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991.
Fan CM Rafferty EA Geller SC Kaufman JA Brewster DC Cambria RP Waltman AC 《Radiology》2001,218(1):176-182
PURPOSE: To determine the association of patent sac branch vessels (lumbar and inferior mesenteric arteries [IMAs]) with early endoleak rate after stent-graft repair of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: Pre- and postoperative computed tomographic (CT) angiograms in 158 patients who underwent stent-graft AAA repair were retrospectively reviewed to determine the preoperative patency of IMAs and other sac branch vessels (feeders) and presence or absence of immediate postoperative endoleak. Relationships of early endoleak rate with total branch vessel, IMA, and lumbar artery patency and graft type were evaluated. RESULTS: There was a significant association between patency of sac feeders and rate of early endoleak, especially type 2. As total patent feeders increased from zero to three to four to six, total endoleak rate increased from 6% (one of 17) to 35% (30 of 86); type 2 endoleak rate, from 0% to 25%. IMA patency was significantly associated with total early endoleak rate. Increasing lumbar artery patency also was associated with significantly higher total and type 2 endoleak rates: With zero to three lumbar arteries, the total endoleak rate was 17% and type 2 endoleak rate was 13%, as compared with 60% and 50%, respectively, with more than six patent lumbar arteries. CONCLUSION: Sac branch vessel patency is associated with significantly higher early total and type 2 endoleak rates after stent-graft repair of AAAs; thus, patent sac branches play an important role in the pathogenesis of endoleaks. 相似文献
992.
Duvvuri U Charagundla SR Kudchodkar SB Kaufman JH Kneeland JB Rizi R Leigh JS Reddy R 《Radiology》2001,220(3):822-826
A fast spin-echo sequence weighted with a time constant that defines the magnetic relaxation of spins under the influence of a radio-frequency field (T1(rho)) was used in six subjects to measure magnetic resonance (MR) relaxation times in the knee joint with a 1.5-T MR imager. A quantitative comparison of T2- and T1(rho)-weighted MR images was also performed. Substantial T1(rho) dispersion was demonstrated in human articular cartilage, but muscle did not demonstrate much dispersion. T1(rho)-weighted images depicted a chondral lesion with 25% better signal-difference-to-noise ratios than comparable T2-weighted images. This technique may depict cartilage and muscular abnormalities. 相似文献
993.
Jon Kaufman Melvin C Almodovar Jeannie Zuk Robert H Friesen 《Pediatric critical care medicine》2008,9(1):62-68
OBJECTIVE: Splanchnic oximetry, as measured by near-infrared spectroscopy (NIRS), correlates with gastric tonometry as a means of assessing regional (splanchnic) oxygenation and perfusion. DESIGN: Prospective, data-gathering study. SETTING: Pediatric cardiac intensive care unit in a tertiary care children's hospital. SUBJECTS: Neonates and infants with congenital heart disease who underwent catheter intervention or surgical repair requiring cardiopulmonary bypass. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Twenty neonates and infants were studied within 48 hrs of surgery. We measured somatic saturation (rSO2) via NIRS sensors placed over the anterior abdomen (splanchnic bed) and dorsal lateral flank (renal bed). Somatic rSO2 readings were paired with simultaneous points of intramucosal gastric pH (pHi), measured by tonometry. The rSO2 readings were paired with serum lactate and measurements of systemic mixed venous saturation (SVO2). There was strong correlation between the abdominal rSO2 and pHi (r = .79; p < .0001) as well as between abdominal rSO2 and SVO2 (r = .89; p < .0001). There was also significant negative correlation between the abdominal rSO2 and serum lactate (r = .77; p < .0001). Correlations between the dorsal lateral (renal) rSO2 measurements and serum lactate and SVO2 were also significant but not as strong. CONCLUSIONS: Abdominal site rSO2, measured in infants with either single or biventricular physiology, exhibits a strong correlation with gastric pHi as well as with serum lactate and SVO2. The results indicate that rSO2 measurements over the anterior abdominal wall correlate more strongly than flank rSO2 with regard to systemic indices of oxygenation and perfusion. This study suggests that the NIRS monitor is a valid modality to obtain an easy, immediate, and noninvasive measurement of splanchnic rSO2 in infants following cardiac surgery for congenital heart disease. 相似文献
994.
