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排序方式: 共有553条查询结果,搜索用时 15 毫秒
31.
Rita G Harper Khalil U Rehman Concepcion Sia Sharon Buckwald Regina Spinazzola Jerrold Schlessel Judith Mestrandrea Mary Rodgers Raul A Wapnir 《Journal of perinatology》2002,22(7):555-562
OBJECTIVE: To assess if there have been changes in survival, demographic data, obstetric features, neonatal morbidity, and short-term neurologic/radiographic/neurosensory outcome of 500- to 800-g infants born in a tertiary care neonatal center from 1990 through 1998. STUDY DESIGN: Records of all 500- to 800-g infants born at North Shore University Hospital during 1990-1998 were reviewed to determine demographic data, survival by weight and gestational age (GA), obstetric features, neonatal morbidity, and short-term neurologic/radiographic/neurosensory outcome. Newborn infants were grouped into three triennia: 1990-1992, 1993-1995, and 1996-1998 and compared across time. RESULTS: Of the 173 infants admitted to the neonatal intensive care unit, 112 survived. Improved survival was documented: 40% in 1990-1992, 73% in 1993-1995, and 81% in 1996-1998 (p < 0.0001). Improved survival was also noted in each of the three weight cohorts, as well as in infants < or =26 weeks GA. An increased use of antenatal corticosteroids and increased number of deliveries by cesarean section (C/S) were noted across time. The incidence of 0 to 3 Apgar scores at both 1 and 5 minutes decreased across time. Necrotizing enterocolitis in survivors and expected short-term neurologic/radiographic/neurosensory outcome improved between 1990-1992 and 1996-1998, with a trend toward reduced IVH grade III to IV. The incidence of other neonatal morbidities did not change throughout the time period. CONCLUSIONS: The data document that survival rates continued to improve for 500- to 800-g infants throughout the 1990s. This was concurrent with an increase in "low-risk, expected normal" infants, increased number of deliveries by C/S, decreased incidence of low Apgar scores at both 1 and 5 minutes, and an increased use of antenatal corticosteroids. 相似文献
32.
A C/T single nucleotide polymorphism at the tyrosine kinase domain of the insulin receptor gene is associated with polycystic ovary syndrome 总被引:13,自引:0,他引:13
Siegel S Futterweit W Davies TF Concepcion ES Greenberg DA Villanueva R Tomer Y 《Fertility and sterility》2002,78(6):1240-1243
OBJECTIVE: To examine whether the insulin receptor (INSR) gene contributes to genetic susceptibility to the polycystic ovary syndrome (PCOS). DESIGN: Case-control study. SETTING: Academic endocrinology clinic. PATIENT(S): Ninety-nine women with PCOS as defined by the National Institutes of Health consensus and polycystic ovaries on ultrasonography, and 136 healthy controls. MAIN OUTCOME MEASURE: Frequency of genotypes of a single nucleotide polymorphism of the INSR gene in patients and controls. RESULT(S): After stratification of participants by body mass index, the frequency of the uncommon T allele of the INSR single nucleotide polymorphism was significantly increased in lean patients with PCOS (body mass index < or =27 kg/m2) compared with lean controls (relative risk, 2.1). CONCLUSION(S): The INSR gene is a susceptibility gene for PCOS among lean patients with PCOS. It remains to be determined whether the exon 17 C/T single nucleotide polymorphism is the susceptibility single nucleotide polymorphism for PCOS or whether it is in linkage disequilibrium with another INSR gene polymorphism. 相似文献
33.
Wurm WH Concepcion M Sternlicht A Carabuena JM Robelen G Goudas LC Strassels SA Carr DB 《Anesthesia and analgesia》2003,97(6):1620-1626
We performed a randomized, prospective, parallel-group, open-label, multicenter trial to compare the effects of pre- versus postoperative interscalene block using levobupivacaine on postoperative pain and analgesic requirements. One-hundred-two outpatients scheduled for elective shoulder surgery were randomized to receive 30 mL of 0.5% levobupivacaine either preoperatively (PRE group) or postoperatively (POST group). Analgesic outcome measures during the postoperative period were: (a). time to first request for analgesic medication after surgery, (b). pain intensity using the visual analog scale at rest and during arm movement, and (c). total analgesic consumption of nonsteroidal antiinflammatory drugs and opioids. The time to first analgesic request did not differ between treatment groups. However, mean maximum pain intensity scores during the day of surgery were significantly less for the PRE group than the POST group, both at rest (P = 0.001) and after movement (P = 0.004). The mean opioid administered during surgery was lower in the PRE than the POST group (P < 0.001). Levobupivacaine was well tolerated in both treatment groups, and no adverse reactions were related to this local anesthetic. In conclusion, preoperative interscalene block with levobupivacaine provided superior pain control for the first 12 h after surgery, but this benefit was not maintained during the week after discharge because the subjects assumed control of their own pain relief as outpatients. IMPLICATIONS: Preoperative interscalene block with levobupivacaine provides safe and effective analgesia for same-day elective shoulder surgery, but the benefit of this one-time intervention does not persist. 相似文献
34.
