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31.
PET with (R)-[O-methyl-11C] metomidate ([11C] MTO) is an attractive method for the characterisation of adrenal masses discriminating lesions of adrenal cortical origin from noncortical lesions. [11C] MTO was prepared by the reaction of [11C] methyliodide with the corresponding free acid. Three purification methods have been compared. The method of choice uses preparative HPLC with a ready-to-use weak acidic solvent.  相似文献   
32.
BACKGROUND: In most examined populations the RET germline polymorphism S836S is found in about 3.6% of the normal population but in about 9% of patients suffering from sporadic C-cell hyperplasia or medullary thyroid carcinoma. The polymorphism S836S is thought to be involved in the development of sporadic medullary thyroid carcinoma. CASE PRESENTATION: We report a 48-year-old woman suffering from primary hyperparathyroidism (parathormone 121-166 pg/ml, normal <72), bilateral diffuse and nodular C-cell hyperplasia (calcitonin after pentagastrin administration 156 pg/ml, normal <4.6), and papillary thyroid carcinoma. Two commercial analyses of RET did not reveal any germline mutation within the known hot spots. However, sequencing revealed the presence of the RET polymorphism S836S. Following total thyroidectomy and removal of two hyperplastic parathyroid glands parathormone decreased to 51 pg/ml and calcitonin was no longer detected. CONCLUSIONS: The pathogenetic importance of the RET polymorphism S836S is still obscure. However, according to the published overrepresentation of the RET polymorphism S836S in patients suffering from apparent sporadic medullary thyroid carcinoma, it is conceivable that it also plays a role in multiglandular endocrine disease.  相似文献   
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Over a five-and-a-half-year period, there were 298 laboratory requests for urinary 5-hydroxyindoleacetic acid (5-HIAA). The clinical and laboratory associations of the 24 patients in which there were 43 urinary 5-HIAA 24-h collection results greater than the laboratory upper reference limit are detailed. Four were confirmed carcinoid tumours and two were phaeochromocytomas. Flushing was a prominent symptom in 46% and diarrhoea or altered bowel habit in 37%. Associated with the raised urinary 5-HIAA values were increased levels of 4-hydroxy-3-methoxymandelic acid and homovanillic acid in 14.3% and 21%, respectively, of those collections where the metabolites were requested. Diagnostic imaging was performed in 57%. While the specificity was 88%, 5-HIAA is relatively insensitive in the diagnosis of carcinoid tumours and a more widespread use of diagnostic imaging including isotope scanning with labelled metaiodo-benzylguanidine, vasoactive intestinal peptide and octreotide is suggested.  相似文献   
37.
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non-heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.

Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non-heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non-heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.

Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).

Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.  相似文献   

38.
Lung cancer is the most prevalent malignancy in western countries and most of the patients present at advanced stages, but single splenic metastasis is exceptional instead. We report on a case of a seventy-three-year old male presenting with non-hemoptoic productive cough, constitutional syndrome and pain in the left lower quadrant. Physical examination and complementary radiological and hystologycal procedures revealed the presence of an adenocarcinoma of the left lung with probable splenic metastasis. The patient underwent splenectomy, which confirmed the diagnose of splenic metastasis of lung adenocarcinoma and, secondly, lung resection was performed. Topics about lung cancer metastasis are discussed.  相似文献   
39.
The dermatologist's procedure was introduced in 1972 by employers' liability insurance funds in the industrial, agricultural and public sectors of Germany's statutory occupational accident insurance as a "procedure for early detection of occupational skin diseases". So far, it is still the most relevant tool for secondary prevention in occupational dermatology in Germany. According to the intention of this procedure, insured persons with a skin disease in which an occupational aetiology is suspected must be offered preventive measures and, if necessary, given appropriate treatment to avoid their losing their jobs. On the initiative of the Central Federation of Industrial Professional Associations (HVBG), a study group was set up in 1999 from among its membership in cooperation with the Working Committee of Occupational and Environmental Dermatology (ABD) and the Professional Organisation of German Dermatologists (BVDD) to improve on the efficiency of the "classic" dermatologist's procedure. The proposed "optimised" dermatologist's procedure is based on the assumption that early detection followed by competent and intensified skin protection and skin care will be successful in retarding or stopping the progression of occupational dermatoses, while later treatment is likely to be less effective. In October 2002, a pilot study started in Northwest Germany to establish by scientific evaluation whether the implementation of secondary protective measures is definitively better when the provisional "optimised" dermatologist's procedure is followed. The study results should allow detailed suggestions for an improved dermatologist's procedure before it is introduced nationwide.  相似文献   
40.
Projection radiographic techniques have been used in a standardized manner for decades for the diagnosis of conditions of the foot and ankle; the indications for them and the pattern of findings useful in the initial diagnosis and monitoring of the course are generally known to clinical radiology staff. Computed tomography has been introduced as an extension of the basic procedures performed for diagnosis in the ankle and the hindfoot. In the case of complex fractures, however, specialist experience is essential. CT is an easily accessible investigative procedure and is meanwhile economical and very powerful. Magnetic resonance imaging supplements the range of investigations in special cases when there are particular problems. Microfractures, findings indicative of inflammation and/or dystrophy and, in particular questions concerning the musculoligamentous support system are the situations in which such investigations are needed. Ultrasound has an additive value vis-à-vis magnetic resonance imaging and is an easily accessible and highly effective examination procedure both for the primary diagnosis and for serial monitoring. Financial constraints in the healthcare sector are increasingly limiting purely medical indications. Regardless of this development, the retention of projection radiography, computer tomography, and magnetic resonance imaging must be demanded for the initial diagnosis in the care of foot and ankle injuries. The earliest possible implementation of all these techniques for the initial diagnosis is the first step towards effective treatment. Cafrefully chosen and, if appropriate, complementary strategies are needed for monitoring of the course and for assessment.  相似文献   
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