448 research outputs found

    Correlates of sexual behaviors with health status and health perception in Chinese adolescents: A cross-sectional survey in schools

    Get PDF
    Sexual intercourse remains taboo among adolescents in a Chinese society such as Hong Kong. It is not openly discussed and little research has been done on its impact on health, although it carries serious risks of contracting sexually transmitted diseases (STDs)/HIV. In 1999, a cross-sectional, self-report survey on youth risk behaviors was carried out on 8382 students 15-18 years of age from 48 schools in Hong Kong. Three hundred seventy-seven (4.69%) reported that they had had sexual intercourse. Among them, forced sex (16.94%) was common, most often happening to boys (52.38%). They were more likely to have consulted doctors in the last month (odds ration [OR] 1.41 in boys 95% confidence interval [CI] 1.03, 1.94; OR 2.46 in girls 95% CI 1.81, 3.30) and 6 months (OR 1.33 in boys 95% CI 0.98, 1.78; OR 2.66 in girls 95% CI 1.80, 3.91). They also perceived poorer and deteriorating health. The sexually active female students were 6.70 times (95% CI 4.65, 9.66) more likely to attempt suicide than the other group and were more likely to take sick leaves (OR 3.56 in girls 95% CI 2.35, 5.41). Parental education and occupation, place of birth, and type of housing did not correlate in the initiation of sexual intercourse. The sexually experienced group reported worse physical and psychological health as well as health perception. Some of the characteristics and patterns identified in our study were quite different from the findings in the West but further studies are required to determine the reason for this.published_or_final_versio

    Conditional bounds for small prime solutions of linear equations

    Get PDF
    Let a 1, a 2, a 3 be non-zero integers with gcd(a 1 a 2, a 3)=1 and let b be an arbitrary integer satisfying gcd (b, a i, a j) =1 for i≠j and b≡a 1+a 2+a 3 (mod 2). In a previous paper [3] which completely settled a problem of A. Baker, the 2nd and 3rd authors proved that if a 1, a 2, a 3 are not all of the same sign, then the equation a 1 p 1+a 2 p 2+a 3 p 3=b has a solution in primes p j satisfying {Mathematical expression} where A>0 is an absolute constant. In this paper, under the Generalized Riemann Hypothesis, the authors obtain a more precise bound for the solutions p j . In particular they obtain A0. An immediate consquence of the main result is that the Linnik's courtant is less than or equal to 2. © 1992 Springer-Verlag.postprin

    Evaluating the incidence, clinical significance and predictors for vocal cord palsy and incidental laryngopharyngeal conditions before elective thyroidectomy: is there a case for routine laryngoscopic examination?

    Get PDF
    Background: Routine preoperative laryngeal examination remains controversial. We aimed to assess the utility of preoperative routine flexible laryngoscopy (FL) by looking at the incidence, clinical significance and predictors for preoperative vocal cord paresis (VCP) and incidental laryngopharyngeal conditions (LPC) in our consecutive cohort. Methods: A total of 302 patients underwent laryngeal examination by an independent otorhinolaryngologist and were specifically asked about voice/swallowing symptoms suggestive of VCP 1 day before surgery. As well as vocal cord (VC) mobility, the naso-pharynx and larynx were examined using FL. Any VCP and/or LPC was recorded. VCP was defined as reduced or absent movement in one or more VC. An LPC was considered clinically significant if the ensuing thyroidectomy was changed or deferred. Results: Seven (2.3 %) patients had preoperative VCP, while an additional seven patients had an incidental LPC. Of the seven VCPs, five were caused by previous thyroidectomy, while two were caused by a benign goitre. The incidence of asymptomatic VCP in a previously non-operated cohort was 1/245 (0.41 %). Voice/swallowing symptoms (p = 0.033) and previous thyroidectomy (p < 0.001) were the two significant predictors for VCP. The seven incidental LPCs were vallecular cyst (n = 1), VC scar and polyp (n = 2), nasopharyngeal cyst and polyp (n = 3) and redundant arytenoid mucosa (n = 1); however, as they were benign, all seven patients proceeded to thyroidectomy as planned. Conclusions: Given the low incidence (0.41 %) of asymptomatic VCP in a previously non-operated cohort and that none of the seven LPCs were considered clinically significant, routine preoperative laryngoscopic examination should be reserved for those with previous thyroidectomy and/or voice/swallowing symptoms. © 2013 Société Internationale de Chirurgie.postprin

    Time is brain - only part of the story: role of CT perfusion in workup for mechanical thrombectomy in acute stroke

    Get PDF
    Theme: Brain Attack: A New EraFree Paper VIIIPURPOSE: Recent randomized controlled studies have shown favorable results for endovascular treatment of acute ischemic stroke, which signifies a new era in stroke management. Mechanical thrombectomy, in addition to intravenous thrombolysis, in treatment of acute stroke with large artery occlusion in the anterior circulation up to 6 hours after symptom onset is now level 1a evidence. However, there is no well-established universal consensus regarding the imaging workup protocol for acute stroke patients, which differ amongst these trials. We believe computed tomographic (CT) perfusion imaging, with its ability to identify irreversibly damaged ...postprin

    Three-dimensional graphene based passively mode-locked fiber laser

    Get PDF
    © 2014 Optical Society of America. We present an all-fiber passively mode-locked fiber laser incorporating three-dimensional (3D) graphene as a saturable absorber (SA) for the first time to the best of our knowledge. The 3D graphene is synthesized by template-directed chemical vapor deposition (CVD). The SA is then simply formed by sandwiching the freestanding 3D graphene between two conventional fiber connectors without any deposition process. It is demonstrated that such 3D graphene based SA is capable to produce high quality mode-locked pulses. A passively mode-locked fiber laser is constructed and stable output pulses with a fundamental repetition rate of ∼9.9 MHz and a pulse width of ∼1 ps are generated from the fiber laser. The average output power of the laser is ∼10.5 mW while the output pulse is operating at single pulse region. The results imply that the freestanding 3D graphene can be applied as an effective saturable absorption material for passively mode-locked lasers

    The association between internet addiction and psychiatric co-morbidity: A meta-analysis

    Get PDF
    Background: This study evaluates the association between Internal Addiction (IA) and psychiatric co-morbidity in the literature.Methods: Meta-analyses were conducted on cross-sectional, case-control and cohort studies which examined the relationship between IA and psychiatric co-morbidity. Selected studies were extracted from major online databases. The inclusion criteria are as follows: 1) studies conducted on human subjects; 2) IA and psychiatric co-morbidity were assessed by standardised questionnaires; and 3) availability of adequate information to calculate the effect size. Random-effects models were used to calculate the aggregate prevalence and the pooled odds ratios (OR).Results: Eight studies comprising 1641 patients suffering from IA and 11210 controls were included. Our analyses demonstrated a significant and positive association between IA and alcohol abuse (OR = 3.05, 95% CI = 2.14-4.37, z = 6.12, P < 0.001), attention deficit and hyperactivity (OR = 2.85, 95% CI = 2.15-3.77, z = 7.27, P < 0.001), depression (OR = 2.77, 95% CI = 2.04-3.75, z = 6.55, P < 0.001) and anxiety (OR = 2.70, 95% CI = 1.46-4.97, z = 3.18, P = 0.001).Conclusions: IA is significantly associated with alcohol abuse, attention deficit and hyperactivity, depression and anxiety. © 2014 Ho et al.; licensee BioMed Central Ltd
    • …
    corecore