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1.
Many studies identify the risk factors for joining street gangs, but few explore disengagement. This article provides a systematic review of the factors which contribute to disengagement from gangs. Understanding this area is of paramount importance to developing policy and guiding practitioners working with this population, given the impact this lifestyle has on gang members and society as a whole. Seven academic databases, reference lists of relevant publications, an online search engine and a government database were used to identify relevant studies. Inclusion and exclusion criteria and quality assessment methods were employed. Data were then extracted and synthesised. Of 2515 citations, seven were found to have methodological rigour. The findings suggest there is not one definitive reason for gang exit but rather that multiple factors contribute. Variability was found in the quality scores. The limitations of this review are discussed, along with clinical implications and suggestions for future research.  相似文献   
2.
Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 1013 to 105 Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods.  相似文献   
3.
Stephenson  Joan 《JAMA》2006,295(15):1763
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5.
PURPOSE: A postoperative nomogram for prostate cancer recurrence after radical prostatectomy (RP) has been independently validated as accurate and discriminating. We have updated the nomogram by extending the predictions to 10 years after RP and have enabled the nomogram predictions to be adjusted for the disease-free interval that a patient has maintained after RP. METHODS: Cox regression analysis was used to model the clinical information for 1,881 patients who underwent RP for clinically-localized prostate cancer by two high-volume surgeons. The model was externally validated separately on two independent cohorts of 1,782 patients and 1,357 patients, respectively. Disease progression was defined as a rising prostate-specific antigen (PSA) level, clinical progression, radiotherapy more than 12 months postoperatively, or initiation of systemic therapy. RESULTS: The 10-year progression-free probability for the modeling set was 79% (95% CI, 75% to 82%). Significant variables in the multivariable model included PSA (P = .002), primary (P < .0001) and secondary Gleason grade (P = .0006), extracapsular extension (P < .0001), positive surgical margins (P = .028), seminal vesicle invasion (P < .0001), lymph node involvement (P = .030), treatment year (P = .008), and adjuvant radiotherapy (P = .046). The concordance index of the nomogram when applied to the independent validation sets was 0.81 and 0.79. CONCLUSION: We have developed and validated as a robust predictive model an enhanced postoperative nomogram for prostate cancer recurrence after RP. Unique to predictive models, the nomogram predictions can be adjusted for the disease-free interval that a patient has achieved after RP.  相似文献   
6.
OBJECTIVE: Tumors arising within augmentation cystoplasties are aggressive, have poor prognosis and the majority are not detected at follow-up cystoscopy. Genetic changes in tumors precede morphological abnormalities. Therefore, the aim of this study was to investigate whether genetic abnormalities detected by comparative genomic hybridization (CGH) could be used to identify those patients with augmentation cystoplasties at increased risk of tumorigenesis. METHODS: Bladder biopsy samples were obtained from 16 augmentation cystoplasty patients both distant from and near to the enterovesical anastomosis. CGH was used to detect genetic abnormalities in DNA extracted from the biopsies, archival specimens of two augmentation cystoplasties and two de novo bladder adenocarcinomas. RESULTS: A greater number of amplifications on 2p, 3q, 8q, 9p, 17p, 18pq and 20pq, were observed in bladder biopsies obtained near to the enterovesical anastomosis compared to those taken distant to the suture line. CGH of archival augmentation cystoplasty tumor DNA indicated abnormalities at several loci with amplifications at 2q, 5q, 10p and 21pq, while deletions occurred at 5p and 16p. CONCLUSIONS: The results of this study suggest that the urothelium adjacent to the bladder and/or bowel anastomosis in augmentation cystoplasties is genetically unstable. Furthermore, longitudinal studies are required to establish whether or not patients exhibiting genetic instability following augmentation cystoplasty are at greater risk of developing tumors than those with genetically stable epithelia.  相似文献   
7.
A total of 4470 pregnant women were screened for bacteriuria by the dipslide method and significant growth found in 226 (5.1%). In 198 cases the urine was re-examined, in 119 by using suprapubic aspiration or catheterisation (62 (52%) samples contained bacteria) and in 79 by using midstream urine samples (26 (33%) samples contained greater than 10(8) colony forming units/1), showing the maximum prevalence of confirmed bacteriuria to be 2.6%. Overt urinary tract infection developed later in four of 80 patients with proved bacteriuria who had been given antibiotics, in one of eight untreated patients with bacteriuria, in one of 110 patients with unconfirmed bacteriuria, and in one of 226 non-bacteriuric controls. A history of urinary tract infection was given by 18% of controls and 42% of women with confirmed bacteriuria. Screening for bacteriuria and treatment with antibiotics to prevent later overt infection is expensive. Whether it is worth while and cost effective depends largely on the prevalence of bacteriuria in the local population and the proportion who develop overt infection. The screening and treatment programme reported here appeared to prevent only six cases of overt infection.  相似文献   
8.
We have studied the fatigue rates of hydraulic pouches constructed in the form of a multilayered conical spiral using the latissimus dorsi muscle of 17 beagles. The roles that electrical muscle conditioning and early interruption of collateral blood supply have in the prevention of pouch fatigue were evaluated. The length of time that a pouch could generate flow in a hydraulic test system was measured; afterload was set at 80 mm Hg and preload 24 mm Hg. Pouches (N = 3) fashioned from muscles subject to neither electrical conditioning nor a vascular delay generated an initial flow of 990 +/- 346 ml/min, but could sustain flow for only 2.3, 3.8 and 3.6 minutes. Pouches (N = 5) constructed with electrically unconditioned muscles after a vascular delay (median 3 weeks) demonstrated a variable improvement in fatigue rates (initial flow 826 +/- 265 ml/min; time to no forward flow, 2.5, 7.5, 7.5, 10, and 200 minutes). Four of six pouches that received the benefit of long-term electrical muscle conditioning and a vascular delay (N = 6) were able to generate flow for a 4 hour period, at which time the experiment was terminated (initial flow 478 +/- 204 ml/min; final flow 195 +/- 157 ml/min). After the 4 hour fatigue test was completed, one electrically conditioned pouch was placed in series with the heart and served as a counterpulsator. The initial volume of blood pumped by the muscle pouch was 262 ml/min or 13.8% of cardiac output. After the pouch had contracted at a rate of approximately 45 beats/min for 1 hour, the volume of blood pumped was 178 ml/min, or 11% of cardiac output. In three other animals a pouch was fashioned and then left in situ for a 1 to 3 week period before hydraulic testing. These pouches generated significant initial flows (390 +/- 60 ml/min), which demonstrates the feasibility of further study of permanent pouches. These results suggest that permanent electrical muscle conditioning and perhaps a vascular collateral delay might permit an auxiliary skeletal muscle-powered ventricle to assume a portion of left ventricular function.  相似文献   
9.
Several studies have identified inadequacies in the care and treatment received by older patients with cancer, as opposed to their younger counterparts. These include over or under diagnosis, ineffective symptom management and lower survival rates in older people with cancer. Despite these inadequacies, there is lack of evidence of older peoples' perspectives regarding their cancer diagnosis and treatment. This on going 2-site hospital based study focuses on older people's perceptions of information and decision-making in relation to treatment for cancer by using a semi-structured interview schedule. Results of the pilot study with 6 patients are presented and discussed in the light of research and clinical implications.  相似文献   
10.
Background: There is considerable controversy regarding the role of subarachnoid 5% hyperbaric lidocaine in the syndrome transient radicular irritation (TRI). This randomized, double-blinded, prospective study was designed to determine the incidence of TRI and identify factors possibly contributing to its development.

