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排序方式: 共有1419条查询结果,搜索用时 15 毫秒
1.
Nawf Sharief Judith E. Kingston Vanessa M. Wright Kate Costeloe 《Pediatric hematology and oncology》1991,8(4):323-327
We describe a familial case of Marfan's syndrome with associated intrathoracic stomach detected during the neonatal period. The patient developed a primitive leukemia at 3 months of age. Acute leukemia in a patient with Marfan's syndrome has not previously been reported. 相似文献
2.
目的 探讨血管新生指标CD34、CD31、vWF、Ⅳ型胶原纤维及层粘连蛋白在肝细胞肝癌(HCC)中的表达及意义 ,同时比较上述几种血管新生因子与增殖细胞核抗原 (PCNA)、病理指标及预后的相关性 ,以便筛选出有效的临床预后指标。方法 采用免疫组化方法 ,对 5 3例肝细胞肝癌的标本进行CD31、CD34、vWF、Ⅳ型胶原纤维及层粘连蛋白的染色、计数 ,并用检测数据与患者的临床资料进行统计分析。结果 统计染色的血管面积后发现 ,CD34与多种临床病理指标无相关性 ;CD31与肝内门静脉浸润相关 ;vWF与肿瘤的TNM分期及肝内门静脉浸润呈正相关 ;CollⅣ与肝内门静脉浸润呈正相关、与术后生存期呈负相关 ;Lam与肝硬化及术中出血量呈负相关、与术后生存期呈正相关。PCNA与肿瘤TNM分期有关。结论 在HCC中 ,CollⅣ、vWF、及CD31为肝细胞肝癌的有效血管新生及预后指标 ;Lam则与肝硬化及术中出血相关 ;PCNA指数肿瘤分期有关 ;CD34不能用作血管新生或预后指标 相似文献
3.
Magnetic resonance imaging of foot and ankle trauma 总被引:2,自引:0,他引:2
MRI is a useful diagnostic tool in the assessment of traumatic lesions of the foot and ankle. It is especially useful in demonstrating acute and chronic tendon and ligament injuries. Subtle fractures, including osteochondral, nondisplaced, and stress fractures, are well shown with MRI but may be difficult to detect on radiographs. A bone scan may also be used to detect these fractures; however, with MRI the fracture extent may be determined. MRI is also useful in diagnosing complication of trauma, such as ischemic necrosis and bone and soft-tissue infections. 相似文献
4.
Protein components specifically associated with prespliceosome and spliceosome complexes. 总被引:40,自引:2,他引:38
We have carried out a systematic analysis of the protein composition of highly purified mammalian spliceosomes. We show that > 30 distinct proteins, including 20 previously unidentified components [designated spliceosome-associated proteins (SAPs)], are specifically associated with the spliceosome in a salt-resistant complex. In contrast to these spliceosome-specific proteins, we show that hnRNP proteins are not tightly associated with purified prespliceosome and spliceosome complexes. The splicing factor U2AF65, U1 snRNP-specific proteins, and several SAPs are present in the earliest prespliceosome complex (E). A set of 10 proteins is then added to the first ATP-dependent prespliceosome complex (A), and concomitantly, a significant decrease in the level of U2AF65 is observed. The fully assembled spliceosome is formed by the addition of 12 proteins in a reaction that requires ATP and both the 5' and 3' splice sites. 相似文献
5.
Lucille Kingston Dianne Reynolds Linda Paine Phillips 《Journal of Midwifery & Women's Health》1995,40(2):187-201
This article reviews the pertinent anatomy of each body system involved in the assessment of the head and neck (including the eyes, ears, nose, and throat) and describes the basic elements of the comprehensive health assessment. Frequently encountered chief complaints are discussed. Aspects of the health assessment that will assist the primary care provider in making a differential diagnosis and determining the need for referral are presented. This article is the first of two articles on this topic; the subsequent article will address primary care management of common conditions of the head and neck. 相似文献
6.
Retinoblastoma in Great Britain 1969-80: incidence, treatment, and survival. 总被引:7,自引:5,他引:2
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Patients with retinoblastoma diagnosed from 1969 to 1980 have been followed up for periods of up to 17 years. Data from a previous study of patients diagnosed from 1962 to 1968 have been included for analysis of incidence and second primary tumours, and for study of trends in treatment. The registration rate in Britain (which may be about 10% less than the true incidence) is about one in 23,000 live births, approximately 40% of cases being known to be genetic. There is no apparent trend in incidence during the period covered by these two studies. The three-year survival rate in 88%. Patients with bilateral tumours have a better survival rate than those with unilateral tumours for the first few years, but their long-term survival rate is worse because of later deaths from ectopic intracranial retinoblastoma or second primary neoplasms. Older children tend to have a worse prognosis, which is related to the fact that their tumours are diagnosed at a more advanced stage. There is a significantly higher survival rate for boys than for girls; this is partly accounted for by difference in age and stage at diagnosis between the sexes. Children referred to units specialising in the treatment of retinoblastoma have a higher three-year survival rate than those treated at other hospitals. Comparing methods of treatment between the periods 1962-8 and 1969-80, we find there has been a trend towards more conservative treatment. The use of chemotherapy is now usually reserved for recurrences and metastases and for palliative treatment in terminal retinoblastoma. 相似文献
7.
