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991.
Type and duration of fetal asphyxial insult affect the distribution of blood flow to the heart and brain. The purpose of this study was to describe dynamic and quantitative changes in regional myocardial and cerebral blood flow (CBF) during fetal asphyxia induced by total occlusion of the umbilical cord. Eleven exteriorized fetal sheep were subjected to total umbilical cord occlusion and five fetal sheep served as sham controls. Regional blood flow (BF) to the brain and heart was quantified using radioactive microspheres before and after 5 min of occlusion and finally when fetal mean arterial blood pressure had decreased below 25 mm Hg, 9.8 (0.8) [mean (SD)] min after occlusion. Right coronary arterial (RCA) blood flow velocity and carotid BF were registered continuously. Mean values of arterial pH and oxygen content (mL O(2)/100 mL) were 7.08 (0.11) and 4.4 (2.9) before cord occlusion and decreased to 6.83 (0.05) and 1.4 (0.9) at 5 min after occlusion (p < 0.01, respectively). Carotid BF was significantly below preocclusion values by 2.5 min (p < 0.05), whereas RCA velocity time integral per minute remained above preocclusion values for 9 min. CBF decreased from 316 (24) before cord occlusion to 156 (30) mL/min/100 g at 5 min (p < 0.01), whereas right myocardial BF was maintained at 792 (125) and 751 (183) mL/min/100 g, respectively. CBF decreased rapidly after total cord occlusion whereas myocardial BF increased and was maintained until shortly before cardiac arrest, suggesting the myocardium to be better preserved during this type of insult in already partially asphyxiated fetuses.  相似文献   
992.
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994.
Because of changes in legislation, dialysis may now be performed in all hospitals in The Netherlands, which could affect the quality of the therapy. Therefore a system of quality management in health care, and especially in dialysis, was developed. In this article the implementation and evaluation of such a system is described.  相似文献   
995.
A case of a bullous eruption occurred in a patient being treated with penicillamine for sclerodermatous graft-versus-host disease following bone marrow transplantation. After 7 days of treatment with 150 mg penicillamine, a painful bullous eruption with accompanying purpuric lesions suddenly developed in previous sclerodermatous infiltrations. A diagnosis of epidermolysis bullosa acquisita-like eruption was made, and the patient was treated with drug withdrawal and administration of cyclosporine and methylprednisolone. Epidermolysis bullosa acquisita-like reaction is an extremely rare cutaneous side effect of penicillamine. The surprisingly early onset of this eruption in lesions of sclerodermatous graft-versus-host disease might have been due to severe immune alteration.  相似文献   
996.
Hofmann A  Plachy J  Hunt L  Kaufman J  Hala K 《Vaccine》2003,21(32):4694-4699
B(12) haplotype of the inbred chicken line CB (B12/B12) contains, like the bulk of chicken MHC(B) haplotypes, only a single dominantly expressed class I molecule (B-F). The peptide binding motifs for this major B-F12 molecule in chickens of Rous sarcoma regressor line CB (B12/B12) have been determined. Using stringent and relaxed motifs, several peptides were found in the v-src molecule of the PR-RSV-C, but most of these peptides are identical with that of endogenous c-src. Only the v-src C-tail peptide(517-524) (LPACVLEV) contains critical anchor amino acids (valine at positions 5 and 8) and shows a sequence different from the corresponding c-src peptide. This v-src C-tail peptide up-regulates expression of the B-F12 class I molecule on PBL, as assessed by FACS analysis, and stimulates T cell proliferation in a [3H]thymidine uptake assay. A protective effect of the immune response to LPACVLEV against RSV challenge was demonstrated in CB (B12/B12) chickens immunised with peptides encapsulated in liposomes.  相似文献   
997.
The uterus is innervated by adrenergic sympathetic fibres, and the endometrium has a capability for endogenous monoamine synthesis. Extracellular monoamine levels are regulated primarily through re-uptake by specific membrane-bound transporter proteins dopamine transporter (DAT), norepinephrine transporter (NET) and serotonin transporter (SERT). Intracellular storage of monoamines involves vesicular transporter proteins (VMAT1 and VMAT2). This study explored gene expression of the monoamine transporters in normal endometrium throughout the menstrual cycle and early decidua. In-situ hybridization histochemistry revealed three general classes of expression patterns: (i). epithelial expression of NET mRNA; (ii). increasing stromal expression of VMAT2 mRNA in the proliferative phase; and (iii). increasing epithelial expression of VMAT2 mRNA during the secretory phase. Real time PCR showed low expression levels of NET in all phases of the endometrial cycle and a higher expression of VMAT2 mRNA in the mid-secretory phase. Our results suggest that several monoamine transporters may have menstrual cycle phase-specific functions in endometrial biology by maintaining adequate levels of monoamines. Re-uptake and regulated release of monoamines may also modulate several steps of the reproductive processes such as embryo implantation and decidua formation.  相似文献   
998.
