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11.
Two kindreds with the multiple endocrine neoplasia type 2A syndrome were studied. Of one of these we examined 150 members, 20 of whom were treated with thyroidectomy for medullary carcinoma and nine with bilateral adrenalectomy for pheochromocytoma. Of the second kindred 59 members were examined, seven of whom were thyroidectomized and seven treated with bilateral adrenalectomy. Pheochromocytomas were invariably found on both sides, even in four cases in which the adrenals on one side appeared to be completely normal, not only at preoperative roentgenologic examination but also on inspection during the operation. The microscopic finding of micronodules and a cluster of abnormal medullary cells identical with those found in pheochromocytomas in one of the apparently normal adrenals represents a first stage in the development of diffuse medullary hyperplasia as well as nodular hyperplasia. This is in accordance with the fact that in the MEN type 2A syndrome pheochromocytomas are always multicentric and multiple in origin. On the basis of these findings we conclude that all patients with the MEN 2A syndrome who show symptoms and signs of active pheochromocytoma should be subjected to bilateral adrenalectomy, even when one or both of the adrenals appear to be normal at roentgenologic investigation.  相似文献   
12.
Temporal arteritis (TA), or giant cell arteritis, is a systemic autoimmune vasculitis affecting patients over 50 years of age. It can cause rapid, irreversible bilateral vision loss in older adults and is therefore considered an ophthalmological emergency. Many of the symptoms and signs of TA can be vague, non-specific and gradual in onset, often leading to a delayed or inaccurate diagnosis. As such, it is important for a wide variety of primary optometrists and health practitioners to maintain a robust understanding of the clinical presentation, key investigations and time-sensitive management of this disease, as early initiation of treatment for TA can be vision- and life-saving.  相似文献   
13.
Implantation of the PRL, ACTH, beta-endorphin (beta-EP), and beta-lipotropin (beta-LPH)-secreting transplantable rat pituitary tumor 7315a resulted in a suppression of the PRL and the ACTH content of the anterior pituitary gland and also of the beta-EP/beta-LPH content of the neurointermediate (NI) lobe. Treatment with bromocriptine further diminished the anterior lobe PRL content, whereas haloperidol partially inhibited this tumor-mediated diminution. The administration of these drugs did not influence the suppressed ACTH content of the anterior pituitary lobe. The diminished beta-EP/beta-LPH content of the NI lobe of tumor-bearing rats became completely normal after treatment with haloperidol, whereas bromocriptine administration further diminished the NI lobe beta-EP/beta-LPH content. There was a close correlation between the anterior pituitary lobe PRL content and the beta-EP/beta-LPH content of the NI lobe in all four groups of rats taken together (including nontumor-bearing controls, control tumor rats, and tumor rats treated with bromocriptine or haloperidol; P less than 0.01). Implantation of the pure PRL-secreting pituitary tumor 7315b resulted in hyperprolactinemia and a suppression of the PRL content of the anterior lobe and the beta-EP/beta-LPH content of the NI lobe, without affecting the ACTH content of the anterior pituitary lobe. There was a negative correlation between the level of the circulating PRL concentration and the beta-EP/beta-LPH content of the NI lobe. These results suggest a possible relationship between the synthesis of PRL by the anterior pituitary lactotroph and of the hormones of the NI lobe. The level of the circulating PRL concentration may play, directly or indirectly, a role in the regulation of both systems.  相似文献   
14.

Background

Junctional adhesion molecule (JAM-) A is a transmembrane protein expressed in many cell types and maintains junctional integrity in endothelial cells. Upon inflammatory stimulation, JAM-A relocates to the apical surface and might thereby facilitate the recruitment of leukocytes.

Objective

Although inflammatory JAM-A redistribution is an established process, further effort is required to understand its exact role in the transmigration of mononuclear cells, particularly under atherogenic conditions.

Methods

By the use of RNA interference and genetic deletion, the role of JAM-A in the transmigration of T cells and monocytes through aortic endothelial cells was investigated. JAM-A–localization and subsequent mononuclear cell rolling, adhesion and transmigration were explored during endothelial inflammation, induced by oxidized LDL or cytokines.

Results

RNA interference or genetic deletion of JAM-A in aortic endothelial cells resulted in a decreased transmigration of mononuclear cells. Treatment of the endothelial cells with oxLDL resulted in an increase of both permeability and apical JAM-A presentation, as shown by bead adhesion and confocal microscopy experiments. Redistribution of JAM-A resulted in an increased leukocyte adhesion and transmigration, which could be inhibited with antibodies against JAM-A or by lovastatin-treatment, but not with the peroxisome proliferator activated receptor gamma-agonist pioglitazone.

