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121.
In newborns, large amounts of heat are lost from the head, due to its high skin surface area. Insulating the head (for example, with a hat or bonnet) can be a simple and effective method of reducing dry heat loss. In the present study, we evaluated the safety aspects of insulating the head of low-birth-weight naked or clothed newborns by using a heated mannequin that simulates a low-birth-weight newborn. Experimental conditions (comprising a nude and three clothed setups) were performed in a closed incubator at three different air temperatures (29 degrees C, 32 degrees C, and 34 degrees C) and with and without the head being covered with a bonnet in each case, i.e., 24 experimental conditions in all. The study shows that added clothing elements and insulating the head decreases the total heat loss of the mannequin as a whole. As regards the dry heat exchange from the head, wearing a bonnet decreases the local heat loss by an average of 18.9% in all clothed and thermal conditions. This phenomenon could be at the origin of brain overheating in heavily dressed newborns, when unrestricted heat loss is limited to the face only. Our results suggest that--apart from accidental hypothermia-in order to achieve thermal equilibrium of the body, it is preferable to leave the head unprotected and to increase the level of clothing insulation over the rest of the body. 相似文献
122.
Antibiotic therapy of intensive care patients is usually undocumented. The treatment is chosen according to epidemiologic and susceptibility data from microbiological laboratories. The aim of our study is to determine antibiotic susceptibility of enterobacteria isolated from intensive care patients during a five-month multicenter study in 18 French hospitals. Numerous (n = 1,113) strains were studied: 447 enterobacteria isolated from urine (n = 229), blood cultures (n = 106), respiratory tract specimens (n = 72), peritoneal fluids (n = 22), pus (n = 15) and catheters (n = 2). MICs of group 2 and group 3 enterobacteria were determined using the dilution agar method and were interpreted according to the CASFM (Comité de l'antibiogramme de la société fran?aise de microbiology) recommendations. Group 1 enterobacteria were most frequently isolated (67%). Only one Escherichia coli strain produced ESBL (0.3%). Among group 2 enterobacteria, one Citrobacter koseri strain produced ESBL. We did not isolate Klebsiella pneumoniae ESBL. Isolation of group 3 enterobacteria was frequent (24%). Thirty-five percent of group 3 enterobacteria were resistant to cefotaxime, 26% to ceftazidime and 16% to cefepime and cefpirome. Fourteen strains of this group produced ESBL: 13 Enterobacter aerogenes and one E. amnigenus. 相似文献
123.
BACKGROUND/AIMS: The accuracy and reliability of any method to assess the UVA protection effectiveness of sunscreens needs to be demonstrated. The aim of the present study was to calibrate the effectiveness of a biological end point (Persistent Pigment Darkening, PPD) to assess UVA photoprotection, METHODS: Persistent Pigment Darkening was selected as the end point because its action spectrum extends across the UVA. A broad UVA source was chosen to challenge all UVA wavelengths. Attenuation of UVA was performed with neutral density filters (equally absorbing at all wavelengths). Human subjects were tested with a series of UVA beams attenuated by the neutral density filters. The UVA protection effectiveness of a standard sunscreen was also tested with four panels of volunteers to assess the reproducibility of the method. RESULTS: The attenuation factors of the neutral density filters were found to correspond to the UVA protection factors arrived at with PPD as the end point. The repetitive tests showed a good internal consistency of the method. CONCLUSIONS: The calibration procedure proposed shows threshold PPD, used as an end point in a UVA-PF test method, to be a reliable endogenous dosimeter for UVA radiation that enters the skin. 相似文献
124.
高效液相色谱法测定寒痹停片中士的宁含量 总被引:6,自引:0,他引:6
目的:建立用HPLC测定寒痹停片中士的含量的方法。方法:氰基柱;流动相-甲醇-水-三乙胺-乙酸(9800:155:15:30);紫外检测波长254nm。结果:在4~20ug/ml范围内,标准曲线回归方程为:Y=-2803+8967x(r=0.9997),RSD=1.65%?加样回收率的平均值为99.82%。结论:实验表明,这是一个适用于生产控制和产品质量检验的简单、快速、准确的方法。 相似文献
125.
BDSS Budagoda KAS Kodikara WKS Kularatne RM Mudiyanse DH Edussuriya JP Edirisinghe IP Karunaratne KGAD Weerakoon SC Medagedara SAM Kularatne 《Asian Pacific journal of tropical medicine》2010,3(7):586-588
The sting of Giant Asian honeybee (Apis dorsata) or Bambara in Sinhala and Karunge Kulavi in Tamil is a common environmental hazard in Sri Lanka known to cause immediate allergic reactions, which could be fatal in sensitized individuals. We reported myocardial infarction, bowel gangrene and fatal anaphylaxis in a prospectively proven case series and the association of these uncommon complications with delayed removal of stingers from the patients' skin. 相似文献
126.
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128.
A group of 228 consecutive patients undergoing metrizamide myelography was prospectively evaluated for postprocedure symptoms. The observed prevalence of these symptoms concurs with previously reported inpatient studies, with the most common sequelae being exacerbation or onset of spine or extremity pain, headache, nausea, and paresthesia. Limitation of administered dose of metrizamide in lumbar myelography may slightly reduce the occurrence of common symptoms, but withdrawal of contrast medium at the completion of examination had no impact on their occurrence. There was a higher occurrence of paresthesia in cervical myelography, but otherwise there was no significant difference in symptoms between cervical and lumbar studies. Outpatient metrizamide myelography can be performed with relative safety with the potential for significant cost savings. 相似文献
129.
Policies which tend to reduce surgical stress and therefore decrease catabolism and to improve anabolism could allow patients to recover more quickly and efficiently even after major surgery. In most instances, interruption of nutritional intake is not necessary after surgery. Oral intake can be started as soon as possible within the first 24 hours unless surgical contra-indication. Oral intake should be adjusted according to patient's tolerance. In patients without overt under-nutrition, postoperative nutritional support for periods of less than 7 days is not indicated. However, nutritional support is recommended when postoperative food intakes reach less than 60% of daily needs for 7 days. Moreover, early nutritional support should probably be administered if expected postoperative food intake will be less than 60% of daily needs for more than 7 days. In malnourished patients, nutritional support (using enteral rather than parenteral route) is strongly recommended within the first postoperative 24 hours regardless of preoperative nutritional support. 相似文献
130.