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21.
Túlio Silva Pereira Raphael Castro Guimarães Douglas de DW. Oliveira Adriana Maria Botelho José Cristiano Ramos Glória 《Cranio : the journal of craniomandibular practice》2014,32(1):51-56
Aim:Low-level laser therapy has still not been well established, and it is important to define a standardized protocol for the treatment of temporomandibular disorders (TMDs) using low level laser. There is no consensus on controlled clinical trials concerning the best option for laser therapy with regard to wavelength. The aim of this study was to evaluate the efficacy of red and infrared laser therapy in patients with TMD, using a randomized parallel-group double-blind trial.Methodology:Each hemiface of 19 subjects was randomized to receive intervention, in a total of 116 sensitive points. Pain was measured at baseline and time intervals of 24 hours, 30 days, 90 days, and 180 days after treatment. Irradiation of 4 J/cm2 in the temporomandibular joints and 8 J/cm2 in the muscles was used in three sessions.Results:Both treatments had statistically significant results (P<0·001); there was statistical difference between them at 180 days in favor of the infrared laser (P?=?0·039). There was improvement in 24 hours, which extended up to 180 days in both groups.Conclusion:Both lasers are effective in the treatment and remission of TMD symptoms. 相似文献
22.
Identification of a novel hierarchy of endothelial progenitor cells using human peripheral and umbilical cord blood 总被引:48,自引:5,他引:48
Ingram DA Mead LE Tanaka H Meade V Fenoglio A Mortell K Pollok K Ferkowicz MJ Gilley D Yoder MC 《Blood》2004,104(9):2752-2760
Emerging evidence to support the use of endothelial progenitor cells (EPCs) for angiogenic therapies or as biomarkers to assess cardiovascular disease risk and progression is compelling. However, there is no uniform definition of an EPC, which makes interpretation of these studies difficult. Although hallmarks of stem and progenitor cells are their ability to proliferate and to give rise to functional progeny, EPCs are primarily defined by the expression of cell-surface antigens. Here, using adult peripheral and umbilical cord blood, we describe an approach that identifies a novel hierarchy of EPCs based on their clonogenic and proliferative potential, analogous to the hematopoietic cell system. In fact, some EPCs form replatable colonies when deposited at the single-cell level. Using this approach, we also identify a previously unrecognized population of EPCs in cord blood that can achieve at least 100 population doublings, replate into at least secondary and tertiary colonies, and retain high levels of telomerase activity. Thus, these studies describe a clonogenic method to define a hierarchy of EPCs based on their proliferative potential, and they identify a unique population of high proliferative potential-endothelial colony-forming cells (HPP-ECFCs) in human umbilical cord blood. 相似文献
23.
24.
前列腺特异抗原研究进展与挑战(摘要) 总被引:1,自引:0,他引:1
前列腺特异抗原(PSA)发现四分之一世纪以来,已成为诊断前列腺癌最有价值的肿瘤标志物。前列腺癌在男性癌症发病中占首位。自从80年代中期第一代检测PSA的方法问世以来,前列腺癌的发病率有了显著改变。这部分归功于PSA检测的增加,从而使前列腺癌得到早期诊断,这有利于将癌症控制在发病早期,增加治愈的可能性。虽然PSA是一个有效的肿瘤标志物,并具有器官特异性,但其癌症特异性不高。PSA升高也可见于其他良性前列腺疾病,尤其当PSA浓度在4~10μg/L时。这个浓度范围被称为“诊断灰色区域”。对PSA分子结构的研究主要集中… 相似文献
25.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献
26.
27.
Porter DW; Yakushiji H; Nakabeppu Y; Sekiguchi M; Fivash MJ Jr; Kasprzak KS 《Carcinogenesis》1997,18(9):1785-1791
The toxicity of Ni(II), Co(II) and Cu(II) in animals, and that of Cd(II) in
cultured cells, has been associated with generation of the promutagenic
lesion 8-oxo-7,8-dihydroguanine (8-oxoguanine) in DNA, among other effects.
