulating effects of centrally applied MF depend on at least two basic parameters, time of exposure and brain region exposed. The highest immune performance was obtained after exposure of the occipital brain region for a total period of 24 days. The results provide further evidence of the complex interrelationship between the environment, the central nervous system and the immune system. 相似文献
59.
Christel M. Olsen Elise T. M. Meussen‐Elholm Mari Samuelsen Jrn A. Holme Jan K. Hongslo 《Basic & clinical pharmacology & toxicology》2003,92(4):180-188
Abstract: Bisphenol A is extensively used in the manufacturing of epoxy resins and polycarbonate plastics, whereas several brominated and chlorinated analogues are used as flame retardants and intermediates in the plastic industry. Due to the structural relationship between these chemicals and the high production volumes, we wanted to characterize and compare their potential oestrogen‐like potency using several end‐points in MCF‐7 cells: induction of pS2 protein and progesterone receptor, reduction of oestrogen receptor level, and stimulation of cell growth. Bisphenol A, tetrachloro‐ and tetrabromo‐bisphenol A, 4‐hydroxybiphenyl and 4,4′‐dihydroxybiphenyl all showed oestrogen‐like properties in MCF‐7 cells. The chemicals tested had affinity to the oestrogen receptor isolated from MCF‐7 cells, although their EC50s were 1,000 to 80,000 times higher than the EC50 of 17β‐oestradiol. Bisphenol A and 4‐hydroxybiphenyl induced cell growth in MCF‐7 cells, and the highest test concentrations induced responses, apparently exceeding the cell growth induced by 17β‐oestradiol. The other chemicals tested induced less than 50% of the maximum 17β‐oestradiol‐stimulated cell growth. Bisphenol A, 4‐hydroxybiphenyl, tetrabromobisphenol A and tetrachlorobisphenol A all increased the level of the oestrogen‐regulated proteins, progesterone receptor and pS2, whereas 4,4′‐dihydroxybiphenyl showed no such effect. Bisphenol A was the only chemical tested that clearly mimicked 17β‐oestradiol in its ability to reduce the level of cytosolic oestrogen receptors in MCF‐7 cells. By measuring several oestrogen‐dependent endpoints it seems that some xeno‐oestrogens cause an imbalanced oestrogen‐response. Their ability and potency in mimicking 17β‐oestrogen in one parameter is not necessarily accompanied by a similar effect in another oestrogen‐linked parameter. 相似文献
60.
F Graziano F Arduini A Ruzzo A Mandolesi I Bearzi R Silva P Muretto E Testa D Mari M Magnani M Scartozzi S Cascinu 《Annals of oncology》2004,15(3):489-492
BACKGROUND: Hypermethylation is studied as a new, relevant mechanism for silencing tumor suppressor genes. It is a potentially reversible epigenetic change and it is the target of novel anticancer compounds with demethylating activity. In this perspective, we investigated E-cadherin gene (CDH1) promoter hypermethylation in gastric carcinomas and its correlation with E-cadherin protein expression. METHODS: Consecutive cases of gastric carcinoma with assessable paraffin-embedded tumor blocks and paired normal mucosa were considered eligible for study entry. CDH1 promoter hypermethylation and E-cadherin protein expression were determined by methylation-specific polymerase chain reaction and immunohistochemistry, respectively. RESULTS: CDH1 promoter hypermethylation was found in 20 out of 70 gastric carcinomas and the epigenetic change occurred in the early, as well as in the locally advanced disease. In five cases, hypermethylation was also detected in the normal mucosa. Eighteen out of 20 hypermethylated tumors were of the diffuse histotype (P=0.0001). Of 24 tumors with reduced or negative E-cadherin expression, 19 were hypermethylated and 5 were unmethylated (P=0.0001). CONCLUSIONS: CDH1 promoter hypermethylation frequently occurs in gastric carcinomas of the diffuse histotype and it is significantly associated with downregulated E-cadherin expression. The knowledge on the hypermethylation status of tumor suppressor genes may be relevant to the development of demethylating drugs and novel chemopreventive strategies in solid tumors. 相似文献