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61.
Mitral inflow velocities are widely used for the evaluation of left ventricular (LV) diastolic function. However, they are closely affected by other factors such as preload. The purpose of this study was to evaluate the usefulness of tissue Doppler velocities obtained from the mitral annulus for the evaluation of ventricular relaxation in patients under different loading conditions. We also evaluated the effect of preload at different sides on the mitral annulus. The study population consisted of 62 consecutive patients (38 male, 24 female with a mean age of 42 ± 13 years) who have undergone hemodialysis. Both mitral inflow velocities (E wave, A wave, E wave deceleration time and isovolumetric relaxation time) and mitral annulus tissue Doppler velocities (E, A) from the septal, lateral, anterior, posterolateral and inferior sides of the mitral annulus were measured immediately before and after hemodialysis. Mitral inflow E and A wave velocities and E/A ratio decreased significantly (p < 0.001, p = 0.007, p < 0.001, respectively) after hemodialysis. Mitral annulus E wave velocities and E/A ratios obtained from five different sides of the annulus also changed significantly (p < 0.001 for all); however, there was no change in the A wave velocity (p > 0.05 for all) after hemodialysis. The decrease in E wave and E/A ratio in mitral inflow measurements and E velocities and E/A ratios in tissue Doppler measurements were correlated with the amount of fluid extracted (for mitral inflow E wave, r = 0.392, p = 0.002 and E/A ratio, r = 0.280 and p = 0.027; for lateral side E, r = 0.329, p = 0.009 and E/A ratio, r = 0.286, p = 0.04; for septal side E, r = 0.376, p = 0.003 and E/A ratio, r = 0.297, p = 0.019; for anterior side E, r = 0.342, p = 0.007 and E/A ratio, r = 0.268, p = 0.035; for posterolateral side E, r = 0.423, p = 0.001 and E/A ratio, r = 0.343, p = 0.007; and for inferior side E, r = 0.326, p = 0.01 and E/A ratio, r = 0.278, p = 0.029). We conclude that mitral annular velocities obtained by tissue Doppler are preload dependent parameters for the evaluation of LV diastolic function.  相似文献   
62.
The rupture of an intracranial aneurysm leads to subarachnoid hemorrhage (SAH). To prevent SAH, unruptured lesions can be treated by either endovascular or microsurgical approach. Due to their complex anatomy, middle cerebral artery (MCA) aneurysms represent a unique subgroup of intracranial aneurysms. Primary objective was to determine radiological and clinical outcomes in patients with middle cerebral artery aneurysms who were interdisciplinary treated by either endovascular or microsurgical approach in a single center. Secondary objective was to determine the impact of the lesions’ angiographic characteristics on treatment outcome. Clinical and radiological data of 103 patients interdisciplinary treated for unruptured MCA aneurysms over a 5-year period were analyzed in endovascular (n?=?16) and microsurgical (n?=?87) cohorts. Overall morbidity (Glasgow Outcome Score <5) after 12-month follow-up was 9 %. There was no significant difference between the two cohorts. Complete or “near complete” aneurysm occlusion was achieved in 97 and 75 % in the microsurgical, respective endovascular cohort. A “complex” aneurysm configuration had a significant impact on complete aneurysm occlusion in both cohorts, however, not on clinical outcome. Treatment of unruptured MCA aneurysms can be performed with a low risk of repair using both approaches. However, the risk for incomplete occlusion was higher for the endovascular approach in this series.  相似文献   
63.
64.
OBJECTIVE: To investigate the effects of long-term levothyroxine (LT4) suppressive therapy on the heart and the effects of beta-blockade on cardiac functions. DESIGN: Twelve female patients receiving LT4, selected from a group of patients with TSH levels of 0.1-0.4 microU/ml, were evaluated. The control group consisted of 11 healthy subjects and 12 patients with TSH levels <0.05 microU/ml. METHODS: Cardiac evaluation consisted of a 12-lead electrocardiogram and an echocardiographic study. Left ventricular mass index (LVMI), isovolumetric relaxation time (IVR), left ventricular end systolic (LVESD) and diastolic diameters, early (VE) and late (VA) diastolic flow velocities and fractional shortening were evaluated. Exercise capacity was assessed with a bicycle ergometer. Both work load and maximal exercise time were measured. Atenolol was given to the patient group at a dosage of 50 mg/day for 3 months and evaluations were repeated. RESULTS: On basal evaluations, LVMI (96+/-17 vs 78+/-21 g/m(2)) and IVR (101+/-9 vs 91+/-4 ms) were found to be increased in the patients taking LT4 (P<0.01). LVESD was also lower than controls (P<0.05). A decrease in VE and an increase in VA were also observed in the patients (P<0.01). IVR decreased after atenolol (92+/-10 vs 101+/-9 ms, P<0.05). LVMI decreased and VE and VA improved but did not reach statistical significance after beta-blockade. Baseline work load and maximal exercise duration were significantly lower in the patients and improvements were observed after atenolol treatment. CONCLUSIONS: These results indicated that cardiac dysfunction may occur even when TSH is suppressed to 0.1-0.4 microU/ml with LT4. beta-blockade improved the cardiac functions.  相似文献   
65.
Sporn  LA; Marder  VJ; Wagner  DD 《Blood》1987,69(5):1531-1534
Large multimers of von Willebrand factor (vWf) are released from the Weibel-Palade bodies of cultured endothelial cells following treatment with a secretagogue (Sporn et al, Cell 46:185, 1986). These multimers were shown by immunofluorescent staining to bind more extensively to the extracellular matrix of human foreskin fibroblasts than constitutively secreted vWf, which is composed predominantly of dimeric molecules. Increased binding of A23187-released vWf was not due to another component present in the releasate, since releasate from which vWf was adsorbed, when added together with constitutively secreted vWf, did not promote binding. When iodinated plasma vWf was overlaid onto the fibroblasts, the large forms bound preferentially to the matrix. These results indicated that the enhanced binding of the vWf released from the Weibel-Palade bodies was likely due to its large multimeric size. It appears that multivalency is an important component of vWf interaction with the extracellular matrix, just as has been shown for vWf interaction with platelets. The pool of vWf contained within the Weibel-Palade bodies, therefore, is not only especially suited for platelet binding, but also for interaction with the extracellular matrix.  相似文献   
66.
Endotoxin is a component of gram-negative bacteria that causes hematologic and immunologic changes through its induction of cytokines. Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring inhibitor of IL-1 that competes with IL-1 for occupancy of cell-surface receptors but possesses no agonist activity. We investigated the ability of human recombinant IL-1Ra to block the effects of low-dose endotoxin. Fourteen healthy male volunteers between 18 and 30 years old were injected intravenously with 3 ng/kg Escherichia coli endotoxin. Concurrent with the injections, nine volunteers received a 3-hour continuous intravenous infusion of IL-1Ra. The other five subjects were given a 3-hour infusion of saline. Volunteers injected with endotoxin experienced a threefold increase in circulating neutrophils over baseline. This neutrophilia was significantly reduced by 48% in subjects administered endotoxin plus IL-1Ra (P = .0253). Ex vivo mitogen-induced peripheral blood mononuclear cell proliferation decreased by greater than 60% at 3 and 6 hours after endotoxin injection (P = .0053). This endotoxin-induced reduction in mitogen response was reversed in subjects coinjected with IL-1Ra (P = .0253). Endotoxin-induced symptoms, fever, and tachycardia were unaffected by IL-1Ra. IL-1 appears to be an important mediator in endotoxemia because some of its hematologic and immunomodulatory effects can be blocked by IL-1Ra.  相似文献   
67.

