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排序方式: 共有1096条查询结果,搜索用时 109 毫秒
1.
M S Abdel-Rahman G A Skowronski R M Turkall S E Gerges A H Abu-Hadeed A M Kadry 《Drug and chemical toxicology》1987,10(3-4):257-274
Alcide Allay, an antimicrobial preparation produced in gel and liquid forms, was evaluated for vaginal toxicity in guinea pigs. 1.0 g/kg Allay gel or placebo was administered intravaginally once per day over a 30 day period while 2.5 g/kg Allay liquid (containing either of two concentrations of sodium chlorite and lactic acid as active ingredients) or placebo was applied vaginally three times per day for 10 days. At the conclusion of the studies, hematology, blood and urine clinical chemistry tests and necropsies were performed. RBC, HGB, HCT, MCHC and direct bilirubin increased while CO2, SGPT and CPK decreased in blood after Allay liquid treatment. Creatinine, urea nitrogen and uric acid in urine were statistically reduced in the liquid groups. Hematology and clinical chemistry parameters were within the normal range of values reported in the literature for guinea pigs, indicating no clinical significance due to drug treatment. Significant differences in organ body/weight ratios were observed between controls and Allay gel and liquid groups. However, only the livers in the gel study and the vaginas in both studies were changed histologically. 相似文献
2.
Andrzej Nowakowski Lukasz Kubaszewski Przemys?aw Nawrot 《Chirurgia narzadów ruchu i ortopedia polska》2007,72(5):357-361
The most difficult in proper qualification of the patient with chronic low back pain for an operative treatment is determination of the chance for satisfactory result. The diversity of the pain eliciting structure in the spine influence the decision. In the paper we have analyzed patient where the operative treatment was considered. In 149 patients divided in two groups the (not being previously operated on the spine--group 1 and after spine surgery--group 2) the neuroradiological procedures were performed (sacral epidural block, facet injections, root injections of the lumbar spine). As the result of this procedure in 108 patients (72%) surgical intervention at that time was abandoned. Conclusion. In our opinion the neuroradiological diagnostic procedures should be mandatory in back pain management of the patient were operative treatment is considered. We present the modified algorithm in diagnostic procedure preceding the operation. 相似文献
3.
4.
Immunization with a combination of merozoite surface proteins 4/5 and 1 enhances protection against lethal challenge with Plasmodium yoelii 总被引:2,自引:0,他引:2 下载免费PDF全文
Kedzierski L Black CG Goschnick MW Stowers AW Coppel RL 《Infection and immunity》2002,70(12):6606-6613
It is widely believed that subunit vaccines composed of multiple components will offer greater protection against challenge by malaria, and yet there is little experimental evidence to support this view. We set out to test this proposition in the Plasmodium yoelii challenge system in rodents by comparing the degree of protection conferred by immunization with a mixture of merozoite surface proteins to that conferred by single proteins. We therefore examined a defined protein mixture made of the epidermal growth factor-like domains of P. yoelli merozoite surface protein 1 (MSP1) and MSP4/5, the homologue of P. falciparum MSP4 and MSP5. In the present study we demonstrate that this combination of recombinant proteins dramatically enhances protection against lethal malaria challenge compared to either protein administered alone. Many mice immunized with the MSP4/5 plus MSP1(19) combination did not develop detectable parasitemia after challenge. Combined immunization with MSP1(19) and yMSP4/5, a product characterized by lower protective efficacy, also greatly enhanced protection by reducing peak parasitemias and increasing the numbers of survivors. In some combination trials, levels of antibodies to MSP1(19) were elevated compared to the MSP1(19) alone group; however, improved protection occurred regardless of whether boosting of the anti-MSP1(19) response was observed. Boosting of anti-MSP1(19) did not appear to be due to contaminating endotoxin in the EcMSP4/5 material since enhanced protection was observed in C3H/HeJ mice, which are endotoxin insensitive. Collectively, these experiments show that multiantigen combinations offer enhanced levels of protection against asexual stage infection and suggest that combinations of MSP1, MSP4, and MSP5 should be evaluated further for use in humans. 相似文献
5.
T cells with high-affinity T cell receptors (TCRs) for a foreign peptide-major histocompatibility complex (pMHC) appear to be negatively selected, even though they have never seen the foreign antigen. To examine how this process operates, we used in vitro yeast display to isolate high-affinity TCRs from the T cell clone 2C. The TCRs showed fast on-rates, which were consistent with reduced CDR (complementarity determining region) flexibility, and cross-reactivity with other cognate pMHCs. T cell hybridomas transfected with a high-affinity TCR were stimulated by endogenous self-pMHC, which suggested that T cells bearing the TCR would be negatively selected. The immune system appears to maintain a repertoire of flexible, low-affinity TCRs at the expense of more effective high-affinity TCRs. 相似文献
6.
