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Functional imaging studies in normal humans have shown that the supplementary motor area (SMA) and the primary motor cortex (PMC) are coactivated during various breathing tasks. It is not known whether a direct pathway from the SMA to the diaphragm exists, and if so what properties it has. Using transcranial magnetic stimulation (TMS) a site at the vertex, representing the diaphragm primary motor cortex, has been identified. TMS mapping revealed a second area 3 cm anterior to the vertex overlying the SMA, which had a rapidly conducting pathway to the diaphragm (mean latency 16.7 ± 2.4 ms). In comparison to the vertex, the anterior position was characterized by a higher diaphragm motor threshold, a greater proportional increase in motor-evoked potential (MEP) amplitude with voluntary facilitation and a shorter silent period. Stimulus–response curves did not differ significantly between the vertex and anterior positions. Using paired TMS, we also compared intracortical inhibition/facilitation (ICI/ICF) curves. In comparison to the vertex, the MEP elicited from the anterior position was not inhibited at short interstimulus intervals (1–5 ms) and was more facilitated at long interstimulus intervals (9–20 ms). The patterns of response were identical for the costal and crural diaphragms. We conclude that the two coil positions represent discrete areas that are likely to be the PMC and SMA, with the latter wielding a more excitatory effect on the diaphragm.  相似文献   
123.
Objective To evaluate the possibility of preservation of the larynx after neoadjuvant chemotherapy by performing a conservative surgery instead of total laryngectomy initially planned, in patients with previously untreated laryngeal and piriform sinus squamous cell carcinoma (SCC). Study Design Retrospective study. Methods A total of 115 patients treated at Tenon Hospital with induction chemotherapy from 1985 to 1995, all with initial indication of radical surgery, were available for the study. The clinical tumor response was evaluated after three cycles of chemotherapy. According to this response, to preserve laryngeal functions, some patients had a modification of the treatment initially planned: radiation therapy essentially for complete responders, and conservative surgery for some partial responders. Results Of 69 patients with laryngeal cancer, 14 were treated by partial laryngectomy and 19 by radiation therapy; of 46 patients with piriform sinus cancer, 8 were treated by partial surgery and 12 by radiation therapy; the other patients were treated as was initially planned (total laryngectomy with partial pharyngectomy). Overall survival rates, estimated by the Kaplan‐Meier method, were not statistically different between the three treatment groups. The laryngeal functions were preserved in 54% of the patients who were alive at 3 years. Conclusion This report is a retrospective study, but these results suggest the possibility of using conservative surgery, instead of initially planned total laryngectomy, for good responders to induction chemotherapy with a small residual tumor.  相似文献   
124.
Chronic hepatitis C virus (HCV) infections compromise natural killer (NK)-cell immunity. Direct-acting antivirals (DAA) effectively eliminate HCV, but the long-term effects on NK cells in cured patients are debated. We conducted a proteomic study on CD56+ NK cells of chronic HCV-infected patients before and 1 year after DAA therapy. Donor-variation was observed in NK-cell proteomes of HCV-infected patients, with 46 dysregulated proteins restored after DAA therapy. However, 30% of the CD56+ NK-cell proteome remained altered 1 year post-therapy, indicating a phenotypic shift with low donor-variation. NK cells from virus-negative cured patients exhibited global regulation of RNA-processing and pathways related to “stimuli response”, “chemokine signaling”, and “cytotoxicity regulation”. Proteomics identified downregulation of vesicle transport components (CD107a, COPI/II complexes) and altered receptor expression profiles, indicating an inhibited NK-cell phenotype. Yet, activated NK cells from HCV patients before and after therapy effectively upregulated IFN-γ and recruited CD107a. Conversely, reduced surface expression levels of Tim-3 and 2B4 were observed before and after therapy. In conclusion, this study reveals long-term effects on the CD56+ NK-cell compartment in convalescent HCV patients 1 year after therapy, with limited abundance of vesicle transport complexes and surface receptors, associated with a responsive NK-cell phenotype.  相似文献   
125.
