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101.
102.
Background  Studies showing the improvement of insulin sensitivity by reducing the term of preoperative fasting are mostly done in patients undergoing major operations. More information about the role of shortened preoperative fasting in perioperative metabolism is needed for such elective minor/moderate abdominal procedures as laparoscopic cholecystectomy. We investigated the influence of a carbohydrate-rich drink given 2 h before laparoscopic cholecystectomy on insulin resistance and the metabolic response to trauma. Methods  A group of 21 female candidates (18–65 years old) for elective laparoscopic cholecystectomy were randomized to either an 8 h fasting group (control group: n = 10) or to a group receiving 200 ml of a carbohydrate beverage containing 12.5% (25 g, 50 kcal per 100 ml and approximately 285 mOsm) of maltodextrine 2 h before operation (CHO group: n = 11). Blood samples for various biochemical assays were collected both at induction of anesthesia and after the 10th postoperative hour. Insulin resistance was assessed by the HOMA-IR equation (Insulin (μU/ml) × blood glucose (mg/dl)/405). Results  There were no postoperative complications. Seventy percent (7/10) of the controls and 27.3% (3/11) of the CHO group experienced at least one episode of vomiting (RR = 2.42, 95% Confidence Interval [CI] = 0.88–6.68; P = 0.08). Biochemical analysis showed that serum glucose (P < 0.01), insulin (P < 0.01), lactate/pyruvate ratio (P = 0.03), and triglycerides (P < 0.01) for the control group were higher than for the CHO group. The value of HOMA-IR was significantly greater (P = 0.03) in the conventionally fasted patients than in the CHO group. Conclusions  Abbreviation of the period of preoperative fasting and administration of a carbohydrate beverage diminishes insulin resistance and the organic response to trauma.  相似文献   
103.

Purpose

Evaluate if gadolinium enhanced MR imaging (GeMRI) improves confidence, changes the final diagnosis, or improves accuracy in the assessment of musculoskeletal (MSK) tumor residual or recurrence following surgical resection. We also assess if different experience levels change the above results.

Methods and materials

Initially, pre-contrast images were independently reviewed by two radiologists, one with 25 years of experience (R1) and one undergoing MSK specialty training (R2). Two questions were answered: (1) Mass present? and (2) Likelihood of malignancy? Subsequently, both pre-contrast and post-contrast images were independently reviewed. The same questions were again answered plus four others including if GeMRI changed mass characterization, better defined cystic versus solid, better defined tumor extent, or improved conspicuity. Lastly, the readers answered whether GeMRI changed confidence, and changed their final diagnosis. Histologic diagnoses were available in 43 cases, with the remaining 44 cases based upon clinical and/or imaging follow-up.

Results

GeMRI definitely improved confidence in 8/7 cases, and slightly improved confidence in 20/29 cases and changed the final diagnosis in 11/8 cases for R1 and R2 respectively. Positive and negative predictive values statistically improved for R2 (positive predictive value 36.4% versus 50%, p = 0.02; negative predictive value 75.4% versus 79.1%, p = 0.04) but not for R1. Reader concordance for malignancy improved with GeMRI (κ = 0.44 pre-contrast and κ = 0.71 post-contrast).

