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101.
Nitrous oxide anesthesia has been implicated as contributing to the development of delayed tension pneumocephalus following surgery performed in the sitting position. The authors tested the hypothesis that withdrawal of nitrous oxide anesthesia administered during formation of an intracranial gas cavity would lead to a decrease in intracranial pressure (ICP) as N2O diffuses from the cavity back into the blood. Ten halothane-anesthetized rabbits were prepared for measurement of supracortical ICP and arterial blood pressure (BP) and for intracranial volume alterations via a cisterna magna infusion catheter. Hyperventilation (Paco2 = 28-30 mmHg) and mannitol were used to shrink the brain to accommodate intracranial infusion of either air or lactated Ringer's (LR) solution, which was used to elevate ICP to between 10-15 mmHg from a baseline ICP of 2.1 +/- 2.5 mmHg over a period of 8 to 10 min. Following stabilization at an elevated ICP, inhalation of nitrous oxide (75%) was either initiated or withdrawn (if already present during the induced ICP increase) and the subsequent changes in mean ICP and BP were recorded. Following ICP elevation with LR to 10 +/- 1 mmHg, initiation of 75% N2O administration resulted in no change in ICP and modest increases (P less than 0.05) in BP and cerebral perfusion pressure (CPP = BP - ICP) after 4 min. However, when ICP was raised (to 12 +/- 3.5 mmHg) with intracranial air infusion, subsequent initiation of 75% N2O inhalation caused an abrupt ICP increase to 22.3 +/- 9 mmHg (from control P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
102.
103.
A membrane-coated fiber (MCF) array approach was developed for quantitative assessment of skin absorption from chemical mixtures, which was based on the similarity in the absorption mechanisms of the MCF membrane and the stratum corneum of the skin. A set of probe compounds were used to detect the relative molecular interaction strengths of chemicals with the vehicle and the membranes, which provided a linkage between the skin permeability (log k) and MCF partition coefficients (log KF). A predictive model was established via multiple linear regression analysis of the data matrix of experimentally measured log k value and log KFm values; log k=a0+a1 log KF1+a2 log KF2+...+an log KFm, where m is the number of diverse MCFs. Twenty-five probe compounds and three MCFs (polydimethylsiloxane for lipophilic, polyacrylate for polarizable, and CarboWax for polar interactions) were used to demonstrate the model development processes in the MCF array approach. The skin permeability of the probe compounds was measured with conventional diffusion cell experiments using dermatomed porcine skin. Three predictive models were established for skin permeability prediction from chemical mixtures in water, 50% ethanol, and 1% sodium lauryl sulfate (SLS) with R2 values of 93, 91, and 83, respectively. The log k and log KF values were considerably altered by the addition of ethanol or SLS into the dose vehicle; however, their correlations to skin permeability remained strong under various conditions. These results suggested that the experimentally based MCF array approach can be used to predict skin absorption from chemical mixtures in different vehicles or formulations. 相似文献
104.
Eduardo Domínguez-Adame Lanuza Encarnación Jiménez Andrade Antonio Rodríguez Fernández Jaime Medina Díez 《Clinical & translational oncology》2005,7(2):78-80
Primary linitis plastica of the rectum is an infrequent and unusual rectal carcinoma. We report a new case that presented clinically as a haemorrhoidal syndrome. We comment on the characteristics--clinical picture and histopathology--of this uncommon presentation of rectal tumour, as well as its clinical history and prognosis taking into account that the literature consulted indicated the unusualness of primary linitis plastica of the rectum. 相似文献
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106.
OBJECTIVE: The purpose of this study was to examine the predictive relationship of categorization and deductive reasoning abilities to performance of instrumental activities of daily living (IADL) among adults with brain injury. METHOD: A correlational research design was used to examine the performance of 19 patients from a neurosurgery acute care unit on Toglia's Category Assessment (TCA), the Deductive Reasoning test (DR), and the Observed Tasks of Daily Living-Revised. RESULTS: Multiple regression analysis indicated that categorization and deductive reasoning accounted for a significant proportion of the variance in IADL performance scores, with deductive reasoning making the greater contribution. Demographic characteristics such as age and education reduced the power of the previous variables, especially of the categorization. CONCLUSION: The results of this study indicate that assessments of categorization and deductive reasoning abilities of persons with brain injury may be good predictors of IADL functional performance. Results support the use of the TCA and DR as quick measures of a person's cognitive and functional abilities. Furthermore, this study provides preliminary results to support that categorization and deductive reasoning abilities are fundamental for the performance of IADL skills. 相似文献
107.
108.
Combined open and laparoscopic approach to chronic pain following open inguinal hernia repair 总被引:1,自引:0,他引:1
Introduction: Chronic groin pain is the most common long-term complication after open inguinal hernia repair. Traditional surgical management
of the associated neuralgia consists of injection therapy followed by groin exploration, mesh removal, and nerve transection.
The resultant hernia defect may be difficult to repair from an anterior approach. We evaluate the outcomes of a combined laparoscopic
and open approach for the treatment of chronic groin pain following open inguinal herniorrhaphy. Methods: All patients who underwent groin exploration for chronic neuralgia after a prior open inguinal hernia repair were prospectively
analyzed. Patient demographics, type of prior hernia repair, and prior nonoperative therapies were recorded. The operation
consisted of a standard three trocar laparoscopic transabdominal preperitoneal hernia repair, followed by groin exploration,
mesh removal, and nerve transection. Outcome measures included recurrent groin pain, numbness, hernia recurrence, and complications.
Results: Twelve patients (11 male and 1 female) with a mean age of 41 years (range 29–51) underwent combined laparoscopic and open
treatment for chronic groin pain. Ten patients complained of unilateral neuralgia, one patient had bilateral complaints, and
one patient complained of orchalgia. All patients failed at least two attempted percutaneous nerve blocks. Prior repairs included
Lichtenstein (n=9), McVay (n=1), plug and patch (n=1), and Shouldice (n=1). There were no intraoperative complications or wound infections. With a minimum of 6 weeks follow up, all patients were
significantly improved. One patient complained of intermittent minor discomfort that required no further therapy. Two patients
had persistent numbness in the ilioinguinal nerve distribution but remained satisfied with the procedure. Conclusions: A combined laparoscopic and open approach for postherniorrhaphy groin pain results in good to excellent patient satisfaction
with no perioperative morbidity. It may be the preferred technique for the definitive management of chronic neuralgia after
prior open hernia repair. 相似文献
109.
Jim A Reekers 《Journal of endovascular therapy》2006,13(5):697; author reply 698-697; author reply 699
110.