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41.
This study attempts to document the occurrence of tumors with respect to clock hour location and distance from the macula and to evaluate tumor location in relation to retinal topography and light dose distribution on the retinal sphere. Analysis of patterns of tumor initiation may provide new evidence to clarify the controversy regarding the possible light-related etiology of choroidal melanoma. Incident cases of choroidal and ciliary body melanoma in Massachusetts residents diagnosed between 1984 and 1993 were the basis for analysis. Conventional fundus drawings and photos were used to assess the initiation site of each tumor. The initiation site was defined as the intersect between the largest tumor diameter and the largest perpendicular diameter of the tumor. Initiation sites were recorded using spherical coordinates. The retinal sphere was divided into 61 mutually exclusive sectors defined according to clock hour and anteroposterior distance from the macula. Rates of initiation were computed for each sector, overall, and according to gender and other clinical factors. Results were similar in left and right eyes; therefore, these were combined in analysis. Tumor initiation had a predilection for the macula (P < 0.0001). Overall, no significant clock hour preference was observed (P = 0.63). However, the parafoveal zone showed a strong circular trend (P < 0.01), with highest rates occurring in the temporal region, and the lowest rates occurring in the nasal region. Rates of occurrence in six progressively more anterior concentric zones (designated as the foveal, parafoveal, posterior, peripheral, anterior, and ciliary body zones) were 21.4, 14.2, 12.1, 8.9, 4.5, and 4.3 counts per spherical unit per 1000 eyes, respectively. Concentric zone location did not vary by gender (P = 0.93) or laterality (P = 0.78). However, posterior location was associated with light iris color (P = 0.01). Tumor diameters were largest in the peripheral region of the fundus and smallest in the macular and ciliary body zone (P < 0.001). Clock hour location was not influenced by gender (P = 0.74), laterality (P = 0.53), iris color (P = 0.84), or tumor diameter (P = 0.73). Results suggest that tumor initiation is not uniformly distributed, with rates of occurrence concentrated in the macular area and decreasing monotonically with distance from the macula to the ciliary body. This pattern is consistent with the retinal topography and correlates positively with the dose distribution of solar light on the retinal sphere. 相似文献
42.
43.
The relationship between serum thyroxine (T4) and thyroxine-binding globulin (TBG) has been studied in "euthyroid" subjects. The T4/TBG ratios in these subjects has been calculated and compared with those found in patients suffering from myxoedema and thyrotoxicosis. The ratio allows a more precise selection of the borderline cases requiring Thyroid Stimulating Hormone and triiodothyronine assays, particularly when the serum TBG is raised or lowered. 相似文献
44.
Detailed electronic description of triple bonds between transition metal atoms and verification by photoelectron spectroscopy 下载免费PDF全文
45.
In the UK, recent guidance on supportive and palliative care has acknowledged the contribution of voluntary organizations, including their role in palliative day care. Similarly, research has tended to focus exclusively on palliative day care as opposed to comparable care for people with cancer, regardless of prognosis. This paper describes a case record review study conducted at a nurse-led voluntary sector cancer day care centre. The study focused on referrals over a one-year period in terms of user demographics, referral sources/reasons and subsequent care given. It was found that 220 referrals (including 106 self-referrals) were made during the year. Of these, 70.9% were people with cancer and the remainder were carers/bereaved people. Those referred broadly reflected national statistics on age, gender and cancer diagnosis. Carers were rarely referred by professionals, few lived in inner-city neighbourhoods and some had no informal support. Non-specific referral reasons, such as 'support', tended to be translated into specific therapies, such as complementary therapies and counselling, at initial assessment. Care offered at the centre appeared to supplement and complement that provided by local statutory services. The study raised issues for practice and further research that may be relevant to those working in similar centres. 相似文献
46.
