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111.
CONTEXT In the United States, young people aged 15–24 represent 25% of the sexually experienced population. However, the incidence and prevalence of sexually transmitted diseases (STDs) among this age-group are unknown.
METHODS Data from a variety of sources were used to estimate the incidence and prevalence of STDs among 15–24-year-olds in the United States in 2000. The quality and reliability of the estimates were categorized as good, fair or poor, depending on the quality of the data source.
RESULTS Approximately 18.9 million new cases of STD occurred in 2000, of which 9.1 million (48%) were among persons aged 15–24. Three STDs (human papillomavirus, trichomoniasis and chlamydia) accounted for 88% of all new cases of STD among 15–24-year-olds.
CONCLUSIONS These estimates emphasize the toll that STDs have on American youth. More representative data are needed to help monitor efforts at lowering the burden of these infections.  相似文献   
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BACKGROUND: Hormonal factors may play a more prominent role in cervical adenocarcinoma than squamous cell carcinoma. The authors evaluated whether obesity, which can influence hormone levels, was associated with adenocarcinoma and squamous cell carcinoma. METHODS: This case-control study included 124 patients with adenocarcinoma, 139 matched patients with squamous cell carcinoma, and 307 matched community control participants. All participants completed interviews and provided cervicovaginal samples for human papillomavirus (HPV) testing. Polytomous logistic regression-generated odds ratios (ORs) and 95% confidence intervals (95% CIs) for self-reported height and weight, body mass index (BMI; kg/m(2)), and measured waist-to-hip ratio (WHR) for both histologic types were adjusted and stratified for HPV and other confounders. RESULTS: Height, weight, BMI, and WHR were positively associated with adenocarcinoma. BMI >or= 30 kg/m(2) (vs. BMI < 25 kg/m(2); OR, 2.1 and 95% CI, 1.1-3.8) and WHR in the highest tertile (vs. the lowest tertile; OR, 1.8 and 95% CI, 0.97-3.3) were associated with adenocarcinoma. Neither height nor weight was found to be associated with squamous cell carcinoma, and associations for BMI >or= 30 kg/m(2) (OR, 1.6) and WHR in the highest tertile (OR, 1.6) were weaker and were not statistically significant. Analyses using only HPV positive controls showed similar associations. The data were adjusted for and stratified by screening, but higher BMI and WHR were associated with higher disease stage at diagnosis, even among recently and frequently screened patients with adenocarcinoma. Thus, residual confounding by screening could not be excluded as an explanation for the associations. CONCLUSIONS: Obesity and body fat distribution were associated more strongly with adenocarcinoma than with squamous cell carcinoma. Although questions about screening remain, obesity may have a particular influence on the risk of glandular cervical carcinoma.  相似文献   
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BACKGROUND: Because apomorphine is a dopamine agonist that acts on areas of the central nervous system believed to mediate penile erection, its use in erectile dysfunction (ED) has been investigated. However, it also produces nausea by dopamine-receptor stimulation of the chemotrigger zone in the brain. Therefore, a low plasma concentration, achieved rapidly, would be selective for the desired erectile response but would be below the dopamine threshold for nausea. OBJECTIVE: We evaluated the efficacy and tolerability of a dose-optimized regimen of a sublingual formulation of apomorphine (apomorphine SL) in the treatment of ED. METHODS: This was a multicenter, open-label, uncontrolled, Phase III dose-optimization study of apomorphine SL in heterosexual men with ED. The 2-week screening period, during which baseline severity of ED was determined using the International Index of Erectile Function, was followed by a 3-week dose-optimization period beginning at a dose of 2 mg. Patients were to make at least 2 attempts