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21.
22.
L Fraenkel RL Street V Towle JR O'Leary L Iannone PH Van Ness TR Fried 《Journal of the American Geriatrics Society》2012,60(8):1434-1441
23.
牛津膝置换是使用最广泛的膝关节单髁置换(UKR)。牛津膝在37年前开始应用,拥有一个全匹配的活动衬垫,因而磨损率非常低。牛津膝最主要的使用指征是膝关节前内侧骨关节炎,这种病人至少占所有需要行膝关节置换术患者的50%。由于这一系统的设计特点,传统UKR的反指征,如年龄、活动量、肥胖、髌股关节损害和软骨钙质沉着症等对于牛津膝均不是反指征。与全膝关节置换(TKR)相比,牛津膝提供更快的康复、更好的功能、更大的活动度和更好的术后满意度,发生并发症更少、程度更轻,病残率和死亡率更低。一个持续超过30年的研究显示在90%的病例中,牛津膝为患者终生提供了优或良的临床结果,且不需要翻修。在最近15年,牛津膝通过微创手术入路植入,涉及6000多例使用该入路牛津膝置换的9个研究报道显示,10年生存率约95%。在许多这样的研究中,医生们在拟行膝关节置换的患者中约50%使用了牛津单髁膝置换。 相似文献
24.
We have investigated the hormonal responsiveness of K562 cells using a serum-substituted in vitro clonogenic assay. Dexamethasone inhibited colony formation by the K562 cells, and the inhibitory effect could be reversed by progesterone (10(-6) M). Fluoxymesterone caused a prominent enhancement of K562 colony growth, whereas estriol had no effect. Stimulation by triiodothyronine was maximal at 10(-7) M, and the thyroid effect could be abrogated by the beta 2-adrenergic antagonist butoxamine in equimolar concentrations. Using standard tissue culture conditions, the beta-adrenergic agent isoproterenol, but not the alpha catecholamine phenylephrine, enhanced the proliferation of K562 cells. When K562 cells were grown under hormone-depleted conditions, they developed responsiveness to phenylephrine and were no longer stimulated by isoproterenol. DbcAMP and prostaglandins of the E series also caused K562 colony enhancement. Prostaglandin F2 alpha had no effect on cell proliferation. Insulin was an effective stimulant of colony formation of K562 cells, as were human growth hormone and ovine prolacin. Bovine growth hormone had no effect. Our results are consistent with the identificaiton of K562 as an erythroid line, and they indicate that K562 cells respond to endocrine hormones in a manner analogous to normal erythroid progenitors. 相似文献
25.
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
26.
27.
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
28.
Manisha Juthani-Mehta Mary Tinetti Eleanor Perrelli Virginia Towle Peter H Van Ness Vincent Quagliarello 《Infection control and hospital epidemiology》2008,29(5):446-449
We determined the interobserver variability in the assessment of clinical criteria for urinary tract infection (UTI) in nursing home residents. Pairs of nursing home staff caring for 30 residents were interviewed at the time UTI was suspected. At least one measure from each of 7 clinical criteria categories was reliably assessed by nursing home staff members. 相似文献
29.
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
30.
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.
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