Ho GT Seddon AJ Therapondos G Satsangi J Hayes PC 《European journal of gastroenterology & hepatology》2005,17(12):1379-1385
BACKGROUND AND AIMS: The course of ulcerative colitis (UC) following orthotopic liver transplantation (OLT) for primary sclerosing cholangitis (PSC) is unclear. We documented the nationwide experience of the course of UC, before and after OLT for PSC. METHODS AND RESULTS: A total of 470 liver transplants were performed for 413 patients between 1992 and 2003, in the Scottish Liver Transplantation Unit, UK. Twenty-six patients had co-existing UC/PSC. Of these, data from 20 patients were studied over a median period of 11.9 years before OLT and 4.4 years after OLT; of the others, four patients required colectomy prior to OLT, one died within 7 days of transplant, and one developed UC after transplant. A significantly higher relapse rate (number of relapses/year of follow-up) was seen after OLT (median 1.0 versus 0.3; interquartile range, 0.10-1.42 and 0.01-0.40, respectively; P = 0.007). The corticosteroids requirement (number of courses/year of follow-up) after OLT was also significantly higher (0.40 versus 0.10; interquartile range, 0.51-1.13 and 0.05-0.12, respectively; P = 0.003). Twenty per cent of patients (4/20) became corticosteroid dependent after OLT. Thirty-five per cent of patients (7/20) underwent colectomy after OLT: three for severe disease and four for neoplasia/dysplasia. Five patients (19%) developed neoplasia following OLT. CONCLUSION: Despite immunosuppression, UC follows a more aggressive clinical course after OLT and is associated with a high rate of neoplasia. 相似文献
47.
This biographical note outlines the work of Sir William Jenner (1815-1898), court physician 1861-93 and President of the Royal College of Physicians 1881-8. He was the first to distinguish between typhoid and typhus both clinically and pathologically. 相似文献
48.
Chavasse RJ Bastian-Lee Y Richter H Hilliard T Seddon P 《Archives of disease in childhood》2000,82(5):370-375
BACKGROUND—Salbutamol is frequently used as a bronchodilator for infants who wheeze. Many single dose studies have questioned its effectiveness.AIMS—To investigate the response of wheezy infants to salbutamol over an extended time period in order to elucidate either symptomatic relief or a protective effect.METHODS—Eighty infants under 1 year, with persistent or recurrent wheeze and a personal or family history of atopy, were recruited to a randomised, double blind, cross over, placebo controlled trial. Salbutamol (200 µg three times daily) or placebo were administered regularly over two consecutive treatment periods of four weeks via a spacer and mask. Symptoms of wheeze and cough were recorded in a diary. At the end of the study pulmonary function tests were performed before and after salbutamol (400 µg).RESULTS—Forty eight infants completed the diary study; 40 infants underwent pulmonary function testing. No difference in mean daily symptom score was observed between the salbutamol and placebo periods. There was no difference in the number of symptom free days. Compliance and forced expiratory flows remained unchanged and resistance increased following salbutamol. There was no relation between the response measured by symptom score or pulmonary function in individual patients.CONCLUSION—In wheezy infants with an atopic background, there was no significant beneficial effect of salbutamol on either clinical symptoms or pulmonary function. Clinical effects could not be predicted from pulmonary function tests. Salbutamol cannot be recommended as the bronchodilator of choice in this age group. 相似文献
49.
Molecular characterization of human factor XSan Antonio 总被引:1,自引:0,他引:1
Enzymatic amplification technique was used to isolate all eight exons and sequences around the splice junctions, putative promoter, and polyadenylation sites of human factor X DNA from a patient with factor X deficiency. Two genetic changes in factor X have been observed in this patient. The patient is most likely a compound heterozygote since there is only 14% activity associated with factor X. A point mutation that resulted in the substitution of cysteine (TGC) for arginine (CGC) at amino acid 366 was found in exon VIII of one allele of the factor X gene. This mutation, which occurs in the catalytic domain, can affect the formation of a disulfide bridge and thus could result in a reduction in factor X activity. Sequencing all the regions revealed a second mutation: a deletion of one nucleotide (TCCT to TCT) in exon VII that would cause a frame shift at amino acid 272 followed by termination. We have also shown that the point mutation in exon VIII creates an ApaL1 restriction site and destroys the HinP1 site. Enzymatic DNA amplification followed by restriction digestion provides a quick, reliable, and sensitive method for carrier detection and antenatal diagnosis in affected kindreds. This is the first characterization of factor X deficiency at the molecular level. We propose to name this mutation Factor XSan Antonio. 相似文献
50.
Surgery remains the treatment of choice for massive and recurrent hemoptysis. In some instances, however, immediate surgical intervention is contraindicated. In these situations, bronchial artery embolization (BAE) has proved to be a successful definitive treatment for non-surgical candidates and a palliative therapy in patients requiring hemodynamic stabilization prior to surgery. The most serious complication of BAE is spinal cord ischemia. This relates directly to the potential anastomotic connections between the bronchial circulation and the anterior spinal artery. Somatosensory evoked potentials (SSEPs) have been used in the past to monitor spinal cord ischemia during procedures that threaten the vascularity of the spinal cord. The authors report two cases in which SSEPs were employed to monitor spinal cord ischemia during bronchial artery embolization. 相似文献