at intercourse per week throughout the study, placing 1 apomorphine tablet under the tongue beforehand. At the end of the first week, the dose could be increased to 3 mg at the discretion of the investigator; at the end of the second week, the dose could be increased to a maximum of 4 mg or decreased as needed. In the following 4-week treatment period, patients took their individual optimal doses. The primary efficacy variable was the percentage of attempts resulting in erections firm enough for intercourse, as assessed by investigators' review of data from patients' diaries. Secondary variables included the percentage of attempts resulting in successful intercourse, time to erection, and duration of erection. Information about adverse events, including their severity and relation to treatment, was determined on the basis of direct questioning, spontaneous reports, and review of patient diaries. RESULTS: The study enrolled 849 heterosexual men whose ages ranged from 31 to 78 years (mean, 58.1 years). They had a mean 5.7-year history of ED of varbus causes. ED was mild in 11.5% of the men, moderate in 23.8 c, and severe in 48.1%. When results of the last 8 attempts were pooled, representing the period during which patients were taking their optimal doses of apomorphine SL, the mean percentage of attempts resulting in erections firm enough for intercourse was 39.4%, compared with 13.1% at baseline; attempts resulting in intercourse increased from a mean of 12.7% at baseline to 38.3% with treatment. The average median time to erection was 23 minutes, and the average median duration of erection was 13 minutes. Nausea, the most common treatment-related adverse event (11.7%). was dose related and diminished with continued dosing. One patient had a single syncopal episode that was judged to be related to apomorphine SL. CONCLUSIONS: In the present study, a dose-optimization regimen of apomorphine SL-with dosing initiated at 2 mg and adjusted up to a maximum of 4 mg as needed-was effective and well tolerated in the treatment of ED, regardless of its cause or severity.  相似文献   
115.
Background. The temporal evolution of lung injury followingpost-traumatic shock is poorly understood. In the present studywe have tested the hypothesis that manifestations of pulmonaryvascular dysfunction may be demonstrable within the first hourafter the onset of shock. Methods. Twenty-nine anaesthetized pigs (mean weight 27.4 kg;(SD) 3.2) were randomly allocated to three groups: control (C,n=9), shock resuscitated with either NaCl 0.9% (S, n=10), or4% gelatine (G, n=10). Shock was maintained for 1 h followedby fluid resuscitation with either normal saline or 4% gelatinesolution. Cardiac output (CO), mean arterial pressure (MAP),mixed venous saturation (SvO2), blood lactate concentration,mean pulmonary artery pressure (MPAP), MPAP/MAP, pulmonary vascularresistance (PVR), extravascular lung water index (EVLWi), PaO2/FIO2,venous admixture (Q·S/Q·T), and dynamic lung compliance(Cdyn) were measured at baseline, beginning of shock phase,end of shock phase, and post-resuscitation. Results. At the end of volume resuscitation CO was restoredto control values in both shock groups. MAP remained significantlybelow control values (95% CI: C=70–95, S=28–52,G=45–69 mm Hg) in both shock groups. MPAP/MAP was significantlygreater in both shock groups at the end of the shock phase (95%CI; C=0.15–0.24, S=0.28–0.38, G=0.32–0.42)and at the post-resuscitation phase (95% CI: C=0.12–0.30,S=0.43–0.61, G=0.32–0.49) indicating the presenceof relative pulmonary hypertension. This was associated witha significant increase in PVR in Group S (F=3.9; P<0.05).There were no significant changes in PaO2/FIO2, Q·S/Q·T,EVLWi, or Cdyn. In a small cohort of animals a measurable increasein EVLWi (>30%) and reduction in Cdyn (>10%) were observed. Conclusions. Pulmonary vascular injury manifesting as relativepulmonary hypertension and increased PVR may occur within thefirst hour after the onset of shock. These changes may not beaccompanied by overt changes in oxygenation, compliance, orEVLWi. Br J Anaesth 2003; 91: 224–32  相似文献   
116.