OBJECTIVE: Galectin-3 is an endogenous lectin that reacts with glycan epitopes of membrane and extracellular glycoproteins, including integrins, fibronectin, laminin and tetraspanins. Its expression, and also the presentation of its glycoligands, is controlled in a differentiation-dependent manner in squamous epithelia. The aim of this study was to monitor the carbohydrate-dependent binding of labeled galectin-3 to primary head and neck squamous cell carcinomas (from the tonsil, base of the tongue and larynx) and lymph node metastases. MATERIAL AND METHODS: Double labeling (using antibodies against desmoplakin-1, Ki-67 and cytokeratins) at the single-cell level was employed to cytologically characterize cells reacting with galectin-3. RESULTS: Galectin-3 binds a non-proliferating pool of tumor cells. Colocalization of galectin-3 binding sites with desmosomal proteins may indicate a role for this endogenous lectin in the formation of intercellular contacts of the desmosomal type. Cytokeratin-10-positive tumor cells also presented galectin-3-reactive binding sites on the surface; however, cytokeratin-10-free cells were also recognized by this lectin. CONCLUSION: These findings intimate that galectin-3 may represent a new tool for monitoring the degree of cell differentiation in carcinomas originating from the transformation of squamous cell epithelia.  相似文献   
999.
Prevention of biofilm formation in dialysis water treatment systems   总被引:3,自引:0,他引:3  
BACKGROUND: Biofilm formations in dialysis systems may be relevant because they continuously release bacterial compounds and are resistant against disinfection. The aim of the study was to compare the development of biofilm between a water treatment system based on a single reverse osmosis unit producing purified dialysate water [bacterial count, 350 colony-forming unit (CFU)/L] (center A) and a water treatment system based on double reverse osmosis and electric deionization, which is continuously disinfected with ultraviolet light and treated with ozone once a week (bacterial count, 1 CFU/L) (center B). METHODS: During a period of 12 weeks, biofilm formation was studied in the tubing segment between the water piping and the dialysis module, using four dialysis monitors in each center. On a weekly basis, tubing samples of 5 cm length (N = 96) were taken under aseptic conditions and investigated for microbiologic contamination [cystine lactose electrolyte-deficient (CLED) Agar], endotoxin levels [limulus amoeben lysate (LAL) gel test, cutoff value, 0.0125 EU/mL], and biofilm formation [electron scanning microscopy (SEM)]. RESULTS: In center A, tube cultures were positive (>100 CFU/mL) in 16% of samples at 22 degrees C and 37 degrees C, compared to 3% of samples of center B (P < 0.05; chi-square). Endotoxin levels were positive in 76% of the tubing samples of center A and negative in all of the samples of center B (P < 0.05). Biofilm was present in 91.7% of the samples of center A (Fig. 1), and only present in one sample (taken after 9 weeks) of center B (P < 0.05) (Fig. 2). In center A, biofilm formation was already observed after 1 week. CONCLUSION: In contrast to a standard water treatment system producing purified water, the use of a system producing highly purified water, which is also treated with regular disinfection procedures, leads to a significant reduction in biofilm formation, bacterial growth, and endotoxin levels in a highly vulnerable part of a water treatment system.  相似文献   
1000.
Recent studies have shown that nitric oxide molecule may have a role in the development of cataract. In this study, we measured the levels of a nitric oxide metabolite (nitrite) in the cataractous and normal human lenses. A modified Griess assay was used to determine the nitrite levels in the lenses as a measure of nitric oxide, based on the spectrophotometric method. Nitrite was detected in 26 (44.1%) cataractous lenses and was found below the detection limit in 33 (55.9%) cataractous lenses. Mean nitrite levels in cataractous lenses (2.77+/-5.26nmol/100mg) was found higher than the normal lenses (0.77+/-0.79nmol/100mg) but this increase was not statistically significant. Comparison of nitrite levels among lenses with various types of cataracts revealed higher levels in lenses with posterior subcapsular cataracts. Hypertensive patients had also significantly higher nitrite levels in their cataractous lenses. The increased levels in the cataractous lenses display a possible role of nitric oxide in the pathogenesis of cataract in human eyes.  相似文献   
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