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2.
Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献
3.
Shared care: a review of the literature 总被引:7,自引:1,他引:6
This review examines broad issues of concern regarding the primary/secondarycare interface. The main purpose was to identify areas of goodpractice which could be adapted for more general use. One ofthe most fundamental aspects identified was communication, whichis discussed in some detail. Also covered are shared prescribingand disease management. The data suggest that the most effectivesystem(s) of shared care has yet to be established. Furtherqualitative and economic evaluations are required, taking intoaccount patient preferences. Although the literature does describecertain practice exemplars, it is clear that inter- and intra-professionalcommunication continues to be a problem. Whilst informationtechnology may provide some of the solutions, it is concludedthat a culture change, which compels health professionals tomake sharing of patient information a much higher priority,is reauired. Keywords. Shared care, seamless care, hospital, general practice, family practice. 相似文献
4.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
5.
6.
A 15-year-old boy presented with hydrocephalus due to a pineal tumor presumed to be a germinoma. After a shunting procedure, gross total tumor resection was carried out via an occipital transtentorial approach. Histopathological examination of the tissue demonstrated that, in addition to the expected germinoma, the tumor also contained areas of astrocytoma and areas that, taken in isolation as in a needle biopsy, could have been diagnosed as pineocytoma. The diagnosis and therapy of a pineal tumor of mixed histological types such as this lesion would be seriously compromised by "conventional" empiric radiation and even a stereotactic needle biopsy may not have provided an adequate tissue sample. 相似文献
7.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
8.
K Danadian V Lewy J J Janosky S Arslanian 《The Journal of clinical endocrinology and metabolism》2001,86(7):3022-3026
Rates of obesity and type 2 diabetes are higher in African-American (AA), compared with American white (AW), adults and children. It is not known whether biologic and/or environmental differences are responsible for this racial disparity. We and others have demonstrated that AA children are hyperinsulinemic, compared with their AW peers. This investigation tested the hypothesis that hyperinsulinemia in AA children is associated with lower rates of lipolysis, which could be a risk factor for future obesity. Forty prepubertal children (20 AA and 20 AW) with comparable body composition (assessed by dual-energy x-ray absorptiometry) and visceral adiposity (evaluated with computed tomography scan) were studied. Total body lipolysis was measured with [(2)H(5)]glycerol after overnight fasting. Basal lipolysis was approximately 40% lower in AA vs. AW children, whether the data were expressed for total body (85.7 +/- 8.9 vs. 130.3 +/- 14.1 micromol/min, P = 0.011) or per-kilogram BW (2.4 +/- 0.2 vs. 3.8 +/- 0.4 micromol/min.kg, P = 0.002) or per kilogram fat free mass (FFM) (3.3 +/- 0.3 vs. 5.2 +/- 0.5 micromol/min.kg FFM, P = 0.004), or per kg fat mass (FM) (13.7 +/- 1.6 vs. 21.3 +/- 3.3 micromol/min.kg FM, P = 0.046). Fasting insulin levels were higher in AA children (99.6 +/- 7.8 vs. 77.4 +/- 5.9 pmol/L, P = 0.032). Lipolysis correlated positively with fat mass, percent body fat, and abdominal fat mass. However, in multiple-regression analysis models after controlling for insulin and body composition, race remained a significant contributor to the variance in lipolysis. In summary, the present study demonstrates that rates of lipolysis are significantly lower in AA children, compared with their white peers. This may constitute an early metabolic phenotype that may mediate fat trapping and susceptibility to obesity in a specific environmental context of energy excess conducive to fat accretion. 相似文献
9.
R J Strassman O Appenzeller A J Lewy C R Qualls G T Peake 《The Journal of clinical endocrinology and metabolism》1989,69(3):540-545
Strenuous exercise increases plasma melatonin, cortisol, and beta-endorphin concentrations. Furthermore, a relationship between endogenous opioids and melatonin has been proposed. We measured plasma melatonin, cortisol, and beta-endorphin in 46 subjects before and after a 28.5-mile high altitude race. Thirteen of the subjects received the orally active opioid antagonist naltrexone immediately before the race. The mean plasma melatonin, cortisol, and beta-endorphin levels were higher after the race than before it; the melatonin results were confirmed by gas chromatography-mass spectrometry assay of 12 subjects. Naltrexone had no effect on the increase in any of the three hormones. The run-induced increases in plasma melatonin, beta-endorphin, and cortisol were negatively correlated with finishing time, but only the plasma beta-endorphin and cortisol rises correlated with each other. We conclude that prolonged exercise in trained athletes can increase plasma melatonin and that this rise is not due to the concomitant opioid release. 相似文献
10.
Acanthosis Nigricans, insulin action, and hyperandrogenism: clinical, histological, and biochemical findings 总被引:7,自引:0,他引:7
A Dunaif G Green R G Phelps M Lebwohl W Futterweit L Lewy 《The Journal of clinical endocrinology and metabolism》1991,73(3):590-595
Acanthosis nigricans (AN) is a frequent clinical finding in hyperandrogenic women. Its presence has been used to subgroup such women. We performed this study in order to determine the actual histological prevalence of AN and its relationship to sex hormone levels and insulin action. Insulin-mediated glucose disposal was determined by the euglycemic clamp technique, and neck or axillary skin biopsies were graded blind for the presence and severity of AN in lean and obese women with the polycystic ovary syndrome (PCO) and in age- and weight-matched normal ovulatory controls. AN was present on clinical examination in 11 of 13 obese PCO, 3 of 6 lean PCO, 4 of 14 obese normal, and 0 of 4 lean normal women. AN was present on histological examination in 13 of 13 obese PCO, 5 of 6 lean PCO, 13 of 14 obese normal, and 1 of 4 lean normal women. The severity of histological AN was most highly correlated with insulin-mediated glucose disposal (r = -0.61; P less than 0.001) rather than fasting (r = 0.46; P less than 0.05) or glucose-stimulated insulin levels (r = 0.48; P less than 0.01). The only sex steroid correlated with histological AN was dehydroepiandrosterone sulfate (r = 0.46; P less than 0.01). We conclude that 1) clinical skin examination was very insensitive for detecting AN; 2) the best biochemical correlate of histological AN was decreased insulin action, rather than insulin or androgen levels per se; and 3) AN is a very common epiphenomenon of insulin resistance, and its clinical presence should not be used as a criterion for stratifying hyperandrogenic women. 相似文献