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81.
PURPOSE: To develop a method for quantifying left ventricular (LV) internal flow as a measure of dyssynchrony using standard cine cardiac magnetic resonance (CMR) images. MATERIALS AND METHODS: CMR images were obtained from 10 healthy controls and 10 patients with dyssynchronous heart failure (class III/IV, LV ejection fraction <35%, pattern seen in an electrocardiogram QRS duration > 150 msec). The LV volume was reconstructed and divided into 16 regions. Internal flow was defined as the sum of the regional volume changes minus the global volume change during each time step in the cardiac cycle. Internal flow fraction (IFF) was defined as the total internal flow as a percentage of stroke volume during systole (IFF(systole)), diastole (IFF(diastole)), or the whole cycle (IFF(whole)). RESULTS: IFF(whole) was significantly increased in the patients (9.9 +/- 5.0% vs. 1.5 +/- 0.5% in the controls, P < 0.001). An IFF(whole) threshold of 4% discriminated between patients and controls with 90% sensitivity and 100% specificity. IFF(diastole) (2.3 +/- 0.8%) was greater than IFF(systole) (0.8 +/- 0.5%) in the normal controls (P < 0.001) while the patients had similar IFF(diastole) (7.8 +/- 4.2%) and IFF(systole) (12.0 +/- 7.8%). CONCLUSION: Left ventricular internal flow fraction can be quantified from standard CMR images. In this preliminary study, Left ventricular internal flow fraction discriminated patients with dyssynchronous heart failure from normal controls with 95% accuracy.  相似文献   
82.
OBJECTIVE: The purpose of this study was to determine the rate of progression of midventricular obstruction in adolescents and adults with double-chambered right ventricle. METHODS: Clinical and echocardiographic findings in 45 patients (mean age 26 +/- 6 years, range 15-44) diagnosed with double-chambered right ventricle were retrospectively analyzed. Twenty patients underwent surgical repair before the age of 15 years. The relationship between Doppler midventricular pressure gradient and patient age was analyzed in 25 patients without previous repair. Sequential change in midventricular obstruction was determined for patients with 2 or more Doppler echocardiographic examinations performed within at least a 2-year interval. RESULTS: Right midventricular pressure gradient in nonrepaired patients was 70 +/- 38 mm Hg (range 25-150). A significant relationship between midventricular obstruction and patient age (r = 0.64, P <.001) was found. Midventricular pressure gradient at initial evaluation was 32 +/- 27 mm Hg in 16 patients < 25 years and 73 +/- 45 mm Hg in 9 patients >/= 25 years (P <.03). After the initial study, 5 patients underwent surgical repair and 13 patients without repair were followed up for a period of 6.1 +/- 2.7 years (range 2-9), in which midventricular pressure gradient increased from 32 +/- 26 mm Hg to 67 +/- 35 mm Hg (P <.001). The slope of the change in midventricular pressure gradient was 6.2 +/- 3 mm Hg per year of follow-up. Seven more patients underwent surgical repair during follow-up due to progression of the obstruction. There was no mortality nor residual midventricular obstruction in surgically repaired patients. CONCLUSIONS: Mild right midventricular obstruction shows a fast rate of progression in adolescents and young adults. Thus, close clinical and echocardiographic follow-up is advised, and surgical repair should be considered if significant progression of obstruction is detected.  相似文献   
83.