Struzik L Duffin J Vermani M Hegadoren K Katzman MA 《Respiratory physiology & neurobiology》2002,133(3):183-195
Klein (Arch. Gen. Psychiatry 50, 306-317, 1993) suggests that panic attacks are the result of a defective 'suffocation alarm' threshold that presents with carbon dioxide (CO(2)) hypersensitivity, exaggerated ventilatory response and panic in panic disorder (PD) patients. Serotonergic deficiencies enhance this ventilatory response in PD patients, as per 'suffocation alarm' theory predictions, suggesting that serotonin (5-HT) normalizes the ventilatory response. Other research supports a serotonin system-mediated stimulation of ventilation. Knowledge of 5-HT's role on ventilatory output and its neurophysiological sources impacts on the 'suffocation alarm' theory validity and predictive value. We used tryptophan depletion (TRP-) in concert with a modified Read rebreathing test to determine the effect of deficient serotonergic modulation on the central and peripheral chemoreflex threshold and sensitivity of response to CO(2) in 11 healthy men. TRP- did not affect central or peripheral chemoreflex threshold or sensitivity of response to CO(2). However, basal ventilation was significantly elevated during TRP-. In contrast to 'suffocation alarm' theory predictions, decreased 5-HT neurotransmission does not significantly affect the respiratory chemoreflex response to CO(2), impacting on non-chemoreflex drives to breathe. Panic associated respiratory abnormalities may be related to defective 5-HT modulation of non-chemoreflex drives to breathe, unrelated to any respiratory chemoreflex abnormality. 相似文献
7.
Dam J Guan R Natarajan K Dimasi N Chlewicki LK Kranz DM Schuck P Margulies DH Mariuzza RA 《Nature immunology》2003,4(12):1213-1222
The Ly49 family of natural killer (NK) receptors regulates NK cell function by sensing major histocompatibility complex (MHC) class I. Ly49 receptors show complex patterns of MHC class I cross-reactivity and, in certain cases, peptide selectivity. To investigate whether specificity differences result from topological differences in MHC class I engagement, we determined the structure of the peptide-selective receptor Ly49C in complex with H-2K(b). The Ly49C homodimer binds two MHC class I molecules in symmetrical way, a mode distinct from that of Ly49A, which binds MHC class I asymmetrically. Ly49C does not directly contact the MHC-bound peptide. In addition, MHC crosslinking by Ly49C was demonstrated in solution. We propose a dynamic model for Ly49-MHC class I interactions involving conformational changes in the receptor, whereby variations in Ly49 dimerization mediate different MHC-binding modes. 相似文献
8.
P-glycoprotein expression influences the result of 99mTc-MIBI scintigraphy in tertiary hyperparathyroidism 总被引:2,自引:0,他引:2
Chudzinski W Niderla J Lasiecka Z Wilczynski G Gornicka B Wasiutynski A Maczewska J Kobylecka M Krolicki L Durlik M Nowacka E Lazarczyk M Dziunycz P Milewski L Nawrot I Grzela T 《International journal of molecular medicine》2005,16(2):215-219
Precise localization of parathyroid glands using 99mTc-labeled hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) scintigraphy could be affected by various biological factors. There is increasing evidence that radiotracer retention could be controlled by members of multidrug resistance (MDR) system, especially P-glycoprotein (P-gp). Since the role of P-gp in tertiary hyperparathyroidism (T-HPTH) scintigraphic studies is poorly recognized, the aim of the study was to compare the correlation between parathyroid P-gp expression and results of their scintigraphy in T-HPTH versus primary hyperparathyroidism (P-HPTH). P-HPTH (n = 19) and T-HPTH (n = 18) patients were subjected to 99mTc-MIBI scintigraphy followed by surgical treatment. The parathyroid glands were assessed in routine hematoxylin-eosin staining and P-gp expression was analyzed using immunohistochemistry. Parathyroids collected during cadaver donor multi-organ harvesting were used as a control. It has been found that P-HPTH-derived parathyroid glands with predominating adenoma morphology expressed less P-gp, as compared to P-gp-rich T-HPTH glands, mainly displaying nodular or diffused hyperplasia phenotype. This finding reversely correlated with results of 99mTc-MIBI scintigraphy. However, we did not observe any difference in P-gp expression nor scintigraphy result between nodular or diffused hyperplasia. Altogether, these data suggest that P-gp overexpression in T-HPTH could be responsible for decreased sensitivity of 99mTc-MIBI scintigraphy in those patients. Therefore, the recently proposed reduced neck exploration or limited parathyroid resection on the basis of scintigraphy could create the risk of persisted/recurrent hyperparathyroidism. However, this problem requires further study. 相似文献
9.
