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81.
Ahr A Scharl A Lütke K Staszewski S Kacer PZ Kaufmann M 《Cancer Detection and Prevention》2000,24(2):179-185
Cervical intraepithelial neoplasia (CIN) is common in patients positive for human immunodeficiency virus (HIV). The questions are whether the management of CIN in these patients should be different from that of HIV-negative women, whether there are any prognostic factors to indicate the course of CIN, and whether the latter is influenced by antiretroviral therapy. A total of 267 HIV-seropositive women were counseled and examined in our colposcopic clinic. Of that number, 53 patients died during the observation period; 74% of these patients were immunosuppressed (CD4 count < 200 cells/mm3), and 45% were given diagnoses of CIN. The incidence of CIN was significantly higher in patients with CD4 less than 200 cells/mm3. Neither the route of HIV infection nor the HPV status nor smoking habits correlated with CIN. CIN relapse was histologically confirmed in 28% of patients who underwent complete surgical removal. Immune status plays an important role in HIV-positive women not only with respect to survival but with respect to CIN. 相似文献
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Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals. 相似文献
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PURPOSE OF REVIEW: In healthy individuals, upregulation of insulin secretion compensates for insulin resistance so that normal glucose tolerance is maintained. Thus insulin secretion should be evaluated in relation to insulin sensitivity, as failure to account for insulin resistance may prevent the detection of beta-cell defects. Numerous studies have considered this problem, but how insulin secretion is regulated by insulin sensitivity and how insulin secretion should be quantitatively expressed to account for sensitivity are issues still under debate. This review will discuss these concepts and the aspects that should be considered for an appropriate solution to the problem. RECENT FINDINGS: While the historical paradigm of a specific hyperbolic relationship between some particular insulin secretion and insulin sensitivity indices has recently been confirmed, it has been suggested that this paradigm is not applicable to all the indices. It has also been suggested that for some relevant insulin secretion indices this relationship may not exist. Thus, the classical insulin secretion index that accounts for sensitivity, the so-called disposition index, should be used cautiously, as it presupposes a hyperbolic relationship. Furthermore, it has been pointed out that the assessment of this relationship requires independency of the indices. SUMMARY: The assessment of insulin secretion in relation to insulin sensitivity is important in the study of glycemic control but requires appropriate methods and cautious interpretations. Blind application of principles that are valid for specific insulin secretion and sensitivity indices may produce false results. 相似文献
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LeRoy AJ; Williams HJ Jr; Bender CE; Segura JW; Patterson DE; Benson RC 《Radiology》1985,155(1):83-85
Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal. 相似文献
88.
Lipids may serve as coupling factors in K(ATP)-independent glucose sensing in beta-cells. We have previously demonstrated that beta-cells harbor lipase activities, one of which is the hormone-sensitive lipase. Whether beta-cell lipases are critical for glucose-stimulated insulin secretion (GSIS) by providing lipid-derived signals from endogenous lipids is unknown. Therefore, using a lipase inhibitor (orlistat), we examined whether lipase inhibition reduces insulin secretion. Islet lipolysis stimulated by glucose and diglyceride lipase activity was abolished by orlistat. Incubation of rat islets with orlistat dose dependently inhibited GSIS; this inhibition was reversed by 1 mmol/l palmitate, suggesting that orlistat acts via impaired formation of an acylglyceride-derived coupling signal. Orlistat inhibited the potentiating effect of forskolin on GSIS, an effect proposed to be due to activation of a lipase. In perifused islets, orlistat attenuated mainly the second phase of insulin secretion. Because the rise in islet ATP/ADP levels in response to glucose and oxidation of the sugar were unaffected by orlistat whereas the second phase of insulin secretion was reduced, it seems likely that a lipid coupling factor involved in K(ATP)-independent glucose sensing has been perturbed. Thus, beta-cell lipase activity is involved in GSIS, emphasizing the important role of beta-cell lipid metabolism for insulin secretion. 相似文献
89.
The high-fat diet-fed mouse: a model for studying mechanisms and treatment of impaired glucose tolerance and type 2 diabetes 总被引:1,自引:0,他引:1
This study characterizes the high-fat diet-fed mouse as a model for impaired glucose tolerance (IGT) and type 2 diabetes. Female C57BL/6J mice were fed a high-fat diet (58% energy by fat) or a normal diet (11% fat). Body weight was higher in mice fed the high-fat diet already after the first week, due to higher dietary intake in combination with lower metabolic efficiency. Circulating glucose increased after 1 week on high-fat diet and remained elevated at a level of approximately 1 mmol/l throughout the 12-month study period. In contrast, circulating insulin increased progressively by time. Intravenous glucose challenge revealed a severely compromised insulin response in association with marked glucose intolerance already after 1 week. To illustrate the usefulness of this model for the development of new treatment, mice were fed an orally active inhibitor of dipeptidyl peptidase-IV (LAF237) in the drinking water (0.3 mg/ml) for 4 weeks. This normalized glucose tolerance, as judged by an oral glucose tolerance test, in association with augmented insulin secretion. We conclude that the high-fat diet-fed C57BL/6J mouse model is a robust model for IGT and early type 2 diabetes, which may be used for studies on pathophysiology and development of new treatment. 相似文献
90.
Uterine contractility and directed sperm transport assessed by hysterosalpingoscintigraphy (HSSG) and intrauterine pressure (IUP) measurement 总被引:4,自引:0,他引:4
Kissler S Siebzehnruebl E Kohl J Mueller A Hamscho N Gaetje R Ahr A Rody A Kaufmann M 《Acta obstetricia et gynecologica Scandinavica》2004,83(4):369-374
BACKGROUND: Uterine peristalsis sustains sperm transport and can be detected by hysterosalpingoscintigraphy (HSSG). This study is the first to be designed to investigate utero-tubal transport function by HSSG and uterine contractility by intrauterine pressure measurement (IUP) consecutively on the same day in the periovulatory phase. METHODS: Twenty-one female subjects (mean age 28.4 years) without a gynecologic history were examined sequentially by HSSG and IUP on the same day to evaluate uterine contractility in relation to the utero-tubal transport function. In HSSG, intact transport function was visualized by the rapid uptake of 99m-technetium-marked albumin aggregates through the female genital tract. In IUP, the frequency of uterine contractions (UC/min), amplitude of uterine contractions and basal pressure tone were detected via a intrauterine catheter. HSSG and IUP were embedded in cycle monitoring with measurement of LH and estradiol. RESULTS: In HSSG, a positive transport of inert particles was assessed in 20 of 21 subjects, in 76% to the side of the dominant follicle or on both sides of the oviduct, and in 19% a strict contralateral transport could be observed. In only one subject (5%), no transport was assessed. The mean value of uterine contractions was 3.4 UC/min (SD +/- 0.7), the mean amplitude was 12.0 mmHg (SD +/- 4.25 mmHg). Basal pressure tone was 70.7 mmHg. There was a statistically significant correlation with estradiol levels: none of the subjects with less than 3 UC/min showed an estradiol level higher than 100 pg/mL; nearly every patient (one exception) with more than 3 UC/min had an estradiol level higher than 100 pg/mL (p < 0.0001, Fisher's exact test). CONCLUSIONS: Intact periovulatory utero-tubal transport function can be documented by HSSG and is caused by directed uterine contractility, measured consecutively by IUP. Uterine contractility is influenced by rising estradiol levels. Directed uterine contractility and intact utero-tubal transport function are considered necessary for intact sperm transport, mainly to the side bearing the dominant follicle to maximize fertility. 相似文献