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101.
Background Laparoscopic bypass surgery for the palliation of gastric and biliary obstruction is associated with a rapid recovery. This study aimed to extend its application to other aspects in the management of patients with periampullary cancer. Methods Between 2001 and 2004, 21 patients (median age, 68 years) underwent laparoscopic gastric (n = 8), biliary (n = 5), and combined gastric and biliary (n = 8) bypass. In addition to its therapeutic role (n = 12), indications included a concomitant prophylactic gastric (n = 3) and biliary (n = 2) bypass as well as pre- 1 Whipple’s relief of deep jaundice at the time of staging laparoscopy (n = 3). Construction of the biliary bypass to the gallbladder (n = 11) or bile duct (n = 2) was based on preoperative imaging. Results All procedures were completed laparoscopically. The median operating times for gastric, biliary, and combined bypass were 75, 60, and 130 min, respectively. The addition of a prophylactic bypass did not significantly prolong the operating time, as compared with a single therapeutic bypass. One patient died postoperatively of aspiration pneumonia. The postoperative hospital stay (median, 4 days) was not significantly influenced by the type of bypass. No recurrence of or new obstructive symptoms developed during the follow-up period after a therapeutic or prophylactic bypass. Conclusions Applications of laparoscopic gastric and biliary bypass can safely be expanded to include a prophylactic role and preresection relief of obstructive jaundice. Prophylactic bypass surgery does not prolong operating time or hospital stay significantly and prevents future onset of obstructive symptoms.  相似文献   
102.
After renal transplantation, persistent glomerular disease affecting the native kidneys typically causes albuminuria, at least for a period of time, making it difficult to determine in a noninvasive fashion whether proteinuria originates in the native kidneys or the renal allograft. To address this problem, dynamic contrast-enhanced magnetic resonance imaging (MRI) using gadolinium (Gd)-based albumin-bound blood pool contrast agent (MS325) to localize proteinuria was investigated. Glomerular proteinuria was induced in Sprague-Dawley rats by intravenous injection of puromycin aminonucleoside (PAN), whereas control rats received physiologic saline vehicle. Both groups of animals underwent a 40-min dynamic contrast-enhanced MRI using radio frequency spoiled gradient echo imaging sequence after injection of Gd-labeled MS325. Contrast uptake and clearance curves for cortex and medulla were determined from acquired MR images. Compared with controls, proteinuric rats exhibited significantly lower elimination rate constants. The use of gadopentetate dimeglumine (Gd-DTPA) as a contrast agent showed smaller and less specific differences between proteinuric and control groups. In rats with one proteinuric kidney (PAN-treated) and one normal kidney (transplanted from a normal rat), MRI using MS325 was able to differentiate between the two kidneys. The results suggest that MRI with an albumin-bound blood pool contrast agent may be a useful noninvasive way to localize proteinuria. If this technique can be successfully applied in human patients, it may allow for the localization of proteinuria after kidney transplant and thereby provide a noninvasive way to detect disease affecting the renal allograft.  相似文献   
103.
Whether nonhuman primates exhibit population-level handedness remains a topic of considerable debate. Previous research has shown that chimpanzees are right-handed when frequencies of hand use are recorded but some have questioned the validity of this approach. In this study, we evaluated handedness in 180 captive chimpanzees for a task measuring bimanual actions. Bouts rather than frequency of hand use were recorded in each subject. Population-level right-handedness was found using both continuous and nominal scales of measurement. Neither sex nor rearing history had a significant effect on hand use. These results indicate that chimpanzees are right-handed, even when using a more conservative measure of handedness. Limitations in the use of bouts in handedness assessment are also discussed.  相似文献   
104.
105.
Local field potentials (LFP) are bioelectric signals recorded from the brain that reflect neural activity in a high temporal resolution. Separating background activity from that evoked by specific somato-sensory input is a matter of great clinical relevance in neurology. The coherence function is a spectral coefficient that can be used as a detector of periodic responses in noisy environments. Auditory steady-state responses to amplitude-modulated tones generate periodic responses in neural networks that may be accessed by means of coherence between the stimulation signal and the LFP recorded from the auditory pathway. Such signal processing methodology was applied in this work to evaluate in vivo, anaesthetized Wistar rats, activation of neural networks due to single carrier sound stimulation frequencies, as well as to evaluate the effect of different modulating tones in the evoked responses. Our results show that an inappropriate choice of sound stimuli modulating frequencies can compromise coherence analysis, e.g. misleading conclusions due to mathematical artefact of signal processing. Two modulating frequency correction protocols were used: nearest integer and nearest prime number. The nearest prime number correction was successful in avoiding spectral leakage in the coherence analysis of steady-state auditory response, as predicted by Monte Carlo simulations.  相似文献   
106.