Prospective randomized study of bacteraemia in diathermy and stapled haemorrhoidectomy 总被引:5,自引:0,他引:5
Maw A Concepcion R Eu KW Seow-Choen F Heah SM Tang CL Tan AL 《The British journal of surgery》2003,90(2):222-226
BACKGROUND: The incidence and consequences of bacteraemia associated with diathermy and stapled haemorrhoidectomy have not been studied previously. METHODS: Two hundred and five healthy patients randomized to stapled haemorrhoidectomy or diathermy haemorrhoidectomy had perioperative blood cultures taken. The clinical sequelae of bacteraemia and complications of surgery were assessed prospectively. RESULTS: Six patients were excluded for protocol violations. Eleven (11 per cent) of 101 patients with stapled and five (5 per cent) of 98 who had diathermy haemorrhoidectomy had positive blood cultures for organisms after haemorrhoidectomy, predominantly anaerobes commonly found within the bacterial flora of the anorectum (P = 0.19). Transient postoperative pyrexia in several patients did not correlate with detected bacteraemia and settled spontaneously without treatment. There were no serious complications from either operative technique, and no clinical consequences from proven bacteraemia. CONCLUSION: Transient bacteraemia may complicate surgical haemorrhoidectomy but has no serious clinical consequences for healthy adults. 相似文献
35.
OBJECTIVES: To develop a scale that can assist in predicting likelihood of decline from mild dementia over 1 year in patients with Alzheimer's disease (AD). DESIGN: Retrospective cohort study. SETTING: University Memory and Aging Center. PARTICIPANTS: Patients with probable or possible AD and Clinical Dementia Rating (CDR) of 1 at baseline, divided into development and validation cohorts (n = 118 each). MEASUREMENTS: The CDR and neurological and neuropsychological assessments were given at baseline and 1 year later. RESULTS: In the development cohort, high education, low Mini-Mental State Examination score, poor insight, psychotic symptoms, and greater activity of daily living impairment predicted decline in CDR from 1 to 2 or 3. Receiver operating characteristics (ROC) curve analysis identified cutoff scores that maximized sensitivity and specificity for each significant predictor of decline. Based on the cutoff, raw scores were recoded to reflect risk for decline, weighted, and summed to create a final scale score. ROC curve analysis established a cutoff to indicate risk for decline on the final scale score. Sensitivity, specificity, and area under the ROC were 0.76, 0.74, and 0.83 in the development cohort and 0.77, 0.69, and 0.80 in the validation cohort, respectively. Positive and negative predictive values were 0.71 and 0.78 in the development cohort and 0.68 and 0.78 in the validation cohort, respectively. CONCLUSIONS: Decline from mild to moderate or severe impairment represents significant clinical change, with implications for patient and caregiver quality of life and treatment options. The clinical scale developed uses data to enhance prediction about change from mild to moderate or severe stages of AD. 相似文献
36.
37.
V Giandomenico F Andreola M L Rodriguez de la Concepcion S J Collins L M De Luca 《Carcinogenesis》1999,20(6):1133-1135
4-Hydroxyphenylretinamide (4-HPR) is a synthetic retinoid with minimal toxicity and favorable pharmacokinetics during long-term administration to patients in clinical trials. Since 4-HPR binds poorly to the retinoic acid receptors, the issue of whether 4-HPR exerts its biological actions via classical retinoid receptor pathways remains to be resolved. We have previously reported that stable expression of a truncated retinoic acid receptor alpha, RARalpha403, transduced in NIH 3T3 cells by a retroviral vector, rendered the cells resistant to retinoic acid for growth inhibition and induction of tissue transglutaminase (TGase II). Here, we report that stable expression of the dominant negative construct RARalpha403 fails to blunt growth inhibition and TGase II induction by 4-HPR, a potent chemopreventive retinoid, in the same cells. These data show that retinoic acid receptors do not mediate either growth inhibition or induction of TGase II activity by 4-HPR in mouse fibroblast cells. 相似文献
38.
