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321.
Primitive neuroectodermal tumor (PNET) is usually aggressive and rapidlyprogressing and metastasizing tumor. Occurrence of the this type of tumorin the kidney is considered as unusual, and few cases have been reportedso far. We present a PNET arising from the kidney in a 23-year-old femalepatient.  相似文献   
322.
The cause of sleep is a complex question, which needs first, a clear distinction amongst the different meanings of a causal relationship in the study of a given behavior, second, the requisites to be met by a suggested cause, and third, a precise definition of sleep to distinguish behavioral from polygraphic sleep. This review aims at clarifying the meaning of the question and at showing the phylogenetic origin of the mammalian and avian sleep. The phylogenetic appearance of sleep can be approached through a study of the evolution of the vertebrate brain. This began as an undifferentiated dorsal nerve, which was followed by the development of an anterior simplified brain and ended with the formation of the multilayered mammalian neocortex or the avian neostriate. The successive stages in the differentiation of the vertebrate brain produced, at least, two different waking types. The oldest one is the diurnal activity, bound to the light phase of the circadian cycle. Poikilotherms control the waking from the whole brainstem, where their main sensorymotor areas lie. Mammals developed the thalamocortical lines, which displaced the waking up to the cortex after acquiring homeothermy and nocturnal lifestyle. In order to avoid competence between duplicate systems, the early waking type, controlled from the brainstem, was suppressed, and by necessity was turned into inactivity, probably slow wave sleep. On the other hand, the nocturnal rest of poikilotherms most probably resulted in rapid eye movement sleep. The complex structure of the mammalian sleep should thus be considered an evolutionary remnant; the true acquisition of mammals is the cortical waking and not the sleep.  相似文献   
323.
Familial hyperinsulinism (HI) is a disorder of pancreatic beta-cell function characterized by persistent hyperinsulinism despite severe hypoglycemia. To define the molecular genetic basis of HI in Ashkenazi Jews, 25 probands were screened for mutations in the sulfonylurea receptor (SUR1) gene by single-strand conformation polymorphism (SSCP) analysis of genomic DNA and subsequent nucleotide sequence analyses. Two common mutations were identified: (I) a novel in-frame deletion of three nucleotides (nt) in exon 34, resulting in deletion of the codon for F1388 (delta F1388) and (II) a previously described g-->a transition at position-9 of the 3' splice site of intron 32 (designated 3992-9g-->a). Together, these mutations are associated with 88% of the HI chromosomes of the patients studied. 86Rb+ efflux measurements of COSm6 cells co-expressing Kir6.2 and either wild-type or delta F1388 SUR1 revealed that the F1388 mutation abolished ATP-sensitive potassium channel (KATP) activity in intact cells. Extended haplotype analyses indicated that the delta F1388 mutation was associated with a single specific haplotype whereas the 3992-9g-->a mutation was primarily associated with a single haplotype but also occurred in the context of several other different haplotypes. These data suggest that HI in Ashkenazi Jews is predominantly associated with mutations in the SUR1 gene and provide evidence for the existence of at least two founder HI chromosomes in this population.   相似文献   
324.
The ability of an infusion of ex vivo expanded hematopoietic cells to ameliorate cytopenia following transplantation of hematopoietic stem cells (HSCs) is controversial. To address this issue, we measured the recovery of circulating leukocytes, erythrocytes, and platelets in lethally irradiated mice transplanted with 10(3) enriched HSCs, with or without their expanded equivalent (EE) generated after 7 days of culture in interleukin-3 (IL-3), IL-6, granulocyte colony-stimulating factor and Steel Factor. Two HSC populations differing in their content of short-term repopulating progenitors were evaluated. Thy-1loLIN-Sca- 1+ (TLS) bone marrow (BM) is enriched in colony-forming cells (CFCs), day 8 and day 12 spleen colony-forming units (CFU-S) (435 +/- 19, 170 +/- 30, and 740 +/- 70 per 10(3) cells, respectively), and stem cells with competitive long-term repopulating potential (> or = 1 per 43 cells). Thy-1loSca-1+H-2Khl cells (TSHFU) isolated from BM 1 day after treatment of donor mice with 5-fluorouracil (5-FU) are also highly enriched in competitive repopulating units (CRU, > or = 1 per 55 cells), but are depleted of CFCs, day 8 and day 12 CFU-S (171 +/- 8, 0 and 15 +/- 4 per 10(3) cells, respectively). Recipients of 10(3) TLS cells transiently recovered leukocytes to > or = 2,000/microL in 12 days, but sustained engraftment required 25 days. Platelets recovered to > or = 200,000/microL in 15 days, and erythrocytes never decreased below 50% of normal. Mice transplanted with 10(3) TSHFU cells recovered leukocytes in 15 days, and platelets and erythrocytes in 18 days. Recipients of unseparated normal or 5-FU-treated BM cells (containing 10(3) TLS or TSHFU cells) recovered safe levels of blood cells in 9 to 12 days, suggesting that unseparated marrow contains early engrafting cells that were depleted by sorting. Upon ex vivo expansion, total cells, CFCs and day 12 CFU-S were amplified 2,062-,83- and 13-fold, respectively, from TLS cells; and 1,279-, 259- and 708-fold, respectively, from TSHFU cells. Expanded cells could regenerate the majority of lymphocytes and granulocytes in primary (17 weeks) and secondary (26 weeks) hosts and were only moderately impaired compared to fresh HSCs. The EE of TSHFU cells was more potent than that of TLS cells, suggesting that more highly enriched HSCs are more desirable starting populations for this application. When mice were transplanted with 10(3) TSHFU cells and their EE, the duration of thrombocytopenia was shortened from 18 to 12 days, and anemia was abolished. Leukocytes were also elevated on days 9 to 12, although sustained recovery was not accelerated. Anemia was also abrogated in recipients of 10(3) TLS cells and their EE. Early platelet counts were slightly higher than with TLS cells alone, but leukocyte recovery was not improved. These data confirm that TLS cells contribute to early and sustained hematopoiesis, and demonstrate a benefit of ex vivo expanded cells in accelerating engraftment of more primitive TSHFU stem cells depleted of progenitors.  相似文献   
325.

