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971.
Cystic islet cell tumors of the pancreas are extremely rare. The authors report their personal experience with two cases of nonfunctioning cystic endocrine neoplasms. The tumor was diagnosed preoperatively in one case by ultrasonography (US)-guided fine-needle aspiration cytology, while in the other it was identified only in the surgical specimen after a clinical-radiologic diagnosis of pancreatic mucinous cystic tumor. Immunohistochemical assay showed positivity for the generic neuroendocrine markers (neuron specific enolase, or NSE, synaptophysin, and chromogranin A) in both cases and also for glucagon in one case. The neoplasms were resected by distal pancreatectomy with splenectomy and intermediate pancreatectomy respectively. Both patients are alive and recurrence-free 6 mo and 2.5 yr, respectively, after surgery. The authors also review the existing literature, discussing the pathogenesis of such tumors and the imaging techniques and surgical strategies adopted in their management.  相似文献   
972.
OBJECTIVES: Fertility rates in women with congenital adrenal hyperplasia (CAH) are reported to be poor, but few data are available. We assessed rates and course of pregnancy, mode of delivery and long-term outcome of offspring from women with CAH. DESIGN: A large cohort of women with CAH due to 21-hydroxylase deficiency had initially been diagnosed and followed at one centre. Those women who had given birth were contacted. Information was gathered from hospital records, direct patient contact, structured questionnaire and the Documentation of Pregnancy and Preventive Care Booklets. RESULTS: Between 1978 and 1998, 18 women with CAH (one salt wasting, 12 simple virilizing, five nonclassical) had given birth to 31 children (18 females, 13 males). Delivery was by Caesarean section in 16 out of the 31 children. None of the female newborns was masculinized. Twenty-nine children were born at term, five children were small for gestational age (SGA). Postnatal development was basically normal in all children; 18 are now older than 10 years, seven are between 5 and 10 years old, six are less than 5 years old. CONCLUSIONS: Fertility is reduced in females with CAH, especially those with the severe or salt wasting phenotype. In those women with CAH who do conceive, course and outcome of pregnancy is mostly uneventful, although the rate of SGA offspring may be increased. Psychomotor and somatic long-term development of the children was within normal limits.  相似文献   
973.
Several studies have shown a relationship between blood pressure (BP) and cognitive function. Yet very few studies have addressed circadian BP patterns in this context, perhaps due to poor availability of suitable methods to detect slight changes in the cognitive state. Today, brain event-related potentials (ERPs) allow us to detect subclinical changes in cognitive function. We enrolled 30 elderly patients with recently diagnosed hypertension (<2 years) that had never been treated: 18 dippers and 12 nondippers. Patients underwent 24-h ambulatory blood pressure monitoring (ABPM). Careful assessment of their cognitive state was carried out using the mini mental state examination (MMSE), and the recording of P300 and N2 ERPs. No significant differences between the two groups were found. MMSE scores in dippers and nondippers were similar (29.5+/-0.71 vs. 29.3+/-1.07, respectively; p =0.611), as were P300 latency values (377.78+/-33.28 vs. 364.67+/-35.12 in the central (Cz) position, p =0.310; 379.22+/-32.94 vs. 365.25+/-35.07 in the occipital (Pz) position, p =0.277) and N2 wave latency values (253.83+/-24.9 vs. 249.17+/-24.47 in the Cz position, p =0.617; 251.56+/-25.86 vs. 246.58+/-25.46 in the Pz position, p =0.608). These data show no association between the nondipping pattern and lower cognitive function in elderly subjects with recent hypertension.  相似文献   
974.
Opioid administration before surgical stimulus may reduce or prevent subsequent pain. We studiied the effect of timing of opioid administration on the pain-related behaviour after abdominal hysterectomy. Eighty-five patients scheduled for abdominal hysterectomy were blindly randomized to receive fentanyl 10 μg· kg?1 before induction of anaesthesia (FA), after peritoneal incision (FB) or after removal of the uterus (FC), or sufentanil 1 μg· kg?1 before induction of anaesthesia (SA) or after peritoneal incision (SB) respectively. All patients received a standard postoperative analgesic regimen. The time from skin closure to the first analgesic request was recorded. Pain was assessed using the VAS and a verbal rating score (VSR 1 =no pain to 6 = intolerable pain) every 30 min until patients asked for the first analgesic, and 24 hr postoperatively. The times from skin closure to the first analgesic request did not differ among the five groups. The VAS scores using the two-way ANOVA with repeated measurements differed among the five groups (F = 4.046, df = 4, 213, P < 0.005). The VAS scores with one-way ANOVA differed among the five groups 30 min postoperatively (F = 4.542, df = 4, 58, P < 0.003), being higher in the FA (6.5 ± 1.8) and SA (5.9 ± 2.1) groups than in the FC (3.2 ± 2.5) group, and at 120 min postoperatively (F = 3.217, df= 4, 18, P < 0.05), being higher in the FA than in the FB group (6.1 ± 7.5 and 2.6 ± 1.9 respectively). The VRS scores did not differ among the FA, FB, FC, SA and SB groups at any time. This study failed to demonstrate a preemptive effect of systemic administration of fentanyl or sufentanil in the doses tested.  相似文献   
975.
