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Frequency of symptoms of depression and selected health-related practices and events were measured in a sample of 219 high school students. Students reported numerous symptoms of depression. Relative proportions of boys and girls reporting symptoms of depression were not significantly different. However, girls reported experiencing more severe depression than their male counterparts. Depression correlated significantly with several of the 22 health practices and states of affect examined. Both the determinants and manifestations of depression in adolescent cohorts require in-depth investigation. Possible implications for school health personnel are discussed.  相似文献   
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S L Zeger  S D Harlow 《Growth》1987,51(1):1-21
Mathematical models of size and shape have played a prominent role in the first half century of Growth. In honor of the fiftieth anniversary of the journal, this paper reviews the development of these models. An historical perspective is taken with a focus on the changing context in which mathematical models have been studied. Early models were thought to represent principles or laws of growth. Today, models are viewed as tools for biologic analysis. We trace this contextual shift through specific models developed and used in Growth.  相似文献   
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This paper describes the evaluation of a new method of natural family planning (NFP) in Liberia. The Modified Mucus Method (MMM) was developed to address the need for a simple method of charting for poor and illiterate women. The acceptance, use, and cost-effectiveness of the MMM were compared with standard NFP methods, the sympto-thermal and ovulation method (ST/OM), used in the same population.The personal discontinuation rate of MMM users was 27.3 per 100 women per year compared with 3.2 among ST/OM users. Unplanned pregnancy rates were low for both MMM and ST/OM, 6.6 and 1.5 respectively. The cost per couple year protection (CYP) for MMM was $55.80 and for ST/OM $56.10. There were differences in characteristics between MMM and ST/OM clients. The MMM clients were more likely to have attended school and to have used a family planning method previously, and were less likely to be housewives.We conclude that the MMM in Liberia was provided to an inappropriate sample of women, educated and middle-class rather than poor and illiterate. The MMM users were dissatisfied and discontinued at the rate of 44 per 100 women entering per year. This is an unfair evaluation of the MMM because of the unsuitable study population. It is our opinion that the MMM needs more study to become part of the inventory of birth spacing methods.
Resumen Este trabajo describe la evaluación de un nuevo método de planificación familiar natural (PFN) in Liberia. El Método del Moco Modificado (MMM) se desarrolló a fin de atender a la necesidad de un método sencillo de registro para mujeres pobres y analfabetas. La aceptación, el uso y la eficacia en función de los costos del MMM se comparó con los métodos estándares de PFN, el Método Sintotérmico y de Ovulación (ST/OM), utilizado en la misma población.La tasa de abandono personal de las usuarias del MMM fue 27,3 por cada 100 mujeres por año en comparación con 3,2 entre las usuarios del ST/OM. El costo por protección-año de la pareja en le caso del MMM fue $55,80 y el del ST/OM $56,10. Hubo características diferentes entre las usuarias del MMM y del ST/OM. Había más probabilidades de que las usuarias del MMM hubieran asistido a la escuela y utilizado métodos de planificación familiar anteriormente, y menos probabilidades de que fueran amas de casa. Llegamos a la conclusión de que el MMM en Liberia era proporcionado a una muestra inadecuada de mujeres, más bien educadas y de clase media que pobres y analfabetas. Las usuarias del MMM estaban insatisfechas y lo abandonaron a razón de 44 por cada 100 mujeres que lo adoptaban por año. Esta es una evaluación injusta del MMM debido a lo inadecuado de la población del estudio. Opinamos que el MMM requiere mayores estudios para poder llegar a integrar el inventario de métodos de espaciamiento de nacimientos.

Resumé Le présent exposé décrit l'évaluation d'une nouvelle méthode de planning familial naturel au Libéria. La méthode de modification des glaires (MMM) a été mise au point pour satisfaire au besoin de disposer d'une méthode simple pouvant être appliquées par les femmes pauvres et analphabètes. L'acceptation, l'utilisation et l'efficacité de cette méthode par rapport à son coût ont été comparées à celles d'autres méthodes de planning familial naturel, à la méthode sympto-thermique et de l'ovulation (ST/O), appliquées dans cette même population.Le taux d'abandon de la MMM pour des raisons personnelles s'est élevé à 27,3 par an, alors qu'il était de 3,2 chez les femmes utilisant la méthode ST/O. Le nombre des grossesses non planifiées était faible pour l'une et l'autre des méthodes, soit 6,6 pour la MMM et 1,5 pour la méthode ST/O. Le coût annuel de la protection par couple se situait à $55,80 pour la première méthode et à $56,10 pour la seconde. Les femmes présentaient des caractéristiques différentes d'un groupe à l'autre. Celles qui utilisaient la MMM étaient plus souvent susceptibles d'avoir été scolarisées et d'avoir auparavant utilisé une méthode de planning familial, et moins susceptibles d'être des ménagères.Nous en avons conclu que la MMM avait été mise à la disposition d'un groupe de femmes éduquées, de classe moyenne, à qui elle ne convenait pas, plutôt qu'à des femmes pauvres et analphabètes. Les utilisatrices n'en étant pas satisfaites, elles avaient abandonné la méthode à un pourcentage de 44 pour cent femmes l'essayant chaque année. Cette évaluation de la MMM n'est pas valable car cette méthode n'était pas adaptée à la population étudiée. Nous estimons qu'il est nécessaire d'étudier plus en profondeur la MMM si l'on veut qu'elle fasse partie de l'ensemble des méthodes visant à espacer les naissances.
