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1.
Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA.  相似文献   
2.
Human histocompatibility leukocyte antigen E (HLA-E) and mouse major histocompatibility complex (MHC) class Ib antigen, Qa-1, share the same substitutions at two normally conserved positions 143 and 147, which are likely to affect binding of the C terminus of peptides. Qa-1 is able to bind a peptide derived from the leader sequence of H-2 D and H-2 L molecules. We developed a peptide binding assay in vitro to compare the binding specificity of HLA-E with the mouse MHC class Ib molecule Qa-1. We demonstrate that HLA-E binds, although poorly, the peptide which binds to Qa-1 and that it also binds nonamer signal sequence-derived peptides from human MHC class I molecules. Using alanine and glycine substitutions, we could define primary anchor residues at positions 2 and 9 and secondary anchor residues at position 7 and possibly 3.  相似文献   
3.
The anticholinergic effect of atropine, imipramine, clomipramine and metapramine was evaluated on oxotremorine induced trembling in the mouse as well as on contractions of the isolated guinea pig ileum induced by electrical stimulation of the mesenteric plexus. The ED 50 and IC 50 which expressed the anticholinergic activity of these substances, were found to be identifically distributed for both methods. Activity, in decreasing order was found to be: atropine much greater than imipramine greater than clomipramine greater than metapramine. There was a good correlation between results from the two methods (r = 0.97). The method using the stimulated guinea pig ileum would therefore seem suitable for characterisation of potential anticholinergic activity of a molecule.  相似文献   
4.
OBJECTIVE: Sleeve lobectomy is a widely accepted procedure for central tumors for which the alternative is pneumonectomy. The purpose of this study is to assess operative mortality, morbidity, and long-term results of sleeve lobectomies performed for non-small cell lung carcinoma (NSCLC). METHODS: A retrospective review of 218 patients who underwent sleeve lobectomy for NSCLC between 1981 and 2005 was undertaken. There were 186 (85%) men and 32 women with a mean age of 61.9 years (range, 19-82 years). Eighty patients (36.6%) had a preoperative contraindication to pneumonectomy. Right upper lobectomy was the most common operation (45.4%). Vascular sleeve resection was performed in 28 patients (12.8%) and was commonly associated with left upper lobectomy (n=20; 9.1%; p=0.0001). The histologic type was predominantly squamous cell carcinoma (n=164; 75%), followed by adenocarcinoma (n=46; 21%). Resection was incomplete in nine (4.1%) patients. RESULTS: There were nine operative deaths; the operative mortality and the morbidity rates were 4.1% and 22.9%, respectively. A total of 14 (6.4%) patients presented with bronchial anastomotic complications: two were fatal postoperatively, seven patients required reoperation, three required a stent insertion, and two were managed conservatively. Multivariate analysis showed that compromised patients (p=0.001), current smoking (p=0.01), right sided resections (p=0.003), bilobectomy (p=0.03), squamous cell carcinoma (p=0.03), and presence of N1 or N2 disease (p=0.01) were risk factors for mortality and morbidity. Follow-up was complete in 208 patients (95.4%). Overall 5-year and 10-year survival rates were 53% and 28.6%, respectively. After complete resection, recurrence was local in 10 patients, mediastinal in 20, and distant in 25. By multivariate analysis, two factors significantly and independently influenced survival: nodal status (N0-N1 vs N2; p=0.01) and the stage of the lung cancer (stage I-II vs III, p=0.02). CONCLUSIONS: For patients with NSCLC, sleeve lobectomy achieves local tumor control, even in patients with preoperative contraindication to pneumonectomy and is associated with low mortality and bronchial anastomotic complication rates. Postoperative complications are higher in compromised patients, smokers, N disease, right sided resections, bilobectomies, and squamous cell cancers. The presence of N2 disease and stage III significantly worsen the prognosis.  相似文献   
5.
