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991.
While malformations of the upper airway are rare, they present challenging management problems and have a potentially devastating impact during anesthesia. This case report describes the management of a patient with a massive supraglottic venous malformation as he underwent transvenous embolization.  相似文献   
992.
Subcutaneous injections of monosodium L-glutamate (MSG) were administered, as a neurotoxin, at a dose of 4 mg/g body weight to rat pups on days 1 and 3 postnatally. Pinealectomy was performed at 6 weeks of age, and animals were allowed to mature. The intact MSG-treated rats showed a decrease of lordosis quotient in females and a reduction of ejaculation frequency and an increase in mount frequency in males. Pinealectomy caused no significant improvement on sexual behavior of the saline-treated normal rats, but it caused a marked improvement of the sexual receptivity in MSG-treated female rats and reinstated ejaculation in MSG-treated males. The circulatory sex steroid levels, estrogen in females and androgen in males, were not significantly different between the intact and pinealectomized MSG-treated groups in the respective sexes, whereas the progesterone level in females was significantly elevated in the pinealectomized MSG-treated group compared with the intact MSG-treated group. These findings suggest that the pineal gland plays an inhibitory role on the sexual behavior of MSG-treated rats and the improvement of sexual behavior following pinealectomy may be dependent on certain mechanisms other than the actions of circulatory androgens or estrogens.  相似文献   
993.
Several investigators have suggested that the lymphatic circulation reduces ultrafiltration in continuous ambulatory peritoneal dialysis (CAPD). The purpose of this study was to assess lymphatic drainage of the peritoneal cavity directly in anesthetized sheep under dialysis conditions. Lymph was collected from the caudal mediastinal lymph node and the thoracic duct, both of which are involved in the lymphatic drainage of the ovine peritoneal cavity, and from the prescapular lymph node, which is not involved in peritoneal lymphatic drainage. Fifty ml/kg volumes of a mildly hypertonic dialysis solution (Dianeal 1.5%) containing 25 microCi 125I-human serum albumin were instilled into the peritoneal cavity, and lymph flows and the appearance of labeled protein in the lymphatic and vascular compartments were monitored for six hours. Following the instillation of dialysis fluid there was a tendency for lymph flow rates from the thoracic duct to increase but these changes were not significant. However, flow rates from the caudal lymphatic demonstrated significant increases, especially in the final three hours of the monitoring period. Only about 8% of the radiolabeled albumin was removed from the peritoneal cavity over six hours (that is, 92% was left in the peritoneal space). Of the albumin removed, approximately 17% of this was drained by abdominal visceral lymphatics into the thoracic duct. About 25% passed through the diaphragm into the caudal mediastinal lymph node and into efferent lymph. Since the efferent lymphatic duct of the caudal mediastinal node empties directly into the thoracic duct, about 42% of all protein removed from the peritoneal cavity of the sheep was ultimately transported to the thoracic duct.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
Citalopram is a chiral antidepressant drug. Its eutomer, S-citalopram (escitalopram), has recently been introduced as an antidepressant. In an open pilot study, four outpatients and two inpatients with a major depressive episode (ICD-10), and who were nonresponders to a 4-week pretreatment with 40-60 mg/day citalopram, were comedicated for another 4-week period with carbamazepine (200-400 mg/day). Some of the patients suffered also from comorbidities: Phobic anxiety disorder with panic attacks (n=2), generalised anxiety disorder, alcohol abuse, dependent personality disorder, hypertension (n=1). After a 4-week augmentation therapy with carbamazepine, a significant (P<0.03) decrease of the plasma concentrations of S-citalopram and R-citalopram, by 27 and 31%, respectively, was observed. Apparently, the probable induction of CYP3A4 by carbamazepine results in a nonstereoselective increase in N-demethylation of citalopram. Moreover, there was a significant (P<0.03) decrease of the ratio S/R-citalopram propionic acid derivative, the formation of it being partly regulated by MAO-A and MAO-B. Already, within 1 week after addition of carbamazepine, there was a slight but significant (P<0.03) decrease of the MADRS depression scores, from 27.0+/-7.7 (mean+/-S.D.) to 23.3+/-6.6, and the final score on day 56 was 18.8+/-10.9. The treatment was generally well tolerated. There was no evidence of occurrence of a serotonin syndrome. After augmentation with carbamazepine, treatment related adverse events were: Nausea in one case, diarrhea in one case, and rash in two cases. In conclusion, the results of this pilot study suggest that carbamazepine augmentation of a citalopram treatment in previous nonresponders to citalopram may be clinically useful, but that in addition carbamazepine can lead to a decrease of the plasma concentrations of the active enantiomer escitalopram.  相似文献   
995.