Objective

To evaluate the results of multiple closed intramedullary Kirschner wiring via a supracondylar entry point for humeral shaft fractures.

Patients and methods

The charts of 37 patients with humeral shaft fractures treated with the Hackethal''s technique between January 2007 and December 2011 were reviewed retrospectively. The operation was performed with the patient lying in supine (n = 22) or lateral (n = 15) position. The elbow was flexed over an articulated support with the arm kept in a vertical position. Thirty-three patients were available for final evaluation with a mean follow-up delay of 14 (range, 6–24) months. We were concerned about fracture union, range of motion of the shoulder and the elbow, and complications. Final evaluation used the criteria by Qidwai.

Results

Bone union rate was 94%. Restriction of ranges of motion of the shoulder more than 20° was noticed in two patients due to protruding wires. Three patients developed limitation of elbow extension owing to backing out of the wires. The overall results were excellent (n = 26; 79%), good (n = 4; 12%), and poor (n = 3; 9%).

Conclusion

Closed Hackethal''s technique using K-wires gives satisfactory results in terms of bone union and elbow and shoulder function in selected humeral shaft fractures. The articulated support precludes the transolecranon traction.  相似文献   
326.
Giant omphaloceles present a reconstructive challenge in planning, management, and eventual closure of the abdominal wall defect. The goal of reconstruction is to recreate a functional abdominal wall domain and return the extra-anatomically placed viscera into the peritoneal cavity in a safe manner. Traditionally, placement of tissue expanders has been in the subcutaneous and intramuscular planes. Recently, however, there have been reports of intra-abdominal placement of expanders. We present a detailed review of the literature regarding the use of tissue expanders in the management of giant omphaloceles with specific emphasis on the intra-abdominal technique of placement. We also present a case report with the longest follow-up till date in which the patient underwent staged reduction using the intra-abdominal approach. Initial reports of this modality are promising both as a primary strategy and in patients in whom conventional techniques have failed. Results from our review of literature and case report suggest that this technique appears to be durable and effective with successful functional and cosmetic outcomes.  相似文献   
327.
Kurc E  Sanioglu S  Ozgen A  Aka SA  Yekeler I 《Vascular》2012,20(3):150-155
The aim of this study is to evaluate the validity of the Glasgow aneurysm score (GAS) and Hardman index in patients operated on because of ruptured abdominal aortic aneurysm (rAAA), and determining preoperative risk factors that affect in-hospital mortality. One hundred one patients operated on to repair a rAAA within the last 10 years were included. The GAS and Hardman index were calculated for each patient separately. The relation between in-hospital mortality and the Hardman index and GAS was analyzed by means of the receiver-operator characteristic (ROC) curve. Univariate and multivariate methods of analyses were used to determine preoperative risk factors. Average age was 69 ± 8, and in-hospital mortality rate was 51.5%. Analysis of the ROC curve showed that the Hardman index had an area under the curve (AUC) = 0.71 (95% confidence interval [CI], 0.593-0.800, P = 0.0002) for predicting in-hospital mortality. The GAS had an AUC = 0.77 (95% CI, 0.680-0.851, P < 0.0001). The results of multivariate analysis revealed the presence of the following preoperative risk factors: age more than 63 years (odds ratio [OR], 4.4; 95% CI, 1.17-16.49, P = 0.028); loss of consciousness (OR, 9.33; 95% CI, 1.94-44.86, P = 0.005); creatinine higher than 1.7 mg/dL (OR, 5.52; 95% CI, 1.92-15.85, P = 0.001); and pH lower than 7.31 (OR, 3.77; 95% CI, 1.18-11.99, P = 0.024). In conclusion, the Hardman index and GAS have a significant correlation with in-hospital mortality rates. Nevertheless, a high score does not necessarily correspond with a definite mortality. This is why scoring systems could not be considered as the sole criterion for choosing patients for this study. Clinical experience was still the leading factor in deciding against or in favor of surgery.  相似文献   
328.
The benefits of angiotensin-converting enzyme (ACE) inhibition in the management of cardiac failure have been extensively documented. However, little is known about its impact upon the investigation and management of this condition. We assessed how patients diagnosed as having cardiac failure were investigated, which patients were treated with ACE inhibitors and with what dosages. We reviewed the case notes of all 343 patients discharged from Aberdeen Royal Infirmary 1 July-31 December 1992 with a diagnosis of cardiac failure. In addition, a questionnaire was sent to the general practitioners of the 166 patients still alive in October 1994. Only 40% of patients were discharged from hospital on ACE inhibitors. In 58.8%, the diagnosis of cardiac failure was based purely on clinical or radiological grounds. At discharge, 76.1% of patients were on lower doses of ACE inhibitors than those used in the major survival studies; with 68.9% receiving similar doses two years later. The majority of patients with heart failure are under- investigated and under-treated.   相似文献   
329.
Abstract Ethnic differences in lung function are well recognized, hence the use of normative data should therefore be based on reference equations that are derived specifically for different ethnic groups. We have collected data ( n =406) for population-based reference values of lung function from randomly selected samples of healthy non-smoking adults of both gender (aged 20–79 years) for each of the three major ethnic groups (Chinese, Malay and Indians) in Singapore. Lung function forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1/FVC, diffusion capacity (transfer factor) for carbon monoxide (DLCO), total lung capacity (TLC), residual volume (RV), RV/TLC and functional residual capacity (FRC) was measured using standardization procedures and acceptability criteria recommended by the American Thoracic Society. Lung function values were predicted from age, height, weight, body mass index (BMI) and transformed variables of these anthropometric measures, using multiple regression techniques. Ethnic differences were demonstrated, with Chinese having the largest lung volumes and flow rates, and Indians the smallest. These prediction equations provide improved and additional (TLC, RV, RV/TLC, FRC) population-based reference values for assessment of pulmonary health and disease in Singapore  相似文献   
330.
呼吸中枢低氧反应性的高低受遗传的调控,尽管动物实验发现了多个候选基因,但目前尚未见人体相关基因的报告.发作性睡病(narcolepsy)是一种少见睡眠疾病,以难以控制的嗜睡、发作性猝倒、睡瘫、入睡幻觉及夜间睡眠紊乱为主要临床特点,超过95%的典型患者存在人类白细胞抗原(HLA)DQB1*0602基因阳性、脑脊液下丘脑分泌素降低或消失等表现.患者常合并睡眠呼吸暂停,动物实验结果显示下丘脑分泌素缺乏可导致清醒状态下的呼吸中枢高CO2反应性降低,提示发作性睡病患者存在呼吸调节功能缺陷.  相似文献   
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