Conclusion

GeMRI improved reader confidence, improved reader concordance and modestly improved accuracy for the less experienced reader. Where possible, GeMRI should be used in the assessment of MSK tumor residual or recurrence.  相似文献   
104.
Multicontrast magnetic resonance imaging (MRI) has shown promise in identifying and characterizing atherosclerotic plaques. One of the limitations of this technique is the lack of a practical automated plaque characterization scheme. In the current study, a prior-information-enhanced clustering (PIEC) technique that utilizes both multicontrast MR images and quantitative T(2) maps is proposed to characterize atherosclerotic plaque components automatically. The PIEC algorithm was assessed on computationally simulated images and multicontrast MRI data of coronary arteries. Multicontrast (T(1)-, T(2)-, partial T(2)-, and proton density-weighted) MR images were acquired from freshly excised human coronary arteries using a 4.7T small-animal scanner. The T(2) distribution for each plaque constituent was measured by exponentially fitting the signal from multiple MR images with different TEs and the same TR. The calculated T(2) distributions were used as the a priori information and combined with the Fuzzy C-Means (FCM)-based clustering algorithm to characterize plaque constituents. The proposed PIEC technique appears to be a promising algorithm for accurate automated plaque characterization.  相似文献   
105.
BACKGROUND: Previous linkage studies have suggested prostate cancer susceptibility genes located on chromosomes 1, 20, and X. Several putative prostate cancer candidate genes have also been identified including RNASEL, MSR1, and ELAC2. Presently, these linkage regions and candidate genes appear to explain only a small proportion of hereditary prostate cancer cases suggesting the need for additional whole genome analyses. METHODS: A genome-wide mode-of-inheritance-free linkage scan, using 405 genetic markers, was conducted on 175 pedigrees, the majority containing three or more affected individuals diagnosed with prostate cancer. Stratified linkage analyses were performed based on previously established criteria. RESULTS: Results based on the entire set of 175 pedigrees showed strong suggestive evidence for linkage on chromosome 17q (LOD = 2.36), with strongest evidence coming from the subset of pedigrees with four or more affected individuals (LOD = 3.27). Race specific analyses revealed strong suggestive evidence for linkage in our African-American pedigrees on chromosome 22q (LOD = 2.35). CONCLUSIONS: Genome-wide analysis of a large set of prostate cancer families indicates new areas of the genome that may harbor prostate cancer susceptibility genes. Specifically, our linkage results suggest that there is a prostate cancer susceptibility gene on chromosome 17 that is independent of ELAC2. Further research including combined analyses of independent genome-wide scan data may clarify the most important regions for future investigation.  相似文献   
106.
Partial splenectomy is an alternative to total splenectomy for the treatment of congenital hemolytic anemias (CHAs) in children, although the feasibility of this technique in the setting of massive splenomegaly is unknown. This study was designed to evaluate the safety and efficacy of partial splenectomy in children with CHAs and massive splenomegaly. This retrospective study examined 29 children with CHAs who underwent partial splenectomy. Children were divided into 2 groups based on splenic size: 8 children had splenic volumes greater than 500 mL, whereas 21 children had splenic volumes less than 500 mL. Outcome variables included perioperative complications, transfusion requirements, hematocrits, reticulocyte counts, bilirubin levels, splenic sequestration, and splenic regrowth. All 29 children underwent successful partial splenectomy with 0.02 to 10 years of follow-up. After partial splenectomy, children overall had decreased transfusion requirements, increased hematocrits, decreased bilirubin levels, decreased reticulocyte counts, and elimination of splenic sequestration. Children with massive splenomegaly had similar outcomes compared with children without massive splenomegaly. Long-term complications included 3 mild infections, 4 cases of gallstones requiring cholecystectomy, and 1 child who required completion splenectomy. Partial splenectomy is a safe, effective, and technically feasible option for children with various CHAs, even in the setting of massive splenomegaly.  相似文献   
107.
Pigment nephropathy accounts for approximately 3% of all cases of acute renal failure (ARF) in children. Studies of risk factors associated with ARF and the need for renal replacement therapy (RRT) in children with rhabdomyolysis-associated pigment nephropathy consist of retrospective case series with variable inclusion criteria. Our objective was to evaluate clinical and laboratory characteristics, etiology, initial fluid therapy, prevalence of ARF and the requirement for RRT in pediatric patients with acute rhabdomyolysis. Twenty-eight patients (19 male) with a mean age of 11.1 ± 5.6 years were studied. Acute renal failure occurred in 11 patients (39%), seven of whom (64%) required RRT. Features associated with the need for RRT included history of fever, persistent oliguria, admission blood urea nitrogen level, creatinine, Ca2+, K+, bicarbonate and aspartate aminotransferase. Most of these factors are related to the level of renal insufficiency and degree of muscle injury. There was no difference in admission and peak creatine kinase (CK) levels between those who did or did not require RRT. However, all who required RRT had a peak CK level > 5000 U/L.  相似文献   