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A study of the prevalence of nosocomial colonisation and nosocomial infection (NI) was conducted in the paediatric respiratory intensive care unit of a large teaching hospital serving a developing community. Surveillance specimens were collected regularly from 63 consecutive patients admitted over 4 months, and also from professional staff, boarder mothers, cleaners and the unit environment. The incidence among patients of colonisation (40%) and of NI (43%) was high. The risk of dying in children with NI was appreciably increased (relative risk 2,241, confidence interval 0,591-8,503). This did not reach statistical significance, probably because so few children escaped acquiring hospital organisms. The significant risk factor for acquiring colonisation (P = 0.008) and NI (P < 0.0001) was a ward stay of more than 10 days. In addition, for acquiring NI an age of under 6 months was also predictive (P = 0.0298). The nature of the primary illness dictated the time spent in the ward; an important proportion of patients had preventable diseases, such as measles, pneumonia and tetanus, which required prolonged treatment. All children with endotracheal intubation had hospital-acquired organisms in tracheal aspirates. Eighty-two per cent of children developed positive gastric aspirates, 17% a positive urine culture and 11% a positive blood culture. Colonisation occurred rapidly; organisms initially appeared in gastric aspirates (mean 2 days), then in tracheal aspirates (mean 5 days) and urine cultures (mean 10 days). The acquired organisms, many of which were antibiotic-resistant, were almost exclusively enteric Gram-negative bacilli (GNB) and Staphylococcus aureus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Conclusions Although much attention is being given to the design of the anesthesia workstation of the next century, significant opportunities exist to improve current systems. There have been sufficient technological advances that enable immediate improvement on current techniques and methodologies. As this team realized, much can be done to improve the workstation of the immediate future.  相似文献   
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BACKGROUND: Ten percent of gastric cancer (GC) cases are familial, with one third resulting from a mutation in the tumor suppressor gene CDH1. Loss of this important structure can result in hereditary diffuse gastric cancer (HDGC), which carries a high mortality if early diagnosis is not made. Despite its clear genetic origin, optimal management of HDGC family members is controversial, as the utility and efficacy of current cancer screening programs for mutation carriers are unproven. METHODS: A 53-year-old Caucasian woman was initially seen for genetic screening because multiple family members had mutations of the CDH1 gene. Her pedigree analysis demonstrated 4 generations of gastric cancer, and 2 of the generations carried the CDH1 germline mutation, consistent with HDGC. At endoscopy, the patient's gastric mucosa was normal and random biopsies were also normal. The patient underwent a laparoscopic total gastrectomy. RESULTS: The gross examination of her stomach appeared normal. On histologic examination, however, the stomach was found to have diffuse (signet ring cell) adenocarcinoma in-situ with 11 microscopic foci of invasive adenocarcinoma limited to the lamina propria. CONCLUSION: Our case is the first reported prophylactic total gastrectomy utilizing a laparoscopic approach, and it highlights the importance of taking a thorough family history and obtaining a pedigree analysis. Endoscopic screening in HDGC cannot rule out diffuse GC, because the stomach and biopsies can be normal despite the presence of adenocarcinoma. Therefore, our case supports the recommendation for prophylactic gastrectomy in HDGC.  相似文献   
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It has become increasingly apparent that resident fish can develop resistance to chemicals in their environment, thus compromising their usefulness as sentinels of site-specific pollution. By using a stream system whose resident fish appear to have developed pollutant resistance (Brammell et al., Mar Environ Res 58:251–255, 2005), we tested the hypothesis that the pollutant-inducible biomarker, cytochrome P4501A (CYP1A), as measured in field-caged juvenile rainbow trout (Oncorhynchus mykiss), would reflect relative pollution differences between reference and polychlorinated biphenyl (PCB)-contaminated sites. Trout were caged in the Town Branch/Mud River system (Logan County, KY), a stream system undergoing remediation for PCBs. Fish were held in remediated (Town Branch), unremeditated (Mud River), and reference sites for 2 weeks during spring 2002. At the end of this period, gill and hepatic CYP1A expression were measured. To evaluate the relative PCB exposure of caged trout and provide a reference point against which to calibrate CYP1A response, PCB levels were quantified in sediments from each site. Hepatic CYP1A expression in caged trout clearly detected the presence of PCBs in the Town Branch/Mud River stream system. Sediment PCB levels and hepatic CYP1A expression in caged trout produced identical pollution rankings for the study sites. Gill CYP1A expression, although suggestive of site differences, was not statistically different among sites. Unlike resident fish, which failed to show site differences in hepatic CYP1A expression in this waterway (Brammell et al. 2005), caged fish proved to be a sensitive discriminator of relative PCB contamination in this system. In summary, we determined that CYP1A expression in caged fish reflected relative in situ pollutant exposure. The exposure paradigm confirmed that 2 weeks was a sufficient caging period for evaluating CYP1A response in this species at these temperatures (13–19°C). In addition, these studies demonstrate that tissue-specific CYP1A expression can provide insights into likely routes of exposure. We conclude that CYP1A expression in caged trout is a reliable and inexpensive first-pass determination of relative environmental pollutant exposure and bioavailability in aqueous systems.  相似文献   
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