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101.
Endotoxin-adsorbing fibers have been applied to treat septic shock patients. The limitations of endotoxin hemoadsorption therapy (PMX-DHP) and the optimal time to start PMX-DHP were examined in patients with septic multiple organ failure with hypercytokinemia (interleukin-6 = 1000 pg/mL). Subjects were separated into those who survived more than 28 days after the start of PMX-DHP therapy (S group) and those who did not (N-S group). Severity of symptoms and background factors, blood biochemical parameters, hemodynamic parameters, PaO(2)/FiO(2), pathogens, endotoxin, cytokines, and vascular endothelial cell function-related markers were examined before and after PMX-DHP. Number of days from onset of shock (or symptom development) to PMX-DHP initiation was longer in the N-S group than in the S group. These results suggest that PMX-DHP could save more lives in patients with septic multiple organ failure with IL-6 = 1000 pg/mL when applied early after the onset of shock.  相似文献   
102.
Dissociation of retinal ganglion cells without enzymes   总被引:1,自引:0,他引:1  
We describe here methods for dissociating retinal ganglion cells from adult goldfish and rat without proteolytic enzymes, and show responses of ganglion cells isolated this way to step-wise voltage changes and fluctuating current injections. Taking advantage of the laminar organization of vertebrate retinas, photoreceptors and other cells were lifted away from the distal side of freshly isolated goldfish retinas, after contact with pieces of membrane filter. Likewise, cells were sliced away from the distal side of freshly isolated rat retinas, after these adhered to a membrane filter. The remaining portions of retina were incubated in an enzyme-free, low Ca2+ solution, and triturated. After aliquots of the resulting cell suspension were plated, ganglion cells could be identified by dye retrogradely transported via the optic nerve. These cells showed no obvious morphological degeneration for several days of culture. Perforated-patch whole-cell recordings showed that the goldfish ganglion cells spike tonically in response to depolarizing constant current injections, that these spikes are temporally precise in response to fluctuating current injections, and that the largest voltage-gated Na+ currents of these cells were larger than those of ganglion cells isolated with a neutral protease.  相似文献   
103.
Lactoferrin (LF) is known as an iron-binding glycoprotein. It has been shown that bovine LF (bLF) is transported into cerebrospinal fluid via blood although its physiological effects in the central nervous system (CNS) are still unclear. In this study, a suppressive effect of bLF on psychological distress was investigated in adult rats. Intraperitoneal injection of bLF (100 mg/kg) reduced stressful behaviors in a conditioned fear-induced freezing test and an elevated plus-maze test. Interestingly, the suppressive effect of bLF was enhanced by pretreatment with electric foot-shock (FS). This suppressive effect of bLF in the elevated plus-maze test was reversed by pretreatment with naloxone, an opioid receptor antagonist, at a dose of 1 mg/kg (ip). N(omega)-nitro-l-arginine methyl ester (l-NAME), a nitric oxide synthase (NOS) inhibitor, also blocked the suppressive effect of bLF and foot-shock. In addition, combined application of a low dose of bLF (30 mg/kg, ip) and l-arginine (30 and 100 mg/kg, ip) showed significant potentiated effects on psychological stress. These results suggest that bLF has suppressive effects on psychological distress, especially under the condition of moderate stress. Furthermore, it is suggested that bLF possibly activates an endogenous opioidergic system via nitric oxide synthase activation.  相似文献   
104.
The mechanochemical reaction of free riboflavin (FR) due to vibratory ball milling was carried out in a stainless steel vessel at room temperature under anaerobic conditions. The ESR of the fractured sample showed a broad single-line spectrum. It is suggested that the solid-state single-electron transfer (SSET) reaction from the surface of the stainless steel vessel to FR proceeded during the vibratory milling, resulting in the formation of the corresponding anion radicals. When the mechanochemical reaction of FR in the presence of calcium pantothenate (PC) was carried out, the radical concentration increased with the increasing PC content. It was shown that the anion radical in the metal complex was stable for a lengthy period of time even in highly humid air.  相似文献   
105.
OBJECTIVES: This study examined the association of resource use with comorbidity status and patient age among hip fracture patients who underwent surgical treatment. DESIGN: We used a database from the Voluntary Hospitals of Japan Quality Indicator Project that involved 10 privately owned leading teaching hospitals in Japan. SETTING: Four of these hospitals in Japan. PARTICIPANTS: We selected 778 operable hip fracture patients aged 65 or older who were admitted to these hospitals between January 1996 and August 2000 (mean age: 80.3 +/- 7.3 years). MEASUREMENTS: A linear mixed model was performed to identify factors associated with the resource use, such as total length of stay (LOS), LOS before surgery, LOS after surgery, total hospital charges, charges for diagnostic examinations, charges for surgery, and length of theater time, among operable hip fracture patients. RESULTS: The mean LOS was 45.9 days, and the mean total hospital charges were US dollars 14,495.0. Results from linear mixed models revealed that higher age was significantly associated with shorter length of theater time (P < 0.01), and that the presence of comorbidity among hip fracture patients was significantly associated with longer total LOS (P < 0.01), longer LOS after surgery (P < 0.001), higher charges for diagnostic examinations (P < 0.001), and shorter length of theater time (P < 0.01). CONCLUSION: These results suggest that the presence of comorbidity among operable hip fracture patients requires greater resource use during their hospital stay, but higher age is not significantly associated with greater resource use at all.  相似文献   
106.