Herbert E Kaufman Emily D Varnell Bryan M Gebhardt Hilary W Thompson Ephraim Atwal Helga Rübsamen-Waigmann Gerald Kleymann 《Journal of ocular pharmacology and therapeutics》2008,24(1):34-42
PURPOSE: The aim of this study was to evaluate the effect of BAY 57-1293, a helicase-primase inhibitor, on herpes simplex virus type 1 (HSV-1) reactivation in mice and its efficacy on established disease in rabbits. METHODS: BALB/c mice latent for McKrae-strain HSV-1 were reactivated via heat stress, treated with BAY 57-1293, and their corneas were swabbed for virus or the trigeminal ganglia (TG) obtained for quantification of viral DNA. New Zealand white rabbits were infected and treated topically or orally in comparison with trifluridine or valacyclovir. RESULTS: Oral BAY 57-1293 suppressed reactivation in HSV-1-infected mice and reduced the viral load in TG up to four orders of magnitude. In the rabbits, the therapeutic efficacies of topical BAY 57-1293 and trifluridine were similar. Once-daily oral BAY 57-1293 was significantly more effective than valacyclovir and as effective as twice a day topical trifluridine. CONCLUSIONS: BAY 57-1293 may be more effective than valacyclovir, without the cytotoxicity or potential healing retardation seen with trifluridine. Oral BAY 57-1293 may be a substitute for eye drops as an effective treatment for herpetic keratitis and might be useful in treating stromal keratitis and iritis, as well as preventing recurrences of ocular herpes. 相似文献
995.
Hypertension in a black population: prevalence and biosocial determinants of high blood pressure in a group of urban Nigerians 总被引:1,自引:0,他引:1
AIMS: To define the prevalence of hypertension, a major cause of morbidity and mortality in blacks, and related biosocial factors in an urban African population group. METHODS: The setting was that of a civil service population in Ibadan, a major city in Southwestern Nigeria. Nine hundred and ninety-eight civil servants selected by multistage sampling participated in the survey. Biosocial data including smoking history, alcohol use and level of physical activity; anthropometry, blood pressure and plasma glucose measurements were obtained. Diagnosis of hypertension was based on blood pressure of > or =160/95 mm Hg or known hypertensive on treatment. RESULTS: The overall prevalence rate of hypertension was 10.3% (CI, 8.4%, 12.2%), rates of 13.9% and 5.3% were obtained in men and women respectively in spite of a much higher rate of generalised obesity in the latter. Hypertension was associated with higher salary grade level, but there was no relationship found with regular exercise, smoking and alcohol. Obesity (body mass index (BMI) > or =30 kg/m2) was associated with hypertension only in women. A two-sided t-test demonstrated age, waist circumference, waist to hip ratio (WHR) and plasma glucose level as significant variables. In multivariate ANOVA models of systolic blood pressures, age, male sex and BMI were highly significant factors (P < 0.0001) and plasma glucose was also significant (P < 0.016); the same variables (except plasma glucose) were associated with diastolic blood pressures. In logistic regression models the variables which predicted hypertension were WHR, plasma glucose, age, sex and family history of diabetes. CONCLUSIONS: Prevalence of hypertension in the study was comparable to recently reported rates in urban Nigeria and similar populations in Africa. The biosocial determinants of hypertension in the urban black population were age, male gender, higher socio-economic status, BMI, plasma glucose, generalised and central adiposity. Regional fat distribution was a stronger predictor of hypertension than generalised obesity in the population. 相似文献
996.
目的采用心肌内注射方法将骨髓间充质干细胞(BMSCs)植入到正常或慢性梗死心肌中后, 研究短期内植入细胞的分布和可利用度。方法采用选择性冠状动脉结扎方法建立大鼠慢性心肌梗死模型( n =9) 。1个月后, 采用心肌内注射方法将 111 铟 - 羟基喹啉 ( 111Indium- oxine, 111In) 同位素标记的自体 BMSCs (2×106/50μL)植入到慢性梗死心肌和正常对照心肌中( n =6) 。采用序列平面针孔闪烁扫描方法测定 BMSCs移植后 2 h、1 d、3 d、7 d 时的心肌 111In 的放射活性, 并计算植入细胞在心肌内的驻留率。于细胞移植术后第 7 天切取制备心脏横断面冷冻切片, 进行组织放射微成像(Micro- imaging)和组织病理学分析, 观察植入细胞在心肌内的分布情况。结果慢性心肌梗死(MI)组的心肌 111In 的放射活性在所有测定的时间点均显著高于正常对照组(P<0.01)。心肌放射强度实测值在经由各相应时间点 BMSCs细胞 111In 的自发泄漏率的体外标定值校正后, 计算得出植入的 BMSCs 细胞在慢性梗死心肌(MI 组)中的驻留率平均为 60%, 而在正常对照组心肌中细胞的驻留率只有 25%(P <0.01), 并在 7 d 的随访期中保持稳定。组织放射微成像和组织病理学分析都证实植入的 BMSCs 主要分布于由注射针头插入损伤或慢性心肌梗死所造成的纤维瘢痕组织中。结论心肌内细胞移植术后 7 d 内,被植入到慢性梗死心肌中的 BMSCs 细胞的可利用度高于被植入在正常心肌中的 BMSCs 细胞的可利用度。植入心肌内的 BMSCs 主要分布于由注射针头插入损伤和慢性心肌梗死导致的纤维瘢痕组织中。 相似文献
997.