Sierra-Torres CH Au WW Arrastia CD Cajas-Salazar N Robazetti SC Payne DA Tyring SK 《Environmental and molecular mutagenesis》2003,41(1):69-76
Infection with high-risk human papillomavirus (HPV) plays a major role in the etiology of cervical cancer (CC). However, most infected women do not develop cancer. Therefore, exposure to other carcinogenic agents may be a contributing risk factor for CC. We investigated the hypothesis that environmental exposure to cigarette smoke and inheritance of polymorphic chemical metabolizing genes (CYP2E1, GSTM1, and mEH) significantly increase the risk for neoplasia. We selected 76 cases with high-grade cervical neoplasia or with invasive CC and 75 matched healthy controls. The collected data support the well-established observation that infection with high-risk HPV is the major risk factor for CC (OR = 75; 95% CI = 26-220). In addition, our data show that women who smoked more than 15 "pack-year" had a significant 6.9-fold increase in risk (95% CI = 1.2-40.3) after adjustment for HPV infection. The CYP2E1 variant genotype did not significantly increase the risk for neoplasia. A significant increase in risk for neoplasia was observed for the low-activity mEH 113 His allele after adjustment for smoking (OR = 3.0; 95% CI = 1.4-6.3). The GSTM1 null genotype was associated with a significant 3.3-fold increased risk for neoplasia (95% CI = 1.0-11.8) compared to women who were GSTM1-positive after adjustment for smoking and HPV infection. Our study suggests that genetic differences in the metabolism of cigarette smoke, particularly GSTM1, may confer susceptibility to CC. Further studies using larger populations will be needed to confirm our observations and to validate data for disease prevention. 相似文献
39.
Effect of a micronutrient fortificant mixture and 2 amounts of calcium on iron and zinc absorption from a processed food supplement 总被引:3,自引:0,他引:3
Mendoza C Peerson JM Brown KH Lönnerdal B 《The American journal of clinical nutrition》2004,79(2):244-250
BACKGROUND: Iron, zinc, and calcium can interact with each other in a way that inhibits their respective absorption. On the other hand, mineral fortification has been used to improve simultaneous iron and zinc absorption from food supplements. OBJECTIVE: We evaluated the effect of a novel fortificant mixture consisting of NaFeEDTA, zinc methionine, ascorbic acid, and citric acid on iron and zinc absorption from a dry food supplement designed for preschool children. DESIGN: The standard food supplement contained cereal and legume flour, dried milk, and a mixture of micronutrients including ferrous sulfate and zinc sulfate as sources of supplemental iron and zinc, respectively. Standard and novel food products were prepared as porridge with or without the addition of 200 mg Ca as calcium phosphate. Iron absorption and zinc absorption from the food products were evaluated simultaneously in 13 nonpregnant, adult women by extrinsically labeling the products with radioisotopes of iron and zinc and carrying out whole-body counting 7 d after the food products were consumed in random order. RESULTS: The absorption of iron from the NaFeEDTA-containing (novel) food product was 1.7 times that from the ferrous sulfate-containing (standard) product (P = 0.015). There was no significant effect of dietary calcium on iron absorption. Zinc absorption was not associated with the form of zinc consumed, but higher dietary calcium was marginally associated with lower zinc absorption (P = 0.071). CONCLUSIONS: A mixture of fortificants containing NaFeEDTA, zinc sulfate or zinc methionine, ascorbic acid, and citric acid, but without calcium, can improve iron and zinc absorption from food products. A cost-benefit analysis of the novel fortificant mixture needs to be performed. 相似文献
40.
Alan J. Kaufman M.D. Raoul Concepcion Fred K. Kirchner W. Scott McDougal Alan C. Winfield 《Urologic radiology》1990,12(1):56-60
A new nonionic, low-osmolar iodinated contrast media, ioversol, was compared with another low-osmolar, nonionic contrast media, iohexol, in 80 patients undergoing intravenous urography. There were 40 patients in each contrast group. Patients were assessed for changes in vital signs, patient tolerance (heat and pain), and other adverse effects. Double-blind evaluation was also performed for comparison of the urogram image quality. There were no severe, life-threatening reactions for either contrast group. Ten patients (25%) receiving ioversol and seven (17.5%) receiving iohexol perceived body heat related to the injection of contrast material. Two patients (5%) in each group experienced mild nausea. Two patients (5%) of each group experienced noted unpleasant taste, and two patients (5%) of the iohexol group complained of headache. Vital signs remained stable without significant change in both groups, and image quality was considered equivalent. The results indicate that the two contrast agents are equivalent in image quality, safety, and incidence of adverse effects. 相似文献