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LH as a diagnostic criterion for polycystic ovary syndrome in patients with WHO II oligo/amenorrhoea
Hendriks ML Brouwer J Hompes PG Homburg R Lambalk CB 《Reproductive biomedicine online》2008,16(6):765-771
Elevated LH is common in polycystic ovary syndrome (PCOS), but is not part of the diagnostic criteria. LH concentrations are usually assessed in the early 'follicular' phase when it is suppressed, and therefore the prevalence is underestimated. In this study, LH is measured during the 'specific oligomenorrhoeic phase', when LH is least suppressed, and its importance as a diagnostic tool for PCOS is evaluated. Patients presenting with oligo- or amenorrhoea between 2002 and 2006 were selected, with the exclusion of women with WHO III oligoamenorrhoea, hyperprolactinaemia or with wrongly timed endocrine measurements. A total of 252 patients were included (198 oligo/amenorrhoeic PCOS patients and 54 oligo/amenorrhoeic controls). Mean LH concentrations were higher in PCOS patients than in controls (11.0 versus 4.1 IU/l, P < 0.001). The receiver operating characteristics (ROC) curve showed an optimal cut-off for LH of > or =6.5 IU/l, resulting in a sensitivity of 84%, specificity of 78% and a likelihood ratio of 3.8, and elevated LH concentrations predicted PCOS accurately in 93%. In conclusion, elevated LH concentrations are found in a large majority of PCOS patients when measured at the appropriate time, and could be used as an additional diagnostic test to differentiate between oligo/amenorrhoeic PCOS patients and other causes of oligo- or anovulation. 相似文献
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Laura Koopman Lea G. Donselaar Jany J. Rademakers Michelle Hendriks 《Journal of clinical epidemiology》2013,66(3):340-348
ObjectiveTo find ways to improve response rates of medical and health surveys. We investigated whether a prenotification letter instead of a second reminder and varying senders of the questionnaires would affect response rates.Study Design and SettingWe present the results of two studies. In the first study, four groups were compared that either received a prenotification letter (group 1 and 2) or a second reminder letter (group 3 and 4); received the questionnaire from either a research institute (group 1 and 3) or a health insurance company (HIC; group 2 and 4). In the second study, we compared two groups that received the questionnaire sent by either a HIC or a hospital. Response rates, response speed, respondent characteristics, item nonresponse, and mean scores on quality aspects and global ratings were compared.ResultsResponse rates did not differ significantly between groups. Prenotification groups returned their questionnaires faster. No other significant differences were found for response speed, respondent characteristics, item nonresponse, or mean scores.ConclusionA prenotification letter does only increase initial response speed and does not increase total response rates. A prenotification letter should be considered when quick response is desirable. Varying senders had no effect on response rates. 相似文献
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Hendriks JM Van Schil PE Schrijvers D Van Marck E Eyskens E 《Acta chirurgica Belgica》1999,99(6):312-314
A 38-year-old patient presented with an anterior mediastinal mass after chemotherapeutic and surgical treatment for lung metastases from a malignant histiocytoma. Because of the risk for tumour recurrence the thymic mass was resected. Thymic hyperplasia was found on pathological examination. In this case thymic hyperplasia is a rebound phenomenon aflcer chemotherapy. It appears to atrophy during the administration of chemotherapy and regrow afterwards. Surgical resection provides the definitive diagnosis and treatment. 相似文献
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Kubosaki A Gross S Miura J Saeki K Zhu M Nakamura S Hendriks W Notkins AL 《Diabetes》2004,53(7):1684-1691
Insulinoma-associated protein (IA)-2beta, also known as phogrin, is an enzymatically inactive member of the transmembrane protein tyrosine phosphatase family and is located in dense-core secretory vesicles. In patients with type 1 diabetes, autoantibodies to IA-2beta appear years before the development of clinical disease. The genomic structure and function of IA-2beta, however, is not known. In the present study, we determined the genomic structure of IA-2beta and found that both human and mouse IA-2beta consist of 23 exons and span approximately 1,000 and 800 kb, respectively. With this information, we prepared a targeting construct and inactivated the mouse IA-2beta gene as demonstrated by lack of IA-2beta mRNA and protein expression. The IA-2beta(-/-) mice, in contrast to wild-type controls, showed mild glucose intolerance and impaired glucose-stimulated insulin secretion. Knockout of the IA-2beta gene in NOD mice, the most widely studied animal model for human type 1 diabetes, failed to prevent the development of cyclophosphamide-induced diabetes. We conclude that IA-2beta is involved in insulin secretion, but despite its importance as a major autoantigen in human type 1 diabetes, it is not required for the development of diabetes in NOD mice. 相似文献
