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31.
Proton MR spectroscopy of the prostate 总被引:5,自引:0,他引:5
PURPOSE: To summarize current technical and biochemical aspects and clinical applications of proton magnetic resonance spectroscopy (MRS) of the human prostate in vivo. MATERIAL AND METHODS: Pertinent radiological and biochemical literature was searched and retrieved via electronic media (medline, pubmed. Basic concepts of MRS of the prostate and its clinical applications were extracted. RESULTS: Clinical MRS is usually based on point resolved spectroscopy (PRESS) or spin echo (SE) sequences, along with outer volume suppression of signals from outside of the prostate. MRS of the prostate detects indicator lines of citrate, choline, and creatine. While healthy prostate tissue demonstrates high levels of citrate and low levels of choline that marks cell wall turnover, prostate cancer utilizes citrate for energy metabolism and shows high levels of choline. The ratio of (choline+creatine)/citrate distinguishes between healthy tissue and prostate cancer. Particularly when combined with magnetic resonance (MR) imaging, three-dimensional MRS imaging (3D-CSI, or 3D-MRSI) detects and localizes prostate cancer in the entire prostate with high sensitivity and specificity. Combined MR imaging and 3D-MRSI exceed the sensitivity and specificity of sextant biopsy of the prostate. When MRS and MR imaging agree on prostate cancer presence, the positive predictive value is about 80-90%. Distinction between healthy tissue and prostate cancer principally is maintained after various therapeutic treatments, including hormone ablation therapy, radiation therapy, and cryotherapy of the prostate. CONCLUSIONS: Since it is non-invasive, reliable, radiation-free, and essentially repeatable, combined MR imaging and 3D-MRSI of the prostate lends itself to the planning of biopsy and therapy, and to post-therapeutic follow-up. For broad clinical acceptance, it will be necessary to facilitate MRS examinations and their evaluation and make MRS available to a wider range of institutions. 相似文献
32.
Luis A. Kluth Malte Rieken Evanguelos Xylinas Matthew Kent Michael Rink Morgan Rouprêt Nasim Sharifi Asha Jamzadeh Wassim Kassouf Dharam Kaushik Stephen A. Boorjian Florian Roghmann Joachim Noldus Alexandra Masson-Lecomte Dimitri Vordos Masaomi Ikeda Kazumasa Matsumoto Masayuki Hagiwara Eiji Kikuchi Yves Fradet Jonathan Izawa Ricardo Rendon Adrian Fairey Yair Lotan Alexander Bachmann Marc Zerbib Margit Fisch Douglas S. Scherr Andrew Vickers Shahrokh F. Shariat 《European urology》2014
Background
The impact of gender on the staging and prognosis of urothelial carcinoma of the bladder (UCB) is insufficiently understood.Objective
To assess gender-specific differences in pathologic factors and survival of UCB patients treated with radical cystectomy (RC).Design, setting, and participants
Data from 8102 patients treated with RC (6497 men [80%] and 1605 women [20%]) for UCB between 1971 and 2012 were analyzed.Outcome measurements and statistical analysis
Multivariable competing-risk regression analyses were performed to evaluate the relationship of gender on disease recurrence (DR) and cancer-specific mortality (CSM). We also tested the interaction of gender and tumor stage, nodal status, and lymphovascular invasion (LVI).Results and limitations
Female patients were older at the time of RC (p = 0.033) and had higher rates of pathologic stage T3/T4 disease (p < 0.001). In univariable, but not in multivariable analysis, female gender was associated with a higher risk of DR (p = 0.022 and p = 0.11, respectively). Female gender was an independent predictor for CSM (p = 0.004). We did not find a significant interaction between gender and stage, nodal metastasis, or LVI (all p values >0.05).Conclusions
We found female gender to be associated with a higher risk of CSM following RC. However, these findings do not appear to be explained by gender differences in pathologic stage, nodal status, or LVI. This gender disparity may be due to differences in care and/or the biology of UCB. 相似文献33.