Conclusions

This study demonstrates that redistribution of JAM-A in endothelial cells after stimulation with pro-atherogenic oxidized lipoproteins results in increased transmigration of mononuclear cells. This inflammatory dispersal of JAM-A could be counteracted with statins, revealing a novel aspect of their mechanism of action.  相似文献   
15.
Splenectomy in myeloid metaplasia   总被引:3,自引:0,他引:3  
Silverstein  MN; ReMine  WH 《Blood》1979,53(3):515-518
Between 1960 and 1977, 50 patients with agnogenic myeloid metaplasia were splenectomized. Twenty-five of 26 patients with painful splenomegaly, 4 of 9 patients with refractory hemolytic anemia, 4 of 10 patients with refractory thrombocytopenia, and 4 of 4 patients with portal hypertension showed significant benefit from the procedure. There were five immediate postoperative deaths. Four of these deaths occurred early in our series of splectomies for myeloid metaplasia before 1970. Only one death has occurred in the last 21 patients operated on. Survival following splenectomy averaged 25.5 mo.  相似文献   
16.
AIM: To evaluate existing evidence for the association between different type of brassiere exposures and the risk of breast cancer. METHODS: Ovid Medline, CINAHL, Cochrane Data Base of Systematic Reviews, Pubmed, Scopus, Proquest, Sciencedirect, Wiley Online Library, WanFang Data, Hong Kong Index to Chinese Periodicals, China Journal Net, Chinese Medical Current Contents, Chinese Biomedical Literature Database, China Academic Journals Full-Text database, Taiwan Electronic Periodical Services and HyRead; reference lists of published studies; original research studies published in English or Chinese examining the association between type and duration of brassiere-wearing and breast cancer risk. Data were abstracted by a first reviewer and verified by a second. Study quality was rated according to predefined criteria. “Fair” or “good” quality studies were included. Results were summarised by meta-analysis whenever adequate material was available. RESULTS: Twelve case-control studies were included in the review. Meta-analysis showed brassiere wearing during sleep was associated with a two times of increased odds. CONCLUSION: The present review demonstrates insufficient evidence to establish a positive association between the duration and type of brassiere wearing and breast cancer. Further research is essential; specifically, a large-scale epidemiological study of a better design is needed to examine the association between various forms of brassiere exposure in detail and breast cancer risk, with adequate control of confounding variables.  相似文献   
17.
Radiation-induced red cell damage: role of reactive oxygen species   总被引:1,自引:1,他引:1  
BACKGROUND: Cellular blood components are irradiated to prevent graft- versus-host disease in transfusion recipients at risk for this syndrome. Because gamma radiation can result in the production of reactive oxygen species, the role of reactive oxygen species was investigated in radiation-induced red cell damage. STUDY DESIGN AND METHODS: Whole blood from normal donors was exposed to various doses of t-butyl hydroperoxide (0-1 mM) and/or to gamma-radiation (0-50 Gy). Oxidative damage was assessed by the extent of lipid peroxidation (measured by thiobarbituric acid-reactive substances [TBARS]) and hemoglobin oxidation. Fresh blood was divided into three parts-one initially irradiated and stored, another stored with portions irradiated weekly, and a third stored without irradiation. TBARS and hemoglobin oxidation were measured weekly. RESULTS: As expected, t- butyl hydroperoxide induced TBARS formation and hemoglobin oxidation in a dose-dependent fashion. The gamma-radiation not only increased hemoglobin oxidation and TBARS formation, but also enhanced the t-butyl hydroperoxide effect on red cells. Red cell storage increased TBARS generation and hemoglobin oxidation in a time-dependent fashion. When radiation was administered either initially or after weekly storage, TBARS production and hemoglobin oxidation were increased over that measured in unirradiated paired controls. CONCLUSION: Gamma radiation at clinically used doses increases lipid peroxidation and hemoglobin oxidation in human red cells. The effect of gamma-radiation is accentuated by blood storage and induces damage independent of time of storage.  相似文献   
