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91.
92.
Penile color Doppler sonography is a valuable method for evaluating erectile dysfunction. However, there are some concerns about the safety of this method due to the intracorporeal pharmacological injection, which may cause priapism as a complication, resulting in penile fibrosis. To evaluate the actual incidence of papaverine-induced priapism in patients with erectile dysfunction (ED) who underwent penile colour Doppler sonography and to determine the safety of this diagnostic tool, a retrospective study was conducted using the database of our institution. A total of 672 men with ED underwent penile color Doppler ultrasonography with the intracorporeal injection of 60 mg papaverine hydrochloride. The patient characteristics of priapism cases were retrospectively evaluated. Priapism in 18 of the 672 patients (2.68%) was successfully treated with blood aspiration, irrigation and injection of an α-agonist medication, when needed. Patients with priapism were younger compared with those without priapism; mean age 45 ± 12.51 (20–68) versus 50.93 ± 12.04 (17–78) ( P  < 0.001). Penile Doppler ultrasound is a safe procedure in evaluating erectile dysfunction. The incidence of priapism, which is the most important complication of this procedure, is low and can be managed successfully with conservative approaches.  相似文献   
93.
Objective: Currently, there is no overview of the incidence and (basketball-specific) risk factors of musculoskeletal injuries among recreational basketball players, nor any insight into the effect of preventive measures on the incidence of basketball injuries. This study aimed to gather systematically the scientific evidence on the incidence, prevalence, aetiology and preventive measures for musculoskeletal injuries among recreational basketball players.

Methods: Highly sensitive search strategies were built based on three groups of keywords (and related search terms). Two electronic databases were searched, namely Medline (biomedical literature) via Pubmed, and SPORTDiscus (sports and sports medicine literature) via EBSCOhost.

Results: The incidence of musculoskeletal injuries among recreational basketball players ranged from 0.0047 injuries per 1,000 athlete-exposures (AE) for dental injuries to 10.1 injuries per 1000 AE for overall injuries during match play. Significant risk factors for injuries were defending, postural sway, high vertical ground reaction force during jumping and weight >75 kg. All prevention studies have shown to have a significant effect on reducing the risk of injury ranging from an odds ratio (95% confidence interval (CI)) of 0.175 (0.049–0.626) for training injuries and a relative risk (95% CI) of 0.83 (0.57–1.19) achieved with FIFA 11+ prevention exercises and sport-specific balance training, relatively.

Conclusion: In order to gain insight in the aetiology of basketball-specific injuries and consequently facilitate the development of preventive strategies, more high quality basketball-specific and injury-specific studies among recreational basketball players are needed.  相似文献   

94.
The aim of this study was to evaluate whether electrical muscle stimulation (EMS) on dominant wrist flexors causes an increase in the muscle strength of the contralateral wrist extensors. Twenty-three healthy, young, adult men were included in this prospective, double-blind, controlled study. Participants were randomly allocated to the EMS group or Control group. Electrodes were placed over the flexor aspect of the right forearm in both groups. In the EMS group, passive wrist extension and (EMS) that caused powerful muscle contraction were simultaneously applied. In the Control group, a conventional mode of transcutaneous electrical nerve stimulation was applied without causing any contraction. A group effect (P=0.0001) and group-by-time interaction were found (P=0.0001) for both the wrist flexor and extensor muscles, but not group-by-time-by-arm interactions. This implies that the effect of the interventions was similar in both arms, but that the response was significantly larger in the EMS than in the Control group. The results of the current study suggest that cross-education is not confined to the untrained contralateral wrist flexors and that the strength increase may also be observed in the contralateral wrist extensors.  相似文献   
95.
In this work, we demonstrate the possibility to modify the electric‐field distribution of a radio frequency (RF) coil to generate electric field‐free zones in the body without significantly altering the transmit sensitivity. Because implant heating is directly related to the electric‐field distribution, implant‐friendly RF transmit coils can be obtained by this approach. We propose a linear birdcage transmit coil with a zero electric‐field plane as an example of such implant‐friendly coils. When the zero electric‐field plane coincides with the implant position, implant heating is reduced, as we demonstrated by the phantom experiments. By feeding RF pulses with identical phases and shapes but different amplitudes to the two orthogonal ports of the coil, the position of the zero electric‐field plane can also be adjusted. Although implant heating is reduced with this method, a linear birdcage coil results in a whole‐volume average specific absorption rate that is twice that of a quadrature birdcage coil. To solve this issue, we propose alternative methods to design implant‐friendly RF coils with optimized electromagnetic fields and reduced whole‐volume average specific absorption rate. With these methods, the transmit field was modified to reduce RF heating of implants and obtain uniform transmit sensitivity . Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
96.

Objectives

Evaluation of enhancement characteristics of histopathologically confirmed focal nodular hyperplasias (FNHs) and hepatocellular adenomas (HCAs) with gadoxetic acid-enhanced MRI.

Methods

Sixty-eight patients with 115 histopathologically proven lesions (FNHs, n?=?44; HCAs, n?=?71) examined with gadoxetic acid-enhanced MRI were retrospectively enrolled (standard of reference: surgical resection, n?=?53 patients (lesions: FNHs, n?=?37; HCAs, n?=?53); biopsy, n?=?15 (lesions: FNHs, n?=?7; HCAs, n?=?18)). Two radiologists evaluated all MR images regarding morphological features as well as the vascular and hepatocyte-specific enhancement in consensus.