OBJECTIVES: The involvement of tightly insulated housing conditions and passive smoking in atopic sensitization, a major risk factor for airway allergy, was examined with nonsmoking adult women and school-age children. SUBJECTS AND METHODS: The subjects were 382 nonsmoking healthy adult women (housewives) who underwent medical examinations for prevention of adult diseases conducted in a district of Osaka from 1995 to 1997, and 214 elementary school-children 9-12 years old living in an urban district of Osaka who underwent medical examinations at a health center in April, 2000 to prevent allergic diseases. We also examined the correlation between tightly insulated housing conditions and the amount of passive smoking based on family smoking habits with 170 children under 12 years old who had been under the care of a hospital pediatrics department between December, 1993 and May, 1994. A questionnaire was administered to all subjects to survey the housing structure (concrete/wooden housing), family smoking habits and visible mold proliferation in the kitchen in relation to airtight housing conditions, passive smoking and exposure to inhalant allergens. Atopic sensitization was assessed by positivity for serum house dust mite-specific IgE, and passive smoking was defined as a urinary cotinine level of more than 6 ng/mgCr. RESULTS: 1. Among the three factors, indoor mold proliferation and family smoking habits were positively and synergistically related with atopic sensitization to house dust mites. 2. Airtight conditions of concrete housing showed a promotional effect on passive smoking for housewives, but a suppressive effect for school-age children. 3. Taking into account the above results, the promotional effects of passive smoking on atopic sensitization appeared predominantly in the concrete housing-residence group of housewives and the wooden housing-residence group of school-age children. 4. Effects of visible mold proliferation in the kitchen on atopic sensitization appeared predominantly in wooden housing-residence group of housewives. CONCLUSIONS: The results suggest that involvement of the three factors in atopic sensitization is due to increased exposure to indoor inhalant allergens or enhanced IgE-antibody production (adjuvant effects of tobacco smoke) and the extent of their inpact varies depending on the individual life styles of the housewives and school-age children.  相似文献   
107.
Nosocomial infection is regarded as a serious problem whose incidence and complexity has been increasing, thus generating various types of social and economic implications. This investigation aimed at assessing the incidence of surgical site infection and risk factors in patients submitted to elective surgeries in the specialty of gastroenterology performed in a public hospital in the interior of S?o Paulo State. Data were collected by means of a retrospective study of medical records from January to December 1999. Of the 134 cases under study, the occurrence of surgery site infection was detected in 18 situations (13.4%). Nine cases (50%) were considered to be superficial incisional infections, 8 (44.4%) were deep incisional infections and 1 (5.5%) was an organ/space infection. With respect to the risk factors, the ones with percentage higher or equal to 50% were: age above 50 years, the presence of neoplasia, surgeries that last more than two hours and inadequate trichotomy.  相似文献   
108.
109.
BACKGROUND AND PURPOSE: Whether misery perfusion (MP) commonly accompanies brain borderzones (BZs) in patients with major cerebral artery occlusion remains unclear. We elucidated topographic patterns of chronic hemodynamic failure in such patients. METHODS: Twenty-four patients with unilateral occlusion or severe stenosis (>75% in diameter) of the internal carotid artery (ICA) or middle cerebral arterial (MCA) trunk with minimal or no infarct underwent PET with (15)O-labeled gas inhalation. Mean cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral metabolic rate of oxygen, oxygen extraction fraction (OEF), and CBV/CBF ratio were determined in the superficial BZs, internal BZ, and MCA territory excluding BZs. Values in BZs were standardized and compared with those in controls. Topographic distributions of regions with OEF greater than that in controls were determined. RESULTS: Values in patients and controls were not significantly different. Topographic distributions included matched perfusion in 10 patients, MP in only the ipsilateral internal BZ in four, MP in both ipsilateral internal and superficial BZs in two, MP in the ipsilateral MCA territory including BZs in one, MP in the ipsilateral MCA territory including BZs and contralateral BZs in two, and MP in the ipsilateral MCA territories including BZs in five. CONCLUSION: Only 25% of the patients had MP localized in affected BZs Although localized MP more frequently accompanied the internal BZ than other regions, no patient had elevated OEF in the superficial BZ alone. These results are inconsistent with clinical observations that 80% of BZ infarctions develop superficially. Thus, hemodynamic mechanisms may not cause most superficial BZ infarctions.  相似文献   
110.
This article contains reflections concerning infection prevention and control measures starting from the adherence of health professionals to prevention measures. It points out worrisome environment-related aspects stemming from the use of disposable materials in spite of the benefits that they represent in terms of safety and reduction of operational costs, among others. All these issues are presented as a challenge to infection control teaching in the education of health professionals. Some guiding presuppositions are also presented.  相似文献   
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