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M G De Maeseneer C P Vandenbroeck J M Hendriks P R Lauwers P E Van Schil 《European journal of vascular and endovascular surgery》2005,29(3):308-312
OBJECTIVE: To investigate whether the results of duplex examination 1 year after sapheno-femoral junction (SFJ) ligation might be helpful in predicting long-term results after 5 years. PATIENTS AND METHODS: Follow-up data concerning patients operated on for primary or recurrent varicose veins of the great saphenous vein were studied 1 year and 5 years after surgery, focusing on the thigh and groin region. Clinical examination was undertaken to detect recurrent thigh varicose veins. The site of SFJ ligation was carefully screened for any signs of neovascularisation by duplex ultrasound. Sensitivity, specificity, positive and negative predictive value of the 1-year duplex scan were calculated, based upon the outcome of a further duplex scan 5 years following surgery. RESULTS: A total of 100 limbs were studied: 50 limbs operated on for primary varicose veins and 50 limbs for recurrent varicose veins. The 1-year duplex ultrasound of the SFJ ligation site had a sensitivity of 80%, a specificity of 91%, a positive predictive value of 70% and a negative predictive value of 95% in assessing the 5 year recurrence rate. CONCLUSION: A postoperative duplex scan of the SFJ 1 year after varicose vein surgery to the great saphenous vein predicts which patients are most likely to have a good outcome 5 years after surgery. The 1-year duplex scan is a reliable diagnostic tool for future studies evaluating the effect of new methods of treating sapheno-femoral incompetence. 相似文献
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L. A. E. Posma R. P. Bleichrodt R. M. L. M. Lomme B. M. de Man H. van Goor T. Hendriks 《Journal of gastrointestinal surgery》2009,13(6):1099-1106
Introduction During bowel surgery, perioperative blood loss and hypotension can lead to transient intestinal ischemia. Recent preclinical
studies reveal that the strength of intestinal anastomoses can be compromised after reperfusion. So far, this phenomenon has
not been investigated in the very first days of healing when wound strength is lowest.
Material and Method Ischemia was induced in rats by clamping both the superior mesenteric artery and ileal branches for 30 min. Immediately after
declamping, anastomoses were constructed in both terminal ileum and descending colon. The same was done in control groups
after sham-ischemia. Anastomotic bursting pressure and breaking strength were measured immediately after operation (day 0)
and after 1, 2, or 3 days. Anastomotic hydroxyproline content, gelatinase activity, and histology were analyzed.
Results and Discussion In ileal anastomoses, at day 1, both the breaking strength and bursting pressure were significantly (p < 0.05) lower in the ischemic group, while at day 2, this was the case for the bursting pressure only. In the colon, the
bursting pressure in the ischemic group was lower at day 1. Anastomotic hydroxyproline content remained unchanged. Increased
presence of the various gelatinase activities was found in ileum only at day 0 and in colon at days 1 and 2. Histological
mucosal damage was found in ischemia–reperfusion groups.
Conclusion Transient mesenteric ischemia can negatively affect anastomotic strength during the very first days of healing, even if the
tissue used for anastomotic construction looks vital. 相似文献
20.
M G De Maeseneer T E Philipsen C P Vandenbroeck P R Lauwers J M Hendriks S G De Hert P E Van Schil 《European journal of vascular and endovascular surgery》2007,34(3):361-366
BACKGROUND: Neovascularisation at the sapheno-femoral junction (SFJ) ligation site in the groin may occur within one year after great saphenous vein (GSV) surgery. Several anatomical and prosthetic barrier techniques have been proposed to prevent this evolution. OBJECTIVE: A prospective study examined whether closing the cribriform fascia could reduce the incidence of postoperative neovascularisation in the groin. PATIENTS AND METHODS: Patients with primary varicose veins and incompetence at the level of the SFJ were included. After SFJ ligation in 235 limbs of 193 patients an anatomical barrier was constructed by closing the cribriform fascia. Postoperative duplex scanning was performed after 2 and 12 months. Results were compared with historical control groups in which either a silicone patch saphenoplasty or no barrier technique had been performed. RESULTS: After one year, 10 limbs had developed recurrent thigh varicose veins and duplex scan showed neovascularisation at the SFJ ligation site in 15 of 223 re-examined limbs (6.7%). This was comparable to the group of 191 limbs with silicone patch saphenoplasty (5.2%) (P=0.526) and superior to the group of 189 limbs without barrier (14.8%) (P<0.01). CONCLUSION: Interposition of an anatomical barrier by closing the cribriform fascia after SFJ ligation reduced ultrasound detected neovascularisation at the SFJ after one year. In primary varicose vein operations application of an anatomical barrier technique (without prosthetic patch) is an alternative option to prevent postoperative neovascularisation. 相似文献