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Background and aims Insulinomas are rare endocrine disorders. Pre-operatively, conventional imaging techniques often fail to localise the tumor. In addition, due to the lack of quick insulin assays, intra-operative confirmation of complete resection was impossible until recently. Materials and methods Six patients with biochemical evidence of an insulinoma underwent pre-operative localisation studies and selective arterial calcium injection (SACI). In addition, insulin was measured before surgery and every 10–15 min after resection of the tumor using a quick insulin assay. Results Pre-operative localisation studies identified the tumor correctly as follows: endosonography: three of four, magnetic resonance imaging: two of four and SACI: six of six. Tumors in the head and body were enucleated while those in the tail were resected (n = 2, each). Those three patients, in whom magnetic resonance imaging and/or endosonography could localise the tumors pre-operatively, underwent laparoscopic surgery while the remaining three patients underwent open surgery. Intra-operatively, insulin dropped to normal levels within 20 min in all cases. After a follow-up of 0.8–3 years, all patients remained biochemically cured. Conclusions Pre-operatively, SACI appears to be a very sensitive localisation technique and may be most helpful in guiding the surgeon if conventional imaging techniques fail to localise the tumor. Complete removal of an insulinoma can be reliably predicted using a quick insulin assay. This paper was presented at the 2nd Biennial Meeting of the European Society of Endocrine Surgeons (ESES), May 18–20, 2006, Krakow, Poland.  相似文献   
74.
Background From the endocrine surgeon’s perspective, it is important to know how endocrinologists manage patients with primary hyperparathyroidism (pHPT). The aim of this survey was to evaluate the preoperative diagnostic workup and referral pattern for parathyroidectomy by Swiss endocrinologists. Materials and methods The survey was conducted by mailing a questionnaire to all members of the Swiss Society for Endocrinology and Diabetes in spring 2005. Results The questionnaire was sent back by 68 of 124 endocrinologists (55%). The median annual case volume of patients with pHPT was 6 (range 1–50). The mean fraction of these patients referred for surgery was 59 ± 24%. This fraction was significantly higher in the German-speaking part of Switzerland than in the French-speaking part (67 ± 21% vs 51 ± 27%). When considering surgery for asymptomatic pHPT, 62% of the endocrinologists rely routinely on the recommendations of the NIH consensus conference and 86% on the subsequent guidelines of the workshop in 2002. Sixty-seven percent of the endocrinologists routinely perform localization studies before possible referral for surgical exploration. Typically, they consisted of an ultrasonography of the neck (93%) and a 99mTc-MIBI scintigraphy (80%). The impact of the availability of a minimally invasive surgical procedure on the number of patients referred for surgery seems to be considerable. Sixty-one percent of the participants would expand the indication for surgery if the operation could be done by a limited surgical approach. Conclusions In a relevant fraction of patients with pHPT, endocrinologists still do not regard curative therapy as mandatory. Surprisingly, there are significant cultural differences concerning referral patterns to surgery between the German-speaking and the French-speaking parts of Switzerland. Minimally invasive procedures seem to lower the threshold for referral for surgical therapy. This work was presented at the 2nd Biennial Congress of the ESES, May 2006, Krakow, Poland.  相似文献   
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Abstract Whiplash injury of the cervical spine is a frequent issue in medical expertises and causes enormous consequential costs for motor insurance companies. Some authors accuse posttraumatic changes of alar ligaments to be causative of consequential disturbances, although biomechanical experiments achieve contradictory results and neuropsychiatric studies do not support this thesis. MRI provides excellent visualization of alar ligaments. However, signal alterations of alar ligaments must be differentiated from common normal variants. Functional MRI provides no diagnostic yield.   相似文献   