The Sauvé–Kapandji (SK) procedure is indicated in distal radius nonunion or malunion and distal radioulnar joint (DRUJ) instability. It can also be used to treat the rheumatoid wrist with severe degenerative changes in the DRUJ. The main objective is to allow a pain-free range of movement. We present a patient with rheumatoid arthritis and distal radius nonunion who, after three operations, was treated with the SK procedure. The clinical and radiological results were excellent. A 53-year-old woman diagnosed with rheumatoid arthritis fell on her forearm at home 2 years ago. Examination at an outpatient clinic revealed a distal radius fracture classified as type V according to the Frykman classification. She had been operated three times with open reduction internal fixation using a plate, screws, and bone allograft. She came to our institution with a distal radius nonunion, positive post-traumatic ulnar variance, and ulnar nerve paresis. The range of movements was 20°–10° flexion-extension and 40°–30° pronation–supination, and she needed daily fentanyl. We performed a modified SK procedure with an autologous iliac crest bone graft and ulnar bone graft from the osteotomy area (cubitus proradius), bone morphogenetic protein, and a low profile distal radius plate. After 1 year of follow-up, the distal radius fracture has healed and the wrist is pain-free with a complete range of movement in flexion-extension and pronation-supination. The main indication for the SK procedure is post-traumatic positive ulnar variance and associated ulnocarpal impaction. The cubitus proradius bone graft transposition is an interesting technical note that makes this case a challenge for skilled orthopedic hand surgeons.  相似文献   
84.
85.
A wandering gallbladder typically is attached to surrounding structures only by the cystic duct and its mesentery. Its characteristic propensity for torsion places it at risk for necrosis. A 70-year-old woman admitted to our hospital was found to have a wandering gallbladder. The possible clinical implications of this finding are discussed.  相似文献   
86.
BACKGROUND/AIM: Alport syndrome is a hereditary glomerulonephritis, X-linked in 85% of the cases. This form is associated with mutations in the COL4A5 gene which encodes the alpha5 chain of type IV collagen. We have performed the mutational analysis of the COL4A5 gene in a Spanish family with X-linked Alport syndrome. METHODS: We have analyzed three polymorphic markers close to the gene to confirm the X chromosome linkage. By means of the PCR technique, we have screened the 51 exons of the gene. RESULTS: The segregation of the alleles from the analyzed markers was in agreement with the X linkage. Direct sequencing of PCR-amplified products has shown a CCT-to-CTT change in exon 25, resulting in substitution of a proline for a leucine at position 619 of the polypeptide chain (nucleotide 2058). CONCLUSIONS: Although proline is considered a nonconserved amino acid, it is essential, upon hydroxylation, in the maintenance of a stable alpha chain triple-helix collagen. Furthermore, the change cosegregates with the disease in all affected members of the family, not being present in 80 control chromosomes. This represents a new mutation in the COL4A5 gene found in the Spanish population.  相似文献   
87.
Proteinuria in the general population has been shown to be associated with cardiovascular disease, which is the main cause of death in renal transplantation. We investigated the effect of proteinuria on cardiovascular disease after renal transplantation in 532 renal transplant patients with functioning grafts for more than 1 year. Patients were classified into two groups depending on the presence of persistent proteinuria. We analyzed graft and patient survival, posttransplantation cardiovascular disease, and main causes of graft loss and death. Five- and 10-year graft and patient survival rates were lower in the group with proteinuria. The main cause of death was vascular disease in both groups. The presence of posttransplantation cardiovascular disease was higher in the group with proteinuria. Persistent proteinuria was associated with graft loss (RR=4.18), patient death (RR=1.92), and cardiovascular disease (RR=2.45). In conclusion, persistent proteinuria was an independent risk factor for increased cardiovascular morbidity and mortality in renal transplant patients.  相似文献   
88.
The exact moment to return to dialysis when a graft fails has not clearly been established. Furthermore, there is no agreement with respect to whether the guidelines accepted for patients entering dialysis for the first time are adequate for this subgroup of patients with advanced renal failure, due to the special characteristics of these patients, derived from the immunosuppressive medications they are taking among other accompanying factors. We reviewed a group of renal transplant patients who returned to dialysis and compared them with a group of patients entering dialysis for the first time. Patients with chronic renal failure due to graft failure had a poorer renal function at the time entering dialysis and a more profound anemia. Additionally, complications considered such as the number of hospital admissions during the first year after initiation of dialysis were considerably higher in the group of transplanted patients. We advocate for an earlier referral to the dialysis unit, a more aggressive erythropoietin therapy in the phase of advanced renal failure due to chronic allograft nephropathy, and in selected cases retransplantation before definitive graft loss.  相似文献   
89.
