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排序方式: 共有1777条查询结果,搜索用时 15 毫秒
91.
Karpati PC Rossignol M Pirot M Cholley B Vicaut E Henry P Kévorkian JP Schurando P Peynet J Jacob D Payen D Mebazaa A 《Anesthesiology》2004,100(1):30-6; discussion 5A
BACKGROUND: Postpartum hemorrhage remains a major cause of global maternal morbidity and mortality, even in developed countries, despite the use of intensive care units. This study sought to (1) assess whether myocardial ischemia could be associated with and even aggravate hemorrhagic shock in young parturients admitted for postpartum hemorrhage, and (2) identify the independent risk factors for myocardial ischemia. METHODS: On their referral to the intensive care unit, a multidisciplinary team managed parturients with severe postpartum hemorrhage. Ventilation, transfusion, catecholamines, surgery, or angiography with uterine embolization were provided as clinically indicated. Plasma cardiac troponin I levels were used as a surrogate marker of acute myocardial injury and electrocardiograms of myocardial ischemia. RESULTS: A total of 55 parturients were referred with severe postpartum hemorrhage, all in hemorrhagic shock. Twenty-eight parturients (51%) had elevated serum levels of cardiac troponin I (9.4 microg/l [3.7-26.6 microg/l]), which were associated with electrocardiographic signs of ischemia and deteriorated myocardial contractility and correlated with the severity of hemorrhagic shock. Indeed, multivariate analysis identified low systolic and diastolic arterial blood pressure (< 88 and < 50 mmHg, respectively) and increased heart rate (> 115 beats/min) as independent predictors of myocardial injury. In addition, all patients who were given catecholamines also had elevated cardiac troponin I levels. CONCLUSIONS: These results suggest that treatment of postpartum hemorrhage-induced hemorrhagic shock should be coupled with concomitant prevention of myocardial ischemia, even in young parturients. 相似文献
92.
The effects of prolonged ambulation on labor with epidural analgesia 总被引:12,自引:0,他引:12
Frenea S Chirossel C Rodriguez R Baguet JP Racinet C Payen JF 《Anesthesia and analgesia》2004,98(1):224-229
Ambulation during labor is becoming more popular, although its impact on the progress of labor and on pain intensity remains unclear. We wondered whether prolonged ambulation with epidural analgesia had a possible effect on duration of labor and pain. In this prospective, randomized trial, 61 parturients with uncomplicated term pregnancies were allocated to be recumbent (n = 31) or to ambulate (n = 30). Epidural analgesia was provided with intermittent administrations of 0.08% bupivacaine-epinephrine plus 1 microg/mL of sufentanil. Of the 30 women assigned to the ambulatory group, 25 actually walked. Their ambulating time was 64 +/- 34 min (mean +/- SD), i.e., 29% +/- 16% of the first stage. There were no differences between the two groups in the length of labor and in pain visual analog scale scores. However, the ambulatory group received smaller doses of bupivacaine (6.4 +/- 2.2 mg/h versus 8.4 +/- 3.6 mg/h; P = 0.01) and of oxytocin (6.0 +/- 3.7 mUI/min versus 10.2 +/- 8.8 mUI/min; P < 0.05). A greater ability to void was also found in the ambulatory group (P < 0.01). Although the duration of labor and pain relief was unchanged, these findings support that ambulation during labor may be advantageous. IMPLICATIONS: This study compared the duration of labor and pain relief between parturients receiving epidural analgesia who were ambulated or were recumbent. Whereas walking had no impact on either duration of labor or pain relief, it was associated with a reduction in both bupivacaine and oxytocin requirements. 相似文献
93.
Neuropathic arthropathy of the spine is a destructive condition of the spine which is secondary to a loss of the protective proprioceptive reflexes. In the majority of cases, it occurs in patients who have suffered from traumatic medullary lesions and is responsible for destruction of the vertebral bodies and considerable spinal deformity. We report a case of neurogenic lumbar arthropathy in a patient with a spinal arteriovenous malformation. This vascular lesion caused considerable disturbances of proprioception. The course was favorable with regard to the deformity after correction and fusion by posterior approach. 相似文献
94.
Neuroepithelial dysembryoplastic tumor (DNT) is usually considered as a supratentorial benign neoplasm. DNT of the posterior fossa is a very rare entity and only four previous cases were reported in the literature. We describe a case of a 26-Year-old woman presenting recurrent episodes of vertigo. Magnetic resonance imaging revealed four cystic lesions located in the cerebellum, hypointense on T1-weighted images and hyperintense on T2-weighted images, without gadolinium enhancement. After partial resection, histological examination showed small glial cells, oligodendrocytes-like, lying in an eosinophilic alveolar matrix with some floating neurons. Due to this specific glioneuronal element, the diagnosis of DNT was retained. We discuss the clinical and radiological particularities of this infratentorial location and compare our case with those previously described in the literature. 相似文献
95.
