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41.
R Hu  C Beck  Y B Chang  L J DeGroot 《Autoimmunity》1992,12(2):103-106
Inheritance of Graves' disease has been linked to the HA-DR3 gene product which may function in some specific way in antigen presentation. To determine whether the first extracellular domain of this protein, which is specifically involved in antigen presentation, has the same sequence in patients with Graves' disease and in normal individuals, we have amplified the second exon using the polymerase chain reaction, and then cloned and sequenced the DNA segment. In eight subjects with Graves' disease, sequences identical to prototypic reported sequence for DRB1*0301 were recovered, and in two individuals sequences varied by a few nucleotides, leading to 1-3 amino acid substitutions which did not occur in a pattern. Sequences identical to the prototypic sequence known as DRB3*0101, also previously known as DRw52, were also recovered. Thus the HLA-DRB1 and B3 genes present in patients with autoimmune disease appear to be the same as those present in the general population. These observations indicate that a unique allele is not present in patients with autoimmune disease, but rather that the normal DR3 allele itself, in a manner yet to be described, increases the probability of developing autoimmune thyroid disease.  相似文献   
42.
Nitric oxide (NO) is a free radical produced by several lung cells via the enzyme nitric oxide synthetase (NOS) and can be easily measured in exhaled air by chemiluminescence analysis. As the iso-enzyme iNOS may be induced by cytokines and endotoxin, NO is elevated in several chronic inflammatory airway diseases. Prior to using exhaled nitric oxide (eNO) as a non-invasive marker of airway inflammation in daily routine, the role of possibly influencing factors such as age, time of the day, smoking exposure and intra-individual variability have to be clarified. NO concentrations were measured in 107 healthy children aged 4–18 years at an expiratory flow of 184 ml/s. Spirometry and a skin-prick test were performed and a questionnaire on family history of atopy, personal symptoms of atopic disease and smoke exposure was completed. For intra-individual variability nitric oxide was measured in six children three times daily on 6 consecutive days. Median eNO concentration was 5.7 p.p.b., and increased significantly with age but did not vary with gender. No correlation was found between eNO and smoke exposure, positive skin-prick test, FEV 1, MEF25 and time of the day. There was no circadian rhythm found in the six children measured on 6 consecutive days, but the eNO showed an intra-individual coefficient of variation of 25.9%. With the help of a two-compartment model of the lung the alveolar NO concentration was estimated to be 4.1 p.p.b and was shown to be constant with age, whereas the airway part of NO steadily increased with age. When comparing eNO values with standardized measurement techniques, the age of the children and the large intra-subject coefficient of variation have to be taken into account, whereas in healthy children subject-specific factors such as atopic history, gender and skin test reactivity did not affect eNO measurement.  相似文献   
43.
Microscopic colitis (MC) encompasses the two morphologically distinct entities of collagenous colitis (CC) and lymphocytic colitis (LC). MC was first described less than 30 years ago but is presently recognized as a relatively common cause of chronic diarrhea in the adult population. Remarkably, up to 10% of adults who have a colonoscopy for the investigation of chronic diarrhea, and have endoscopically normal appearing mucosa, may have MC. Patients with MC generally present with chronic diarrhea, which can be associated with cramping and bloating. Endoscopic and radiological examinations are usually normal. Histological assessment reveals inflammation consisting predominantly of lymphocytic infiltration, and a thickened subepithelial collagen band is diagnostic of CC. Both LC and CC can be associated with autoimmune diseases such as celiac disease, diabetes, arthritis and thyroiditis, yet the mechanisms involved in the pathogenesis remain unclear. Emerging studies suggest that a stepwise approach be taken in the medical management of MC. This approach includes antidiarrheal agents and stopping of any offending agents; budesonide or bismuth subsalicylate; and cholestyramine or 5-acetylsalicylic acid agents. In resistant cases, oral corticosteroids and other immune modulatory therapy have been used.  相似文献   
44.
A dose-escalation study of the calcium ion entry blocking drug nicardipine was performed using large dose infusions in 67 patients with recent aneurysmal subarachnoid hemorrhage (SAH). A safe, potentially therapeutic dose of the drug was determined. Patients admitted within 7 days of SAH from a documented cerebral aneurysm were entered into the study if no spasm was present on the initial angiogram. Nicardipine was administered as a continuous intravenous infusion throughout the 14-day period after SAH, regardless of the timing of surgery. To determine the safest possible dose, nicardipine was administered at seven dose levels from 0.01 to 0.15 mg/kg/hr. The total daily doses ranged from 27.7 mg to 375.0 mg. A follow-up angiogram was carried out on all 67 patients 7 to 10 days after SAH. Computerized tomography and neurological examinations were used to determine the presence of cerebral infarction. No major adverse effects, unexpected reactions, or permanent sequelae could be attributed to nicardipine. A decline in blood pressure was noted following administration of the drug. This occurred more frequently among patients given the largest dose but did not produce clinical problems or require discontinuation of the drug. Favorable outcomes were noted in 52 patients (78%). Vasospasm was found by arteriography in 31 patients (46%). A dose-related trend was noted: only eight (24%) of 33 patients treated at the highest dose level (approximately 10 mg/hr) developed arteriographic evidence of vasospasm. Symptomatic vasospasm was diagnosed in only two (6%) of 33 patients treated with this dose. Of the 34 patients receiving the lower dose levels, angiographic spasm was observed in 68% and symptomatic vasospasm in 27%. No deaths due to vasospasm occurred. Nicardipine appears to prevent both vasospasm and cerebral ischemia after SAH. A multicenter randomized double-blind trial to test this hypothesis is planned.  相似文献   
45.
Principal components analyses of the Beck Self-Concept Test (BST) were conducted independently for 288 women with primary mood disorders, 230 women with anxiety disorders, 236 men with mood disorders, and 161 men with anxiety disorders. Four self-concept dimensions that reflected (1) Intellectual Ability; (2) Work Efficacy; (3) Physical Attractiveness; and (4) Virtues/Vices occurred within the four samples. For 5-item subscales that represent these four dimensions, a two-way MANOVA found significant effects for sex and type of disorder. Women described themselves as having less intellectual ability than men did. Outpatients with mood disorders considered their physical appearance, work efficacy, and virtues/vices to be less acceptable than did those with anxiety disorders. Findings were discussed with respect to the cognitive content-specificity theory of psychopathology.  相似文献   
46.
47.
Background: Intraoperative awareness in patients undergoing general anesthesia is an infrequent but well-described adverse outcome. The reported incidence of this phenomenon is between 0.1% and 0.9%.

