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91.
Summaey We report the development of a new subdural probe for combined intracranial pressure (ICP) and cerebral blood flow (CBF) monitoring with near infrared spectroscopy (NIRS) and indocyanine green (ICG) dye dilution. For NIRS a conventional subdural ICP monitoring probe was supplied with two fiber bundles and 90-degree prisms. Injections of 25mg ICG were performed. Regional values for the mean transit time of ICG (rmttICG), cerebral blood flow (rCBF) and cerebral blood volume (rCBV) were calculated. With prototypes of the probe in two patients with intracerebral haemorrhage 18 comparative measurements obtained simultaneously with conventional NIRS (optodes placed on the skin) and the subdural NIRS probe were performed. The new subdural NIRS probe allows combined monitoring of ICP and cerebral hemodynamics in the brain directly, without the influence of extracerebral tissue. 相似文献
92.
Selective accumulation of ALA-induced PpIX and photodynamic effect in chemically induced hepatocellular carcinoma 总被引:3,自引:0,他引:3
Otake M Nishiwaki M Kobayashi Y Baba S Kohno E Kawasaki T Fujise Y Nakamura H 《British journal of cancer》2003,89(4):730-736
The possibility of 5-aminolaevulinic acid-based photodynamic therapy (ALA-PDT) for liver cancer was investigated using a chemically induced hepatocellular carcinoma (HCC) model. Endogenously synthesised protoporphyrin IX (PpIX) following the administration of ALA is an effective photosensitiser for PDT. We determined the fluorescence intensity of PpIX in HCC and nontumoral tissue in the liver. 5-Aminolaevulinic acid was intravenously injected to male Fisher rats with HCC at a dose of 500 mg x kg(-1), and the fluorescence intensity in each tissue sample excised from liver was measured with a spectrofluorometer at 1, 3 and 6 h after administration. Fluorescence intensity was at a peak of 3 h after administration in both HCC and nontumoral tissue. The accumulation of PpIX in HCC was higher than that in the nontumoral tissue at 1 h (P<0.001) and 3 h (P<0.05) after ALA administration. Based on these results, PDT was performed on HCC at 3 h after 500 mg x kg(-1) ALA administration before laser irradiation of 30 J per tumour. Antitumour effect was more evident in HCC than in the nontumoral tissue surrounding HCC. These findings suggest the possibility to detect HCC by fluorescence and to treat HCC by light. 相似文献
93.
AIM: The aim of this study was to investigate the influence of hydration in voids along root fillings on methylene blue penetration. METHODOLOGY: A total of 80 human root canals were prepared using a step-back technique and filled with a zinc oxide based sealer and gutta-percha. Leakage along the fillings was measured by a transport fluid model and classified into three categories: gross leakage (GL), slight leakage (SL) and no leakage (NL). Specimens with NL and SL were immersed into methylene blue (MB) 2% for 24 h (group I). Specimens with GL which had wide gaps filled with water were randomly divided into two groups (II, III). Transport air was applied to remove water from gaps only in specimens of group III. All tested specimens from groups II and III were also immersed into MB 2% for 24 h. Each specimen was then split longitudinally and linear measurements of dye penetration were recorded. RESULTS: Group III (with dry gaps) showed significantly more dye penetration than group II. No significant difference was found between group I and group II. CONCLUSIONS: Methylene blue penetrates along root fillings more easily in dry gaps than in water-filled gaps. 相似文献
94.
Wallace JF Pugia MJ Lott JA Luke KE Shihabi ZK Sheehan M Bucksa JM 《Journal of clinical laboratory analysis》2001,15(5):231-235
The goal of our study was to perform a multisite evaluation of a new urine dipstick called Multistix PROtrade mark (Bayer, Elkhart, IN), which has reagent pads for the simultaneous assay of urinary albumin, protein, and creatinine. Patients' urine specimens were assayed at four sites with these dipsticks and with the familiar Bayer Multistix 10SG dipsticks for protein. The new dipstick pads for albumin are impregnated with bis (3',3"-diiodo-4',4"-dihydroxy-5',5"-dinitrophenyl)-3,4,5,6-tetrabromo-sulfonephthalein (DIDNTB) dye. These dipsticks also have a novel pad that estimates urinary creatinine using the peroxidase activity of the copper-creatinine complex. We determined the interlaboratory agreement of these dipsticks by comparing dipstick results to values obtained by quantitative analytical methods. We found that dividing the dipsticks' albumin or protein results by the creatinine concentration reduced the number of false-positive albumin or protein values observed in concentrated urines, and reduced the number of false negatives in dilute urines. The ratio of albumin to creatinine, or protein to creatinine gives a better measure of albumin or protein excretion. Compared to reading by eye, the dipstick results agreed better with the quantitative assays when they were read by a reflectometer (Bayer Clinitek). 相似文献
95.