Peripheral muscle endurance and the oxidative profile of the quadriceps in patients with COPD
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BACKGROUND: Based on previously reported changes in muscle metabolism that could increase susceptibility to fatigue, we speculated that patients with chronic obstructive pulmonary disease (COPD) have reduced quadriceps endurance and that this will be correlated with the proportion of type I muscle fibres and with the activity of oxidative enzymes. METHODS: The endurance of the quadriceps was evaluated during an isometric contraction in 29 patients with COPD (mean (SE) age 65 (1) years; forced expiratory volume in 1 second 37 (3)% predicted) and 18 healthy subjects of similar age. The electrical activity of the quadriceps was recorded during muscle contraction as an objective index of fatigue. The time at which the isometric contraction at 60% of maximal voluntary capacity could no longer be sustained was used to define time to fatigue (Tf). Needle biopsies of the quadriceps were performed in 16 subjects in both groups to evaluate possible relationships between Tf and markers of muscle oxidative metabolism (type I fibre proportion and citrate synthase activity). RESULTS: Tf was lower in patients with COPD than in controls (42 (3) v 80 (7) seconds; mean difference 38 seconds (95% CI 25 to 50), p<0.001). Subjects in both groups had evidence of electrical muscle fatigue at the end of the endurance test. In both groups significant correlations were found between Tf and the proportion of type I fibres and citrate synthase activity. CONCLUSION: Isometric endurance of the quadriceps muscle is reduced in patients with COPD and the muscle oxidative profile is significantly correlated with muscle endurance. 相似文献
96.
Misino J Lavis JF Tardif A Peron JM 《Revue de stomatologie et de chirurgie maxillo-faciale》2004,105(6):317-321
BACKGROUND: The aim of our study was to assess the long term follow-up in six patients who all presented with solitary cysts and underwent minor surgery. At follow-up treatment (range 16 months to 18 years) efficacy was evaluated and screened for any possible future complications. MATERIAL AND METHODS: Since 1985 all patients who presented in the Department of oral and Maxillo-Facial Surgery with a simple bone cyst were retrospectively included in the study. A total of only 6 patients underwent surgery. One patient with a condylar cyst was seen with a delay of 16 months. The others were examined over 5 years. RESULTS: Surgery allowed us to confirm the diagnosis and achieve the treatment of the cyst. One patient who had a cyst in the ramus and was re-operated for a follicular cyst adjacent to the wisdom tooth. No complication or recurrence was observed. 相似文献
97.
98.
De Salvatore G Desaphy JF Piepoli AL Natale L De Salvia MA Mitolo CI Renna G Conte-Camerino D Mitolo-Chieppa D 《Autonomic & autacoid pharmacology》2004,24(2):45-54
1. Prolonged bed rest or exposure to microgravity may cause several alterations in autonomic nervous system response (ANSR). 2. Hindlimb unloading (HU) rats were used as an animal model of simulated microgravity to investigate ANSR changes. The experiments were carried out to investigate the effects of simulated microgravity on the autonomic nervous response of the perfused mesenteric vascular bed (MVB), vas deferens and the colon and duodenum from 2-week HU rats. 3. In MVB preparations of HU rats, the frequency-dependent increases in perfusion pressure with perivascular nerve stimulation (PNS; 8-40 Hz) were inhibited, whereas the noradrenaline (NA) concentration-dependent (1-100 microM) perfusion pressure increases were potentiated. The latter most probably reflected up-regulation of alpha-adrenergic receptor function. Relaxant responses of NA-precontracted MVB to PNS (4-30 Hz) or isoprenaline were not different between control and HU preparations, while vasodilation induced by the endothelial agonist ACh was reduced. 4. Transmural stimulation (2-40 Hz) induced frequency-dependent twitches of the vas deferens which were reduced in vas deferens of HU rats, while the sensitivity to NA-induced contraction was significantly increased. 5. In the gastroenteric system of HU rat, direct contractile responses to carbachol or tachykinin as well as relaxant or contractile responses to nervous stimulation appeared unchanged both in the proximal colon rings and in duodenal longitudinal strips. 6. In conclusion, HU treatment affects peripheral tissues in which the main contractile mediators are the adrenergic ones such as resistance vessels and vas deferens, probably by reducing the release of neuromediator. This study validates NA signalling impairment as a widespread process in microgravity, which may most dramatically result in the clinical phenotype of orthostatic intolerance. 相似文献
99.
100.
Chen YM Perng RP Shih JF Lee YC Lee CS Tsai CM Whang-Peng J 《British journal of cancer》2004,90(2):359-365
Cyclooxygenase-2 (COX-2) expression is increased in breast cancer and surgery has been shown to increase the growth of metastatic tumours. We investigated the effect of selective COX-2 inhibition on the growth of metastases in either an experimental metastasis model or following excision of a murine primary breast tumour. 50,000 4T1 mammary carcinoma cells were injected into the mammary fat pad of female BALB/c mice. When the mean TD reached 8+/-0.4 mm, tumours were excised and the mice were randomised into two groups (n=12 per group) to receive daily intraperitoneal injections of the selective COX-2 inhibitor, SC-236 or drug vehicle for 14 days. Alternatively, experimental metastases were established by tail-vein injection of 50,000 4T1 cells. Mice received either the selective COX-2 inhibitor, SC-236 or drug vehicle for 14 days (n=12 per group). SC-236 treatment significantly reduced tumour burden, the number and size of spontaneous metastases following primary tumour excision. SC-236 treatment also reduced tumour burden, the number and size of experimental metastases. Immunohistochemical staining demonstrated that COX-2 inhibition reduced microvessel density and increased apoptosis within both spontaneous and experimental metastases. These data clearly demonstrate that the selective COX-2 inhibitor, SC-236, has potent antimetastatic activity against both spontaneous metastases arising following primary tumour excision and experimental metastases. 相似文献