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951.
Yam J  Kreuter M  Drewe J 《Planta medica》2008,74(1):33-38
Despite the high prevalence of prostate cancer (PC) in the Western world, there is a dearth of effective medication. Since the androgen-signalling pathway is very much involved in PC growth and development, we investigated the potential of Piper cubeba L. extract, P9605, in targeting multiple events simultaneously within this pathway. This may be more effective compared to an antiandrogen monotherapy. Our results indicated that P9605 inhibited proliferation in androgen-dependent LNCaP human prostate cancer cells by reducing DNA synthesis and inducing apoptosis. This antigrowth effect was less pronounced in androgen-independent PC-3 prostate cancer cell lines. P9605 potently inhibited 5 alpha-reductase II activity, which is responsible for converting testosterone to its active form, dihydrotestosterone (DHT), in the prostate. It also acted as an antagonist at recombinant wild-type androgen receptors (AR). P9605 suppressed cell growth and prostate-specific antigen (PSA) secretion stimulated by physiological concentrations of DHT in LNCaP cells. Interestingly, it down-regulated AR levels. In conclusion, our findings suggest that P9605 may potentially retard the growth of androgen-dependent PC via several mechanisms.  相似文献   
952.
953.
954.

Objective

A shared decision-making approach is suggested for multiple sclerosis (MS) patients. To properly evaluate benefits and risks of different treatment options accordingly, MS patients require sufficient numeracy – the ability to understand quantitative information. It is unknown whether MS affects numeracy. Therefore, we investigated whether patients’ numeracy was impaired compared to a probabilistic national sample.

Methods

As part of the larger prospective, observational, multicenter study PERCEPT, we assessed numeracy for a clinical study sample of German MS patients (N = 725) with a standard test and compared them to a German probabilistic sample (N = 1001), controlling for age, sex, and education. Within patients, we assessed whether disease variables (disease duration, disability, annual relapse rate, cognitive impairment) predicted numeracy beyond these demographics.

Results

MS patients showed a comparable level of numeracy as the probabilistic national sample (68.9% vs. 68.5% correct answers, P = 0.831). In both samples, numeracy was higher for men and the highly educated. Disease variables did not predict numeracy beyond demographics within patients, and predictability was generally low.

Conclusion

This sample of MS patients understood quantitative information on the same level as the general population.

Practice implications

There is no reason to withhold quantitative information from MS patients.  相似文献   
955.
956.

Purpose

We aimed to determine if family history (FH) of prostate cancer (PC) influenced cancer control after radical prostatectomy (RP).

Methods

Patients were evaluated in a prospectively-collected PC family database: The focus was on hereditary prostate cancer (HPC) defined by Johns Hopkins criteria and sporadic prostate cancer (SPC), rigorously defined by absence of prostate cancer in ≥ 2 brothers aged ≥ 60 years. Additionally, patients with first-degree (FPC) and non-first-degree PC (non-FPC) were assessed. Endpoints were biochemical recurrence-free survival (BRFS) and prostate cancer-specific survival (CSS). Finally, clinico-pathological characteristics were compared and multiple proportional hazards regression was used to identify prognostic factors.

Results

In total 11,654 patients were included (807 HPC, 2251 FPC, 8072 non-FPC and 524 SPC). Familial imposition (HPC/FPC) was associated with a younger age at diagnosis. Thus, HPC patients were diagnosed 2.9 years earlier than SPC patients with more locally advanced tumors (≥ pT3). With a median follow up of 6.2 years (range 0–31.5) BRFS was significantly different when stratified by FH. In pairwise analyses BRFS differed significantly for HPC compared to SPC (HR = 1.27). Consecutively FH was identified as prognostic factor for BRFS (p = 0.021) together with age, PSA, pathologic characteristics and adjuvant androgen deprivation. Analyses of CSS did not show a difference.

Conclusion

Patients with FH of PC are likely to be diagnosed earlier and present a higher proportion of locally advanced disease. In addition, men with FH are at higher risk of biochemical recurrence after surgery but reveal similar outcomes regarding prostate cancer-specific survival.
  相似文献   
957.

Purpose

Objective determination of the orbital volume is important in the diagnostic process and in evaluating the efficacy of medical and/or surgical treatment of orbital diseases. Tools designed to measure orbital volume with computed tomography (CT) often cannot be used with cone beam CT (CBCT) because of inferior tissue representation, although CBCT has the benefit of greater availability and lower patient radiation exposure. Therefore, a model-based segmentation technique is presented as a new method for measuring orbital volume and compared to alternative techniques.

Methods

Both eyes from thirty subjects with no known orbital pathology who had undergone CBCT as a part of routine care were evaluated (\(n = 60\) eyes). Orbital volume was measured with manual, atlas-based, and model-based segmentation methods. Volume measurements, volume determination time, and usability were compared between the three methods. Differences in means were tested for statistical significance using two-tailed Student’s t tests.