Results of three therapeutic modalities used for the treatment of a homogeneous series of patients with a Pouteau Colles fracture are analyzed. Orthopedic treatment provided deceiving results. Pinning was, on the contrary, very effective, intrafocal pinning with immediate mobilization of the wrist appearing perfectly effective. Few complications were reported in contrast to plastered immobilizations. Good results were obtained in 80% of cases and functional recovery was rapid, indicating that this method represents undoubted progress when compared with conventional therapies.  相似文献   
6.
7.
OBJECTIVE: To evaluate how Belgian health care providers deal with a request for emergency contraception. METHOD: In 2002-2003 we conducted 12 focus groups with pharmacists, general practitioners and school physicians. A skilled moderator accompanied by an observer conducted the focus groups using a semi-structured screenplay. RESULTS: All these health care providers agree with the free access to emergency contraception (EC), but experience considerable frustration with regard to the practical aspects and the legal framework. General practitioners (GPs) claim to spend a lot of time on requests for EC and they are concerned about the quality of the counselling provided in pharmacies. Pharmacists are creative when giving counselling in the pharmacy, but there is, nevertheless, a problem with a lack of privacy. School physicians are frustrated that there is no legal possibility to respond to a request for EC when they feel they are ideally placed to advise adolescents. CONCLUSION: The over-the-counter sale of EC offers women better access, but many barriers still interfere with optimal care. Pharmacists experience a lack of skills to communicate with adolescents and a lack of privacy to give counselling. GPs have good intentions, but are confronted with a lack of willingness on the part of the patients and also financial barriers. School physicians want more possibilities to help adolescents.  相似文献   
8.
Regional cerebral blood flow (rCBF) changes in cortical motor areas were measured during a movement of the dominant right hand in 15 patients with Parkinson's disease deprived of their usual levodopa treatment, in 11 patients with Parkinson's disease undergoing long-term treatment with levodopa, and in 15 normal volunteers. The supplementary motor areas were significantly activated in the normal subjects and in the patients receiving levodopa but not in the patients deprived of levodopa. The contralateral primary sensory motor area was significantly activated in all three groups. The ipsilateral primary sensory motor cortex was not activated in the normal subjects and the non-treated patients but was in the patients treated with levodopa. It is concluded that the supplementary motor area hypoactivation which is observed in akinetic non-treated patients with Parkinson's disease is not present in patients undergoing long-term treatment with levodopa. This result suggests that (a) levodopa improves the functional activity of supplementary motor areas in Parkinson's disease and (b) there is no pharmacological tolerance to this effect. The ipsilateral primary motor cortex activation observed in the patients treated with levodopa could be related to levodopa-induced abnormal involuntary movements.  相似文献   
9.
Hepatic oil embolism following lymphography is reported in a 68-year-old man admitted for chylous ascites associated with recurrent prostatic carcinoma. Abdominal plain radiography, CT, and ultimately liver biopsy strongly support a direct lymphatic pathway and are against the role of lymphaticovenous anastomoses generally advocated to explain this phenomenon.  相似文献   
10.
 The ability voluntarily to stabilize the head in space during lateral rhythmic oscillations (0.59±0.09 Hz) of the trunk has been investigated during microgravity (μG) and normal gravity (nG) conditions (parabolic flights). Five healthy young subjects, who gave informed consent, were examined. The movements were performed with eyes open or eyes closed, during phases of either μG or nG. The main result was that head orientation with respect to vertical may be stabilized about the roll axis under μG with, as well as without vision, despite the reduction in vestibular afferent and muscle proprioceptive inputs. Moreover, the absence of head stabilization about the yaw axis confirms that the degrees of freedom of the neck can be independently controlled, as was previously reported. These results seem to indicate that voluntary head stabilization does not depend crucially upon static vestibular afferents. Head stabilization in space may in fact be organized on the basis of either dynamic vestibular afferents or a short-term memorized postural body schema. Received: 4 October 1995 / Accepted: 30 September 1996  相似文献   
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