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31.
We studied 42 patients undergoing oral surgery under local anaesthesia with i.v. sedation, allocated randomly to receive either methohexitone (group M) or propofol (group P) for patient-controlled sedation (PCS). Group M patients self-administered 2.5-mg (0.5 ml) bolus doses of methohexitone and group P, 5-mg (0.5 ml) doses of propofol, without a lockout. The 0.5-ml bolus dose was delivered over 7.2 s for both drugs. The procedure was completed satisfactorily in all patients. Patients in both groups achieved their desired levels of sedation. No patient lost verbal contact. Group M patients had higher heart rates during the procedure. The lowest SpO2 values recorded were 92% and 95% for group P and group M, respectively. Immediately after operation patients in group M reported that they felt more sleepy than those in group P (P < 0.01) but there were no differences at subsequent times. The results of the psychomotor tests were comparable for the two groups after operation, except for the "posting box task" at 15 min after operation when the mean decrement (compared with preoperative performance) was - 3% for group P and -13% for group M (P < 0.05). More patients in group P complained of pain in their hand. We conclude that methohexitone is a suitable alternative drug to propofol for PCS.   相似文献   
32.
We have studied the influence of grass pollen immunotherapy on cellular infiltration and cytokine mRNA expression during allergen-induced late-phase cutaneous responses. In a double-blind, placebo-controlled trial of immunotherapy in 40 adult hay fever sufferers, clinical improvement was accompanied by a decrease in the size of the late-phase skin response. When the immunotherapy-treated group was compared with the placebo group, analysis of skin biopsies obtained 24 h after intradermal allergen revealed a significant reduction in the number of infiltrating CD3+ (P = 0.04) and CD4+ (P = 0.009) cells and a trend for a decrease in EG2+ eosinophils (P = 0.08). Treatment did not influence allergen-induced recruitment of CD8+ cells, neutrophils, or macrophages. Unexpected increases in expression of CD25 (P = 0.006) and HLA-DR (P = 0.007) were observed in the actively treated group. In situ hybridization using a panel of riboprobes demonstrated "TH2-type" (IL-4, IL-5) cytokine mRNA responses in both groups of patients. In contrast, significant hybridization for IL-2 (8/16 patients, P = 0.02) and for interferon-gamma (6/16 patients, P = 0.04) was observed only in the actively treated group. These findings indicate that immunotherapy is associated with suppression of allergen-induced CD4+ T lymphocyte infiltration, but among the cells that are recruited, there is upregulation of CD25 and HLA-DR. At least in this model, immunotherapy does not appear to affect expression of TH2-pattern cytokines in response to allergen exposure, but expression of mRNA for Th1-type cytokines was enhanced in half of the patients. The results support the view that immunotherapy may possibly be working through induction of T cell tolerance.  相似文献   
33.
The clinical features of 78 patients with SLE seen in Cairo and Glasgow are reviewed. Raynaud's phenomenon was recorded more frequently here than in previous series. The value of serial measurements of anti-DNA antibodies, C3 and C4 in the management of SLE is discussed. Although antibodies to native DNA paralleled the disease course in only a minority of SLE patients anti-DNA antibodies were present during all major SLE exacerbations and could be diagnostically useful. Serious systemic infections complicating the management of SLE patients could occur and their diagnosis is discussed.  相似文献   
34.
Standardization of rotational chair testing across laboratories has not been achieved because of differences in test protocol and analysis algorithms. The Interlaboratory Rotational Chair Study Group was formed to investigate these differences. Its first study demonstrated significant variability in calculated results using actual patient data files. No estimation of accuracy could be made, however, because the "true" values of response parameters were unknown. In this study we used simulated "patient" data files to further explore the differences among analysis algorithms. We found a high degree of agreement and accuracy across laboratories using automated analysis of high signal-to-noise/low-artifact data for gain, phase, and asymmetry. Variability increased significantly for the lower signal-to-noise ratio/higher artifact files. Operator intervention generally improved accuracy and decreased variability, but there were cases in which operator intervention reduced accuracy.  相似文献   
35.
Objectives: Th-2 type cytokine production (inter-leukin-4 [IL-4] and interleukin-5 [IL-5]) has been demonstrated to play a significant role in the pathophysiology of allergic rhinitis (AR), and the treatment of AR with topical corticosteroids has been shown to reduce the expression of Th-2 type cytokines in vivo. However, the contribution and expression of Th-2 type cytokine receptors in AR and their response to corticosteroid treatment remain to be clarified. Objectives of the current study are 1. To examine the expression of the cytokine IL-4 and IL-5 receptors (IL-4R and IL-5R) in a nasal allergen challenge model and to contrast this with the expression of the receptor for the Th-1 type cytokine, interferon-gamma receptor (IFN-γR), and 2. to examine the effects of pretreatment with topical corticosteroid before allergen challenge on the expression of these same receptors. Study Design: Randomized prospective study involving 14 ragweed-allergic subjects evenly divided between placebo and corticosteroid pretreatment. Methods: Immunocytochemistry (alkaline phosphatase-antial-kaline phosphatase labeling [APAAP] technique) was used to stain nasal biopsy specimens before and after allergen challenge. Antibodies used included anti-CD3, CD4, CD8, MBP, IL-4R, IL-5R, and IFN-γR. Results: Following allergen challenge, we observed a significant increase in the Th-2 type cytokine receptors (IL-4R and IL-5R; P < .05), as well as a significant decrease in the expression of the Th-1 type cytokine receptor (IFN-γR; P < .05). Pretreatment with topical corticosteroids before nasal allergen challenge resulted in decreased expression of IL-4R (P < .05) and IL-5R (P < .05) and increased expression of IFN-γR (P < .05). Further, IL-4R and IL-5R expression correlated with eosinophil infiltration in the tissues. Conclusions: We have demonstrated that in AR, cytokine receptors for IL-4, IL-5, and IFN-γ follow a similar pattern to their ligands. In addition, pretreatment with topical corticosteroids was shown to alter the cytokine receptor expression pattern from a Th-2 profile more toward a Th-1 profile. Laryngoscope, 108:1528–1533,1998  相似文献   
36.
