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991.
There is a recognized need for the early detection of gestational diabetes, and a single blood test, if reliable, would be advantageous. Because serum albumin and total protein are glycosylated and have short life spans, we investigated the usefulness of glycosylated albumin and glycosylated protein in the detection of gestational diabetes. We studied five groups, each with 20 subjects: nonpregnant and pregnant controls, nonpregnant and pregnant insulin-dependent diabetic (IDDM) patients, and gestational diabetic patients. All patients with no history of diabetes had an oral glucose tolerance test to define their carbohydrate status. Our results showed that percent glycosylated albumin and percent glycosylated protein were significantly elevated in both groups of IDDM patients compared with the other groups. However, gestational diabetic patients had glycosylated albumin and glycosylated protein values similar to those of both control groups. Both glycosylated albumin and glycosylated protein correlated well with HbA1c determinations. Thus, glycosylated albumin and glycosylated protein may be a good index of glycemic control, but they are of little value in the diagnosis of gestational diabetes because of a lack of sensitivity: 8 and 3% for glycosylated albumin and glycosylated protein, respectively. 相似文献
992.
Secretory antibodies protect mucosal surfaces against transmission of many viruses. Human T-lymphotropic Virus, Type I (HTLV-I) is transmitted via blood products and via sexual contact across mucosal surfaces. We investigated the presence of HTLV-I-specific antibodies in whole saliva samples from 10 seronegative and 28 seropositive volunteers from a hospital in southern Japan. Antibodies directed to HTLV-I antigens were found in the salivas from 22 of 28 (79%) of the seropositive subjects. None of the seronegative individuals showed evidence of salivary antibodies. Antibodies directed to the envelope antigens of the virus were found in 21 of 22 positive saliva samples. Secretory antibodies may be important in preventing mucosal transmission. 相似文献
993.
J Parinaud H Grandjean M F Sarramon J M Reme X Monrozies C Sarrazin G Pontonnier 《European journal of obstetrics, gynecology, and reproductive biology》1987,24(4):285-292
In order to ascertain the adequacy of ovarian stimulation protocols with a type of follicular puncture, 126 women undergoing in vitro fertilization received either combination clomiphene/hMG or hMG alone according to a randomized test protocol. Within both groups patients for whom a pelvic examination was required had laparoscopies, while others had transvaginal ultrasonically guided punctures as far as possible. Clomiphene/hMG was more efficient than hMG alone as assessed from the cleavage rate (68% vs. 54%; p less than 0.01) and the pregnancy per attempt rate (16% vs. 5%; p less than 0.05). Laparoscopic punctures were more efficient than ultrasonically guided punctures (mean number of recovered oocytes: 4.8 +/- 2.6 vs. 3 +/- 2.5; p less than 0.001), but slightly better results were achieved by this latter method in ongoing pregnancy per puncture rate (18% vs. 8%; NS). With ultrasonically guided punctures, stimulation by clomiphene/hMG allowed better oocyte recoveries (3.8 +/- 2.5 vs. 2.3 +/- 1.9, p less than 0.05). Such results constitute an argument for preferential use of the clomiphene/hMG stimulation protocol with ultrasonically guided punctures. 相似文献
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Stanford''s two decades of success in linking medical informatics and health services research in both training and investigational activities reflects advantageous geography and history as well as natural synergies in the two areas. Health services research and medical informatics at Stanford have long shared a quantitative, analytic orientation, along with linked administration, curriculum, and clinical activities. Both the medical informatics and the health services research curricula draw on diverse course offerings throughout the university, and both the training and research overlap in such areas as outcomes research, large database analysis, and decision analysis/decision support. The Stanford experience suggests that successful integration of programs in medical informatics and health services research requires areas of overlapping or synergistic interest and activity among the involved faculty and, hence, in time, among the students. This is enhanced by a mixture of casual and structured contact among students from both disciplines, including social interactions. The challenges to integration are how to overcome any geographic separation that may exist in a given institution; the proper management of relationships with those sub-areas of medical informatics that have less overlap with health services research; and the need to determine how best to exploit opportunities for collaboration that naturally occur.Training in medical informatics and health services research has been closely linked at Stanford University for almost two decades. Although the close linkage was deliberate, it was facilitated by historical circumstances, in particular the common academic structures in which both programs arose. In this paper, we describe some of that rationale and history, identifying the areas of overlap that we have pursued in coordinating the training opportunities for graduate students and fellows in both areas of study. As we shall note, the synergies have been great, and in some cases trainees have collaborated closely on research while also taking some of the same courses. We believe that these interactions can be a model for the design of training programs that encourage scholarly interactions between medical informatics and health services research. Although our initial charge was to describe both the successes and failures in integrating the programs, we found that we could not identify any outright failures and that it would be better to delineate the complexities and challenges that we have faced in bringing together these two disciplines. 相似文献
996.
