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51.
Serum lipoprotein profiles in 3182 children, ages 5-14 years, were studied in a biracial community as part of the Bogalusa Heart Study to describe the early natural history of atherosclerosis. White and black children showed similar mean levels of beta-lipoproteins. Pre-beta-lipoprotein levels, however, were significantly higher in white shildren, while significantly higher levels of alpha-lipoprotein were found in black children. Girls had generally higher levels of beta- and pre-beta-lipoprotein and lower levels of alpha-lipoprotein than boys, although the differences were not significant at each age group. With age there was little change in alpha-lipoprotein levels, a significant increase in pre-beta-lipoprotein levels and a slight but significant decrease between 11 and 14 years in beta-lipoprotein levels. The correlation of alpha-lipoprotein was negative with beta-lipoprotein and, to a greater extent, with pre-beta-lipoprotein. The above inverse relationships were significantly greater in white children than in black children, suggesting differences in lipoprotein profiles in the two groups. Lipoprotein values from a total community study are now available for comparison with the currently recommended upper normal limits for lipoproteins. Since only a very small percentage of children could be considered as hyperlipoproteinemic by those specific levels in this community, we suggest that distributions and percentiles be used to evaluate children for hyperlipoproteinemia.  相似文献   
52.
We present a case of a 71-year-old woman who was incidentally found to have aberrant retropharyngeal internal carotid artery, lying very close to the pharyngeal mucosa, on imaging. Radiologists, otolaryngologists and anaesthetists should be aware of this clinically significant variant which can result in life-threatening bleeding during procedures in the oral cavity or oropharynx.  相似文献   
53.
Schwannomas are benign soft tissue tumours that arise from nerve sheath cells. They are rare in the salivary glands and are thought to arise from the parasympathetic nerves. We report the case of a 69-year-old man who presented with a painless right submandibular mass that appeared to resemble a pleomorphic adenoma on ultrasonography and, on this basis, proceeded to surgical excision of the gland. We review the relevant literature and highlight the diagnostic pitfalls.  相似文献   
54.
A physical theory of protein secondary structure is proposed and tested by performing exceedingly simple Monte Carlo simulations. In essence, secondary structure propensities are predominantly a consequence of two competing local effects, one favoring hydrogen bond formation in helices and turns, the other opposing the attendant reduction in sidechain conformational entropy on helix and turn formation. These sequence specific biases are densely dispersed throughout the unfolded polypeptide chain, where they serve to preorganize the folding process and largely, but imperfectly, anticipate the native secondary structure.  相似文献   
55.
Calibration of a three-dimensional multimodal digital breast tomosynthesis (DBT) x-ray and non-fiber based near infrared spectral tomography (NIRST) system is challenging but essential for clinical studies. Phantom imaging results yielded linear contrast recovery of total hemoglobin (HbT) concentration for cylindrical inclusions of 15 mm, 10 mm and 7 mm with a 3.5% decrease in the HbT estimate for each 1 cm increase in inclusion depth. A clinical exam of a patient’s breast containing both benign and malignant lesions was successfully imaged, with greater HbT was found in the malignancy relative to the benign abnormality and fibroglandular regions (11 μM vs. 9.5 μM). Tools developed improved imaging system characterization and optimization of signal quality, which will ultimately improve patient selection and subsequent clinical trial results.OCIS codes: (120.3890) Medical optics instrumentation, (170.0110) Imaging systems, (170.3830) Mammography  相似文献   
56.

Purpose

Bone graft is often recommended as an adjuvant for treatment of scaphoid nonunions. However, recent literature has suggested that fibrous nonunion may be suited to treatment with rigid fixation without bone grafting. This work reported on outcomes of compression screw fixation for established scaphoid fibrous nonunions without bone graft.

Methods

Fourteen patients underwent surgical compression screw fixation without bone grafting of scaphoid fibrous nonunion between January 1, 2000, and December 31, 2012, with minimum follow-up until the time of clinical and radiographic healing. Fibrous nonunion of the scaphoid was defined as a scaphoid fracture with all of the following features: (1) persistent tenderness, (2) incomplete trabecular bridging on three X-ray views, (3) injury that had occurred at a minimum of 6 months prior to surgery, and (4) identification of fibrous union at the time of surgery. Outcomes were assessed with range of motion assessment, Disability of the Arm, Shoulder and Hand (DASH) scores, and plain radiographs.

