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991.
BACKGROUND: The incidence of prostate cancer in black men is 50% to 70% higher than among age-matched white men. Black men have a twofold higher mortality rate and overall tend to have higher serum prostate-specific antigen (PSA) levels than white men. To determine whether racial differences exist in men whose prostate cancer was diagnosed based solely on an elevated serum PSA level, we compared clinical and pathologic features in black and white men undergoing radical prostatectomy (RP) for clinical stage T1c prostate cancer. METHODS: We used a prospectively collected database to identify all men undergoing RP for clinical T1c prostate cancer between July 1995 and October 2000. A total of 129 consecutive men (56 black men and 73 white men) were compared for age at diagnosis, serum PSA level, biopsy Gleason score, pathologic stage, RP specimen Gleason score, incidence of lymph node metastasis, and incidence of positive surgical margins. RESULTS: Statistically significant differences were not found by race in patients' ages, serum PSA levels, biopsy Gleason score, pathologic stage, incidence of lymph node metastases, or incidence of positive surgical margins. The RP specimen Gleason score was more heterogeneous in black men than white men (P=0.02). CONCLUSIONS: Racial differences in the incidence and mortality rate of prostate cancer are well known, but differences in the clinical and pathologic features between black and white men with prostate cancer identified solely based on an elevated serum PSA level with negative results on digital rectal examination (clinical stage T1c ) have been poorly studied. Our results suggest that men with clinical stage T1c prostate cancer have similar clinical and pathologic findings regardless of race. These results suggest that early-detection programs using serum PSA testing for prostate cancer in black men potentially can result in improvements in prostate cancer outcomes in this high-risk group.  相似文献   
992.
Siu SW  Lau KW  Tam PC  Shiu SY 《The Prostate》2002,52(2):106-122
BACKGROUND: Potential modulatory effects of melatonin on the proliferation of androgen-sensitive LNCaP and androgen-insensitive PC-3 and DU 145 prostate cancer cells were reported recently. In this study, we investigated the effects of combined melatonin and castration on LNCaP tumor growth in vivo, the interactions between melatonin and epidermal growth factor (EGF) on LNCaP cell proliferation, and melatonin actions on the proliferation of PC-3 and DU 145 cells. METHODS: Tumor development and growth in castrated nude mice inoculated with LNCaP cells or in intact animals inoculated with DU 145 cells, with or without daily melatonin treatment, were monitored by observation and caliper measurement. MT(1) receptor expression in native or transfected prostate cancer cell lines was examined by immunocytochemistry or 2-[(125)I]iodomelatonin binding. Cyclin D1 expression in LNCaP cells was assessed by Western blotting, and cell proliferation was measured by thymidine incorporation and/or cell count. RESULTS: Melatonin treatment was associated with further decreases in LNCaP tumor incidence and growth rate in castrated nude mice. Melatonin and 2-iodomelatonin (a melatonin receptor agonist) attenuated EGF-stimulated increases in LNCaP cell proliferation and cyclin D1 levels. Melatonin had no effect on the proliferation or growth of MT(1) receptor-expressing DU 145 cells, and of PC-3 cells in which MT(1) receptor protein was undetectable. The proliferation of transfected PC-3 cells expressing MT(1) receptor was unaffected by 2-iodomelatonin. CONCLUSION: Together with previous data, the present results indicate synergistic action of melatonin and castration in inhibiting the growth of androgen-sensitive LNCaP tumor. Androgen-sensitive prostate cancer cell proliferation may be modulated by opposite changes in cyclin D1 levels induced by activated MT(1) and EGF receptors. In androgen-insensitive prostate cancer cells, MT(1) receptor-mediated signal transduction may become defective not only through changes in membrane receptor protein expression and/or functions, but also by means of alterations in downstream postreceptor signaling events.  相似文献   
993.
Acne treatment with a 1,450 nm wavelength laser and cryogen spray cooling   总被引:8,自引:0,他引:8  
BACKGROUND AND OBJECTIVES: A laser with a wavelength in the mid-IR range targeting the depth in skin where sebaceous glands are located in combination with cryogen spray cooling was evaluated for treatment of acne. In this non-ablative treatment, the laser energy heats the dermal volume encompassing sebaceous glands whereas the cold cryogen spray preserves the epidermis from thermal damage. STUDY DESIGN/MATERIALS AND METHODS: Monte Carlo simulations and heat transfer calculations were performed to optimize the heating and cooling parameters. A variety of heating and cooling parameters were tested in an in vivo rabbit ear study to evaluate the histological effect of the device on sebaceous glands and skin. Similar experiments were performed on ex vivo human skin. A clinical study for the treatment of acne on backs of human males was also conducted. RESULTS: Monte Carlo simulations and heat transfer calculations resulted in a thermal damage profile that showed epidermal preservation and peak damage in the upper dermis where sebaceous glands are located. Ex vivo human skin histology confirmed the damage profile qualitatively. In vivo rabbit ear histology studies indicated short-term thermal alteration of sebaceous glands with epidermal preservation. In the human clinical study on the back, a statistically significant reduction in lesion count on the treated side compared to the control side was seen (p < 0.001). Side effects were transient and few. CONCLUSIONS: The studies reported here demonstrate the feasibility of treating acne using a photothermal approach with a mid-IR laser and cryogen cooling.  相似文献   
994.