Methods: One hundred fifty-nine ASA physical status 1 or 2 patients undergoing outpatient knee arthroscopy or unilateral inguinal hernia repair were prospectively randomized to receive spinal anesthesia with 5% hyperbaric lidocaine with epinephrine (60 mg with 0.2 mg epinephrine for arthroscopy or 75 mg with 0.2 mg epinephrine for hernia repair), 2% isobaric lidocaine without epinephrine (60 mg for arthroscopy or 75 mg for hernia repair), or 0.75% hyperbaric bupivacaine without epinephrine (7.5 mg for arthroscopy or 9.0 mg for hernia repair) in a double-blinded fashion. On the 3rd postoperative day, patients were contacted by a blinded investigator and questioned regarding the incidence of postoperative complications including TRI, defined as back pain with radiation down one or both buttocks or legs occurring within 24 h after surgery. Postoperatively, time from injection to block resolution, ambulation, voiding, and ready for discharge were recorded by a postanesthesia care unit nurse blinded to the group assignment.

Results: The incidence of TRI was greater in patients receiving lidocaine than in those receiving bupivacaine (16% vs. 0%; P = 0.003). There was no difference in the incidence of TRI between the patients receiving 59% hyperbaric lidocaine with epinephrine and those receiving 2% isobaric lidocaine without epinephrine (16% vs. 16%; P = 0.98). The incidence of TRI was greater in patients undergoing arthroscopy than in those undergoing hernia repair (13% vs. 5%; P = 0.04). There was no difference in discharge times in patients receiving bupivacaine versus those receiving hyperbaric lidocaine with epinephrine (292 vs. 322 min; P = 0.61).  相似文献   

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