OBJECTIVE: Recent studies have suggested that endogenous vasopressin (AVP) acts as a spasmogen during coronary artery bypass grafting (CABG). Given that AVP could induce vasospasm in the grafted vessel, we assessed the release of this peptide during and after CABG, and explored ways of counteracting its contractile effect on the internal mammary artery (IMA). METHODS: Plasma levels of AVP were determined by radioimmunoassay in 16 patients before, during and after CABG. Using isometric force recording techniques, we also investigated the mechanisms involved in the contractile effect of AVP in ring preparations of IMA specimens taken from 95 patients. RESULTS: Plasma AVP levels peaked after the start of cardiopulmonary bypass (CPB) and correlated well with serum osmolality (Pearson's r=0.9490; P<0.0001; n=16). An inverse correlation was observed between plasma AVP levels recorded at this stage and the maximal contraction induced in vitro by AVP in vascular rings from the same patients (Pearson's r=-0.6968; P<0.01; n=16). No change in the AVP response was produced by endothelium removal, exposure to the NO precursor (3 x 10(-4)M L-arginine), inhibition of nitric oxide (NO) synthase (3 x 10(-5) M L-NAME) or soluble guanylate cyclase (3 x 10(-6) M 1H-[1,2,4]oxadiazol [4,3,-alpha]quinoxalin-1-one (ODQ)), removal of the superoxide anion (100 U/ml superoxide dismutase (SOD) plus 1200 U/ml catalase) or hydroxyl radical (10(-4) M deferoxamine), or specific alpha1 - (10(-6) M prazosin) or endothelin (10(-5) M bosentan) receptor antagonism. In contrast, adenylate cyclase activation (3 x 10(-8) M forskolin) reduced the contractile response to AVP, while prostanoid synthesis (3 x 10(-6) M indomethacin) inhibition and blockade of Ca2+ -activated potassium channels (KCa) (10(-3) M tetraethylammonium (TEA)) enhanced AVP contraction. Age, gender and smoking also modified the AVP response. CONCLUSION: Our findings suggest a role for AVP as a modulator of vascular tone in human IMA. The effect of AVP is dependent on prostanoids and Ca2+ -activated K+ channels, so its dysfunction in pathophysiological cardiovascular processes could mean that AVP, among other factors, produces vasospasm in IMA grafts.  相似文献   
90.
The purpose of this study was to determine the efficacy of women with breast cancer as teachers of the importance of breast cancer screening to their first-degree female relatives. The sample was restricted to low-income working age women recruited from four hospitals. The study design was a randomized clinical trial. At each hospital, breast cancer patients (probands) were randomized into one of two study groups: (i) intensive, individual educational training on breast cancer screening or (ii) standard clinic education on breast cancer screening. The probands were instructed to teach at least one of their first-degree female relatives (21+ years of age) about breast cancer screening techniques. Three to six months after the enrollment of the probands, their relatives were contacted by telephone to determine breast cancer screening practices. A total of 79 probands and 96 relatives participated in the study. Relatives in the education group when compared with the control group were: 1.25 times more likely to have clinical breast examination (p = 0.005), 2.83 times more likely to have scheduled a clinical breast examination (p = 0.046), and, 1.36 times more likely to have been told about performing breast self-examination (p = 0.05). Additionally, relatives in the education group were more likely to have received a pamphlet on breast cancer screening (RR = 1.58, p = 0.009) and have discussed the importance of breast cancer screening (RR = 1.33, p = 0.020) from the proband. Special education training did not impact mammography utilization of the relatives. From these findings, a tri-ethnic group of low-income women with breast cancer can be effective teachers of breast cancer screening practices, at least for promoting clinical breast examination and transmitting messaging for performance of breast self-examination if given the adequate training.  相似文献   
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