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91.
OBJECTIVE: To determine the prevalence of suicidal ideation and the symptomatic profile as well as to identify the sociodemographic characteristics highlighting female adolescents with the highest scores on suicidal ideation in adolescents living in Mexico City: students and suicidal patients. MATERIAL AND METHODS: A cross-sectional and ex-post-facto study was carried out in order to analyze information from two samples: 1,712 junior and junior high school women students (representative student sample in Mexico City), and 30 adolescents inpatient hospitalized for her suicide attempts (clinical sample). RESULTS: Prevalence of presence as well as persistence of suicidal ideation were higher in the clinical sample, nevertheless 11.8% of the school sample had everyone of the symptoms in a range of 1 to 7 days. The most persistent of the ideation symptoms was: "My family would be better if I were dead"; and in the clinical sample it was "I thought about killing myself". Finally, the sociodemographic characteristics that best matched the student girls having the highest scores in suicidal ideation were: to be on junior high school, to get low grades, to acknowledge school performance as bad and to have interrupted her studies. The characteristics that highlight the girls with a first attempt were analyzed in the clinic sample in comparison with those ones with two or more attempts. It was significant that girls in the second group were living only with one parent and they thought in the last attempt that their dead would be possible or certain. CONCLUSIONS: The prevalence of suicidal ideation was important in the school sample. If it is considered that this psychological construct has a strong association with suicidal attempt, and multiple suicide conduct, then is a priority to detect adolescents in risk and to make preventive efforts, considering the sociodemographic characteristics that configurate in risk for suicidal ideation. 相似文献
92.
SD Colman SA Rasmussen VT Ho CR Abernathy MR Wallace 《Canadian Metallurgical Quarterly》1996,58(3):484-490
Using loss of heterozygosity analysis, a method designed to detect moderate to large gene deletions, we have identified a new-mutation neurofibromatosis type 1 (NF1) patient who is somatically mosaic for a large maternally derived deletion in the NF1 gene region. The deletion extends at least from exon 4 near the 5' end of the gene to intron 39 near the 3' end. The gene-coding region is, therefore, mostly or entirely deleted, encompassing a loss of > or = 100 kb. We hypothesize that the deletion occurred at a relatively early developmental timepoint, since signs of NF1 in this patient are not confined to a specific body region, as seen in "segmental" NF, and since both mesodermally and ectodermally derived cells are affected. This report provides the first molecular evidence of somatic mosaicism in NF1 and, taken together with a recent report of germ-line mosaicism in NF1, adds credence to the concept that mosaicism plays an important role in phenotypic and genetic aspects of NF1 and may even be a relatively common phenomenon. 相似文献
93.
垂直搜索是针对某一个行业的专业搜索引擎,是搜索引擎的细分和延伸,是对网页库中的某类专门的信息进行一次整合,定向分字段抽取出需要的数据进行处理后再以某种形式返回给用户。该文结合使用Heritrix与Lucene对学校新闻网站网页进行抓取并建立索引,建立相对应的新闻垂直搜索引擎系统。 相似文献
94.
RE Falcone SR Wanamaker F Barnes CG Baxter SA Santanello 《Canadian Metallurgical Quarterly》1993,3(4):325-329
The number of people smoking free-base cocaine, or "crack," has increased dramatically in recent years. Concomitantly, the literature describing complications of such use has grown as well. Adverse pulmonary effects are being increasingly noted, such as respiratory symptoms, pulmonary hemorrhage, pulmonary edema, asthma, and pulmonary barotrauma. These and other pulmonary effects are reviewed. 相似文献
95.
Histological and histochemical techniques have been employed to determine the structure and autonomic innervation of paraganglia located in the human pelvis. In foetal and early postnatal tissues, paraganglia formed rounded cellular masses which were frequently in company with the autonomic nerves and ganglia of the urinary bladder and other pelvic viscera. The constituent cells contained only small amounts of cholinesterase and were unrelated to enzyme positive autonomic nerves; acetylcholinesterase containing nerves were occasionally observed in the capsule and the fibrous septa of the pelvic paraganglia. In early postnatal specimens, pelvic paraganglia frequently contained single or multiple "pacinian-like" corpuscles, each possessing a central region which was rich in both acetyl and pseudocholinesterase. These structures were rarely observed within autonomic ganglia and were absent 4 1/2 years post partum. By means of a histochemical technique, pelvic paraganglia were found to contain catecholamine which was attributed to the presence of relatively large quantities of noradrenaline. These observations have been discussed with particular reference to the results of other studies on the autonomic innervation of paraganglia. 相似文献
96.