Results

Twelve of the 14 patients healed successfully, while two patients required secondary vascularized bone grafting. Both unhealed patients sustained proximal pole fractures and had a duration of ≥1 year from injury to surgery. Average time to healing was 4.4 ± 2.0 months. Average flexion was 73 ± 22° and average extension was 66 ± 22° postoperatively. Average grip strength was 90 ± 25 lbs on the operative side. Mean postoperative pain score was 1.4 (range, 0 to 7). Mean postoperative DASH score was 10.2 (range, 0 to 52). Increasing age and an interval from injury to surgery of >1 year correlated with worse DASH and pain scores.

Conclusions

Patients with fibrous scaphoid nonunion demonstrated good results with rigid fixation without bone grafting. Increasing age and >1-year interval between injury and surgery resulted in lower self-assessed outcomes.

Level of Evidence

Therapeutic Level IV, retrospective case series  相似文献   
57.
The adult heart diseases, coronary artery disease and essential hypertension, are now clearly recognized to begin in childhood. The evidence comes from autopsy studies of cardiovascular-renal changes in the first two decades of life. Cardiovascular risk factors can be identified in children just as in adults and these have a high correlation with the anatomic disease. This relationship underscores the importance of risk factor screening of children. Of interest is that clinical risk factors tend to persist within a rank (track) so that studies in childhood can be predictive of future levels. Behavior and lifestyle of eating, cigarette smoking, alcohol intake, and use of oral contraceptive pills influence risk factors in children. Familial aggregation of risk factors are also noted. Studies of apolipoproteins, B and A-I, have identified subsets of children that have a greater frequency of paternal myocardial infarction. The findings from the Bogalusa Heart Study and other epidemiological studies of children show the need to begin prevention of adult heart disease in early life. Approaches to prevention should include high risk families and children and a public health or population approach. Cardiovascular health education for elementary school children should be directed to children in the general population in an effort to encourage them to adopt healthy life styles.  相似文献   
58.
Multinucleated giant cells of osteoclastic type are known to occur in nodal and extranodal lesions of Langerhans cell histiocytosis (LCH). These giant cells are thought to be derived from phagocytic histiocytes, which correlate with the degree of necrosis in LCH lesions. Emperipolesis commonly seen in Rosai–Dorfman disease is a distinct phenomenon characterized by intact phagocytosed cells in an intracytoplasmic vacuole protected from proteolytic digestion. We present a case of emperipolesis of inflammatory cells especially of eosinophils by multinucleated giant cells of Langhans type in a lymph node involved by LCH—a finding that has not been described previously in the literature. Diagn. Cytopathol. 2015;43:1000–1002. © 2015 Wiley Periodicals, Inc.  相似文献   
59.
60.
This phase IIa study evaluated the safety and tolerability of sotatercept, and its effects on bone metabolism and haematopoiesis in newly diagnosed and relapsed multiple myeloma (MM) patients. Patients were randomized (4:1) to receive four 28‐d cycles of sotatercept (0·1, 0·3, or 0·5 mg/kg) or placebo. Patients also received six cycles of combination oral melphalan, prednisolone, and thalidomide (MPT). Thirty patients were enrolled; six received placebo and 24 received sotatercept. Overall, 25% of patients received all four sotatercept doses; 71% of sotatercept‐treated patients had ≥1 dose interruption mainly due to increases in haemoglobin levels. Grade ≥3 adverse events (AEs) were reported in 17% of patients receiving placebo and 58% receiving sotatercept. Grade 4 AEs in sotatercept‐treated patients were neutropenia, granulocytopenia, and atrial fibrillation (one patient each). In patients without bisphosphonate use, anabolic improvements in bone mineral density and in bone formation relative to placebo occurred, whereas bone resorption was minimally affected. Increases in haemoglobin levels, versus baseline, and the duration of the increases, were higher in the sotatercept‐treated patients, with a trend suggesting a dose‐related effect. Multiple doses of sotatercept plus MPT appear to be safe and generally well‐tolerated in MM patients.  相似文献   
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