Treatment of severe cardiogenic pulmonary edema with continuous positive airway pressure delivered by face mask 总被引:39,自引:0,他引:39
A D Bersten A W Holt A E Vedig G A Skowronski C J Baggoley 《The New England journal of medicine》1991,325(26):1825-1830
BACKGROUND. Severe cardiogenic pulmonary edema is a frequent cause of respiratory failure, and many patients with this condition require endotracheal intubation and mechanical ventilation. We investigated whether continuous positive airway pressure delivered by means of a face mask had physiologic benefit and would reduce the need for intubation and mechanical ventilation. METHODS. We randomly assigned 39 consecutive patients with respiratory failure due to severe cardiogenic pulmonary edema to receive either oxygen alone or oxygen plus continuous positive airway pressure delivered through a face mask. It was not possible to blind the investigators to the assigned treatment. Physiologic measurements were made over the subsequent 24 hours, and the patients were followed to hospital discharge. RESULTS. After 30 minutes, both respiratory rate and arterial carbon dioxide tension had decreased more in the patients who received oxygen plus continuous positive airway pressure. The mean (+/- SD) respiratory rate at 30 minutes decreased from 32 +/- 6 to 33 +/- 9 breaths per minute in the patients receiving oxygen alone and from 35 +/- 8 to 27 +/- 6 breaths per minute in those receiving oxygen plus continuous positive airway pressure (P = 0.008); the arterial carbon dioxide tension decreased from 64 +/- 17 to 62 +/- 14 mm Hg in those receiving oxygen alone and from 58 +/- 8 to 46 +/- 4 mm Hg in those receiving oxygen plus continuous positive airway pressure (P less than 0.001). The patients receiving continuous positive airway pressure also had a greater increase in the arterial pH (oxygen alone, from 7.15 +/- 0.11 to 7.18 +/- 0.18; oxygen plus continuous positive airway pressure, from 7.18 +/- 0.08 to 7.28 +/- 0.06; P less than 0.001) and in the ratio of arterial oxygen tension to the fraction of inspired oxygen (oxygen alone, from 136 +/- 44 to 126 +/- 47; oxygen plus continuous positive airway pressure, from 138 +/- 32 to 206 +/- 126; P = 0.01). After 24 hours, however, there were no significant differences between the two treatment groups in any of these respiratory indexes. Seven (35 percent) of the patients who received oxygen alone but none who received oxygen plus continuous positive airway pressure required intubation and mechanical ventilation (P = 0.005). However, no significant difference was found in in-hospital mortality (oxygen alone, 4 of 20 patients; oxygen plus continuous positive airway pressure, 2 of 19; P = 0.36) or the length of the hospital stay. CONCLUSIONS. Continuous positive airway pressure delivered by face mask in patients with severe cardiogenic pulmonary edema can result in early physiologic improvement and reduce the need for intubation and mechanical ventilation. This short-term study could not establish whether continuous positive airway pressure has any long-term benefit or whether a larger study would have shown a difference in mortality between the treatment groups. 相似文献
10.
Adriana Mika Lukasz P Halinski Tomasz Sledzinski Sylwia Malgorzewicz Paulina Woloszyk Jolanta Dardzinska Alicja Debska-Slizien Michal Chmielewski 《Nutrients》2021,13(3)
Patients with end-stage kidney disease, treated with renal transplantation, are at increased risk of cardio-vascular disease (CVD) and cardio-vascular mortality. They are also characterized by an atherogenic dyslipidemia. Alterations of the fatty acids (FA) profile contribute to increased cardio-vascular risk in the general population. In the current study we test the hypothesis that kidney transplantation is associated with ab-normalities in FA profile. FA profile was analysed by gas chromatography–mass spectrometry in 198 renal transplant recipients, and 48 control subjects. The most profound differences between renal transplant patients and controls were related to the content of branched chain FA, monounsaturated FA, and n-6 polyunsaturated FA, respectively. The FA profile significantly separated the patients from the controls in the principal component analysis (PCA). The abnormalities of FA profile showed a tendency for normalization in long-term kidney recipients, as compared to patients with recent transplants. The n-3 PUFA content demonstrated a strong inverse association with the presence of inflammation. Most profound alterations of the FA profile were observed in patients with impaired graft function (glomerular filtration rate < 45 mL/min). The study demonstrated significant disorders of the FA profile in kidney transplant recipients, that might contribute to cardio-vascular risk in this vulnerable patient population. 相似文献