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991.
This is a community-based population survey carried out by the Yang-Ming Crusade to investigate the impact of years since menopause on the development of glucose intolerance in post-menopausal women. A total of 5412 women were screened with fasting plasma glucose. Those with fasting plasma glucose levels between 5.5 and 7.8 mM were given an oral glucose tolerance test. Among the 5412 women screened, 2039 (37.7%) were post-menopausal with a median age at menopause of 49 years. Pre-menopausal women showed impaired glucose tolerance (IGT) and diabetes mellitus (DM) prevalences of 3.7% and 3.1% respectively, whereas the corresponding figures for post-menopausal women were 8.4% and 17.6%, respectively. Comparing DM versus normal glucose tolerance (NGT) and IGT versus NGT as dependent variables in logistic regression analysis, menopause status was significantly associated with DM and IGT. In post-menopausal women, after maintaining body mass index, waist-hip ratio, systolic blood pressure, diastolic blood pressure, family history of DM, age at menopause, cholesterol, high density lipoprotein cholesterol and triglycerides as controls, years since menopause was the only significant factor associated with IGT (OR = 1.05, 95%CI 1.01-1.08) and years since menopause was not associated with DM. Further analysis indicated years since menopause (OR = 1.06, 95%CI, 1.01-1.11) was the only factor significantly associated with IGT for women whose age at menopause was greater than 49 years. Our study indicates that in subjects who have not undergone hormone replacement therapy and whose age at menopause is greater than 49 years, an increase in years since menopause confers a negative influence on glucose tolerance and increases the risk of IGT by 6% for each year after menopause.  相似文献   
992.
Finite element (FE) analysis has been utilised as a numerical tool to determine the temperature distribution in studies of radio frequency (RF) cardiac ablation. However, non of the previous FE analyses clarified such computational aspects as software requirements, computation time or convergence test. In addition, myocardial properties included in the previous models vary greatly. A process of FE modelling of a system that included blood, myocardium, and an ablation catheter with a thermistor embedded at the tip is described. The bio-heat equation is solved to determine the temperature distribution in myocardium using a commercial soft-ware application (ABAQUS). A Cauchy convergence test (∈=0.1°C) was performed and it is concluded that the optimal number of elements for the proposed system is 24610. The effects of changes in myocardial properties (±50% electric conductivity, +100%/−50% thermal conductivity, and +100%/−50% specific heat capacity) in both power-controlled (PCRFA) and temperature-controlled RF ablation (TCRFA) were studied. Changes in myocardial properties affect the results of the FE analyses of PCRFA more than those of TCRFA, and the maximum changes in lesion volumes were −58.6% (−50% electric conductivity), −60.7% (+100% thermal conductivity), and +43.2% (−50% specific heat).  相似文献   
993.
994.
OBJECTIVE: To compare the empty zona pellucidae (ZP) of different species for use in the cryopreservation of spermatozoa.Design: Prospective study. SETTING: An IVF unit of a medical center. Patient(s): Patients with azoospermia, oligoasthenozoospermia, or normal spermatozoa. INTERVENTION(s): Human and mouse ZP were prepared by evacuating the cytoplasm of oocytes or embryos. The evacuated ZP were injected with spermatozoa from patients with severe oligoasthenozoospermia and from healthy, fertile men. After the freezing and thawing procedure, the spermatozoa were aspirated outside the ZP. MAIN OUTCOME MEASURE(s): The number of spermatozoa per ZP, the number of motile sperm before freezing and after thawing, the number of sperm lost per ZP after freezing, and the sperm recovery rate were compared according to the different origins of the ZP and the sperm. RESULT(s): The number of spermatozoa, number of motile sperm before freezing and after thawing, number of sperm lost per ZP, and sperm recovery rate were comparable in all groups. The total mean number of motile sperm before freezing and after thawing, the mean number of nonmotile sperm after thawing, the mean number of sperm lost after thawing, and the sperm recovery rate were 14.5%, 11. 8%, 1.0%, 1.5%, and 82%, respectively. CONCLUSION(s): Zona pellucidae are an ideal vehicle for the cryopreservation of sperm collected by testicular sperm extraction or microsurgical epididymal sperm aspiration or from patients with severe oligoasthenozoospermia. There were no differences when human and mouse ZP were used for sperm storage.  相似文献   
995.
The anticipation phenomenon is an important aspect in several genetic disorders in which the age at onset (AAO) decreases and the severity of illness increases in successive generations. This phenomenon has been reported in several schizophrenic family studies, and expanded repeat mutations are implicated. In the present study, we investigate the anticipation phenomenon in Chinese schizophrenic families. We compare the AAO between two generations of 38 unilinear schizophrenic families. Intergenerational comparisons show that the AAO was significantly earlier in the offspring generation (mean AAO, 22.2 years) than that in the parental generation (mean AAO, 31.0 years) (P < 0.001). When only including the offspring generation who married, the AAO difference between the two generations was not significant (28.4 years vs 31.0 years, P = 0.151). Our findings suggest that a selection bias in the parental group might greatly impact the study of anticipation in schizophrenia. Other unavoidable biases associated with these analyses are discussed in the text.  相似文献   
996.
