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81.
Objective. To assess the value of head ultrasound (HUS) in neurologically normal infants with macrocephaly and to develop a rational approach to radiological investigation of macrocephalic infants. Materials and methods. A retrospective analysis of infants with macrocephaly (seen by one pediatric neurologist at this institution) was conducted. Infants with normal neurological examinations, no evidence of raised intracranial pressure and who had undergone a HUS were included. Results. Twenty-seven infants were included in the analysis. Mean age at first assessment was 4.8 months. In 12 of 27 (44 %), HUS was reported as normal. The remaining 15 had clinically insignificant abnormalities on HUS; 7 had prominent ventricles and 7 had increased subarachnoid fluid, with 1 infant having both. Seven infants had CT or MRI in addition to HUS. No clinically significant abnormalities were seen on CT or MRI scans that were not evident on HUS. Four infants had mild developmental abnormalities on initial evaluation. Mean duration of follow-up was 13.1 months. No infant developed neurological abnormalities during the follow-up period. Conclusion. In infants with macrocephaly with a normal neurological examination and no signs of raised intracranial pressure, HUS in conjunction with close neurological follow-up is reliable for the detection or exclusion of relevant intracranial pathology. Received: 22 May 1997 Accepted: 24 October 1997  相似文献   
82.
CONTEXT: Despite advances in early detection and prevention of cervical cancer, women living in rural areas, and particularly in Appalachia, the rural South, the Texas/Mexico border, and the central valley of California, have had consistently higher rates of cervical cancer mortality than their counterparts in other areas during the past several decades. METHODS: This paper reviews the published literature from 1966 to July 2002 to assess three potential pathways underlying this excess mortality--high human papilloma virus (HPV) prevalence, lack of or infrequent screening and advanced disease at diagnosis, and under-use of recommended treatment and shorter survival. FINDINGS: Living in rural areas may impose barriers to cervical cancer control, including lack of transportation and medical care infrastructures. Population characteristics that place women at greater risk for developing and dying from cervical cancer, such as low income, lack of health insurance, and physician availability, are concentrated in rural areas. Published data, however, are insufficient to identify the key reasons for the observed mortality patterns. CONCLUSIONS: At this time, given the lack of definitive evidence in the published literature, decisions about priorities in areas with high rates of cervical cancer mortality will depend on knowledge of current levels of screening, incidence, and stage distribution; and service delivery infrastructures, resources, and acceptability of interventions to the target population.  相似文献   
83.
Graphene is one of the most promising two-dimensional nanomaterials with broad applications in many fields. However, the variations and fluctuations in the material and geometrical properties are challenging issues that require more concern. In order to quantify uncertainty and analyze the impacts of uncertainty, a stochastic finite element model (SFEM) is proposed to propagate uncertainty for carbon atomic interactions under resonant vibration. Compared with the conventional truss or beam finite element models, both carbon atoms and carbon covalent bonds are considered by introducing plane elements. In addition, the determined values of the material and geometrical parameters are expanded into the related interval ranges with uniform probability density distributions. Based on the SFEM, the uncertainty propagation is performed by the Monte Carlo stochastic sampling process, and the resonant frequencies of graphene are provided by finite element computation. Furthermore, the correlation coefficients of characteristic parameters are computed based on the database of SFEM. The vibration modes of graphene with the extreme geometrical values are also provided and analyzed. According to the computed results, the minimum and maximum values of the first resonant frequency are 0.2131 and 16.894 THz, respectively, and the variance is 2.5899 THz. The proposed SFEM is an effective method to propagate uncertainty and analyze the impacts of uncertainty in the carbon atomic interactions of graphene. The work in this paper provides an important supplement to the atomic interaction modeling in nanomaterials.  相似文献   
84.