Niklas Darin Mårten Kyllerman Anna-Lena Hård Claes Nordborg Jan-Eric Månsson 《European journal of paediatric neurology》2009,13(6):553-555
Galactosialidosis (MIM 256540) is an autosomal recessive lysosomal storage disease caused by a defect of the protective protein/cathepsin A. Increased amounts of urinary sialic acid-rich oligosaccharides are considered to be an essential diagnostic marker of the disease. We here report a patient with atypical clinical features who consistently has excreted normal amounts of sialyloligosaccharides in the urine. The boy started to have attacks of neuropathic pain associated with hyperesthesia around 1½ years of age. From 4 years of age when his vision was first tested, the patient developed progressive visual loss and at the age of 10 years, macular cherry-red spots were found. At this age, he also had a mild learning disability and clinical examination showed mild facial coarsening, increased lumbar lordosis and pyramidal signs in the legs. In conclusion, the clinical and laboratory features of this patient show that galactosialidosis may be considered in patients even in the absence of oligosacchariduria and that galactosialidosis should be regarded as a differential diagnosis in patients with neuropathic pain. 相似文献
34.
Patrice Anderberg RN MScEd Anna-Lena Berglund PhD RNT MScEd 《International journal of nursing practice》2010,16(1):64-68
Anderberg P, Berglund A-L. International Journal of Nursing Practice 2010; 16 : 64–68
Elderly persons' experiences of striving to receive care on their own terms in nursing homes
Elderly persons' participation in and decisions about their own care need more attention. The aim of this study was to gain a deeper understanding of elderly persons' experiences of care and help, and how their lives change in nursing homes. Fifteen elderly persons living in four nursing homes were interviewed about their experiences of needing care and help in their daily life. The interviews were analysed using van Manen's phenomenological approach. Elderly persons' experiences of care and help were described as: a balance between sorrow and relief, a struggle to maintain control and connectedness, managing to live in the present and yet worrying about the future, and an attempt to hide one's vulnerability in order to be accepted and create an inner calm in an exposed situation. In conclusion, important issues were raised concerning elderly persons' perspectives on care and help in daily life in nursing homes. 相似文献
Elderly persons' experiences of striving to receive care on their own terms in nursing homes
Elderly persons' participation in and decisions about their own care need more attention. The aim of this study was to gain a deeper understanding of elderly persons' experiences of care and help, and how their lives change in nursing homes. Fifteen elderly persons living in four nursing homes were interviewed about their experiences of needing care and help in their daily life. The interviews were analysed using van Manen's phenomenological approach. Elderly persons' experiences of care and help were described as: a balance between sorrow and relief, a struggle to maintain control and connectedness, managing to live in the present and yet worrying about the future, and an attempt to hide one's vulnerability in order to be accepted and create an inner calm in an exposed situation. In conclusion, important issues were raised concerning elderly persons' perspectives on care and help in daily life in nursing homes. 相似文献
35.
Alzheimer disease in the US population: prevalence estimates using the 2000 census 总被引:25,自引:0,他引:25
CONTEXT: Current and future estimates of Alzheimer disease (AD) are essential for public health planning. OBJECTIVE: To provide prevalence estimates of AD for the US population from 2000 through 2050. DESIGN: Alzheimer disease incidence estimates from a population-based, biracial, urban study, using a stratified random sampling design, were converted to prevalence estimates and applied to US Census Bureau estimates of US population growth. SETTING: A geographically defined community of 3 adjacent neighborhoods in Chicago, Ill, applied to the US population. PARTICIPANTS: Alzheimer disease incidence was measured in 3838 persons free of AD at baseline; 835 persons were evaluated for disease incidence.Main Outcome Measure Current and future estimates of prevalence of clinically diagnosed AD in the US population. RESULTS: In 2000, there were 4.5 million persons with AD in the US population. By 2050, this number will increase by almost 3-fold, to 13.2 million. Owing to the rapid growth of the oldest age groups of the US population, the number who are 85 years and older will more than quadruple to 8.0 million. The number who are 75 to 84 years old will double to 4.8 million, while the number who are 65 to 74 years old will remain fairly constant at 0.3 to 0.5 million. CONCLUSION: The number of persons with AD in the US population will continue to increase unless new discoveries facilitate prevention of the disease. 相似文献
36.