The right eye of a 9-year-old white boy with Best's vitelliform macular dystrophy had an intact egg-yolk lesion and a retinal pigment epithelial defect superiorly, suggesting an early pseudohypopyon stage. The disruptive phase of the left eye showed subretinal hemorrhages, a "signet ring," and a subretinal neovascular membrane. 相似文献
97.
BW Hess EJ Scholljegerdes SA Coleman JE Williams 《Canadian Metallurgical Quarterly》1998,76(7):1767-1777
Primiparous beef cows (n = 35 Bos taurus, average initial BW of 498 kg) were allotted to treatments in a split-plot designed experiment to determine the effects of supplemental ruminally protected amino acids on cow and calf productivity and metabolic changes in the cows. Cows were fed chopped annual rye hay at 1.5% of BW. The following treatments were used: 1) .8 kg soybean hulls, 1.4 kg ground corn, .6 kg soybean meal (CON); 2) 1.4 kg ground corn, 1.4 kg soybean meal (PRO); 3) PRO plus ruminally protected methionine and lysine (supplied 5 and 10 g, respectively; PRO1); and 4) PRO with twice the level of ruminally protected amino acids in PRO1 (PRO2). Cow weight gain was not different (P > .26) among treatments and averaged 1.2 kg/d for the 45 + 6 d before parturition. After parturition, cow weight gain did not differ (P > .47) between CON and PRO treatments, but it decreased quadratically (P < .01) with increasing level of ruminally protected amino acids. Total milk yield, protein, and fat (4 h) were greater (P < .05) for cows consuming PRO supplements than for CON, whereas CON cattle tended (P = .11) to lose less body condition. Total milk protein showed a quadratic increase (P < .05) in response to level of ruminally protected amino acids that was the inverse of the quadratic response noted for cow weight gain. Serum urea N concentration was greater (P = .07) for cattle consuming additional protein. Metabolic hormones were not affected (P > .18) by dietary treatment, but they responded (P < .05) to changes in physiological state. Supplements with additional protein supported greater (P = .0001) milk urea N concentration and output. Milk urea N concentration increased (P < .05) and milk IGF-I decreased (P < .05) as the lactation period progressed. The measurement of CON and PRO diets revealed that supplements with additional soybean meal had greater (P < .05) DM and N degradation; the extent of forage DM and NDF degradation was similar (P > .05) among treatments. Production shifted away from body weight gain to increased milk protein production when daily supplementation of ruminally protected methionine and lysine increased from 5 and 10 to 10 and 20 g, respectively. This shift in production was not reflective of changes in the metabolic regulators measured. 相似文献
98.
分层介质动态力学性能的实验研究 总被引:1,自引:0,他引:1
采用Φ75mm分离式霍普金森压杆实验装置,对由普通混凝土与泡沫混凝土组合的分层介质的动态力学性能进行了研究。结果表明,应力波通过普通混凝土时的衰减仅为其原来峰值的5%~10%,应力波通过泡沫混凝土时其峰值衰减为原来的1/5。由此说明在含泡沫混凝土与普通混凝土的分层介质中,泡沫混凝土提供削波与延缓应力波作用时间的作用,普通混凝土则为其提供较高强度。通过对分层介质应力衰减和动量变化的分析表明,分层介质在动态力学行为上表现为较大的塑性和应变率相关性,其应力衰减主要取决于泡沫混凝土材料。 相似文献
99.
Kemeny S.E. Torbey H.H. Meadows H.E. Bredthauer R.A. La Shell M.A. Fossum E.R. 《Solid-State Circuits, IEEE Journal of》1992,27(3):398-405
Four image reorganization ICs that enable real-time difference encoding for hierarchical lossless image compression are reported. Two image reorganization processors are realized on the focal-plane and two are designed for hybridization to a separate imager IC. The two focal-plane ICs represent the first integration of a 256×256 buried-channel frame-transfer CCD image sensor with additional charge-domain circuitry to enable image reformatting at video rates (28 frames/s). The four ICs generate pyramidal pixel output in 3×3 blocks with the center pixel first. Pixel data reorganization is performed through simultaneous readout of three rows of data, followed by pixel resequencing and sampling to provide differential output. A novel architecture provides simultaneous readout of multiple imager rows on the focal-plane ICs. The ICs have achieved a charge-transfer efficiency (CTE) of 0.99996 in the conventional horizontal and vertical CCD registers, and a CTE of 0.99994 in the SP3 registers 相似文献
100.