J L Hungerford N M Toma P N Plowman J E Kingston 《The British journal of ophthalmology》1995,79(2):109-111
A retrospective analysis has been performed of the results of external beam radiotherapy for retinoblastoma using a whole eye technique. Local tumour control has been assessed in a consecutive series of 175 eyes in 142 children all of whom received external beam radiotherapy as the primary treatment for retinoblastoma. Follow up ranged from 2 to 17 years (median 9 years). Tumour control rates have been analysed with respect to the Reese Ellsworth classification and the series includes eyes in groups I to V. Focal salvage therapy was given for persistent, recurrent, or new tumours after radiotherapy. Following whole eye radiotherapy alone, the overall ocular cure rate was 57%, though with salvage therapy 80% of eyes could be preserved. 相似文献
8.
Role of frozen section and clinical parameters in distinguishing benign from malignant follicular neoplasms of the thyroid. 总被引:2,自引:0,他引:2
The determination of malignancy preoperatively or intraoperatively is difficult in patients with follicular neoplasms of the thyroid. This study reviews a series of 395 patients treated for follicular neoplasms at the Vancouver General Hospital and the British Columbia Cancer Agency between the years of 1955 and 1988, 198 of whom had frozen section at the time of surgery. Frozen section was 79% accurate in differentiating follicular adenomas from carcinomas, with a sensitivity of 52% and a specificity of 100%. The positive predictive value of a frozen section showing carcinoma was 100%, and the negative predictive value was 73%. An incorrect diagnosis of a benign lesion was made in 21% of patients in whom the final diagnosis by fixed section was carcinoma. These same statistics were calculated for patients aged greater than 50 years, tumor size greater than 3 cm, and patients with a history of previous neck irradiation, three clinical factors shown in a previous study to be strong prognostic indicators of malignancy. The results were compared with those found by frozen section. The implications of these results in terms of patient management are discussed. 相似文献
9.
A. TSATSOULIS E. WHITEHEAD J. ST. JOHN S. M. SHALET W. R. ROBERTSON 《Clinical endocrinology》1987,27(6):683-689
Eighteen men (mean age 27, range 18-30 years) treated for Hodgkin's disease with 6-8 courses of MVPP (Mustine, Vinblastine, Procarbazine and Prednisolone) have had Leydig cell function assessed by their steroidogenic responses to stimulation by a single bolus dose of HCG (1000 units intramuscularly). Normal age-matched men (n = 16) acted as controls. Baseline immunoreactive FSH was markedly raised in the patients (mean 18.1 +/- SD 6.9 vs 2.0 +/- 1.5 IU/l, P less than 0.0001) reflecting damage to the germinal epithelium. Immunoreactive LH was also greater in patients (10.3 +/- 3.9 IU/l) than in controls (3.9 +/- 1.9 IU/l, P less than 0.0001). There were no differences between the baseline testosterone, androstenedione, oestradiol, oestrone and sex hormone binding globulin (SHBG) concentrations. The testosterone/SHBG ratios were similar in the two groups and there was no correlation between baseline LH and testosterone concentrations or testosterone/SHBG ratios. Testosterone, androstenedione, oestradiol and oestrone secretion in response to HCG stimulation were similar at 24 h and 96 h in both groups. In order to explain the paradox of elevated immunoreactive LH in the face of normal testicular steroidogenesis in such patients, LH biological activity (B) as well as LH immunoreactivity (I) and FSH and testosterone were estimated in a second similar group of patients (n = 17, mean age 27, range 17-43 years) and in a further age-matched control group (n = 17). Bioactive and immunoreactive LH levels were significantly increased (P less than 0.005 and P less than 0.001, respectively) in the patient group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
Membrane flow within the myelin sheath in IDPN neuropathy 总被引:1,自引:0,他引:1
A. E. BLAUROCK M. B. GENTER ST CLAIR D. G. GRAHAM 《Neuropathology and applied neurobiology》1991,17(4):309-321
This report describes some aspects of beta,beta'-iminodipropionitrile (IDPN) neuropathy in rats as observed by ultrastructural methods and X-ray diffraction. Light microscopy shows gross swelling of the axons in proximal lumbar spinal roots 8 days after intraperitoneal injection of IDPN. Mean axon cross-sectional area and mean axon perimeter increased to 280% and 160% of their control values, respectively. At the same time, myelin membrane packing was not visibly disturbed. In addition, X-ray diffraction patterns, recorded under physiological conditions, demonstrate that the myelin lipid bilayer thickness and widths of the aqueous spaces between bilayers did not change. Related observations are made on posterior tibial nerve (PNS myelin) and ventral spinal cord (CNS myelin). The various observations together are interpreted in terms of a fluid myelin membrane. It is proposed that the myelin membrane flows during axon swelling even though normal membrane-membrane contacts are maintained within the sheath. Membrane flow and slippage between membranes are explained in terms of a molecular model of the myelin multilayer. 相似文献