Background: Sentinel node biopsy (SNB) for breast cancer patients is a new technique with the potential to provide an accurate staging of the axillary nodal status while avoiding the morbidity of an axillary dissection. The objective of the present study is to validate the use of sentinel node biopsy in a New Zealand hospital and to compare the ability of patent blue dye (PB) alone with triple modality (TM) (preoperative lymphoscintigraphy, intraoperative gamma probe and intraoperative blue dye) to identify the sentinel node. Methods: A total of 104 patients who had a palpable breast lump that was confirmed to be malignant by radiology and cytology and a clinical diagnosis of stage I or stage II breast cancer, were enrolled for SNB and randomly assigned to triple modality or blue dye alone for the localization of the sentinel node. Axillary dissection was performed after the sentinel node(s) had been removed. Results: There were 63 patients in the PB group and 41 patients in the TM group. Both groups are comparable, with a similar mean age and primary tumour size. A sentinel node was identified in 57 (90%) of the PB group patients and 40 (98%) of the TM group patients. Of these 23 (37%) of the PB group and 23 (56%) in the TM group had axillary nodes positive for malignancy. There was one false negative SNB in the PB group and two false negative results in the TM group. Therefore, the PB group had an accuracy of 98% and a sensitivity of 96% compared to an accuracy of 95% and a sensitivity of 91% for the TM group. Conclusion: The results of the present study validate the use of SNB in suitable breast cancer patients. Identification and the accuracy of the sentinel node localization were similar between the two groups. Therefore, in hospital centres without adequate access to a nuclear medical facility, it would be feasible to conduct SNB using blue dye alone. 相似文献
96.
We investigated strategies involved in odour intensity coding by the primary olfactory centre of insects, the antennal lobe (AL), the structural and functional analogue of the olfactory bulb. Using calcium imaging in the honeybee, we simultaneously measured the projection neuron output responses and a compound signal dominated by receptor neuron input in identified olfactory glomeruli to odours spanning seven log units of concentration. A comparison of the two processing levels indicates that the intercellular computation within the AL modulates and contrast-enhances the primary olfactory signals. As a result the AL network optimizes the olfactory code: odour representation is improved at lower concentrations, the relative activity of olfactory glomeruli allows encoding odour quality over up to four log-unit concentrations, and odour-intensity is reliably represented in the overall excitation across AL. 相似文献
97.
Role of skin prick test and serological measurement of specific IgE in the diagnosis of occupational asthma resulting from exposure to vinyl sulphone reactive dyes 总被引:1,自引:1,他引:0 下载免费PDF全文
Park JW Kim CW Kim KS Choi SY Kang DB Ko SH Won JU Yang JY Hong CS 《Occupational and environmental medicine》2001,58(6):411-416
OBJECTIVES—Some patients with occupational asthma resulting from exposure to reactive dyes have skin reactivity to the causative dyes and specific IgE to reactive dyes have been found in these patients. However, the usefulness of skin prick tests (SPTs) and serological measurement of specific IgE in screening, diagnosis, and monitoring the occupational asthma resulting from exposure to reactive dyes have not yet been assessed. In this study, the clinical validation of SPTs and measurement of specific IgE to vinyl sulphone reactive dyes by enzyme linked immunosorbent assay (ELISA) was evaluated.
METHODS— 42 Patients with occupational asthma from reactive dyes (true positive group) were enrolled. In these the causative reactive dye was confirmed by bronchial challenge test. 93 Asymptomatic factory workers with negative challenge to the reactive dye (true negative group) and 16 unexposed controls with negative challenge to the reactive dye were also enrolled. Skin prick tests were done with 10 mg/ml reactive dye in 0.4% phenol/0.9% saline. IgE specific to reactive dye conjugated to human serum albumin (HSA) was measured with enzyme linked immunosorbent assays (ELISAs).
RESULTS—None of the unexposed controls had a positive response to SPTs. The sensitivity (76.2% v 53.7%), specificity (91.4% v 86.0%), positive predictive value (80.0% v 62.9%), and negative predictive value (89.5% v 80.8%) of SPTs were higher than those of ELISAs. The mean weal size of reaction to reactive dye was weakly correlated with the ELISA optical density of IgE to reactive dye conjugate in patients with occupational asthma from reactive dyes (n=41, r=0.337, p<0.05). In four patients with occupational asthma from reactive dyes and eight control subjects exposed to reactive dye, IgE specific to reactive dye conjugated to HSA was detected with ELISA even though they showed negative skin reactivity. Six patients completely avoided the reactive dye for a mean (SD) 27.8 (10.3) months, IgE specific to reactive dyes decreased in all six patients (p<0.05) during this time.