997.
998.
999.
Symptoms of tobacco withdrawal. A replication and extension 总被引:19,自引:0,他引:19
Smokers (n = 315) who wished to quit were randomly assigned in a double-blind manner to groups using either nicotine or placebo gum. Self-reported and observed symptoms of tobacco withdrawal were collected before cessation and at follow-ups of 1 to 2 weeks, 1 month, and 6 months. Self-reported and/or observed anger, anxiety, craving, difficulty concentrating, hunger, impatience, and restlessness were the most prominent symptoms of tobacco withdrawal. These symptoms had returned to precessation levels by 1 month except increased weight, hunger, and craving continued for 6 months in many smokers. Nicotine gum decreased most symptoms, including craving and hunger but not weight. Abstinent smokers with more intense withdrawal were not more likely to relapse. Abstinent smokers who gained more weight were less likely to relapse. 相似文献
1000.
Valve-related complications with the Hancock I porcine bioprosthesis. A twelve- to fourteen-year follow-up study 总被引:4,自引:0,他引:4
J M Bernal J M Rabasa J C Cagigas J R Echevarria M F Carrion J M Revuelta 《The Journal of thoracic and cardiovascular surgery》1991,101(5):871-880
Valve-related morbidity and mortality after heart valve replacement with the Hancock I porcine bioprosthesis has been retrospectively analyzed. From June 1974 through December 1976, 253 Hancock I bioprostheses (150 mitral and 103 aortic) were inserted in 220 selected patients who survived the operation and had follow-up until June 1989 (mean follow-up 13.5 years, with an accumulative follow-up of 2956.4 patient-years). One hundred seventeen patients had mitral valve replacement, 70 had aortic valve replacement, and 33 had combined mitral and aortic valve replacement. There were 27 thromboembolic events. The probability of being free from thromboembolism at 14 years was 81.0% +/- 7.4% for the mitral valve replacement group, 85.4% +/- 6.7% for the aortic group, and 67.1% +/- 18.4% for the mitral-aortic group. Fifteen episodes of prosthetic valve endocarditis occurred. There were 10 instances of nonstructural dysfunction (paravalvular leaks) in seven mitral valves (4.6%) and in three aortic valves (2.9%). One hundred twenty-two bioprostheses in 106 patients resulted in structural deterioration. The probability of freedom from structural deterioration at 14 years was 37.2% +/- 3.9% for the mitral group, 43.9% +/- 7.1% for the aortic group, and 30.1% +/- 8.9% for the mitral-aortic group. The logistic regression analysis between age at the time of operation and bioprosthetic life (structural deterioration-free period) demonstrates a linear regression curve (r = 0.53). There were 56 late deaths (27 patients died at reoperation). The actuarial survival rate (including hospital mortality) at 14 years was 57.2% +/- 5.4% for the entire series, with no statistically significant difference between groups. The probability of remaining free from valve-related morbidity and mortality at 14 years was 16.7% +/- 4.8% for the mitral group, 20.8% +/- 6.2% for the aortic group, and 14.0% +/- 7.0% for the mitral-aortic group. The long-term results of this series show that the clinical performance of the Hancock I porcine valve appears satisfactory during the first 6 years. The behavior of this bioprosthesis at 14 years' follow-up changes drastically, because only a minor group of patients is free from valve-related complications, justifying the restriction of its use for selected patients. 相似文献