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11.
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Ureteral hernia is uncommon and usually misdiagnosed. From an anatomic point of view, we can distinguish between two uretero-inguinal
hernias: intraperitoneal and extraperitoneal. Ureter inguinal hernias are nearly always indirect. This kind of hernia can
include the ureter alone or, frequently, other abdominal sliding organs within the hernia sac (bladder, bowel tracts, etc.).
Kidneys and urinary tracts present normal anatomic conformation, although renal ptosis may be found. As of July 2004, 139
cases of ureteral hernia had been described in the literature. Here we report a case of inguino-scrotal herniation of double
district ureter and review the current literature to analyze the main clinical characteristics of this pathology and to establish
pitfalls. 相似文献
13.
左双腔支气管导管管端位置与吸气峰压变化的关系 总被引:13,自引:3,他引:10
目的 观测无隆突钩双腔支气管导管(DLT)管端位置与吸气峰压(Ppeak)以及肺顺应性环形状改变的关系,探讨用Ppeak和顺应性环的变化评估DLT管端位置的可行性。方法 拟行右侧剖胸手术的成年患者32例,静脉诱导后插入左Mallinckrodt DLT,吸入氧化亚氮和地氟醚维持麻醉。按纤维支气管镜(FOB)确认DLT管端位置和通气方式将观测过程分为四个阶段:第一阶段(S1),管端位置正确的双肺通气;第二阶段(S2),管端位置正确的左侧单肺通气;第三阶段(S3),管端插入左下支气管(置管过深)的左侧单肺通气;第四阶段(S。),管端处在左支气管开口(置管偏浅)的左侧单肺通气。每阶段均机械通气15min。结果 回归方程预计插管深度与FOB检查符合者占71.9%。S2时Ppeak值比S1时增加50.8%,肺顺应性(Cdyn)值减少36.2%;S3时Ppeak值比S1时增加87.4%,Cdyn值减少56.8%。PV环曲线斜率向右明显移位,环体显著延长。结论 用无隆突钩DLT行肺隔离,在无FOB定位的条件时,联合应用听诊法、回归方程预计插管深度、动态监测气道峰压和P-V环的变化综合评估,可提高DLT管端的正确到位率。单肺通气的气道峰压超过双肺通气时的1.65倍,且气道峰压超过25cm H2O.应高度怀疑DLT管端发生过深移位。 相似文献
14.
Normal cerebral perfusion measurements using arterial spin labeling: reproducibility, stability, and age and gender effects. 总被引:4,自引:0,他引:4
Laura M Parkes Waqar Rashid Declan T Chard Paul S Tofts 《Magnetic resonance in medicine》2004,51(4):736-743
Before meaningful conclusions can be drawn from clinical measures of cerebral blood perfusion, the precision of the measurement must be determined and set in the context of inter- and intrasubject sources of variability. This work establishes the reproducibility of perfusion measurements using the noninvasive MRI technique of continuous arterial spin labeling (CASL). Perfusion was measured in 34 healthy normal subjects. Intersubject variability was assessed, and age and gender contributions were estimated. Intersubject variation was found to be large, with up to 100% perfusion difference for subjects of the same age and gender. Repeated measurements in one subject showed that perfusion remains remarkably stable in the short term when compared with intersubject variation and the large capacity for perfusion change in the brain. A significant decrease in the ratio of gray-matter to white-matter perfusion was found with increasing age (0.79% per year (P < 0.0005)). This appears to be due mainly to a reduction in gray-matter perfusion, which was found to decrease by 0.45% per year (P = 0.04). Regional analysis suggested that the gray-matter age-related changes were predominantly localized in the frontal cortex. Whole-brain perfusion was 13% higher (P = 0.02) in females compared to males. 相似文献
15.
High-resolution myocardial perfusion mapping in small animals in vivo by spin-labeling gradient-echo imaging. 总被引:1,自引:0,他引:1
Frank Kober Isabelle Iltis Marguerite Izquierdo Martine Desrois Danielle Ibarrola Patrick J Cozzone Monique Bernard 《Magnetic resonance in medicine》2004,51(1):62-67
An ECG and respiration-gated spin-labeling gradient-echo imaging technique is proposed for the quantitative and completely noninvasive measurement and mapping of myocardial perfusion in small animals in vivo. In contrast to snapshot FLASH imaging, the spatial resolution of the perfusion maps is not limited by the heart rate. A significant improvement in image quality is achieved by synchronizing the inversion pulse to the respiration movements of the animals, thereby allowing for spontaneous respiration. High-resolution myocardial perfusion maps (in-plane resolution=234 x 468 microm2) demonstrating the quality of the perfusion measurement were obtained at 4.7 T in a group of seven freely breathing Wistar-Kyoto rats under isoflurane anesthesia. The mean perfusion value (group average +/- SD) was 5.5 +/- 0.7 ml g(-1)min(-1). In four animals, myocardial perfusion was mapped and measured under cardiac dobutamine stress. Perfusion increased to 11.1 +/- 1.9 ml g(-1)min(-1). The proposed method is particularly useful for the study of small rodents at high fields. 相似文献
16.
