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101.
Jordi Sabadell Jose Luis Sanchez-Iglesias Raquel Ferrer Teresa Higueras Jaume Alijotas Luis Cabero 《The journal of maternal-fetal & neonatal medicine》2007,20(5):423-425
Maternal group B streptococcal infection is an uncommon entity. Herein we describe a case of a 27-year-old-woman who presented life-threateniing group B streptococcus meningitis with an ectopic cervical pregnancy. No other infectious focus have been found. To our knowledge this is the first time that this association has been reported. 相似文献
102.
103.
Although tricyclic antidepressant are especially useful in the treatment of chronic pain conditions, most of the work about its mechanism of action has been made on acute pain tests. The present study was aimed at studying the role played by noradrenergic and opioidergic influences on the antinociceptive activity of subchronically administered clomipramine in the formalin test (a tonic pain model) in rats. Clomipramine produced antinociception after 7 days, administration (2.5 mg/kg/day), an effect equivalent to that obtained by acute morphine (5 mg/kg). The antinociceptive effect of clomipramine was inhibited by the following: nonspecific blocking of alpha1-and alpha2-adrenoceptors by phentolamine, specific blocking of alpha1-adrenoceptors by prazosin; stimulation of alpha2 receptors by clonidine; and blocking of the opioid receptors by naloxone. Blocking the alpha2-receptors with yohimbine did not antagonize the effect of clomipramine. These results suggest that clomipramine produces antinociception in this test, partly via the participation of the endogenous opioid system and partly by further activating or potentiating previously activated noradrenergic pathways which are involved in the control of pain information. 相似文献
104.
105.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Luis A. Rivas M.D. Steven Falcone M.D. Susan E. Pogson R.T. 《Emergency radiology》1997,4(4):200-206
The purpose of this study was to evaluate the ability of helical computed tomographic angiography (HCTA) to detect vascular injury in penetrating neck trauma. Thirty-five patients (30 gunshot wounds and 5 stab wounds) were studied prospectively with HCTA. Scans were performed with a 5-mm slice thickness at a 1:1 pitch after injection of 90 ml of nonionic contrast medium (30-second delay) at 3 ml/sec. Results were compared with those for angiography (29), surgery (3), ultrasound (2), and local inspection (1). HCTA correctly revealed 19 normal and 10 abnormal studies. In 8 cases, HCTA revealed irregular vessel margins (3), contrast extravasation (2), lack of vascular enhancement (1), and caliber changes (2). In 2 patients, HCTA revealed indirect signs of injury only. In 6 cases, HCTA findings did not correlate with angiography. HCTA detects both direct and indirect signs of vascular injury. Although indirect findings are more sensitive, the direct evaluation of vessels increases the specificity and has a high negative predictive value. 相似文献
106.
The role of glutamate in conditioned taste aversion was investigated. Both, in the amygdala (AMYG) and in the lateral hypothalamus (LH) extracellular levels of glutamate were assessed by microdialysis and capillary electrophoresis with laser induced fluorescence detection. Rats were conditioned by pairing a novel flavor (strawberry flavor) with an intraperitoneal injection of lithium chloride. When the conditioned stimulus (strawberry flavored solution) was injected into the mouth of conditioned rats, there was an increase of glutamate release in the AMYG, and a decrease in glutamate release in the LH. These results predicted that glutamate release in the AMYG and the LH was involved in CTA. This possibility was tested by MK-801 (glutamate antagonist) and glutamate microinjections. MK-801 injections in AMYG attenuated the rejection of the novel flavor, and in the LH did not cause any effect on CTA. Glutamate microinjections in the AMYG caused CTA. These results suggest that glutamatergic activity in the AMYG might be a relevant neurochemical correlate and cause of conditioned taste aversion. 相似文献
107.
