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1.
Homozygous familial hypercholesterolemia (HFH) is a very rare autosomal dominant disease characterized by accelerated severe atherosclerosis. We examined 18 patients from 9 families with HFH. The age range was 6-30 years (mean = 16 years). Male to female ratio was equal. All patients had huge, multiple tuberous xanthomas on the skin and tendons. Mean +/- standard deviation of plasma cholesterol, triglycerides, low-density lipoproteins (LDL), and high-density lipoproteins (HDL) cholesterol levels were 608 +/- 89, 122 +/- 39, 550 +/- 88, and 26 +/- 8 mg/dl, respectively. Five patients (28%) had angina pectoris, two sustained a myocardial infarction, and one died at the age of 15 years. Two-dimensional echocardiography demonstrated supravalvular aortic stenosis in 3 of the 13 patients (23%). Coronary arteriography performed in 11 patients demonstrated significant obstruction in 6 patients, 2 each with single-, double-, and triple-vessel disease. Left main stenosis was present in 3 patients (27%). Supravalvular aortic narrowing was demonstrated in 6 patients (54%) and was associated with a gradient in 2 (25 and 35 mmHg, respectively). Segmental contraction abnormalities were detected in 2 of the 11 patients (18%). It is concluded that coronary artery disease is prevalent in patients with HFH and, based on the data presented, we recommend the performance of noninvasive technique, coronary arteriography and supravalvular aortography at an early age to detect and to follow the progression of the disease.  相似文献   
2.
We assessed the effect of long-term therapy with inhaled beclomethasone dipropionate (BDP) on the pituitary-adrenal axis, by measuring the integrated concentration (IC) of plasma cortisol in eight children with asthma (age, 6-16 years) who regularly used inhaled BDP in doses ranging from 8 to 26.5 micrograms/kg (200-450 micrograms/day) for 6 months to 4 years. The control group included six children (age, 6-16 years) who had the IC of plasma cortisol measured as part of an endocrinological evaluation and were found to be healthy. Cortisol concentration was measured in blood samples collected continuously over a 24-hr period. Mean IC of plasma cortisol in the study group was significantly lower than in the healthy controls (mean +/- SD, 4.9 +/- 3.3 vs 9.1 +/- 1.9 micrograms/mL; P less than 0.02). Cortisol response to 0.25 mg ACTH (iv) was abnormal in one of the eight BDP-treated patients. No correlation was found between IC of plasma cortisol and the BDP dose, severity of asthma, height percentile, or the Tanner stage. We conclude that long-term therapy, even with relatively conventional doses of inhaled BDP may cause reduction in the normal physiological secretion of cortisol. The clinical relevance of low IC of plasma cortisol is not clear, but it may reflect partial suppression of the pituitary-adrenal axis.  相似文献   
3.
Oxidation of low-density lipoprotein (LDL) was shown to occur in vivo and involved lipid peroxidation and apolipoprotein modification. We studied the effect of oxidized-LDL (Ox-LDL) on plasma coagulation by measuring prothrombin time (PT) and partial thromboplastin time (PTT) following the addition of Ox-LDL to normal plasma. Ox-LDL, but not native LDL, caused prolongation of PT and PTT by 30% in a dose- and time-dependent pattern. This effect was also shown to be present following lipoprotein delipidation, suggesting that it was the apolipoprotein fraction of Ox-LDL, but not its lipid fraction, that was responsible for the prolongation of PT and PTT. This was further substantiated since similar effect could be obtained by adding LDL treated with trinitrobenzenesulphonic acid to block the lysine groups, as occurs in oxidized LDL. Ox-LDL, unlike LDL, was found to reduce plasma ionized calcium by 33%. Moreover, adding calcium ions to Ox-LDL negated its effect on PT and PTT, suggesting that Ox-LDL apolipoprotein may influence coagulation by binding calcium ions.  相似文献   
4.
5.
Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.  相似文献   
6.
Primitive Neuroectodermal Tumors of the Central Nervous System   总被引:2,自引:0,他引:2  
Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers.  相似文献   
7.
Cortical auditory evoked potentials (N1 wave) were studied in 24 adults (12 men, 12 women) and 20 children (12 boys, 8 girls; age: 4-8 years). In adults, this wave was recorded with maximal amplitude at frontocentral sites, peaking at about 100 ms poststimulation, whereas in children the auditory response displayed maximal amplitude at the midtemporal sites, with a positive wave at about 100 ms and a large negative wave at approximately 170 ms. Moreover, the modulatory effects of intensity on N1 amplitude were prominent at frontocentral sites in adults and at temporal sites in children. Frontocentral negative response was also recorded in children but was smaller in amplitude and longer in peak latency (around 140 ms) than in adults; responses were of greater amplitude at the frontal site than at the vertex before 6 years of age, whereas the reverse was more often found after this age. These data suggest great differences with age in the neural generators contributing to auditory evoked potentials recorded in the N1 latency range.  相似文献   
8.