Background:

Volar and/or dorsal surgical approaches are used for surgical treatment of perilunate and lunate dislocations. There are no accepted approaches for treatment in the literature. We evaluated the functional results of isolated volar surgical approach for the treatment of perilunate and lunate dislocation injuries.

Materials and Methods:

9 patients (6 male and 3 female patients average age 34.5 ± 3.6 years) diagnosed with perilunate or lunate dislocations between January 2000 and January 2009 were involved in the study. The reduction was performed through isolated volar surgical approach and K-wire fixation, fracture stabilization with volar ligament repair was performed. Range of wrist joint motion, fracture healing, carpal stability, grip strength, return to work were evaluated and also direct radiographs were taken routinely at each control. The scapholunate interval and the scapholunate angle were evaluated radiographically. Evaluations of the clinical results were done using the DASH, VAS and Modified Mayo Wrist Scores.

Results:

The physical rehabilitation was started at 6th week, after the K-wires were removed. The average followup was 18.2 months (range 12-28 months). At the final followup, the average flexion extension arc was 105.0 ± 9.6° (74.6% of the other side), the average rotation arc was 138.8 ± 7.8° (81.5% of the other side) and the average radioulnar arc was 56.1 ± 9.9° (86.4% of the other side). The grip strength was 0.55 bar; 83.2% that the uninjured arm. According to the Mayo Modified Wrist score, the functional result was excellent in five patients and good in four and the average DASH score was 22.8. The scapholunate interval was 2.1 mm and scapholunate angle was 51°.

Conclusion:

The clinical and radiological results of the isolated volar surgical approach were satisfactory. The dorsal approach was not needed for reduction of dislocations during operations. Our results showed that an isolated volar approach was adequate.  相似文献   
68.
69.
A 28-year-old woman underwent a pylorus preserving Whipple procedure for pancreatic serous cystadenoma located on the head of the pancreas. During the operation, an internal stent (7F silastic catheter, 9 cm in length) was placed within the pancreatic duct in the area of pancreaticojejunal end-to-end Dunking type anastomosis to prevent development of fistula. The stent was positioned so that one third of its length would lie into the pancreatic duct, and it was anchored to the periductal pancreatic tissue with only one rapidly absorbable chromic suture. Leakage from the anastomosis was not observed, and she was discharged without any complaint. Early postoperative abdominal CT examination revealed that the stent was retained within the normal caliber pancreatic duct (Fig. 1a). Six months after the operation, she began to complain to epigastric pain triggered by the meals. The laboratory analysis was normal, particularly liver biochemical tests and serum amylase. The internal pancreatic stent within the dilated pancreatic duct was detected by an additional CT examination (Fig. 1b). The stent was removed endoscopically at the third attempt. The pain was resolved after its removal. Control CT examination which was taken at the 18th month after removal of the stent showed dilatation of the pancreatic duct (Fig. 2a). The patient remained free of any complaint, although regressed pancreatic duct dilatation has persisted over 4 years of follow-up (Fig. 2b).  相似文献   
70.
PURPOSE OF REVIEW: To discuss the relationship between endometriosis and infertility, the impact of endometriosis on assisted reproductive techniques and also the benefits of prolonged use of gonadotropin-releasing hormone analogue before IVF in women with endometriosis. RECENT FINDINGS: The available evidence suggests that endometriosis is strongly associated with infertility. Many studies indicate lower pregnancy and implantation rates even in assisted reproductive cycles in women with endometriosis. It is well known that medical suppression of endometriosis does not appear to be warranted for endometriosis-associated infertility. Prolonged pretreatment with gonadotropin-releasing hormone analogue before IVF has been reported to improve clinical pregnancy rates in infertile women with endometriosis. SUMMARY: Based on the recently published data, infertile women with endometriosis may benefit from long-term pretreatment of gonadotropin-releasing hormone analogue prior to IVF.  相似文献   
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