Pablo L. Joskowicz Alberto Muoz Julio Barrera Alejandro J. Müller 《Macromolecular chemistry and physics.》1995,196(1):385-398
Preparative temperature rising elution fractionation (TREF) on commercial linear low density polyethylene (LLDPE) and low density polyethylene (LDPE) samples has been performed. The resulting fractions exhibited a bimodal and a unimodal distribution, respectively. Two LLDPE fractions of low (5 CH3/1000 C) and high (21 CH3/1000 C) short-chain branching content were solution-mixed with the LDPE central fraction (16 CH3/1000 C). Indirect evidence based on differential scanning calorimetry results suggest that the fractions with similar branch contents are more miscible than those with dissimilar ones. 相似文献
108.
PURPOSE: To assess the dose-dependent effect of low concentrations of isoflurane on respiratory mechanics in normal subjects. METHODS: We studied 12 non-premedicated ASA I patients scheduled for lower abdominal or extremity surgery. After thiopental 5-7 mg*kg(-1) iv and succinylcholine 1 mg x kg(-1) iv, the trachea was intubated and an esophageal balloon was placed optimally by the occlusion test. After introduction of N(2)O and muscle paralysis with vecuronium, we studied 0, 0.6, 0.9 and 1.2% isoflurane. We recorded flow (F), airway opening and esophageal pressures. Signals were amplified, filtered, sampled at 100 Hz, and then fed in a 12-bit analogue-digital converter in a personal computer. Data were collected and analyzed using LABDAT and ANADAT software. Signals were acquired for 60-90 sec during mechanical ventilation (10 mL x kg(-1), 10 breaths x min(-1), I:E ratio 1:2). We estimated respiratory system (RS), lung (L) and chest wall (W) dynamic elastance (E) and resistance (R) by P(t) = EV(T)(t) + RF(t) + K, where t is time, V(T) tidal volume from integration of F, and K an estimation of end-expiratory pressure. ANOVA was used for comparing the basal state with the three concentrations. RESULTS: E and R were statistically lower at 0.6, 0.9 and 1.2% compared to basal values for RS, L and W. Concentrations equal to or higher than 0.6% did not further change respiratory mechanics, except for E(L1.2) compared to E(L0.6,) 12.37 +/- 5.72 and 13.52 +/- 5.64 cm H(2)O.L(-1), respectively. CONCLUSION: Isoflurane concentrations between 0.6-1.2% are not associated to a dose-dependent effect on respiratory mechanics. 相似文献
109.
Giovanni Battista Grossi Carlo Maiorana Rocco Alberto Garramone Andrea Borgonovo Luca Creminelli Franco Santoro 《Journal of oral and maxillofacial surgery》2007,65(5):901-917
PURPOSE: The purpose of this study was to identify the risk factors for severe discomfort after mandibular third molar surgery and to assess the validity of the Postoperative Symptom Severity (PoSSe) scale. PATIENTS AND METHODS: In a 2-year prospective study, a total of 255 unilateral impacted mandibular third molar teeth were surgically removed under local anesthesia by 3 surgeons. Standardized surgical and analgesic protocols were followed. At the review appointment, 1 week after surgery, all patients returned a completed follow-up questionnaire (PoSSe scale) and were evaluated clinically for postoperative pain (number of painkillers taken) and trismus (differences in mouth opening). Sixteen predictive variables were evaluated using stepwise logistic regression analysis to identify the risk factors associated with severe discomfort. RESULTS: Severe postoperative discomfort was predicted by these independent variables: gender, tobacco use, ramus relationship/space available, and antibiotic prophylaxis. Oral contraceptive use and operation time were not identified as risk factors. The patients' perceptions of the severity of symptoms (PoSSe scale score) was strongly correlated with clinical assessment of trismus (r = 0.54) and pain (r = 0.42). CONCLUSION: The PoSSe scale resulted in a valid and responsive measure of the severity of symptoms after surgical extraction of lower third molars and reflected the clinical severity of the postoperative discomfort. From a patient's perspective, operative factors had little bearing on the quality of life after removal of mandibular third molars. 相似文献