Methods: With institutional review board approval, the authors reviewed continuous quality improvement data from 3 yr (2002-2004) at the locations where the physician group provided anesthesia. Board-certified anesthesiologists supervising certified registered nurse anesthetists in the anesthesia care team model of practice delivered all anesthetics. Brain function monitors were not used in the operating room setting. Patients were interviewed twice during a 48-h postoperative period and, as part of that process, underwent a modified Brice interview to determine intraoperative awareness. All cases that met the criteria for awareness were examined by the continuous quality improvement committee to modify anesthetic practice and were included in this study.

Results: Data from 211,842 patients undergoing anesthesia were considered. Of these, the continuous quality improvement process followed up 177,468 (83.1%). Cases were not included in the study if the patient was younger than 18 yr, did not have a general anesthetic, or had a terminal event during the hospital course. By these criteria, a total of 87,361 patients followed by the continuous quality improvement process were at risk for awareness. Six patients reported instances of recall.  相似文献   

48.
49.
In the study, skeletal status was evaluated in 2850 females aged 7 to 77 yr using quantitative ultrasound (QUS amplitude-dependent speed of sound [Ad-SoS]). Ad-SoS ranged from 1923 +/- 30 to 1876 +/- 81 m/s, and the peak value (2121 m/s) was achieved in 19-yr-old females. Ad-SoS increased significantly between subgroups aged 11 and 12 yr, 12 and 13 yr, 13 and 14 yr, 14 and 15 yr, and 15 and 16 yr. After the age of 19 yr the only significant drop was noted between age groups 47 and 48 yr. Ad-SoS was regressed on age, weight, and height for age ranges 7 to 11 yr.(before an increase in Ad-SoS), 12 to 19 yr (from the onset of the increase to the peak value), and older than 19 yr to menopause. In females after menopause, years since menopause (YSM) were taken into consideration. In the two youngest groups Ad-SoS was affected positively by age, and in the two next groups, age had a negative influence on Ad-SoS, whereas weight had a negative and height a positive influence in all groups. YSM did not influence the Ad-SoS value. It was concluded that QUS measurements at the hand phalanges are a useful tool in assessment of skeletal status in the female population.  相似文献   
50.
Avian influenza (AI) and Newcastle disease (ND) viruses are heat labile viruses, but exact parameters for heat inactivation at egg pasteurization temperatures have not been established. In this study we artificially infected four egg products with two AI (one low [LP] and one high pathogenicity [HP]) and three ND (two low and one highly virulent) viruses, and determined inactivation curves at 55, 57, 59, 61 and 63 degrees C. Based on D(t) values, the time to inactivation of the viruses was dependent on virus strain and egg product, and was directly related to virus titre, but inversely related to temperature. For all temperatures, the five viruses had the most rapid and complete inactivation in 10% salt yolk, while the most resistant to inactivation was HPAI virus in dried egg white. This study demonstrated that the LPAI and all ND viruses were inactivated in all egg products when treated using industry standard pasteurization protocols. By contrast, the HPAI virus was inactivated in liquid egg products but not in dried egg whites when using the low-temperature industry pasteurization protocol.  相似文献   
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