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1.
This meta-analysis focuses on the accuracy of upgrading to clinically significant prostate cancer (PCa) by multiparametric magnetic resonance imaging-targeted biopsy (MRI-TB) versus systematic biopsy (SB). We searched the Medline, Embase, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, and Literatura Latino Americana em Ciências da Saúde databases through January 2020 for comparative, retrospective/prospective, paired-cohort, and randomized clinical trials with paired comparisons. The population consisted of patients with low-risk PCa in active surveillance with at least 1 index lesion on imaging. We evaluated the quality of evidence by using the Quality Assessment of Diagnostic Accuracy Studies-2 score. Group comparisons considered the differences between the area under the curve summary receiver operating characteristic curve in a 2-tailed method. We also compared the positive predictive value of the best single method (MRI-TB or SB) and the referral study test (combined biopsy, a combination of MRI-TB and SB). The meta-analysis included 6 studies enrolling 741 patients. The pooled sensitivity for the 2 groups was 0.79 (95% confidence interval, 0.74-0.83; I2 = 75%) and 0.67 (95% confidence interval, 0.63-0.74; I2 = 55.4%), respectively. The area under the curve for the MRI-TB and SB groups were 0.99 and 0.92 (P < .001), respectively. The positive predictive value for the MRI-TB and combined biopsy groups were similar. The accumulated evidence suggests better results for MRI-TB compared with SB. Therefore, use of MRI-TB alone may be preferable in patients in active surveillance harboring low-risk PCa.  相似文献   
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The aim of this study was to evaluate the acute effects of unilateral ankle plantar flexors static-stretching (SS) on the passive range of movement (ROM) of the stretched limb, surface electromyography (sEMG) and single-leg bounce drop jump (SBDJ) performance measures of the ipsilateral stretched and contralateral non-stretched lower limbs. Seventeen young men (24 ± 5 years) performed SBDJ before and after (stretched limb: immediately post-stretch, 10 and 20 minutes and non-stretched limb: immediately post-stretch) unilateral ankle plantar flexor SS (6 sets of 45s/15s, 70-90% point of discomfort). SBDJ performance measures included jump height, impulse, time to reach peak force, contact time as well as the sEMG integral (IEMG) and pre-activation (IEMGpre-activation) of the gastrocnemius lateralis. Ankle dorsiflexion passive ROM increased in the stretched limb after the SS (pre-test: 21 ± 4° and post-test: 26.5 ± 5°, p < 0.001). Post-stretching decreases were observed with peak force (p = 0.029), IEMG (P<0.001), and IEMGpre-activation (p = 0.015) in the stretched limb; as well as impulse (p = 0.03), and jump height (p = 0.032) in the non-stretched limb. In conclusion, SS effectively increased passive ankle ROM of the stretched limb, and transiently (less than 10 minutes) decreased muscle peak force and pre-activation. The decrease of jump height and impulse for the non-stretched limb suggests a SS-induced central nervous system inhibitory effect.

Key points

  • When considering whether or not to SS prior to athletic activities, one must consider the potential positive effects of increased ankle dorsiflexion motion with the potential deleterious effects of power and muscle activity during a simple jumping task or as part of the rehabilitation process.
  • Since decreased jump performance measures can persist for 10 minutes in the stretched leg, the timing of SS prior to performance must be taken into consideration.
  • Athletes, fitness enthusiasts and therapists should also keep in mind that SS one limb has generalized effects upon contralateral limbs as well.
Key words: Athletic training, exercise performance, exercise training, crossover, cross-education  相似文献   
4.
This study verified the relationship between the volume and microleakage of conventional and bonded amalgam restorations. Also, the microleakage influence of intermediate materials, substrates and the direction of sectioning was investigated. Fifty-six bovine incisors were selected. Standard Class V cavities were prepared in buccal and lingual surfaces. For each tooth, two cavity sizes were prepared, corresponding to two cavity volumes: one larger (A) and the other smaller (B). The cervical wall was located in cementum/dentin and the incisal wall in enamel. The teeth were distributed in four groups (n=28) according to the intermediate material employed (glass-ionomer cement, resin cement, adhesive system and copal varnish-control). The materials were applied following manufacturers' directions. After restoration, the teeth were submitted to thermal cycling. They were then immersed in a dye solution and sectioned in two directions inciso-cervical (IC) and mesio-distal (MD) sections to evaluate the microleakage. Data were subjected to non-parametric statistical analysis (Wilcoxon's paired test and Kruskal-Wallis test). No significant difference was found between the two cavity sizes. Leakage in enamel was statistically lower than in the cementum/dentin interface (p < 0.05). In some situations, glass-ionomer or resin cement lined amalgam restorations presented less dye leakage than copal varnish lined restorations (p < 0.05). No significant difference was observed in microleakage between IC or MD sectioning. Within the limitations of this study, it was concluded that cavity size and direction of section were not significant factors for microleakage, while substrate and intermediate materials had a significant effect on the sealing ability in amalgam restorations.  相似文献   
5.