107.
Purulent pericarditis in children is a life-threatening disease that requires early diagnosis and immediate intervention. This cardiac emergency is rarely seen in the western world. However, cases of purulent pericarditis are still being reported in developing countries. We describe our experience with five cases of purulent pericarditis in children seen between 1998 and 2002. Haemophilus influenzae bacteria were isolated in all except one case. With active management, all five children survived.  相似文献   
108.
OBJECTIVE: Our purpose was to compare the effectiveness, women's views of the termination procedure, and success of umbilical cord culture for vaginal and oral misoprostol versus intra-amniotic prostaglandin PGF(2alpha) for second-trimester pregnancy termination (STPT). STUDY DESIGN: We randomized 217 women, 15 to 24 weeks' gestation, into 3 groups. Oral (OM) and vaginal (VM) misoprostol groups received 400 microg of misoprostol every 4 hours for 24 hours. The intra-amniotic PGF(2alpha) (IAPG) group received 40 mg of PGF(2alpha) followed by oxytocin infusion. Women completed self-administered questionnaires 3 weeks after the termination procedure. Umbilical cord samples were collected at delivery for karyotype analysis. The primary outcome was the time from start of the procedure to placental delivery. Secondary outcomes were maternal complications, women's acceptance of the termination procedure, and success rates of umbilical cord culture. RESULTS: The time was longer for the OM group (30.5+/-14.4 hours) compared with the VM group (18.3+/-8.2 hours) and the IAPG group (21.1+/-10.2 hours), P<.001 for both comparisons. Women in the VM group reported being more willing to repeat the termination method in the future and reported fewer side effects than those in the other groups, P<.001. Failure rates for umbilical cord cultures were 9.6%, 17.0%, and 45.6% for the VM, OM, and IAPG groups, respectively. CONCLUSION: Oral misoprostol is less effective than intra-amniotic PGF(2alpha) or vaginal misoprostol for STPT. Women report vaginal misoprostol more acceptable than other methods. Umbilical cord culture failure rate is highest in the IAPG group.  相似文献   
109.
Although thyroid hormones are indicated for hypothyroidism, their therapeutic benefit in treating other medical and psychiatric conditions has not been adequately studied. We review the use of thyroid hormones in treating psychiatric and medical conditions in the euthyroid patients. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors acknowledge discussing the off-label (which includes unlabeled or unapproved) use of T3 and T4 supplementation in the treatment of psychiatric and medical conditions in euthyroid patients.  相似文献   
110.
OBJECTIVES: To test the hypothesis that impaired hemodynamic orthostatic changes commonly observed in the elderly may be related to age-related increase in arterial wall stiffness. DESIGN: Convenience sample of consecutive patients admitted for falls. SETTING: Acute- and intermediate-care geriatric ward of a French hospital. PARTICIPANTS: Fifty-seven elderly patients (46 women) consecutively admitted to a geriatric ward with a history of recent falls. MEASUREMENTS: Orthostatic hypotension (OH) was assessed using blood pressure measurements in the supine position and 1, 2, and 3 minutes after standing. Arterial wall stiffness was assessed using upper-limb and aortic pulse-wave velocities, measured with an external pressure transducer connected to a computer. RESULTS: OH was present in 18 patients with a mean age+/-standard deviation of 85.4+/-7.6 (5 men, 13 women) and absent in 39 patients aged 83.7+/-6.2 (6 men, 33 women). Upper-limb pulse-wave velocity was significantly higher, by 16%, in patients with OH than those without (9.91 vs 8.53 m/s; P<.02). Significant correlations were found between upper-limb pulse-wave velocity and systolic blood pressure changes after 1 minute of standing (r=0.263, P<.05) and maximal diastolic blood pressure change after standing (r=0.351, P<.01). CONCLUSION: Upper-limb arterial wall stiffness was significantly greater in elderly patients with OH than in patients without OH and was significantly related to blood pressure changes after standing. These results highlight the possible role of age-related changes in the arterial tree in the hemodynamic response to orthostatic challenges.  相似文献   
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