African swine fever virus (ASFV) is the etiological agent of African swine fever (ASF), a disease of domestic and wild swine that has spread throughout a large geographical area including Central Europe, East and Southeast Asia, and Southern Africa. Typically, the clinical presentation of the disease in affected swine heavily depends on the virulence of the ASFV strain. Very recently, ASFV was detected in the Dominican Republic (DR) and Haiti, constituting the first diagnosis of ASFV in more than 40 years in the Western hemisphere. In this report, the clinical presentation of the disease in domestic pigs inoculated with an ASFV field strain isolated from samples collected in the DR (ASFV-DR21) was observed. Two groups of domestic pigs were inoculated either intramuscularly (IM) or oronasally (ON) with ASFV-DR21 (104 hemadsorbing dose-50% (HAD50)). A group of naïve pigs (designated as the contact group) was co-housed with the ASFV-DR21 IM-inoculated animals to evaluate ASFV transmission and disease manifestation. Animals inoculated IM with ASFV-DR21 developed an acute disease leading to humane euthanasia at approximately day 7 post-inoculation (pi). Interestingly, animals inoculated via the ON route with ASFV-DR21 developed a heterogeneous pattern of disease kinetics. One animal developed an acute form of the disease and was euthanized on day 7 pi, another animal experienced a protracted presentation of the disease with euthanasia by day 16 pi, and the remaining two animals presented a milder form of the disease, surviving through the 28-day observational period. The contact animals also presented with a heterogenous presentation of the disease. Three of the animals presented protracted but severe forms of the disease being euthanized at days 14, 15 and 21 pi. The other two animals presented with a milder form of the disease, surviving the entire observational period. In general, virus titers in the blood of animals in all study groups closely followed the clinical presentation of the disease, both in length and extent. Importantly, all animals presenting with a prolonged form of the disease, as well as those surviving throughout the observational period, developed a strong ASFV-specific antibody response. These results suggest that ASFV-DR21, unless inoculated parenterally, produces a spectrum of clinical disease, with some animals experiencing an acute fatal form while others presented with a mild transient disease accompanied by the induction of a strong antibody response. At the time of publication, this is the first report characterizing the virulent phenotype of an ASFV field strain isolated from samples collected in the DR during the 2021 outbreak and provides information that may be used in developing epidemiological management measures to control ASF on the island of Hispaniola.  相似文献   
85.
The nonocular manifestations of parenteral drug abuse are presented to familiarize the ophthalmologist with this ever growing, medical and psychosocial problem. The ophthalmologist, like other primary care physicians, may be the first professional to encounter these patients whose substance abuse may lead to a wider spectrum of physical and psychiatric illness. The variety, history, and manifestations of abused substances are discussed.  相似文献   
86.
87.
Retained surgical sponges have been reported to occur after a diversity of surgical procedures, but transmural migration is a very unusual sequela. This article reports a case in which a retained surgical sponge eroded from the intra-abdominal space into the intestinal lumen, migrated distally, and spontaneously passed with defecation 12 weeks after the cesarean section. We performed a systematic review of the literature in Pubmed and found 64 cases of transmural migration of retained surgical sponges. Sixty-four cases have been reported of transmural migration, mainly after intra-abdominal surgery. The most frequent site of impaction is the intestine (75%), but we also found 2 cases that describe migration into the stomach and 7 into the bladder. Five more cases have been published describing transdiaphragmic migration. Only 4 cases describe a sponge spontaneously expelled through the rectum, whereas more than 93% needed re-intervention. We strongly advise only the use sponges with radiopaque markers during surgery and additional methodical wound/body cavity examination.  相似文献   
88.
ObjectivesFew women with ovarian cancer undergo genetic testing for the Breast and Ovarian Cancer susceptibility genes, BRCA1 and BRCA2. With the prospect of BRCA-directed therapeutics, we investigated ovarian cancer patients' knowledge and willingness to undergo genetic testing.MethodsAll ovarian cancer patients seen in the Gynecology Center of a cancer center and a private clinic were asked to complete an anonymous questionnaire regarding knowledge and willingness to undergo BRCA testing. Women who had prior genetic testing were asked not to participate. Data was analyzed using Fisher's exact test.ResultsTwo-hundred and thirty seven ovarian cancer patients voluntarily completed the questionnaire. Fifty-five percent (131/237) of participants had not heard of BRCA testing. Of Caucasian respondents, 51% were unaware of BRCA testing, compared to 70% of Hispanic and 88% of African American respondents (p = 0.008). Awareness was correlated with education (p < 0.001). Eighty-nine percent of participants were willing to be tested if it would directly affect their therapy and 86.9% would be tested to benefit their family. Seventy-four percent of patients would pay 20% of the cost of testing, only 25.1% would pay in full.ConclusionsA majority of women with ovarian cancer are not aware of the availability of BRCA testing. This lack of awareness is more profound in minorities. Despite lack of knowledge, most patients would undergo testing if it would impact their care. However, cost may be a barrier. Given the willingness of patients to undergo testing and the possibility of targeted therapy, clinicians who care for these patients should work to make appropriate genetic counseling referrals.  相似文献   
89.
Developmental Origins Theory has received little coverage in the nursing literature, even though it has received much attention in other sciences. The theory proposes that prenatal stress provokes adaptive changes in endocrine and metabolic processes that become permanently programmed and impact later adult health. This paper reviews the theory and describes the primary neuroendocrine mechanism of hypothalamic-pituitary-adrenal axis function. Supporting research evidence in preterm infant and adult samples is presented. Through knowledge of the theory and the long-term sequelae for preterm infants, nurses will have a different theoretical perspective and growing evidence to consider in their care for pregnant women and infants.  相似文献   
90.
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