996.
997.
Both vascular relaxation and cAMP accumulation mediated by beta adrenergic agonists declines with increasing age. We have developed a method to measure the biologically relevant cAMP bound to the regulatory subunits of cAMP-dependent protein kinase in rat aorta. In homogenates of rat aorta, binding of [3H]cAMP was saturable with a Kd of 8.0 +/- 1.5 nM; the dissociation of [3H]cAMP from the binding sites was comprised of fast and slow components at 4 degrees C. Endogenous cAMP binding in aortas stimulated with isoproterenol (10(-5) M) or forskolin (10(-5) M) was quantitated by radioimmunoassay. Compared to basal values, isoproterenol increased cAMP binding by 37% (P less than 0.05) in aortas from young animals (5-6 weeks) but had essentially no effect on binding in older animals (9-11 months). In contrast, forskolin, which causes full relaxation in aortas from older rats, equally elevated bound cAMP values in aortas in the two age groups. In addition, the ratio of total cAMP binding sites to cAMP-dependent protein kinase catalytic activity was 45% higher in aortas from the older rats, suggesting that there were proportionately more regulatory subunits in those vessels. The deficit in isoproterenol-stimulated cAMP binding in vascular smooth muscle in older animals may in part explain the loss in relaxation mediated by beta adrenergic agonists.  相似文献   
998.
Fenestration of the internal carotid artery (ICA) is extremely rare on clinical settings. Six cases of fenestration in intracranial and 8 in extracracranial ICA have ever been reported in literature. Authors describe two cases of fenestration at the extracranial ICA that were initially suspected of the dissection of ICA on MRA/I. Both angiography and CT angiography (CTA) disclosed the fenestration, which located at C2 vertebral levels. To confirm the fenestration at extracranial ICA is important in such an occasion that mimic the dissection of ICA, especially in patients who complain of cervical pain, mass and other related symptoms. Differences in the fenestration, the dissection and atherosclerosis on imaging, were reviewed and discussed.  相似文献   
999.
The purpose of this study was to examine the test-retest reliability for reports of sexual behavior from the National Institutes of Mental Health Multisite HIV Prevention Trial survey for two Asian samples. Thai (N = 37) and Korean (N = 46) respondents aged 19-37 years (M = 29, SD = 4.61) completed face-to-face interviews to assess their sexual risk in their ethnic language 3-7 days apart. Test-retest coefficients ranged from .65 to 1.00 demonstrating acceptable reliability of the survey among Thai and Korean adults. The discussion focuses on the development of HIV risk assessments that take into consideration ethnic diversity found within the Asian and Pacific Islander community.  相似文献   
1000.
Femoral neuropathy can result from diverse etiologies following abdominal surgery. We describe four cases of postoperative femoral neuropathy after proctological procedures that were carried out at our hospital. The related symptoms developed occultly but eventually impaired patient motor or sensory functions in the lower extremities. When the patient fails to address associated suffering, it is easy for clinicians to neglect this type of morbidity. All patients recovered from neuropathy following timely detection of the disease entity confirmed by electromyography and nerve conduction studies, followed by adequate rehabilitation management. We hypothesize that postoperative femoral neuropathy may be closely related to unsuitable applications of self-retaining retractors, rather than being associated with other factors, such as gender, age, surgery time or body mass index (BMI). Furthermore, we used a literature review to examine the pathophysiology, diagnoses and treatment modalities of femoral neuropathy resulting from inappropriate placement of self-retaining retractors. Based on a thorough comprehension of the femoral nerves anatomical course and meticulous placement of retractor blades, these types of iatrogenic complications may be prevented.  相似文献   
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