This study examines the responsiveness of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Short Form-36 (SF-36) in patients undergoing total hip arthroplasty. Eighty-nine patients completed the WOMAC and SF-36 preoperatively and postoperatively. Standardized response means (SRMs) and effect sizes (ES) were used to measure responsiveness. Mean follow-up was 17 months. The SRMs for the WOMAC ranged from -0.93 to -1.49, and the ES ranged from -1.02 to -1.53. The SRMs for the SF-36 ranged from 0.22 to 1.64, and the ES ranged from 0.20 to 1.97. The highest values occurred with the physical functioning, bodily pain, and Physical Component Summary Scales. This study demonstrates a similar level of responsiveness of the WOMAC and several components of the SF-36. This suggests that the isolated use of the SF-36 may be adequate to monitor outcomes after total hip arthroplasty. There may still be a role for the WOMAC when comparing outcomes of specific designs or techniques of total hip arthroplasty.  相似文献   
995.
BACKGROUND AND OBJECTIVES: Cryogen spray cooling with tetrafluoroethane (R134a) has been used to enhance epidermal protection during dermatologic laser surgery. However, R134a has a very high global warming potential (GWP = 1300). Our objective was to evaluate the cooling effectiveness of an alternative cryogen with a much lower GWP, namely liquid carbon dioxide (CO(2), GWP = 1). STUDY DESIGN/MATERIALS AND METHODS: A thin-film thermocouple deposited on an epoxy skin phantom was used to measure surface temperature (T(s)) variations induced by R134a or CO(2) sprays. The temperature distribution in the skin phantom was estimated using T(s) and Duhamel's method. Impact pressure and noise level of both cryogen sprays were measured with a dynamic sensor and sound meter, respectively. Consumption of both cryogens was also evaluated. RESULTS: For R134a sprays, T(s) was kept almost constant after 15 milliseconds. For CO(2) sprays, T(s) decreased continuously during the entire spurt of 50 milliseconds. The minimum T(s) induced by the CO(2) sprays was lower than that induced by R134a when the spurt duration was longer than 35 milliseconds. Numerical simulation shows that CO(2) sprays were able to induce very similar temperature reductions in the skin phantom as compared to R134a sprays when the spurt duration and delay time were selected appropriately. R134a sprays induced an impact pressure of 3.6 kPa, as compared to 43.1 kPa for CO(2) sprays. The maximum noise level for R134a sprays was 109 dBA as compared to 135 dBA for the CO(2) sprays. The R134a consumption for a 50 milliseconds spurt is 67 mg as compared to 225 mg for a CO(2) spurt of the same duration. CONCLUSIONS: CO(2) sprays are expected to have similar skin cooling efficacy as R134a sprays. Although the CO(2) consumption is higher than R134a, its contribution to global warming is still much less than R134a. The effects of varying spurt durations on in vivo human skin and the impact on cutaneous blood flow require further investigation.  相似文献   
996.
目的探讨脊髓纵裂分型治疗的疗效。方法对1978年5月至2006年11月收洽的有完整资料的121例单管型及双管型脊髓纵裂患者的病历资料进行回顾性分析,并通过临床神经功能评分及胫后神经皮层体感诱发电位(FTNCSEP)P40波峰监测,评价其手术及非手术治疗的疗效。结果所有患者均得到随访,随访时间6个月~15年,平均2年6个月。96例双管型患者中手术治疗86例,术后观察和随访发现24例痊愈、22例有明显改善、28例有一定改善、12例无明确效果,临床神经功能评分及PTNCSEP术后有明显改变,尤其是以疼痛为主诉的患者恢复最为明显,手术总有效率为86%;10例双管型患者未行手术治疗,随访发现临床症状无明显改善且有加重趋势。单管型患者25例,手术治疗16例,术前、术后临床神经功能评分及胛NCSEP无明显变化;未手术治疗的9例,随访时上述指标亦无明显变化。结论双管型脊髓纵裂患者脊髓损害重且呈进行性加重,精细的手术治疗可以使大多数患者症状得到缓解,终止神经进行性损伤,确诊后应尽早手术。单管型脊髓纵裂患者脊髓损害轻,无须手术探查。  相似文献   
997.