One possible source of this base may be 8-oxo-7,8-
dihydro-2'-deoxyguanosine-5'-triphosphate (8-oxo-dGTP), a product of
oxidative damage to the nucleotide pool, from which it is incorporated into
DNA. To promote such incorporation, the metals would have to inhibit
specific cellular 8-oxo-dGTPases that eliminate 8-oxo-dGTP from the
nucleotide pool. The present study was designed to test such inhibition in
vitro on 8-oxo-dGTPases from two different species, the human MTH1 protein
and Escherichia coli MutT protein. In the presence of Mg(II), the natural
activator of 8-oxo-dGTPases, all four metals were found to inhibit both
enzymes. For MTH1, the IC50 values (+/- SE; n = 3-4) were 17 +/- 2 microM
for Cu(II), 30 +/- 8 microM for Cd(II), 376 +/- 71 microM for Co(II) and
801 +/- 97 microM for Ni(II). For MutT, they were 60 +/- 6 microM for
Cd(II), 102 +/- 8 microM for Cu(II), 1461 +/- 96 microM for Ni(II) and 8788
+/- 1003 microM for Co(II). Thus, Cu(II) and Cd(II) emerged as much
stronger inhibitors than Ni(II) and Co(II), and MTH1 appeared to be
generally more sensitive to metal inhibition than MutT. Interestingly, in
the absence of Mg(II), the activity of the enzymes could be restored by
Co(II) to 73% of that with Mg(II) alone for MutT, and 34% for MTH1, the
other metals being much less or non-effective. The difference in
sensitivity to metal inhibition between the two enzymes may reflect the
differences in the amino acid ligands, especially the cysteine ligand,
outside their evolutionarily conserved Mg(II)-binding active sites, which
might indicate predominantly non-competitive or uncompetitive mechanism of
the inhibition. The overall results suggest that inhibition of 8-oxo-
dGTPases may be involved in the mechanisms of induction of the 8-
oxoguanine lesion in DNA by the metal ions studied, especially the non-
redox-active Cd(II) cation.
相似文献
28.
A search for children presenting with signs or symptoms of cardiac rhabdomyomas was made through members of the paediatric section of the British Cardiac Society in order to establish their birth incidence, presenting features, clinical course, and the frequency of a concurrent diagnosis of tuberous sclerosis. Fifteen children were identified and 12 had tuberous sclerosis (80%). Heart failure was the presentation in six, five of whom died; six presented because of a murmur and three because of arrhythmias. The prevalence of echocardiographic evidence of cardiac rhabdomyomas in a population of patients with tuberous sclerosis was established. Twenty individuals had echocardiography and eight had echodensities consistent with cardiac rhabdomyomas. It is concluded that the minimum birth incidence for children presenting because of the effects of cardiac rhabdomyomas is 1/326,000 and a minimum of 80% have tuberous sclerosis. In a population of patients with tuberous sclerosis a minimum of 60% under 18 years have cardiac rhabdomyomas. 相似文献
29.
To determine the outcome of congenital lung abnormalities, data were collected retrospectively between January 1991 and December 1996 on any foetus found to have a lung lesion on antenatal ultrasound. A total of 23 foetuses had lung lesions on antenatal ultrasound. In two foetuses the antenatal ultrasound showed bilateral enlarged "bright" echogenic lungs with evidence of hydrops. Both pregnancies were terminated and tracheal atresia was confirmed. In 15 foetuses the antenatal ultrasound appearance was of a unilateral "bright" echogenic lung. There was one case of bronchial atresia and two cases of congenital lobar emphysema, which all had surgery. In nine cases there was a reduction in the size of the lesion on serial antenatal ultrasounds and no lesion was detected after birth. In three cases a small lesion was present after birth on chest radiography. In six foetuses the antenatal ultrasound appearance was of unilateral cystic or mixed cystic and echogenic lung lesions. Two pregnancies were terminated; both had congenital cystic adenomatoid malformation. Four pregnancies were continued and three infants had surgery soon after birth and were confirmed to have had congenital cystic adenomatoid malformation. One infant has been managed conservatively. In conclusion, a definitive diagnosis cannot usually be made antenatally. A large lesion on initial scan does not necessarily predict a poor outcome. The natural history of small asymptomatic postnatal lesions is unknown and a long-term prospective study is needed to determine the outcome of these lesions. 相似文献
30.