Lee BF  Chiu NT  Wu DC  Tsai KB  Liu GC  Yu HS  Wang ST 《Radiology》2001,220(2):381-385
PURPOSE: To evaluate the potential use of technetium 99m (99mTc) (V) dimercaptosuccinic acid (DMSA) scintigraphy in the detection and localization of intestinal inflammation. MATERIALS AND METHODS: In a prospective study, 62 patients who were suspected of having intestinal inflammation and 30 control subjects were enrolled. All patients underwent 99mTc (V) DMSA scintigraphy and colonoscopy with biopsy within 1 week. 99mTc (V) DMSA scintigrams were interpreted blindly with respect to clinical information, and radiotracer uptake in the bowel segments was graded. The findings were then compared with the results of the colonoscopy and colonoscopic biopsy. RESULTS: In the detection of intestinal inflammation, findings at 99mTc (V) DMSA scintigraphy were as follows: true-positive in 55, false-positive in two, true-negative in 32, and false-negative in three. Overall sensitivity was 95%; overall specificity, 94%; and overall accuracy, 95%. CONCLUSION: Our results show that 99mTc (V) DMSA scintigraphy is a useful noninvasive diagnostic test for the detection and localization of intestinal inflammation.  相似文献   
997.
998.
999.
The aim of this study is to examine extraction socket implant longevity and peri-implant conditions longitudinally and to compare the outcome with implants placed in intact alveolar bone sites (nonextraction sites) after a time period in function of five years or more. We hypothesize that implants placed into fresh extraction sockets have a long-term rate of success similar to that of conventionally placed implants. Eleven extraction socket implants in eight patients with a follow-up of at least five years were included in this report. The implants were loaded with either single-tooth replacements or three-to-four-unit fixed partial dentures after healing times of four to six months. Intraoral radiographs of the 11 implants were obtained immediately after surgery and upon recall five to seven years after surgery. In addition, the following clinical parameters were evaluated at each implant site five to seven years postsurgery: plaque indices (PT), bleeding indices (BI), probing depths, attachment level (AL), and distance from implant shoulder to mucosal margin (DIM). As a control, 11 implants from a previous long-term study of nonsubmerged implants placed into intact alveolar bone sites by the same clinician were matched by implant location, sex, and age. Initial and long-term follow-up radiographs of the experimental and control groups were scanned into a computer. A computer program designed for radiographic implant analysis was utilized to examine the changes in radiographic bone levels over time in the two groups. After a period of five to seven years, the mean bone loss for the immediate implant group was 0.167 mm, while that of the control group was 0.460 mm. An unpaired t-test resulted in a P value = 0.0563, indicating that the mean change in bone levels between the two groups is not statistically significant. In addition, clinical evaluation parameters (PI, BI, AL, DIM) revealed no significant difference between the two groups. Therefore, it can be stated that in this study the long-term success rate for extraction socket implants is similar to that of conventionally placed implants.  相似文献   
1000.
OBJECTIVE: To define the magnitude of spontaneous cardiac output variability over time in sedated medical intensive care unit patients attached to a continuous cardiac output monitor, and to determine whether high level positive end-expiratory pressure or inverse inspiratory-to-expiratory (I:E) ratio ventilation resulted in greater variability over time than low positive end-expiratory pressure with conventional I:E ratio ventilation. DESIGN: Prospective study. SETTING: Medical intensive care unit in a tertiary medical center. PATIENTS: A total of 22 hemodynamically stable acute respiratory failure patients with a pulmonary artery catheter inserted for hemodynamic monitoring INTERVENTIONS: After being sedated, patients were randomized ultimately to receive pressure control ventilation first at setting A (high positive end-expiratory pressure [15 cm H2O] with conventional I:E ratio [1:2]) and then at setting B (low positive end-expiratory pressure [5 cm H2O] with inverse I:E ratio [2:1]), or vice versa, and then at setting C (low positive end-expiratory pressure [5 cm H2O] with conventional I:E ratio [1:2]). Each ventilation setting period lasted 1 hr. MEASUREMENTS AND MAIN RESULTS: Cardiac output (CO) was measured continuously. The continuous CO value displayed was updated every 30-60 secs. The updated value reflected an average of the previous 3-6 mins. The coefficient of variation (CV) of CO for each setting in each patient was calculated to represent the spontaneous variability. The mean CO+/-SD and CV of each setting was 5.7+/-1.8 L/min and 4.4% for setting A, 5.6+/-1.5 L/min and 4.6% for setting B, and 5.9+/-1.7 L/min and 4.8% for setting C. Analysis of variance revealed no significant differences between the CVs of the three settings. The 95% confidence interval for the COs for each setting was approximately the mean CO+/-0.1 x mean CO measured. CONCLUSIONS: In critically ill sedated medical intensive care unit patients with stable hemodynamics, the spontaneous variability of cardiac output over time was not significant. High positive end-expiratory pressure (15 cm H2O) and inverse ratio ventilation (2:1) did not contribute to increased spontaneous variability of cardiac output.  相似文献   
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