Few studies have examined outcomes of laparoscopic and open sigmoid colectomy performed at US academic centers. Using ICD-9 diagnosis and procedural codes, data was obtained from the University HealthSystem Consortium (UHC) Clinical Database of 10,603 patients who underwent laparoscopic or open sigmoid colectomy for benign and malignant disease between 2003–2006. A total of 1,092 patients (10.3%) underwent laparoscopic sigmoid colectomy. Laparoscopic sigmoid colectomy was associated with a significantly shorter length of stay (5.4 vs 7.4 days), lower overall complication rate (19.7 vs 26.0%), lower 30-day readmission rate (3.4 vs 4.6), and a lower hospital cost ($13,814 vs $15,626). When a subset analysis of malignant and benign groups was performed, a significantly shorter length of stay in both the malignant laparoscopic group (6.4 ± 6.4 vs 7.8 ± 6.6 days) and in the benign laparoscopic groups (5.1 ± 3.5 vs 7.2 ± 7.6) exists. A lower wound complication rate (2.1 vs 5.5%, malignant and 4.0 vs 6.1, benign) is also evident. Laparoscopic sigmoid colectomy was associated with a shorter length of stay, less complications, and a lower 30-day readmission rate. The shorter length of stay and wound infection rate maintain significance when comparing laparoscopic vs open sigmoid resections for malignant and benign disease. Presented at the 48th annual meeting of the Society for Surgery of the Alimentary Tract at Digestive Disease Weak, Washington, DC, May 21st 2007. The information contained in this article was based on the Clinical Data Base provided by the University HealthSystem Consortium.  相似文献   
998.
To report the results obtained with the transobturator sub-urethral tape (TOT) for the surgical treatment of stress urinary incontinence (SUI) after 1 year follow-up. Ninety-three patients diagnosed with SUI or mixed urinary incontinence (MUI) underwent a TOT procedure associated to prolapse surgery, if necessary. Pre-operative quality of life (QoL) was assessed with the Urogenital Distress Inventory Short Form (UDI-6)/Incontinence Impact Questionnaire Short Form (IIQ-7) questionnaires. Surgical and early complications were monitored. A stress test and an urodynamic test if urge incontinence de novo appeared were performed at 1 year follow-up. UDI-6/IIQ-7 questionnaires and SUI symptoms were recorded. Patients’ characteristics, pre-operative quality of life and urodynamic evaluation were similar in the TOT and in the pelvic floor surgery group. From the sample, 15% had post-operative retention and 10% had vaginal erosion. The global rate of objective cure was 97% in both groups. The scores of the QoL questionnaires were worse by 9% and 10% with the procedure, respectively. Patients with urodynamic (MUI) or persistence of SUI symptoms (10%) did not reach a significant improvement, although patients with urge incontinence de novo (10%) did. The TOT procedure is safe and effective. Results showed that the association to pelvic floor surgical techniques did not diminish 1 year later. The stress test outcome assessment can overestimate the results, compared to the QoL assessment. In our report, the MUI did not improve with this surgical approach. Our results highlight the necessary employment of both the objective testing and the patient’s opinion of her symptoms during daily life.  相似文献   
999.
1000.
BACKGROUND: There are few studies of the pharmacokinetics of vancomycin and gentamicin in peritoneal dialysis (PD) patients and the influence of antibiotic concentrations on treatment outcome. Concerns about resistance to ceftazidime and potential of aminoglycoside toxicity make the choice of empiric antibiotic difficult. METHODS: We retrospectively collected data from 613 patients on PD between 1 June 2002 and 31 December 2005. During this time, we adopted a protocol that minimized aminoglycoside exposure to patients with residual renal function and carefully monitored serum antibiotic concentrations. RESULTS: There were no statistical differences in mean day-5 vancomycin concentrations for continuous ambulatory peritoneal dialysis (CAPD) vs automated peritoneal dialysis (APD) and for anuric vs not-anuric patients. However, low levels (<12 mg/l) were recorded for 12.8% CAPD and 15% APD patients. These remained low at day 10 in 16% patients (25% if not anuric) despite incremental dosing. Vancomycin concentration did not predict cure or relapse of Gram-positive or culture-negative peritonitis. Gentamicin concentration (>2 mg/l in >50% patients) did not predict outcome of Gram-negative and culture-negative peritonitis. Moreover, cure rates were the same irrespective of whether gentamicin was continued for 14 days or was switched to ceftazidime after 5 days. CONCLUSION: We have confirmed that the International Society for Peritoneal Dialysis (ISPD) dosing guideline for vancomycin in CAPD and APD patients produces adequate serum concentrations of the antibiotics in the vast majority. However, large incremental dosing of vancomycin is needed if day-5 levels are low; especially for not-anuric patients. Whilst evidence of gentamicin toxicity in PD remains controversial, ISPD dosing regimen resulted in high levels for >50% patients. High gentamicin concentrations did not correlate with treatment success, but switching gentamicin to ceftazidime at day 5 appeared safe and limited aminoglycoside exposure. Increasing vancomycin and gentamicin concentrations do not appear to improve cure rates and alternative strategies (such as combination treatment) should be considered for future research.  相似文献   
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