Talaat M el-Oun S Kandeel A Abu-Rabei W Bodenschatz C Lohiniva AL Hallaj Z Mahoney FJ 《Tropical medicine & international health : TM & IH》2003,8(3):234-241
OBJECTIVE: To describe the extent and characteristics of injection use and injection providers in Egypt, given that unsafe injections are associated with blood-borne pathogen transmission. METHODS: Household surveys of a population-based sample of residents in the Nile Delta and in Upper Egypt; focus group discussions and in-depth interviews with community target groups, formal and informal medical providers. RESULTS: Of 4197 persons interviewed, 26.2% reported receiving an injection in the past 3 months. Of these, 77% reported it was for therapeutic indications. The age-sex specific prevalence of injections was highest among children 0-2 years of age and among older adults. Women were more likely to report having an injection than men, particularly at the age above 20 years. Overall, respondents reported receiving on average 4.2 injections per year, indicating that up to 281 million injections are provided per year in Egypt. Injection administrators were public and private sector physicians, pharmacists, barbers, doctor assistants, housekeepers, relatives and friends. Injection prescribers were mostly private and public sector physicians. Of the 1101 respondents who received an injection in the past 3 months, 92 (8.4%) reported that the provider did not use a syringe taken from a closed sealed packet. CONCLUSION: The frequency of therapeutic injection use is high in Egypt and may contribute to blood-borne pathogen transmission. The Ministry of Health and Population (MOHP) is developing interventions targeted towards promotion of injection safety and reduction of injection overuse on community basis as part of a comprehensive strategy to prevent blood-borne pathogen transmission in Egypt. 相似文献
37.
Electrophysiological actions of phenytoin on N-methyl-D-aspartate receptor-mediated responses in rat hippocampus in vitro.
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A. J. Laffling P. Scherr J. G. McGivern L. Patmore R. D. Sheridan 《British journal of pharmacology》1995,115(1):67-72
1. [3H]-bradykinin was used to characterize the bradykinin receptors associated with canine cultured tracheal smooth muscle cells (TSMCs). Receptor binding assay showed that TSMCs had specific, saturable, high-affinity binding sites for [3H]-bradykinin. 2. The specific [3H]-bradykinin binding increased linearly with increasing cell concentrations. The equilibrium for association of [3H]-bradykinin with the bradykinin receptors was attained within 2 h at 4 degrees C and 1 h at room temperature, respectively. 3. Analysis of binding isotherms yielded an apparent equilibrium dissociation constant (KD) of 2.5 +/- 0.3 nM and a maximum receptor density (Bmax) of 25.1 +/- 0.3 fmol mg-1 protein. The Hill coefficient for [3H]-bradykinin binding was 1.00 +/- 0.02. The association (K1) and dissociation (K-1) rate constants were (8.67 +/- 2.60) x 10(6) M-1 min-1 and 0.024 +/- 0.005 min-1, respectively. KD, calculated from the ratio of K-1 and K1 was 2.8 +/- 0.5 nM, a value close to that of KD calculated from Scatchard plots of binding isotherms. 4. The B1 receptor selective agonist, (des-Arg9-bradykinin, 0.1 nM-10 microM) and antagonist ([Leu8, des-Arg9]-bradykinin, 0.1 nM-10 microM) did not did not inhibit the [3H]-bradykinin binding to TSMCs, which excludes the presence of B1 receptors in canine TSMCs.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
38.