We compared histomorphological features and molecular expression profiles of adrenocortical adenomas (ACAd) and carcinomas (ACCa). A critical histopathological review (mean, 11 slides per patient) was conducted of 37 ACAd and 67 ACCa. Paraffin-embedded tissue cores of ACAd (n = 33) and ACCa (n = 38) were arrayed in triplicate on tissue microarrays. Expression profiles of p53, mdm-2, p21, Bcl-2, cyclin D1, p27, and Ki-67 were investigated by immunohistochemistry and correlated with histopathology and patient outcome using standard statistical methodology. Median follow-up period was 5 years. Tumor necrosis, atypical mitoses, and >1 mitosis per 50 high-power fields were factors that were highly specific for ACCa (P <.001). Number (0 to 4) of unfavorable markers [Ki-67 (+), p21 (+), p27 (+), mdm-2(-)] expressed was significantly associated with mitotic activity and morphologic index (i.e., number of adverse morphologic features) and highly predictive of malignancy (P <.001). Ki-67 overexpression occurred in 0 ACAd and 36% ACCa (P <.001) and was significantly associated with mitotic rate and unfavorable morphologic index (P <.001). Tumor necrosis, atypical mitoses, >5 mitoses per 50 high-power fields, sinusoidal invasion, histologic index of >5, and presence of more than two unfavorable molecular markers were associated significantly with metastasis in ACCa. Well-established histopathologic criteria and Ki-67 can specifically distinguish ACCAd from ACCa. Tumor cell proliferation (Ki-67) correlates with mitotic activity and morphologic index. Tumor morphology is a better predictor of metastatic risk in ACCa than current immunohistochemistry-detected cell cycle regulatory and proliferation-associated proteins.  相似文献   
9.
Abstract. Morbidity and mortality in cystic fibrosis patients is mainly attributed to pulmonary infection and inflammation. Chemokines play a pivotal role in the inflammatory process. Although genotype-phenotype correlation in cystic fibrosis patients has been defined, a clear relationship between the defect in the cystic fibrosis transmembrane regulator (CFTR) gene and pulmonary inflammation has not been established. The aim of this study was to assess whether serum chemokines levels in cystic fibrosis patients correlate with genotype and pulmonary function tests, as well as with other clinical characteristics. Serum levels of interleukin-8, RANTES, and monocyte chemoattractant protein-1 were measured in 36 cystic fibrosis patients grouped according to their genotype. Group A included 25 patients who carried two mutations associated with a pathological sweat test and pancreatic insufficiency (F508, W1282X, G542X, N1303K, S549R). Group B included 11 compound heterozygote patients who carried one mutation known to cause mild disease with borderline or normal sweat test and pancreatic sufficiency (3849+10kb C to T, 5T). Associations between chemokine levels, genotype, pulmonary function, Pseudomonas aeruginosa colonization, age, sweat chloride level, and pancreatic and nutritional status were examined. Mean interleukin-8 and monocyte chemoattractant protein-1 levels were significantly higher in group A than group B (11.4±2.1 pg/ml vs. 5±0.9 pg/ml and 157±16 pg/ml vs. 88.8±16.4 pg/ml, respectively) (P<0.01). No difference in RANTES levels were found between groups. interleukin-8 levels were inversely related to forced expiratory volume in 1 s (r=-0.37, P<0.02), while there was no association between the latter and RANTES and monocyte chemoattractant protein-1 levels. The Pseudomonas colonization rate was higher among group A patients than group B (88% vs. 40%, P<0.01). No relationship was found between measured chemokines and age, sweat chloride levels, and pancreatic and nutritional status. Our study demonstrates an association between interleukin- 8, forced expiratory volume, and cystic fibrosis genotype. Hence, elevated interleukin-8 serum levels could serve as an indicator of an early inflammatory process and encourage the initiation of anti-inflammatory treatment.  相似文献   
10.
Hananyah  Glaubman  Israel  Orbach  Ygal  Gross  Orit  Aviram  Irene  Frieder  Meira  Frieman  Odeda  Pelled 《Psychophysiology》1979,16(5):467-470
The hypothesis that a load on focal attention prior to sleep results in subsequent changes in sleep patterns was investigated. Eight females and 2 males slept in the laboratory for 4 nights: 2 adaptation nights, 1 experimental night preceded by a focal attention load, and 1 control night preceded by relaxed activity. On the experimental night, time in bed, total sleep time, and stage REM sleep were significantly longer than on the control night. The results support the hypothesis and suggest that attention during REM sleep has a unique character.  相似文献   
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