In neonates, bilirubin tends to be deposited in body tissues, especially the skin and mucous membranes. Jaundice is an early symptom of bilirubin excretion disorders. Therefore, the aim of this study was to investigate the effect of clofibrate on reducing neonatal jaundice. In this systematic review, international databases, including PubMed, Scopus, Web of Science, Embase, Cochrane, and Google Scholar, were searched without time and language restrictions. The reference lists of all studies ultimately included were manually searched. In the 17 articles reviewed, with a sample size of 665 people published between 2005 and 2019, the average weight of the neonates varied from 2,186 g to 4,000 g. Furthermore, the average age of neonates varied from 2 days to 9 days. Four doses of clofibrate (25, 30, 50, 100 mg/kg of neonatal body weight) were used. The bilirubin level of neonates significantly decreased in the intervention group 24, 36, 48, and 72 hours after the start of treatment. Clofibrate administration decreased total serum bilirubin, especially from the second day onwards, and also reduced hospitalization time, hospital costs, and side effects from hospitalization.  相似文献   
37.
AIM OF THE STUDY: Contraceptive plants which were introduced by folk in traditional remedies are investigated worldwide. In this study, the contraceptive effects of Ruta graveolens L., which has been mentioned for male contraceptive in Iranian traditional folk medicine, was experimented on human sperm. MATERIALS AND METHODS: Different doses of lyophilized aqueous extract of Ruta graveolens L. were added to an amount of fresh semen, containing 10(6) cells in a 1:1 volumic ratio. Motility and viability of cells, DNA status, mitochondrial activity and sperm revival tests were carried out. RESULTS: The sperm immobilization effects of the extract appeared immediately in a does-dependent manner and 100% of the sperms became immotile at a concentration of 100mg/ml but other parameters were intact. After washing the sperms, motility was returned in 30.8+/-3.2% of the sperms, besides coiled tails in 38.6+/-5.5% of the treated cells, in comparison to 12.5+/-2.0% of the control group (p=0.001). The part of the extract, responsible for immobilization of the sperms was stable upon boiling. CONCLUSIONS: As the cells were alive and immotile, probably some ionic currents are blocked by a thermostable component of the plant which can be promising as a new male channel blocker contraceptive.  相似文献   
38.
In the present work, we provide a comprehensive numerical investigation of the magnetic properties and phase spectra of three types of spin-1/2 branched chains consisting of one, two and three side spins per unit block with intra-chain interaction and a uniform inter-chain interaction in the presence of an external magnetic field. In a specific magnetic field interval, the low-temperature magnetization of these chains shows a step-like behavior with a pronounced plateau depending on the strength and the type of intra-chain interaction being ferromagnetic or antiferromagnetic. We demonstrate that when inter-chain interaction J1 is antiferromagnetic and intra-chain interaction J2 is ferromagnetic, the magnetization of the models manifests a smooth increase without a plateau, which is evidence of the existence of a Luttinger-like spin liquid phase before reaching its saturation value. On the other hand, when J1 is ferromagnetic and J2 is antiferromagnetic, the low-temperature magnetization of the chain with two branches shows an intermediate plateau at one-half of the saturation magnetization that breaks a quantum spin liquid phase into two regions. The magnetization of the chain with three branches exhibits two intermediate plateaus and two regions of a quantum spin liquid. We demonstrate that the chains with more than one side spin illustrate in their ground-state phase diagram a Kosterlitz–Thouless transition from a gapful phase to a gapless spin liquid phase.  相似文献   
39.
Dietary intervention is generally accepted as the mainstay of treatment for patients with disorders of amino acid metabolism (AAMDs). However, dietary adherence to a low-protein diet is always reported as a common challenge among these patients. This study explored the perception of barriers and motivators to dietary adherence among caregivers of AAMD patients in Malaysia. Twenty caregivers of children with AAMDs receiving ongoing treatment at the genetic clinic participated in an online focus group discussion from November to December 2021. Findings showed a total of five interrelated main themes identified from focus group discussion (FGD) exploring parents’ experiences related to the management of their child’s daily diet. The barriers to dietary adherence were burden of dietary treatment, diet and dietary behavior, parenting challenges, limited knowledge related to dietary treatment, and challenges in healthcare system delivery. Key factors facilitating good dietary adherence include good knowledge of dietary treatment, parental coping strategies, social coping, and dietary behavior. In conclusion, despite the existence of several barriers to the implementation of dietary treatment, caregivers managed to use a wide range of coping strategies to overcome some, if not all, of the challenges. The important next step is to develop, in conjunction with multidisciplinary healthcare professionals, feasible implementation strategies that could address these barriers and at the same time improve the quality of life of caregivers.  相似文献   
40.
Moyamoya disease is an unusual occlusive cerebrovascular condition commonly seen in children, marked by stenosis of the internal carotid artery and circle of Willis, causing, cerebral ischemia. Moyamoya syndrome is a Moyamoya-like arteriopathy with risk factors including autoimmune disorders, thyroid disease, sickle cell disease, or Down syndrome. Trisomy 21 is a genetic disorder consistent with specific physical and behavioral characteristics, with intellectual impairment. We describe a rare case of Moyamoya syndrome manifesting as ischemic stroke in an adult with Down syndrome  相似文献   
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