Mattias Lorentzon Anna-Lena Eriksson Dan Mellstr?m Claes Ohlsson 《Journal of bone and mineral research》2004,19(12):2005-2011
The associations between the functional val158met polymorphism of the estrogen-degrading COMT enzyme and skeletal properties in young men were investigated. BMD was associated with COMT genotype. INTRODUCTION: Peak BMD is an important predictor of future risk of osteoporosis, and it is to a large extent determined by genetic factors. Estrogens are involved in the accretion of bone mass during puberty. Catechol-O-methyltransferase (COMT) is involved in the degradation of estrogens. There is a functional polymorphism in the COMT gene (val158met), resulting in a 60-75% difference in enzyme activity between the val (high activity [H]) and met (low activity [L]) variants. The aim of this cross-sectional study was to investigate the associations between this polymorphism and peak BMD in young men. MATERIALS AND METHODS: A total of 458 healthy men (mean age, 19 +/- 0.6 years) were genotyped and classified as COMT(LL), COMT(HL), or COMT(HH). Areal BMD (aBMD) was measured by DXA. Cortical and trabecular volumetric BMD (vBMD) were measured by pQCT. The associations between COMT genotype and skeletal phenotypes were determined. RESULTS AND CONCLUSIONS: Regression models using physical activity, height, weight, age, and COMT genotype as covariates showed that COMT genotype was an independent predictor of aBMD in the total body and in all femur locations investigated, but not in the spine. The values for COMT(HL) and COMT(HH) were very similar, and therefore, they were pooled into one group. aBMD at Ward's triangle, trochanter, and total femur were 4.9%, 4.5%, and 3.7% lower, respectively, in the COMT(LL) than in the COMT(HL/HH) group (p < 0.01). pQCT analyses showed that COMT genotype was an independent predictor of trabecular vBMD of the tibia, radius, and fibula. Trabecular vBMD of the radius and fibula in COMT(LL) was 5.3% and 7.4% lower, respectively, than that of the combined COMT(HL/HH) group. COMT genotype was associated with cortical vBMD but not with cortical cross-sectional area in the tibia. These findings show that the COMT polymorphism is associated with BMD in young adult men. 相似文献
39.
Boorjian S Scherr DS Mongan NP Zhuang Y Nanus DM Gudas LJ 《International journal of oncology》2005,26(4):1041-1048
Retinoids, which include vitamin A (retinol) and its derivatives, have previously been investigated as potential chemopreventive and chemotherapeutic agents in bladder cancer. We examined mRNA expression of the retinoid receptors RARalpha, RARbeta2, RARgamma and RXRalpha, as well as two putative RARbeta2 target genes, DAB2 and Midkine, in normal and malignant bladder tissue specimens from human patients. We evaluated 24 normal and malignant bladder specimens for retinoid receptor, DAB2 and Midkine mRNA expression using RT-PCR. We also examined the effects of retinoic acid and retinol on the expression of these genes in five human bladder cancer cell lines. Expression of RARalpha, RARbeta2, RARgamma and RXRalpha mRNA was detected in all of the non-neoplastic patient bladder specimens. RARbeta2 mRNA expression was undetectable in 7/13 tumors, RARalpha in 3/13, RARgamma in 1/13 and RXRalpha in 2/13. DAB2 mRNA was expressed in all non-neoplastic and all tumor specimens, while Midkine mRNA was detected in 8/11 non-neoplastic specimens versus 11/13 tumors. Two of the five bladder cancer cell lines expressed RARbeta2 independent of retinoid exposure; in three cell lines RARbeta2 expression was induced by retinoids. RARalpha, RARgamma and RXRalpha mRNA expression was detected in 5/5 cell lines, independent of retinoid exposure. We found a reduction in retinoid receptor mRNA expression, particularly for RARbeta2, in human bladder cancer specimens. We also demonstrated induction of RARbeta2 mRNA expression in some of the retinoid-treated bladder cancer cell lines. We suggest that restoration of RARbeta2 expression may be a reasonable biomarker for developing bladder cancer preventive and/or therapeutic drugs. 相似文献
40.
PURPOSE: To assess the psychosocial consequences of traffic accidents, and to evaluate the effect of an intervention programme to reduce the occurrence and extent of psychosocial residual states. MATERIAL AND METHODS: A telephone interview was conducted with 314 individuals, 1(1/2)-2 years after the accident in 1994-1995. The effect of the intervention programme was studied for inpatients, 68 in the study group, and 89 in the control group. The structured follow-up form included the Impact of Event Scale (IES). RESULTS: Half of those injured had residual physical complaints with negative effects on their work- and economic-situation. An influence on housing or the need for practical assistance was reported by 1-7%. Mental effects were reported by 4/5. IES demonstrated that 1/5 suffered a high degree of intrusion, and this occurred twice as often among females as among males. Situational anxiety occurred more often in the intervention group than in the control group, p=0.02. More individuals in the intervention group than in the control group were satisfied with the medical certificate to the insurance company, p=0.058. CONCLUSIONS: Females were afflicted by mental effects considerably more than males. The intervention programme did not appear to reduce the psychosocial sequelae. The methods within this area need to be further developed. 相似文献