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OBJECTIVE: The efficacy of a low-protein diet in the secondary prevention of diabetic nephropathy is not established in patients with type 1 or type 2 diabetes mellitus. To determine whether a low-protein diet slows the decrease in glomerular filtration rate (GFR) and decreases the albumin excretion rate (AER) in diabetic patients with incipient and overt nephropathy, we performed a 2-year prospective, randomized controlled trial comparing the effects of a low-protein diet (0.8 g/kg/day) with a usual-protein diet. SETTING AND PATIENTS: The study was conducted in a University hospital and included 63 type 1 and type 2 diabetic patients with either incipient or overt nephropathy and mild renal failure (prestudy GFR, 80 +/- 20 mL/min). The primary outcome measures were decreased in GFR and 24-hour AER. RESULTS: In the low-protein-diet group, patients were younger (52 +/- 12 versus 63 +/- 9 years old) and more often were type 2 diabetic. During the follow-up period, according to dietary records the low-protein-diet group consumed 16% +/- 3% of total caloric intakes as compared with 19% +/- 4% in the usual-protein-diet group (P < .02), but 24-hour urinary urea excretions did not differ between the two groups. The 2-year GFR decrease was 7 +/- 11 mL/min in the low-protein-diet group and 5 +/- 15 mL/min in the usual-protein-diet group (P = not significant). AER did not increase significantly in the two diet groups during the follow-up period. Blood pressure and glycemic control were similar in the two groups all along the study. The decrease in GFR and AER were also similar in 6 compliant patients according to dietary records and to 24-hour urinary urea excretions from the low-protein-diet group and in 12 patients from the usual-protein-diet group. CONCLUSIONS: A 2-year low-protein diet did not alter the course of GFR or of AER in diabetic patients with incipient or overt nephropathy receiving renin-angiotensin blockers with strict blood pressure control.  相似文献   
77.
The present text deals with the relationship of muscle force and mass to bone mass and geometry in the developing skeleton of children and adolescents. Recent results of the last ten years are discussed with reflection on Harold Frost's 'mechanostat hypothesis'. Bone mass and geometry follow the development of body size and muscle force in children and adolescents. Thereby, bone is adapted to the tissue strain due to biomechanical forces. This process is modified by hormonal signals (i.e., estrogens and androgens). Therefore, the quantified relationship of muscle force to bone stability is a reasonable approach to distinguish between primary and secondary bone diseases. Primary bone diseases are characterized by a disturbed adaptation of bone to biomechanical forces. In contrast, secondary bone diseases show a correct adaptation of bone to loaded forces in combination with a decline of muscle force. Therefore, the 'Functional Muscle-Bone Unit' was introduced into the diagnostics of pediatric bone diseases. The ratio of two parameters--referred to bone strength on the one and to biomechanical forces on the other side--is a reasonable diagnostic approach to distinguish between primary and secondary bone diseases.  相似文献   
78.
The objective of this study was to investigate violent and nonviolent suicidal acts in men and women with severe depression. The records of 98 suicide victims, who had been admitted to the Department of Psychiatry, Lund University Hospital, Sweden between 1956 and 1969, were evaluated and the subjects were monitored up to 1998. The female group displayed a significant linear trend for nonviolent completed suicide after one suicide attempt, and even more significantly, after repeated attempts. A switch from only nonviolent suicide attempts to completed violent suicide was significantly more common in men than in women. These different progressions may contribute to the expected finding that men used violent methods for completed suicide more often than women.  相似文献   
79.
Nonlinear kinetics of imipramine in low and medium plasma level ranges   总被引:1,自引:0,他引:1  
Steady state plasma concentrations of imipramine and desipramine were studied at three to nine different imipramine dose levels in 17 extensive metabolizers of sparteine and at two dose levels in two poor metabolizers of sparteine, all treated for diabetic neuropathy symptoms. The imipramine doses were changed stepwise from doses yielding plasma concentrations of imipramine plus desipramine below 150 nM, up to doses yielding therapeutic drug levels of at least 300-500 nM. The imipramine doses required to achieve therapeutic drug levels was 20 or 25 mg/day in the two poor metabolizers and 50-350 mg/day in the extensive metabolizers. In the extensive metabolizers, the concentration/dose ratio increased for imipramine and desipramine with increasing dose. Dose adjustments based on a simple linear prediction from drug levels at initial dose (50 or 75 mg imipramine/day) thus would result in 0-130% (median, 20%) overestimates, most pronounced in patients with initial low steady state levels. The nonlinear kinetics of imipramine thus may be a significant clinical problem in patients treated for diabetic neuropathy symptoms.  相似文献   
80.
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