Luis Hernandez-Garcia Gregory R Lee Alberto L Vazquez Chun-Yu Yip Douglas C Noll 《Magnetic resonance in medicine》2005,54(4):955-964
A new approach to modeling the signal observed in arterial spin labeling (ASL) experiments during changing perfusion conditions is presented in this article. The new model uses numerical methods to extend first-order kinetic principles to include the changes in arrival time of the arterial tag that occur during neuronal activation. Estimation of the perfusion function from the ASL signal using this model is also demonstrated. The estimation algorithm uses a roughness penalty as well as prior information. The approach is demonstrated in numerical simulations and human experiments. The approach presented here is particularly suitable for fast ASL acquisition schemes, such as turbo continuous ASL (Turbo-CASL), which allows subtraction pairs to be acquired in less than 3 s but is sensitive to arrival time changes. This modeling approach can also be extended to other acquisition schemes. 相似文献
17.
Peter Jecker Lisa A. Orloff Miriam Wohlfeil Wolf J. Mann 《European archives of oto-rhino-laryngology》2006,263(7):664-667
Chronic polypoid rhinosinusitis (CRS) is a common disease, affecting approximately 16% of the adult population in the US every year. In addition to many well known predisposing factors, an association with reflux disease is hypothesized. Such an association might explain the recurrence of polyposis in the face of improved surgical techniques and postsurgical treatment of CRS. At present it is unclear whether extraesophageal reflux directly injures the sinus mucosa, whether gastroesophageal reflux leads to vagus-mediated neuroinflammatory changes, or whether both mechanisms occur separately or simultaneously. In patients suffering from recurrent CRS (n=20) and healthy volunteers (n=20), ambulatory 24 h two channel pH testing was performed. The number of reflux events, the fraction of the total time during which pH was below 4, and the reflux area index (RAI) were determined in the esophagus as well as in the hypopharynx. Patients with recurrent CRS had significantly more reflux events in the esophagus and the fraction of pH<4 and the RAI were increased up to 10-fold compared to healthy volunteers. In contrast to the esophagus, these differences were not observed in the hypopharynx. Recurrent CRS is often associated with GERD but not with EER. Recurrent disease or prolonged recovery after surgery should raise the suspicion of reflux disease as a possible triggering factor. Because GERD itself cannot be diagnosed by laryngoscopy, and because of the subjectivity of symptoms such as heartburn, the otolaryngologist should consider double-probe pH testing as the diagnostic procedure of choice. 相似文献
18.
Allison A. Yates 《Nutrition Research And Practice》2007,1(2):89-93
Many countries such as The Republic of Korea have established their own nutritional standards, collectively termed Nutrient Reference Values(NRVs), and they vary due to the science which was reviewed, the purposes for which they are developed, and issues related to nutrition and food policy in the country. The current effort by the Codex Alimentarius Committee on Nutrition and Foods for Special Dietary Uses (CNFSDU) to update the NRVs that were established following the Helsinki Consultation in 1988 represents an opportunity to develop a set of reference values reflecting current scientific information to be used or adapted by many countries. This paper will focus on possible approaches to selecting or developing reference values which would serve the intended purpose for nutrition labeling to the greatest extent possible. Within the United States, the Food and Drug Administration (U.S. FDA) is currently reviewing regulations on nutrition labeling to better address current health issues, and is expected to enter into a process in the next few months to begin to explore how best to update nutrient Daily Values (DVs), most of which are still based on the Recommended Dietary Allowances (RDAs) of the Food and Nutrition Board, U.S. National Academy of Sciences, last reviewed and revised in 1968. In this presentation, I review the current purposes in the U.S. for nutrition labeling as identified in the 1938 Food, Drug, and Cosmetic Act as amended, the scientific basis for current nutrition labeling regulations in the United States, and the recommendations made by the recent Committee on Use of Dietary Reference Intakes in Nutrition Labeling of the Institute of Medicine (2003) regarding how to use the DRIs in developing new DVs to be used on the label in the United States and Canada. Based on these reviews, I then provide examples of the issues that arise in comparing one approach to another. Much of the discussion focuses on the appropriate role of nutrient labeling within the Nutrition Facts panel, one of the three major public nutrition education tools in the United States (along with MyPyramid and Dietary Guidelines for Americans). 相似文献
19.
20.
Use of a double balloon enteroscope facilitates caecal intubation after incomplete colonoscopy with a standard colonoscope 总被引:2,自引:0,他引:2
BACKGROUND: Caecal intubation is a necessary step in the complete endoscopic evaluation of the colon. Studies have estimated that experienced colonoscopists may fail to reach the caecum in up to 10% of cases. AIMS: To evaluate the utility of the double balloon enteroscope used for complete examination of the colon in patients with incomplete standard colonoscopy. PATIENTS: Twenty consecutive patients with incomplete colonoscopies within the Veterans Affairs Palo Alto Health Care System. Mean age of 66 years (S.D.+/-12 years, range 46-84), 16 men. METHODS: Prospective single-centre case series on the caecal intubation rate using standard double balloon enteroscope technique in patients with previous incomplete conventional colonoscopy. RESULTS: Use of the standard double balloon enteroscope technique permitted complete colonoscopy to be achieved in 95% of the patients (19/20). Seven patients (35%) had significant pathology beyond the extent of the prior incomplete colonoscopy. We performed endoscopic mucosal resection, polypectomy or biopsy. The mean time to reach the caecum was 28 min (S.D.+/-20 min, range 6-90 min). The sedation was similar to conventional colonoscopy. No complications occurred. CONCLUSIONS: The double balloon enteroscope technology and technique can be used to complete examination of the colon in patients who were referred because of incomplete standard colonoscopy. 相似文献