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101.
Eleven cases of MS occurred within a 10-year period in a zinc-related manufacturing plant. The observed disease incidence was greater than expected from population data, using multiple approaches to statistical analysis (p less than or equal to 0.01). A case-control study, performed to examine several zinc parameters in blood, failed to indicate specific abnormalities among the MS patients, but all subjects (both MS and controls) working in the plant demonstrated higher serum zinc levels than all subjects (MS and controls) not working there. 相似文献
102.
Jacquie A Shillis Beverly A Hall Gail G Sneden Nell H Gottlieb 《Health education & behavior》2003,30(6):771-788
This case study examines a nonlegislative task force as it struggled to reach internal consensus despite external political constraints. The study highlights the convergence of politics and science, revealing complex issues likely to be confronted by advocates and public health officials. Three themes capture participants' experiences: context, sizing up the opportunities and constraints; task force process, tacit strategy to operate outside the political context and play the science card; and aftermath, a glass half full. The task force took advantage of ambiguous parameters, crafting a comprehensive statewide plan to reduce tobacco use and breaking out of the common public health paradigm of allowing budget considerations to drive program design. These internal victories could not sustain a policy success in the legislature. However, the group's product sets science-based standards for future program development, and the task force's process provides valuable insights into other states developing tobacco prevention and control policies. 相似文献
103.
D K Benjamin R Schelonka R White H P Holley E Bifano J Cummings K Adcock D Kaufman B Puppala P Riedel B Hall J White C M Cotton 《Journal of perinatology》2006,26(5):290-295
OBJECTIVES: Very low birth weight (VLBW) infants are vulnerable to nosocomial infections and subsequent morbidity; including infections caused by Staphylococcus aureus: 85% of nosocomial S. aureus infections are caused by capsular polysaccharide (CPS) types 5 and 8. Altastaph is a polyclonal investigational human immunoglobulin G (IgG) with high levels of opsonizing S. aureus CPS types 5 and 8 IgG. METHODS: A Phase 2 clinical trial to assess the safety and kinetics of Altastaph in VLBW infants. Neonates in this multicenter study were randomized to receive two identical 20 ml/kg i.v. infusions of either 0.45% NaCl placebo or 1000 mg Altastaph/kg. Each infant was followed for 28 days after the second infusion or until discharge. Serum S. aureus CPS types 5 and 8 IgG levels were measured preinfusion and at various times after each infusion. RESULTS: Of 206 neonates, 158 received both infusions. Adverse events were similar in the two treatment groups. Six subjects (3% in each group) discontinued owing to an adverse event. Geometric mean anti-type 5 IgG levels were 402 and 642 mcg/ml 1 day following infusion of the first (day 0) and Second (day 14) doses, respectively, in neonates < or =1000 g and slightly higher in neonates 1001 to 1500 g. Trough levels before second infusion were 188 mcg/ml. Type 8 IgG levels were similar. Geometric mean IgG levels among placebo recipients were consistently <2 and <5 mcg/ml for types 5 and 8 in both weight groups. Three episodes of S. aureus bacteremia occurred in each arm. CONCLUSIONS: Infusion of Altastaph in VLBW neonates resulted in high levels of specific S. aureus types 5 and 8 CPS IgG. The administration of this anti-staphylococcal hyperimmune globulin was well tolerated in this population. 相似文献
104.
Remotely-controlled approach for stereotactic neurobiopsy. 总被引:1,自引:0,他引:1
The objective of this study was to develop, demonstrate, and validate a remotely controlled operation scheme coupled with prospective magnetic resonance imaging (MRI)-based stereotaxy for in vivo neurosurgical applications. The novel concept of the prospective guidance scheme is to employ tomographical imaging feedback, such as MRI or CT, to facilitate prospectively the targeting process of a biopsy needle at near-real-time speed (1 image/s). Because the orientation of a biopsy needle pivoted at an entry point on the patient's skull has 2 degrees of freedom, the alignment of its trajectory to a target point can be guided by two-dimensional (2D) images whose plane is placed perpendicular to the desired trajectory. Using near-real-time 2D visual feedback during the adjustment of the alignment guide, the required trajectory alignment can be translated into a simple targeting task on a computer monitor employing a suitable graphic presentation. Also, both adjustments for the alignment and introduction of the biopsy needle were accomplished remotely with image-based feedback. The use of the method in actual MR-guided brain lesion biopsy procedures at 1.5 T showed an improved tissue yield due to the improved targeting accuracy even in the presence of brain shift. Furthermore, the postalignment trajectory can be validated immediately using near-real-time MRI scans in two orthogonal views before needle insertion. Because the final needle position is always visualized and confirmed, the consequent tissue sampling is performed with greater certainty, even in the case of a negative diagnosis. The actual targeting error was 1.53 +/- 0.17 mm from an intended target location, with the maximum distance error of 1.72 mm at a depth of 85 mm. This remotely controlled surgical approach with intraoperative MRI guidance is feasible at 1.5 T, and has allowed neurosurgeons to perform neurobiopsies comfortably and efficiently in a routine clinical MR scanner. This scheme provides a unique alternative stereotactic procedure that can take full advantage of the prospective guidance potential offered by various modern tomographic imaging systems. 相似文献
105.
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107.
The periodontal disease syndromes present the practitioner with an extensive array of clinical conditions. However, by performing a careful examination and recording of findings, the clinician will provide order to this seemingly complex picture. This careful and reasoned approach is based on a logical sequence starting with clinical observations that lead to a diagnosis of the disease entity present. This correct diagnosis in turn will lead to establishment of the prognosis and the therapeutic approach. By following these precepts, the practitioner ensures a sound biologic basis for his or her efforts. The end result is the realization of the goal of dental therapy that her is for the patient to maintain dentition in health, comfort, and function for a lifetime and minimize the potential for urgent periodontal needs. 相似文献
108.
The effects of functional endoscopic sinus surgery (FESS) on sinus and midfacial development remain unclear. The authors report five children who, at a median age of 30 months, underwent FESS for refractory sinusitis. Three of the children had cystic fibrosis, and two had asthma. Preoperative computed tomographic (CT) scanning showed symmetric maxillary sinus development with varying degrees of mucosal disease. At a mean of 42 months after surgery, CT scans were obtained to evaluate recurrent symptoms in the five children. The scans showed unilateral maxillary hypoplasia in four children and bilateral maxillary sinus hypoplasia in one child. No child had clinically apparent facial asymmetry or midfacial hypoplasia. The authors also discuss the factors involved in maxillary sinus pneumatization, the possible effects of sinus surgery on sinus development, and the clinical implications of “acquired” maxillary sinus hypoplasia. Laryngoscope, 106:1210-1213, 1996 相似文献
109.
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