Airway management after maxillectomy: routine tracheostomy is unnecessary   总被引:2,自引:0,他引:2  
Lin HS  Wang D  Fee WE  Goode RL  Terris DJ 《The Laryngoscope》2003,113(6):929-932
OBJECTIVES/HYPOTHESIS: There is a paucity of data to guide the optimal management of the airway in patients after maxillectomy. The decision on whether a concomitant tracheostomy is needed is often dictated by the surgeon's training and experience. We reviewed our experience with maxillectomy to assess the need for tracheostomy in postoperative airway management. STUDY DESIGN: Retrospective analysis at a university hospital. METHODS: We identified 121 patients who underwent 130 maxillectomies between October 1990 and September 2001. Twenty-four of these were total (all six walls removed), 45 were subtotal (two or more walls removed), and 61 were limited (only one wall removed). Reconstruction ranged from none to microvascular free flap, with split-thickness skin graft being the most common reconstructive option. RESULTS: Only 10 tracheostomies (7.7%) were performed at the time of maxillectomy. These included four tracheostomies in patients who underwent bulky flap reconstruction, two tracheostomies in patients who underwent both flap reconstruction and mandibulectomy, one tracheostomy in a patient who underwent mandibulectomy, one tracheostomy in a patient with mucormycosis in anticipation of prolonged ventilatory support postoperatively, and two tracheostomies at the surgeons' discretion because of concern for upper airway edema. Among the 111 patients who underwent 120 maxillectomies without concomitant tracheostomy, 1 patient (0.9%), a 74 year-old man with oxygen-dependent chronic obstructive pulmonary disease, required repeat intubation on day 3 and again on day 10 after the surgery, because of respiratory failure; fiberoptic examination confirmed the absence of upper airway compromise. CONCLUSIONS: The routine performance of tracheostomy in patients undergoing maxillectomy is unnecessary. Selective use of tracheostomy may be indicated in situations in which mandibulectomy or bulky flap reconstruction is performed or a concern for postoperative oropharyngeal airway obstruction because of edema or packing exists.  相似文献   
117.
OBJECTIVES: This article compares a linear risk-adjusted model of medical expenditures for Medicare patients with a model that explicitly account for skewness in distribution of expenditures. METHODS: A model of expenditures and a model of the square root of expenditures, each expressed as linear combinations of risk adjusters, are estimated using data from the 1992 through 1994 Medicare Current Beneficiary Surveys. Five sets of risk adjusters are considered. Each combination of model and set of risk adjusters is tested for linearity, heteroscedasticity, in-sample fit (R2), forecast performance (forecast bias and forecast mean squared error), and overfitting the data. We analyze forecast performance (1)based on forecasts in same year used for estimation, and (2)based on forecasts in the year following that used for estimation. RESULTS: In the first analysis, the model using a square root transformation of expenditures as the dependent variable and the more parsimonious specification of risk adjusters performs best in terms of forecast squared error and overfitting. The untransformed model performs best in terms of forecast bias in each group based on severity of disability, with the exception of the severely disabled for whom the square root model is best. In the second analysis, the square root model performs better than the untransformed model in terms of forecast squared error, but neither model is statistically distinguishable from zero in terms of bias. CONCLUSIONS: Accounting for skewness in expenditures tends to improve precision but not necessarily bias, except among the severely disabled. Adjusting for health status improves risk adjustment.  相似文献   
118.
It is often difficult to interpret the clinical or policy significance of findings from mental health research when results are presented only in terms of statistical significance. Results expressed in terms of p values or as a metric corresponding to a mental health status scale are seldom intuitively meaningful. To help interpret the significance of research results, we demonstrate a social validity approach that relates scores on mental health status scales to four subsequent major life events. A logistic regression model is used to estimate the relation between mental health status scores and the probability of subsequent major life events, using data obtained on Medicaid beneficiaries with schizophrenia from an evaluation of the Utah Prepaid Mental Health Plan. Using this relatively simple approach will demonstrate to policy makers, clinicians, and researchers the social impact of an outcome, thereby aiding in the interpretation of the significance of results.  相似文献   
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