Breast cancer incidence and hormone replacement therapy: results from the MISSION study, prospective phase. 总被引:2,自引:0,他引:2
Marc Espié Jean-Pierre Daures Thierry Chevallier Pierre Mares Marie-Christine Micheletti Pia De Reilhac 《Gynecological endocrinology》2007,23(7):391-397
BACKGROUND: The MISSION Study (Menopause: Risk of Breast Cancer, Morbidity and Prevalence) is a historical-prospective study with random patient selection to determine breast cancer incidence in postmenopausal women with or without hormone replacement therapy (HRT). The first prospective follow-up phase started on 5 January 2004 and the cut-off date for data collection was 30 June 2006. PARTICIPANTS: Patients were divided into two groups: an 'exposed group' of women on HRT regimens commonly prescribed in France or who had stopped < or =5 years previously; and an 'unexposed group' of women who had never received HRT or stopped >5 years previously. In total 6755 patients were included; and prospective data were available for 4949 patients: 2693 in the exposed group and 2256 in the unexposed group. Women in the exposed group were younger, less overweight, and had fewer first-degree family histories of breast cancer than women of the unexposed group. Mean duration of HRT exposure was 8.3 years, with 31% being exposed for > or =10 years. RESULTS: The incidence of new breast cancer cases was 0.64% in the exposed group and 0.70% in the unexposed group (relative risk RR(exposed/unexposed) = 0.914, 95% confidence interval = 0.449-1.858; not modified when adjusted for age). Mean age at breast cancer diagnosis was similar in both groups. Breast cancer incidence in the exposed group was not significantly affected by the route of estradiol administration (cutaneous 0.69%; oral 0.52%) or HRT type (estradiol alone 0.28%; estradiol + progesterone 0.40%; estradiol + synthetic progestin 0.94%). CONCLUSION: No evidence was found for an increased risk of breast cancer in women exposed to HRT compared with non-exposed women. 相似文献
998.
Mélanie Sanjuan Florence Sabatier Lucille Andrac-Meyer Jean-Pierre Lavieille Jacques Magnan 《Otology & neurotology》2007,28(4):504-509
HYPOTHESIS: Autologous epidermal sheets obtained by cultivating keratinocytes of the external auditory meatus can be used to repair cutaneous defects of the ear canal. The Rheinwald and Green method has been used to know whether the produced epidermal layer preserves its specificities after the culture. BACKGROUND: Using a split-thickness skin graft during a functional ear atresia surgery does not allow for the restitution of external auditory canal self-cleaning. Some authors cultivated external auditory meatus keratinocytes and showed migration capacities of these colonies. METHODS: Samples of preauricular skin and of the bony part of the external auditory canal were harvested from 10 patients. Keratinocytes were extracted and cultured until an epidermal sheet was obtained. The output, the keratinocyte plating efficiency, and the production delay were measured during the culture. Culture product sections and biopsy sections were examined using optical microscopy after standard coloration and indirect immunohistochemistry. RESULTS: Nine epidermal layers from 10 biopsies were obtained in each group. A significant difference between external auditory meatus and preauricular keratinocyte plating efficiency was highlighted. The average production delay of 23 cm2 external auditory canal and preauricular epidermal layers was 21 days. There was no difference in the cytokeratine expression between external auditory canal and preauricular skin, nor between external auditory canal and preauricular culture products. All cultures expressed the cytokeratine 5 characteristic of stratifying epithelium. CONCLUSION: The Rheinwald and Green keratinocyte culture method allows the production of ear canal-stratified epidermal sheets, which can be used for external ear reconstruction. 相似文献
999.