18.
WH Visser  MD  ; RHM de  Vriend  MSc ; NHWM Jaspers  MSc  ; MD Ferrari  MD  PhD 《Headache》1996,36(8):471-475
Sumatriptan, notably after subcutaneous administration, is highly effective in the acute treatment of migraine in the majority of patients. The response is consistent within patients and over time. To determine risk factors for nonresponse to sumatriptan, we compared clinical characteristics. In responders and nonresponders and, within patients, between attacks with and without response. We found no differences at the strict level of significance (P<0.001 because of multiple comparisons), but only tendencies for differences (0.001相似文献   
19.
Background Heart failure (HF) is a physically and socially debilitating disease that carries the burden of hospital re-admission and mortality. As an aging society, Hong Kong urgently needs to find ways to reduce the hospital readmission of HF patients. This study evaluates the effects of a nurse-led HF clinic on the hospital readmission and mortality rates among older HF patients in Hong Kong. Methods This study is a retrospective data analysis that compares HF patient in a nurse-led HF clinic in Hong Kong compared with HF patients who did not attend the clinic. The nurses of this clinic provide education on lifestyle modification and symptom monitoring, as well as titrate the medications and measure biochemical markers by following established protocols. This analysis used the socio-demographic and clinical data of HF patients who were aged ≥ 65 years old and stayed in the clinic over a six-month period. Results The data of a total of 78 HF patients were included in this data analysis. The mean age of the patients was 77.38 ± 6.80 years. Approximately half of the HF patients were male (51.3%), almost half were smokers (46.2%), and the majority received ≤ six years of formal education. Most of the HF patients (87.2%) belonged to classes II and III of the New York Heart Association Functional Classification, with a mean ejection fraction of 47.15 ± 20.31 mL. The HF patients who attended the clinic (n = 38, 75.13 ± 5.89 yrs) were significantly younger than those who did not attend the clinic (n = 40, 79.53 ± 6.96 yrs) (P = 0.04), and had lower recorded blood pressure. No other statistically significant difference existed between the socio-demographic and clinical characteristics of the two groups. The HF patients who did not attend the nurse-led HF clinic demonstrated a significantly higher risk of hospital readmission [odd ratio (OR): 7.40; P < 0.01] than those who attended after adjusting for the effect of age and blood pressure. In addition, HF patients who attended the clinic had lower mortality (n = 4) than those who did not attend (n = 14). However, such a difference did not reach statistical significance when the effects of age and blood pressure were adjusted. A significant reduction in systolic blood pressure [F (2, 94) = 3.39, P = 0.04] and diastolic blood pressure [F (2, 94) = 8.48, P < 0.01] was observed among the HF patients who attended the clinic during the six-month period. Conclusions The finding of this study suggests the important role of nurse-led HF clinics in reducing healthcare burden and improving patient outcomes among HF patients in Hong Kong.  相似文献   
20.
目的:蒿甲醚除了具有良好的临床治疗作用外,对正常组织有极大的副作用。实验拟观察蒿甲醚对大鼠肺泡Ⅱ型上皮细胞的影响。方法:实验于2005-09-20/2007-03-10在山东省泰山医学院生命科学研究所、中心实验室和机能实验室完成。①实验材料:蒿甲醚购自昆明制药厂,分析纯,使用前先进行预处理,处理方法:研磨后用溶液配成1g/L的母液,超声助溶解后供实验用。Wistar大鼠70只,体质量(70±15)g,雌雄不拘,由山东大学医学院实验动物中心提供。实验过程中对动物处置符合动物伦理学标准。②实验方法:将大鼠随机分为普通饲料对照组(n=10)和实验组(n=60),实验组分6个亚组,分别在饲料中加入0.1,0.2,0.4,0.8,1.6,3.2mg/kg的蒿甲醚。采用单细胞凝胶电泳技术观察大鼠肺泡Ⅱ型上皮细胞DNA的改变。结果:70只大鼠,饲养过程中实验组死亡6只,死亡原因为饲料添加蒿甲醚造成。当饲料中的蒿甲醚浓度为0.1mg/kg时,大鼠肺泡Ⅱ型上皮细胞DNA损伤率与对照组相比,差异无统计学意义;饲料中的蒿甲醚浓度超过0.2mg/kg时,大鼠肺泡Ⅱ型上皮细胞DNA损伤率明显增加,与对照组相比,差异有统计学意义。且损伤程度与饲料中蒿甲醚含量呈正相关。结论:当饲料中的蒿甲醚浓度超过0.2mg/kg时,蒿甲醚可在一定程度上改变肺泡Ⅱ型上皮细胞的DNA生物学特性。且随着蒿甲醚浓度的升高,这种损害更为明显。  相似文献   
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