108.
Introduction: The best treatment of IgA nephropathy (IgAN) is currently not well defined. The Supportive Versus Immunosuppressive Therapy of Progressive IgA Nephropathy (STOP IgAN) trial aims to answer if, in IgAN patients, an immunosuppressive treatment is more effective than a supportive treatment. Methods: In a randomized prospective multicenter study (www.clinicaltrials.gov, NCT00554502), we will treat 148 patients at risk for progressive IgA nephropathy following a 6-month run-in phase, in 2 groups: (group a) supportive treatment: patients with a persistent proteinuria >0.75 g/day will receive a maximized therapy to reduce blood pressure and urinary protein loss using angiotensin-converting enzyme inhibitors and AT1 blockers, statins, dietary counseling for a low-sodium and low-protein diet and education/intervention programs to stop smoking. (group b) immunosuppressive treatment: in addition to the identical treatment of group a, patients will receive treatment with steroids (glomerular filtration rate [GFR] > or =60 ml/min) or steroids plus cyclophosphamide/azathioprine (GFR <60 ml/min). Study end points are the complete remission of the disease and the individual degree of renal functional loss. If the immunosuppressive therapy shows a superior efficacy with respect to prevention of renal failure, the potentially higher therapy cost and risk might be justified. Finally, our trial can serve as a model for various other types of glomerulonephritis, for which such trials are very difficult to perform, given their infrequency.  相似文献   
109.
Cystic mesenchymal hamartoma is an extremely rare, benign tumor. Rapid growth to a giant size can pose a threat not only in early childhood but also during fetal life. The experience with 2 antenatally diagnosed giant hepatic cysts with widely disparate approaches to management, treatment, and outcome is presented. A giant hepatic cyst was diagnosed on routine screening ultrasound scan. Because of its extremely massive size, the cyst was treated in utero with repeated aspirations, primarily for obstetric considerations. The infant did well, and the lesion was excised laparoscopically during the neonatal period. A second fetus with a giant hepatic cyst was not treated in utero, and the pregnancy continued to term. Nonimmune hydrops fetalis developed, and the fetus was delivered prematurely at 34 weeks. At birth, the infant was noted to have diffuse neurologic injury and no urine output despite normal-appearing kidneys. The lesion was excised during the neonatal period by open laparotomy. Observations at the time of surgery and pathologic studies of the placenta showed aneurysmal dilatation of the placental veins suggesting in utero compression of the fetal intraabdominal umbilical vein. The infant died shortly after birth. The experience with these 2 cases suggests the possibility that giant mesenchymal hamartoma diagnosed in utero may cause umbilical venous obstruction leading to ischemia during fetal life. Decompression of giant hepatic cysts may reverse this phenomenon and allow normal fetal development. J Pediatr Surg 37:E31.  相似文献   
110.
BACKGROUND: Increased concentrations of very low- (VLDL) and intermediate-density (IDL) lipoproteins in chronic renal failure (CRF) are thought to result from a defect(s) in degradation of plasma triglyceride (TG)-rich lipoproteins. The purpose of this study was to identify lipoprotein abnormalities associated with the reduced lipolytic rate constant, k1, of combined VLDL and IDL substrate from renal patients and asymptomatic controls. METHODS: The VLDL + IDL were isolated from 18 predialytic patients (CRF-I), 8 patients on hemodialysis (CRF-II) and 10 asymptomatic controls. The lipolytic rate constant (k1) of VLDL + IDL was measured by an assay using bovine milk lipoprotein lipase and determination of TG before and after incubation by gas chromatography (GC). Neutral lipids were measured by GC and apolipoproteins by electroimmunoassays; the apolipoprotein-defined TG-rich lipoproteins including Lp-B:C, Lp-B:C:E and Lp-A-II:B:C:D:E were determined by immunoaffinity chromatography. RESULTS: The k1 values of VLDL + IDL were significantly (P < 0.001) lower in CRF-I and CRF-II patients (0.0341 and 0.0352 min-1, respectively) than controls (0.0515 min-1). The levels of apolipoproteins B, C-III and E, and TG-rich Lp-B:C, Lp-B:C:E and Lp-A-II:B:C:D:E particles normalized to 100 mg TG per VLDL + IDL were significantly higher in both groups of CRF patients than in controls. All three TG-rich lipoproteins were characterized by significantly increased percent contents of free (FC) and esterified (CE) cholesterol and a decreased percentage of TG. The k1 values of the combined CRF-I and CRF-II patient groups showed significant negative correlations (P < 0.001) with FC (r=-0.81) and CE (r=-0.63) and a positive correlation with TG (r=0.72). Among lipoprotein particles, only Lp-A-II:B:C:D:E levels showed a significant negative correlation with k1 values (r=-0.47, P < 0.03). CONCLUSIONS: This study shows that the abnormal neutral lipid composition of all three TG-rich lipoprotein particles and increased concentrations of Lp-A-II:B:C:D:E particles represent the main factors affecting the in vitro lipolytic rates of VLDL + IDL substrate in both the CRF patients before dialysis and patients on hemodialysis.  相似文献   
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