Cytomegaloviral enterocolitis 总被引:6,自引:1,他引:5
Kaufman HS Kahn AC Iacobuzio-Donahue C Talamini MA Lillemoe KD Hamilton SR 《Diseases of the colon and rectum》1999,42(1):24-30
PURPOSE: Cytomegaloviral enterocolitis is an uncommon disorder that can complicate inflammatory bowel disease. It is more common in patients with acquired immunodeficiency syndrome and can occur in patients on immunosuppressive therapy for autoimmune or inflammatory diseases and in allograft recipients. Mortality rates of up to 71 percent have been reported for cytomegaloviral enterocolitis. The aims of this study were 1) to identify the presentation, underlying medical conditions, treatment, and outcome of patients with cytomegaloviral enterocolitis and 2) to determine the prevalence of this infection in patients undergoing intestinal resection for inflammatory bowel disease. METHODS: A retrospective chart review of patients with pathologic evidence of cytomegaloviral enterocolitis from 1985 through 1996 was performed. To determine the prevalence of this condition, the hospital discharge database was searched for the diagnoses of ulcerative colitis and Crohn's disease in patients who underwent bowel resection. RESULTS: 93 patients (mean age, 44 years; 66 percent males) had cytomegaloviral infection in the small intestine (n = 6), large intestine (n = 86), or appendix (n = 1). Patients with acquired immunodeficiency syndrome (n = 42), with ulcerative colitis (n = 11), with Crohn's disease (n = 11), receiving organ transplant (n = 12), receiving bone marrow transplant (n = 8), and in other immunosuppressed states (n = 11) comprised this study. Seventeen patients (18 percent) underwent intestinal resection, and the remaining 76 patients were treated medically. Abdominal pain (77 vs. 37 percent; P < 0.01) and gastrointestinal bleeding (65 vs. 34 percent; P < 0.05) were more common presenting symptoms in patients who required resection than patients in the medically managed group. Mortality was 17.6 percent in the surgically managed group and 14.5 percent in the patients who were managed medically. The median duration of ulcerative colitis in patients with coexisting cytomegaloviral infection was 12 months. The prevalence of cytomegaloviral enterocolitis was 4.6 percent in patients with ulcerative colitis and 0.8 percent in patients with Crohn's disease. CONCLUSIONS: These data suggest that cytomegaloviral infection more frequently complicates ulcerative colitis than Crohn's disease. Furthermore, a short and fulminant course of ulcerative colitis may indicate coexisting cytomegaloviral infection. The overall low mortality in this retrospective study suggests that aggressive medical and surgical treatment improves survival in patients with cytomegaloviral enterocolitis. 相似文献
1000.
Finasteride, a Type 2 5alpha-reductase inhibitor, in the treatment of men with androgenetic alopecia
In men who are genetically predisposed to develop androgenetic alopecia (AGA; male pattern hair loss), endogenous androgens alter scalp hair follicles, resulting in production of vellus-like, miniaturised hair, rather than cosmetically significant terminal hair. This change leads to a progressive decline in visible scalp hair density, readily perceived by the patient as thinning and, eventually, baldness. Dihydrotestosterone (DHT), a metabolite of testosterone produced by the enzyme 5alpha-reductase, has been implicated as the specific androgen in the pathogenesis of AGA. Men genetically deficient in the Type 2 isoenzyme of 5alpha-reductase do not develop AGA. Moreover, Type 2 5alpha-reductase has been detected in scalp hair follicles, and balding scalps contain increased Type 2 5alpha-reductase activity and DHT levels. Taken together, these findings provide a rationale for the use of Type 2 5alpha-reductase inhibitors in the treatment of men with AGA. Finasteride, a specific and potent inhibitor of human Type 2 5alpha-reductase, decreases the formation of DHT from testosterone. Originally developed for the treatment of men with benign prostatic hyperplasia (BPH) as a 5 mg tablet, finasteride was subsequently evaluated as a treatment for AGA. Clinical studies in balding men demonstrated that finasteride reduced scalp DHT levels and improved hair growth, confirming the role of DHT in the pathophysiology of AGA. Dose-ranging studies established the optimal dose of 1 mg/day for the treatment of men with this disorder. Large, multicentre studies established the safety and efficacy of finasteride 1 mg, leading to marketing of Propecia (finasteride 1 mg) as a new treatment for men with AGA. 相似文献