976.
The present study investigated the temporal processing abilities of college students with diagnosed reading disorders. A behavioral test battery was used that involved discrimination of the pattern of presentation of tone triads in which individual components differed in either frequency or duration. An additional test involving measurement of frequency difference limens for long- and short-duration tones was also administered. The college students with reading disorders exhibited significantly higher error rates in discriminating duration patterns than the normal reading group. No group differences were found for the frequency pattern discrimination task. Both groups exhibited larger frequency difference limens with the shorter 20- and 50-ms tones than with the 200-ms tones. Significant correlations were found between reading ability measures and temporal processing abilities, specifically in word recognition and duration pattern processing, suggesting a relationship between lower level auditory temporal processing skills and decoding efficiency.  相似文献   
977.
Purpose: Whether the gene expression of vascular endothelial growth factor (VEGF) in human granulosa cells is a predictor of fertilization was evaluated in patients participating in an in vitro fertilization program. Methods: Fifty patients with normal ovaries who were participating in an in vitro fertilization program at the University of Milan, San Raffaele Scientific Institute, were included in the study. We correlated E 2 and P serum levels on the day of oocyte collection, the number of follicles, oocytes collected, and fertilized, and pregnancies with mRNA for VEGF of luteinizing granulosa cells obtained at the time of oocyte retrieval. Results: Comparing E 2 and P serum levels, the number of follicles, oocytes collected and fertilized, and pregnancies with gene expression for VEGF, we found a positive correlation. E 2 and P serum levels were higher in patients with increased VEGF (P < 0.01). Furthermore, there were more follicles, oocytes collected and fertilized, and pregnancies in patients with maximum expression of VEGF, and the difference was statistically significant (P < 0.05). Conclusions: Our results suggest that VEGF may be important for vascular development during follicular growth and luteal differentiation, oocyte maturation, and fertilization.  相似文献   
978.
PURPOSE: Mitochondria are highly susceptible to oxidative damage. Although mitochondrial function decreases with oxidative damage, overall mitochondrial DNA (mtDNA) content increases to compensate for general mitochondrial dysfunction. We performed quantitative polymerase chain reaction for genes specific to mitochondrial and nuclear genomes to investigate relative mitochondrial abundance in a spectrum of dysplastic head and neck lesions. EXPERIMENTAL DESIGN: DNA from mild, moderate, and severe dysplasias, as well as invasive tumors and normal mucosal cells, was extracted. Using quantitative polymerase chain reaction, mitochondrial to nuclear DNA ratios were determined by quantification of cytochrome c oxidase subunit 1 (CoxI) and beta-actin genes. RESULTS: Mean CoxI/beta-actin DNA ratios for mild, moderate, and severe premalignant lesions were 0.0529, 0.0607, and 0.1021, respectively. The mean ratio for the normal mucosal cells contained in saliva was 0.0537, whereas the mean ratio for tumors was 0.1667. As a whole, our experimental model demonstrated significance (P = 0.0358). Comparisons between individual categories showed borderline significance when compared with the normal group, with P values of 0.0673, 0.0747, and 0.0824 for moderate and severe dysplasia and invasive tumor, respectively. CONCLUSIONS: Head and neck squamous cell carcinomas arise through premalignant intermediates and may be merely morphologic manifestations of accumulated genetic alterations. In keeping with this molecular tumor progression model, our study shows that mtDNA increases according to histopathologic grade, a phenomenon that may be a feedback mechanism that compensates for a generalized decline in respiratory chain function. Therefore, high mtDNA content may be another marker of genetic alteration, a measure of relative DNA injury, and a surrogate measure of histopathologic grade.  相似文献   
979.
980.
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