CONCLUSIONS—Both SPTs and detection of IgE specific to reactive dye in serum samples could be valuable for screening, diagnosis, and monitoring occupational asthma resulting from exposure to reactive dyes. These two tests would complement each other.
Keywords: reactive dye; occupational asthma; skin prick test 相似文献
METHODS— 42 Patients with occupational asthma from reactive dyes (true positive group) were enrolled. In these the causative reactive dye was confirmed by bronchial challenge test. 93 Asymptomatic factory workers with negative challenge to the reactive dye (true negative group) and 16 unexposed controls with negative challenge to the reactive dye were also enrolled. Skin prick tests were done with 10 mg/ml reactive dye in 0.4% phenol/0.9% saline. IgE specific to reactive dye conjugated to human serum albumin (HSA) was measured with enzyme linked immunosorbent assays (ELISAs).
RESULTS—None of the unexposed controls had a positive response to SPTs. The sensitivity (76.2% v 53.7%), specificity (91.4% v 86.0%), positive predictive value (80.0% v 62.9%), and negative predictive value (89.5% v 80.8%) of SPTs were higher than those of ELISAs. The mean weal size of reaction to reactive dye was weakly correlated with the ELISA optical density of IgE to reactive dye conjugate in patients with occupational asthma from reactive dyes (n=41, r=0.337, p<0.05). In four patients with occupational asthma from reactive dyes and eight control subjects exposed to reactive dye, IgE specific to reactive dye conjugated to HSA was detected with ELISA even though they showed negative skin reactivity. Six patients completely avoided the reactive dye for a mean (SD) 27.8 (10.3) months, IgE specific to reactive dyes decreased in all six patients (p<0.05) during this time.
CONCLUSIONS—Both SPTs and detection of IgE specific to reactive dye in serum samples could be valuable for screening, diagnosis, and monitoring occupational asthma resulting from exposure to reactive dyes. These two tests would complement each other.
Keywords: reactive dye; occupational asthma; skin prick test 相似文献
98.
Methylene blue dye as an alternative to isosulfan blue dye for sentinel lymph node localization 总被引:4,自引:0,他引:4
Abstract: Isosulfan blue dye has been used with increasing frequency in localizing sentinel lymph nodes in breast cancer patients. Few alternative types of dye have been investigated. In a prospective study of 30 patients, methylene blue dye was used instead of isosulfan blue dye to localize the sentinel lymph node. The methylene blue dye localization technique was successful in 90% of patients. These results are similar to those for isosulfan blue dye. This study describes methylene blue dye localization as a successful alternative to isosulfan dye in identifying the sentinel node in breast cancer patients. The methylene blue dye technique offers a substantial cost reduction. 相似文献
99.
BACKGROUND AND OBJECTIVE: Xanthelasma palpebrarum presents a therapeutic and aesthetic challenge because of its high visibility and frequent rate of recurrence with a wide variety of treatments. Many patients are disappointed by an initial unsuccessful treatment and fail to return for further therapy until the skin problem has become quite conspicuous. A simple treatment with few side effects and good acceptance remains an important goal. STUDY DESIGN/MATERIALS AND METHODS: Fifteen patients with a total of 33 xanthelasma lesions, were treated by an erbium:YAG laser. The follow-up period of observation was between seven and twelve months. RESULTS: All lesions were removed without hyperpigmentation or scarring. CONCLUSIONS: The erbium:YAG laser represents an effective means for treating xanthelasmas with few side effects. 相似文献
100.
染发类化妆品中染发剂的使用情况分析 总被引:1,自引:0,他引:1
目的:研究染发类化妆品中染发剂的使用情况。方法:统计分析2003~2005年290份国产和进口染发类化妆品中染发剂的使用种类、频率和用量。结果:290份样品共使用39种染发剂,其中间苯二酚、对苯二胺(及硫酸盐)、对氨基酚、间氨基酚(及盐酸盐)、2,5-二氨基甲苯(及硫酸盐)的使用频率较高,均在30%以上。结论:染发类化妆品中染发剂的使用种类繁多,某些组分使用频率较高,在使用中应引起关注。 相似文献