The recent finding that ribavirin has a mutagenic capacity in a poliovirus replicon model pushing the virus into error catastrophe, provides a possible explanation for the remarkable synergistic effect of ribavirin when combined with interferon in the treatment of chronic hepatitis C virus (HCV)-infected patients. However, ribavirin-induced hypermutation resulting in loss of vital genetic information and viral clearance, does not occur during treatment of HCV-infected patients, as can be inferred from the lack of viral inhibition when treating HCV-infected patients with ribavirin alone. We therefore hypothesized that ribavirin induces mutations in the C-terminal part of the viral NS5A gene, a region found to be correlated with interferon sensitivity. Ribavirin-induced mutations resulting in the appearance of viral variants more sensitive to interferon would explain the synergistic effect of ribavirin when combined with interferon. To test this hypothesis we retrospectively analysed sequences of the C-terminal half of the NS5A gene before and during treatment in six HCV genotype 1-infected patients who had been treated with combination therapy after initial failure to respond permanently to interferon alone. Our results show that during the early treatment phase mutation rate is not enhanced during combination therapy and that, at least in the major variant, shifts in the NS5A domain resulting in the occurrence of viral variants, which are more interferon-sensitive, do not occur.  相似文献   
6.
The glomus tumor is a rare, benign, but painful vascular neoplasm arising from the neuromyoarterial glomus. Primary intraosseous glomus tumor is even rarer, with only about 20 cases reported in the literature so far, 5 of which involved the spine. Surgical resection is currently considered the treatment of choice. We herewith present an uncommon case of primary intraosseous spinal glomus tumor involving the right pedicle of the eleventh thoracic vertebra (T11). To our knowledge, this is the first case of primary intraosseous spinal glomus tumor successfully treated by percutaneous CT-guided radiofrequency ablation (RFA).  相似文献   
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8.
Random survey for RHD alleles among D+ European persons   总被引:1,自引:0,他引:1  
Chen Q  Flegel WA 《Transfusion》2005,45(7):1183-1191
BACKGROUND: RHD alleles are considered more variable in African persons than in European persons. A systematic survey, however, was lacking among D+ European persons at the molecular level, precluding any definite frequency estimate. STUDY DESIGN AND METHODS: A random survey was performed among 500 ccDee, 250 CcDee, and 250 ccDEe blood donors in southwestern Germany. They were tested by polymerase chain reaction with sequence-specific priming (PCR-SSP) for up to 12 single-nucleotide polymorphisms representative for the most frequent RHD alleles among European persons. The RHD exon 5 nucleotide sequence was also tested in all 1000 samples. The nucleotide sequence of the 10 RHD exons was checked in all samples with aberrant exon 5 or positive PCR-SSP procedures. RESULTS: By PCR-SSP, 15 aberrant RHD alleles were found among the 500 ccDee, 2 among the 250 CcDee, and none among the ccDEe samples. One of these was the novel RHD(F223V, E233Q, T379M) allele dubbed DAU-5. Weak D type 4 was detected more frequently than expected, whereas the population frequencies of the other RHD alleles conformed to published estimates. Nucleotide sequencing of RHD exon 5 further revealed three novel alleles RHD(G212G), RHD(R234W), and RHD(V245L), dubbed DUC-1, DQC, and DUC-2. CONCLUSION: In a limited screen at the molecular level among 1000 random D+ donors in southwestern Germany, 20 donors were found carrying aberrant RHD alleles. Four of these alleles were new and likely sporadic. An estimate was derived of the variety that may be encountered in genotyping approaches, and it was concluded that even within the European population the variety of RHD alleles may be larger than anticipated.  相似文献   
9.
The signaling lipid sphingosine-1-phosphate (S1P) stabilizes the vasculature, directs lymphocyte egress from lymphoid organs, and shapes inflammatory responses. However, little is known about how S1P distribution is controlled in vivo, and it is not clear how a ubiquitously made lipid functions as a signal that requires precise spatial and temporal control. We have found that lipid phosphate phosphatase 3 (LPP3) enables efficient export of mature T cells from the thymus into circulation, and several lines of evidence suggest that LPP3 promotes exit by destroying thymic S1P. Although five additional S1P-degrading enzymes are expressed in the thymus, they cannot compensate for the loss of LPP3. Moreover, conditional deletion of LPP3 in either epithelial cells or endothelial cells is sufficient to inhibit egress. These results suggest that S1P generation and destruction are tightly regulated and that LPP3 is essential to establish the balance.  相似文献   
10.
Approximately 10%-15% of couples are infertile, and a male factor is involved in almost half of these cases. This observation is due in part to defects in spermatogenesis, and the underlying causes, including genetic abnormalities, remain largely unknown. Until recently, the only genetic tests used in the diagnosis of male infertility were aimed at detecting the presence of microdeletions of the long arm of the Y chromosome and/or chromosomal abnormalities. Various other single-gene or polygenic defects have been proposed to be involved in male fertility. However, their causative effects often remain unproven. The recent evolution in the development of whole-genome-based techniques and the large-scale analysis of mouse models might help in this process. Through knockout mouse models, at least 388 genes have been shown to be associated with spermatogenesis in mice. However, problems often arise when translating this information from mice to humans.  相似文献   
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