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991.
Prospective study of diarrheal illnesses in northeastern Brazil: patterns of disease, nutritional impact, etiologies, and risk factors 总被引:17,自引:0,他引:17
R L Guerrant L V Kirchhoff D S Shields M K Nations J Leslie M A de Sousa J G Araujo L L Correia K T Sauer K E McClelland 《The Journal of infectious diseases》1983,148(6):986-997
Diarrhea is a leading cause of death in tropical countries. One of the highest childhood mortalities is in northeastern Brazil, where little is known about the morbidity, etiology, and risk factors of diarrhea. Prospective village surveillance over 30 months revealed diarrhea attack rates of more than seven episodes per child-year at six to 11 months of age among the children of the poorest families. Other risk factors included early weaning and the lack of toilets. Diarrhea led to weight loss and stunted growth. Enterotoxigenic Escherichia coli and rotaviruses were the most common pathogens, accounting for 21% and 19% of cases, respectively, followed by Shigella species (8.0%), Campylobacter jejuni (7.5%), Giardia species (6.7%), Strongyloides species (5.3%), and enteropathogenic E coli serotypes (4.6%). Most (84%) enterotoxigenic E coli were isolated during the rainy season of October to March (P less than 0.03), whereas 71% of rotaviral illnesses occurred during the drier months of June to October (P less than 0.03). In the present study, the early occurrence and nutritional impact of diarrhea and weaning, as well as the major etiologic agents of diarrhea and their different seasonal patterns have been defined for this region in which life-threatening diarrhea is endemic. 相似文献
992.
William H. Ryan Brian W. Hummel Robert N. McClelland 《American journal of surgery》1982,144(6):740-743
The general surgeon can be expected to encounter patients who require major hepatic resection with increasing frequency. Successful resection of large neoplasms requires meticulous attention to surgical technique. Use of the Lin hepatic compression clamp significantly reduces morbidity and mortality, operative time, and blood loss, and should be employed whenever possible during hepatectomy. In addition, an extended subcostal incision with use of the table-attached Hepco Upper Hand retractor offers superb exposure and avoids the morbidity associated with thoracoabdominal incisions. 相似文献
993.
994.
995.
Pigeon-associated strains of Salmonella enterica serovar Typhimurium phage type DT2 have genomic rearrangements at rRNA operons 下载免费PDF全文
Helm RA Porwollik S Stanley AE Maloy S McClelland M Rabsch W Eisenstark A 《Infection and immunity》2004,72(12):7338-7341
Strains from a subgroup of Salmonella enterica serovar Typhimurium frequently associated with pigeon infections were tested for genomic anomalies and virulence in mice. Some strains have a genomic inversion between rrn operons. Two prophages found in the common laboratory strain LT2 were absent. Pigeon-associated strains are still virulent in mice. 相似文献
996.
In silico dissection of cell-type-associated patterns of gene expression in prostate cancer 总被引:6,自引:0,他引:6 下载免费PDF全文
Stuart RO Wachsman W Berry CC Wang-Rodriguez J Wasserman L Klacansky I Masys D Arden K Goodison S McClelland M Wang Y Sawyers A Kalcheva I Tarin D Mercola D 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(2):615-620
Prostate tumors are complex entities composed of malignant cells mixed and interacting with nonmalignant cells. However, molecular analyses by standard gene expression profiling are limited because spatial information and nontumor cell types are lost in sample preparation. We scored 88 prostate specimens for relative content of tumor, benign hyperplastic epithelium, stroma, and dilated cystic glands. The proportions of these cell types were then linked in silico to gene expression levels determined by microarray analysis, revealing unique cell-specific profiles. Gene expression differences for malignant and nonmalignant epithelial cells (tumor versus benign hyperplastic epithelium) could be identified without being confounded by contributions from stroma that dominate many samples or sacrificing possible paracrine influences. Cell-specific expression of selected genes was validated by immunohistochemistry and quantitative PCR. The results provide patterns of gene expression for these three lineages with relevance to pathogenetic, diagnostic, and therapeutic considerations. 相似文献
997.
998.
Sonographic study of 164 patients (328 eyes) in the present series highlights the advantages of ocular ultra sonography (B-mode) in the evaluation of retinal disorders especially in patients with opaque ocular media. B-mode sonography of the eye is a rapid, cheap, safe and reliable investigation for the eye. The sensitivity and specificity of this modality in detecting ocular pathologies has been recorded as extremely high and is of great value to the eye surgeon for a preoperative assessment of the posterior segment when fundoscopy is not possible due to opaque ocular media from various causes.Key Words: Retina, Sonology 相似文献
999.
OBJECT: The authors evaluated a new non-cross-linked, propylene oxide-treated, acellular collagen matrix for use as a dural substitute in rabbits. They then compared this material to a commonly used dural substitute as well as to native dura mater used during primary closure. METHODS: Forty-six rabbits were randomly assigned to eight groups of five or six rabbits each. These groups differed according to the type of closure material that was used during surgery (native dura, control dural substitute, or experimental dural substitute) and the duration of convalescence. At the end of the experiment, the tightness of the duraplasty was assessed in each live rabbit by continuous infusion of fluid into the cistema magna until leakage was detected. The animals were killed and each specimen was sectioned and studied histologically. The authors found that the experimental dural substitute was safe in animals for this application, that it held sutures well, and that a watertight closure was usually achieved. There were fewer adhesions between the experimental material and neural tissue was less likely to adhere to the cranium than the control graft. Histological examination showed that the experimental material had slightly more spindle cells and vascularity than the control graft. CONCLUSIONS: The experimental graft material has several features that make it an attractive candidate for use as a dural substitute. 相似文献
1000.
Venous thromboembolism prophylaxis: patients at high risk to fail intermittent pneumatic compression 总被引:5,自引:0,他引:5
Clarke-Pearson DL Dodge RK Synan I McClelland RC Maxwell GL 《Obstetrics and gynecology》2003,101(1):157-163
To identify patients who fail intermittent pneumatic compression and who might be considered for other more intense thromboembolic prophylaxis.We conducted a retrospective review of consecutive gynecologic surgery patients treated with intermittent pneumatic compression. Risk factors associated with thromboemboli and demographic data were reviewed. Clinical suspicion of thromboemboli was confirmed by established diagnostic techniques such as duplex Doppler ultrasound and ventilation perfusion scanning. The association between individual risk factors and the incidence of thromboemboli was identified. To control for confounding of variables, multivariable stepwise logistic regression analysis was performed.A total of 1862 patients undergoing gynecologic surgery between 1996 and 1997 were treated perioperatively with intermittent pneumatic compression. The overall incidence of postoperative thromboemboli was 1.3% (15 cases of clinically significant postoperative pulmonary emboli and nine deep venous thrombosis). Risk factors associated with the occurrence of thromboemboli were: cancer (P =.001), history of deep venous thrombosis (P =.03), hypertension (P =.05), use of antihypertensives (P =.04), and age at least 60 years (P =.002). Intraoperative risk factors included duration of anesthesia more than 3 hours (P =.05). The multivariable regression analysis found that the diagnosis of cancer (P =.001), history of deep venous thrombosis (P =.006), and age greater than 60 years (P =.04) were independent prognostic factors. Patients with two or three of these variables had a 3.2% incidence of developing thromboemboli as compared with a 0.6% incidence of thromboemboli if the patient had none or one risk factor.Patients most likely to fail intermittent pneumatic compression prophylaxis include those with cancer, a past history of deep venous thrombosis, or who are 60 years or older. This information identifies a "higher-risk" group of patients who should be considered for more intense prophylaxis programs. 相似文献