Results

For the hepatobiliary phase, relative enhancement of the lesions and lesion to liver enhancement were significantly lower for HCAs (mean, 48.7 (±48.4) % and 49.4 (±33.9) %) compared to FNHs (159.3 (±92.5) %; and 151.7 (±79) %; accuracy of 89 % and 90 %, respectively; P?<?0.001). Visual strong uptake of FNHs vs. hypointensity of HCAs in the hepatobiliary phase resulted in an accuracy of 92 %. This parameter was superior to all other morphological and dynamic vascular criteria alone and in combination (accuracy, 54–85 %).

Conclusions

For differentiation of FNHs and HCAs by means of MRI, gadoxetic acid uptake in the hepatobiliary phase was found to be superior to all other criteria alone and in combination.

Key Points

? EOB-MRI is well suited to differentiate FNHs and hepatocellular adenomas. ? For this purpose hepatobiliary phase is superior to unenhanced and dynamic imaging. ? Hepatobiliary phase (peripheral) hyper- or isointensity is typical for FNH. ? Hepatobiliary phase hypointensity is typical for hepatocellular adenomas. ? EOB-MRI helps to avoid misinterpretations of benign hepatocellular lesions.  相似文献   
97.
Hyperlipidemia is a highly prevalent risk factor for coronary and cervical atherosclerosis and stroke. However, even in the absence of overt atherosclerosis, hyperlipidemia disrupts endothelial and smooth muscle function. We investigated the impact of hyperlipidemia on resting-brain perfusion, fundamental cerebrovascular reflexes, and dynamic perfusion defect during acute focal ischemia in hyperlipidemic apolipoprotein E knockout mice before the development of flow-limiting atherosclerotic stenoses. Despite elevated blood pressures, absolute resting cerebral blood flow was reduced by 20% in apolipoprotein E knockout compared with wild type when measured by [14C]-iodoamphetamine technique. Noninvasive, high spatiotemporal resolution laser speckle flow imaging revealed that the lower autoregulatory limit was elevated in apolipoprotein E knockout mice (60 vs. 40 mm Hg), and cortical hyperemic responses to hypercapnia and functional activation were attenuated by 30% and 64%, respectively. Distal middle cerebral artery occlusion caused significantly larger perfusion defects and infarct volumes in apolipoprotein E knockout compared with wild type. Cerebrovascular dysfunction showed a direct relationship to the duration of high-fat diet. These data suggest that hyperlipidemia disrupts cerebral blood flow regulation and diminishes collateral perfusion in acute stroke in the absence of hemodynamically significant atherosclerosis.  相似文献   
98.
Schizophrenia is a complex disorder with a polygenic inheritance. Catechol-O-methyltransferase (COMT) plays a significant role in the regulation of dopaminergic systems. A polymorphism at COMT Val108/158Met has been identified in association with schizophrenia. We examined the allele and genotype association of the COMT Val108/158Met polymorphism of 297 unrelated schizophrenic patients who strictly met DSM-IV criteria for schizophrenia, and 341 healthy controls. We found significant difference in allele and genotype frequencies between schizophrenic patients and controls (chi2=13.030; P=0.001). The allele frequency of the COMT-L was 45.79% in the total schizophrenic patients, and 41.50% in controls. The genotype frequency of the COM-LL was 21.2% in the total schizophrenic patients, and 11.4% in controls (OR=2.085; 95% CI=1.350-3.219; chi2=11.293; P=0.001). With a separate sex analysis, the frequency of the COMT-L allele was moderately distributed in male schizophrenia (chi2=6.177; df=2; P=0.046). The COMT-LL genotype had a 1.818-fold increased risk for schizophrenia (OR=1.818; 95% CI=1.010-3.273; chi2=4.048; P=0.044). The frequency of the COMT-L allele was even more significantly distributed in women schizophrenia (chi2=7.797; df=2; P=0.020). The COMT-LL genotype had remarkably more increased risk for schizophrenia (OR=2.456; 95% CI=1.287-4.687; chi2=7.710; P=0.005). In conclusion, our results provide strong evidence for a role of the COMT-L allele and LL genotype in the etiopathophysiology of schizophrenia with a sexual difference.  相似文献   
99.
We examined whether the GRIK3 (T928G) polymorphic variants in patients with schizophrenia are different from those of their first-degree relatives and healthy controls. The study population was composed of 256 patients with schizophrenia, 305 first-degree relatives of schizophrenia patients and 242 healthy control subjects. The GRIK3 (T928G) polymorphism was determined by restriction fragment length polymorphism. The frequency of the TT genotype was predominant, whereas the GG genotype was rare among all groups. The frequencies of GRIK3 (T928G) genotype distributions in the patients with schizophrenia were similar to those of their relatives. The frequency of the GG genotype was significantly higher in patients than in healthy controls. Similarly, GG genotype distribution in relatives was elevated compared with that in controls, but this value did not reach statistical significance. On the other hand, the subgroups of schizophrenia patients did not show a significant association with the GRIK3 (T928G) gene. It appears that the patients share the same (GRIK3) T928G gene variants with their relatives. One interpretation of our findings is that the relatives are at risk for the development of schizophrenia in the future.  相似文献   
100.
Using the transcranial Doppler technique to assess postnatal changes in cerebral blood flow velocity, we studied the anterior cerebral artery, middle cerebral artery, and internal carotid artery of 31 healthy, term newborn infants. Normative values for the 1st, 3rd, and 5th days of life were determined. Cerebral blood flow velocity values in all three arteries examined correlated well with each other and we observed a statistically significant increase only in middle cerebral artery blood flow velocity between the 1st and 3rd, and 1st and 5th postnatal days. Thus, if we assume that flow velocities in various cerebral arteries undergo similar change, only one representative artery need be examined. The middle cerebral artery appears to be the vessel of choice. This choice simplifies the recording procedure, particularly in repeated examinations.  相似文献   
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