Results

Neither atlas-based \((26.63 \pm 3.15\,\hbox {mm}^{3})\) nor model-based \((26.87 \pm 2.99\,\hbox {mm}^{3})\) measurements were significantly different from manual volume measurements \((26.65 \pm 4.0\,\hbox {mm}^{3})\). However, the time required to determine orbital volume was significantly longer for manual measurements (\(10.24 \pm 1.21\) min) than for atlas-based (\(6.96 \pm 2.62\) min, \(p < 0.001\)) or model-based (\(5.73 \pm 1.12\) min, \(p < 0.001\)) measurements.

Conclusion

All three orbital volume measurement methods examined can accurately measure orbital volume, although atlas-based and model-based methods seem to be more user-friendly and less time-consuming. The new model-based technique achieves fully automated segmentation results, whereas all atlas-based segmentations at least required manipulations to the anterior closing. Additionally, model-based segmentation can provide reliable orbital volume measurements when CT image quality is poor.
  相似文献   
958.
A novel method of spontaneous generation of new adipose tissue from an existing fat flap is described. A defined volume of fat flap based on the superficial inferior epigastric vascular pedicle in the rat was elevated and inset into a hollow plastic chamber implanted subcutaneously in the groin of the rat. The chamber walls were either perforated or solid and the chambers either contained poly(D,L-lactic-co-glycolic acid) (PLGA) sponge matrix or not. The contents were analyzed after being in situ for 6 weeks. The total volume of the flap tissue in all groups except the control groups, where the flap was not inserted into the chambers, increased significantly, especially in the perforated chambers (0.08 +/- 0.007 mL baseline compared to 1.2 +/- 0.08 mL in the intact ones). Volume analysis of individual component tissues within the flaps revealed that the adipocyte volume increased and was at a maximum in the chambers without PLGA, where it expanded from 0.04 +/- 0.003 mL at insertion to 0.5 +/- 0.08 mL (1250% increase) in the perforated chambers and to 0.16 +/- 0.03 mL (400% increase) in the intact chambers. Addition of PLGA scaffolds resulted in less fat growth. Histomorphometric analysis rather than simple hypertrophy documented an increased number of adipocytes. The new tissue was highly vascularized and no fat necrosis or atypical changes were observed.  相似文献   
959.
PURPOSE: The aim of this study was to evaluate the effect of 2 surface conditioning methods and 2 luting-gap sizes on the retention and durability of zirconia ceramic copings bonded to titanium abutments. MATERIALS AND METHODS: Zirconia ceramic copings (Camlog Biotechnologies, Winsheim, Germany) with a luting-gap size of either 30 microm or 60 microm were bonded to titanium abutments (Camlog Biotechnologies) using the composite resin cement Panavia F (Kuraray, Osaka, Japan). The bonding surfaces of the zirconia ceramic copings were either (a) pretreated with airborne particle abrasion and cleaned with alcohol or (b) just cleaned with alcohol, whereas the bonding surfaces of all titanium abutments had been abraded and cleaned. After the specimens had been stressed for either 1, 30, 60, or 150 days by water and thermal cycling, retention was measured. RESULTS: The surface conditioning method, luting-gap size, and storage time significantly (P = .001; 3-way analysis of variance [ANOVA]) influenced retention. Air abrasion increased the retention significantly. Failure modes were predominantly adhesive. Air-abraded copings bonded with 30-microm luting gap achieved significantly greater retention than those bonded with a 60-microm luting gap. CONCLUSION: Surface conditioning methods and the size of the luting gap have a significant influence on the retention of Camlog zirconia ceramic copings bonded to Camlog titanium abutments.  相似文献   
960.
BACKGROUND: Securing transvenous left ventricular (LV) pacing leads without an active fixation mechanism in proximal coronary vein (CV) segments is usually challenging and frequently impossible. We investigated how active fixation leads can be safely implanted in this location, how to avoid perforating the free wall of the CV, and how to recognize and respond to perforations. MATERIALS AND METHODS: In five patients with no alternative to LV pacing from proximal CV segments, 4 Fr SelectSecure (Medtronic, Minneapolis, MN, USA) leads, which have a fixed helix, were implanted through a modified 6 Fr guide catheter with a pre-shaped tip (Launcher, Medtronic). RESULTS: Active fixation leads were successfully implanted in proximal CVs in five patients. There were no complications. Acute and chronic pacing thresholds were comparable to those of conventional CV leads. The pre-shaped guide catheter tip remains in close proximity to the myocardial aspect of the CV, directing the lead helix toward a safe implantation site. CONCLUSIONS: If only proximal CV pacing sites are available, 4 Fr SelectSecure leads can be safely implanted through a modified Launcher guide catheter, avoiding more invasive implantation techniques. Other than venous stenting or implantation of leads with retractable tines, SelectSecure leads are expected to remain extractable.  相似文献   
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