Commonly used frontobasal approaches for microsurgical removal of olfactory groove meningiomas have certain disadvantages, such as late exposure of the neurovascular complex located dorsal to the tumor, namely, the internal carotid artery, middle cerebral artery, anterior cerebral artery, and the optic nerves. In addition, the frontal sinuses are frequently opened and there can be compression of the frontal lobes from significant spatula pressure. We report our experience with the pterional approach for these tumors in 28 patients. All patients presented with hyposmia/anosmia; 20 had personality changes and 8 had visual deficits. At surgery, after dissection of the sylvian fissure, the internal carotid artery, middle cerebral artery, anterior cerebral artery, and the homolateral optic nerve were exposed before removal of the posterior tumor parts. Reduction of focal pressure was achieved by removal of the contralateral tumor following partial resection of the falx and crista galli. Total tumor removal was obtained in all but 1 patient. One patient died of pulmonary embolism. The psychoorganic syndrome resolved in all but 1 patient; visual deficits improved in 6 patients. There were no postoperative infections. We consider the pterional approach to be superior to others for these lesions because it provides early exposure of the neurovascular complex, preservation of the frontal venous drainage, and avoidance of postoperative cerebrospinal fluid fistulae.  相似文献   
126.
Although consumers have made significant gains in having their voices heard in several areas within mental health, they have made less progress in being able to collaborate with their own treaters in setting treatment goals. On the basis of several years of groundwork by staff at the Connecticut Mental Health Center (CMHC), the Patient Care Committee conducted a needs assessment of providers and consumers to assess both groups' current involvement, interest in, and attitudes toward collaborative treatment planning. The results indicate that providers tend to place much of the responsibility for the difficulties in implementing collaborative treatment planning on consumers. Also, providers tend to underestimate consumers' interest in participating in this process. Implications of these findings for the development of an agency-wide training to enhance the collaborative nature of treatment planning are discussed.  相似文献   
127.
OBJECTIVES: Organic acid anhydrides are potential sensitisers and cause occupational airway diseases. In an intervention study the efficacy of measures of hygiene at the workplace and possible selection bias were investigated. METHODS: A first investigation with 110 workers exposed to hexahydrophthalic acid anhydride (HHPA) and methyltetrahydrophthalic acid anhydride (MTHPA) was carried out in July 1991. The results (skin prick test, specific serum IgE) showed that 20 people were sensitised, and in a challenge test the clinical relevance of the sensitisation was confirmed in six subjects. In December 1991, the hygiene conditions at the plant were improved. In November 1995 a second investigation of 84 people was performed (anamnesis, skin prick test, specific IgE, spirometry, and ambient and biological monitoring). The 27 people who had left the plant in the meantime were asked their reasons for leaving. RESULTS: The relative risk of people sensitised in 1991 of leaving the plant between 1991 and 1995 was 2.6 (95% confidence interval (95% CI) 1.4 to 4.9) compared with people without any sign of sensitisation. The percentage of people identified as sensitised in 1991, who were still working at the plant and came to the second investigation, was higher than for people without evidence of sensitisation (10/10 v 47/73; p < 0.05). In all the 10 sensitised people in 1991 the findings of the first investigation were confirmed in 1995. The rate of sensitisation in 1995 was 21%. None of the six people employed after 1991 showed evidence of sensitisation. Of the six people with clinically relevant sensitisation confirmed by a challenge test in 1991, five were still at their workplace. From 1991 they were only exposed to MTHPA at a reduced concentration (< 0.5-36 micrograms/m3 in 1995). All of them reported fewer symptoms than in 1991. No signs of bronchial obstruction were detected by spirometry at the workplace. CONCLUSIONS: In cross sectional studies there is a selection bias with a risk of underestimating the incidence of allergic diseases. The results further suggest that the improved hygiene conditions probably had a positive effect on the symptoms in sensitised people.  相似文献   
128.
The technique applied for external ventriculostomy should allow simple, fast, stable and clean performance of this procedure. The stepwise development of a metallic ventriculostomy kit should help overcome shortcomings of traditional methods of external ventriculostomy such as catheter obstruction and propensity for infection. A rigid ventriculostomy set for precoronary puncture was developed, consisting of a screw with selfbiting conical thread and a cannula with distal holes for CSF drainage. The rate of infection was < 2% in nonseptic patients with a mean duration of the ventriculostomy of 11 days (maximum: 2 months). Hemorrhage occurred in 1% of patients. Problems were secondary wound healing after prolonged periods with ventriculostomy in place and rapid CSF-infection in cases of loosened screws which were not instantly removed. Ventriculostomy can be performed bedside within 5 min and clotted cannulas can be exchanged via the indwelling screw. The system can be resterilized and the titanium device is MRI-compatible. The method tested compares favorably with conventional techniques of external ventriculostomy. Use of the system requires continuous education of the personnel involved in order to avoid complications such as hemorrhage and loosening of the screw.  相似文献   
129.
130.
PURPOSE: To report that silicone oil may be safely removed from immuno-recovered patients with acquired immunodeficiency syndrome (AIDS) after instillation for cytomegalovirus (CMV)-related rhegmatogenous retinal detachment. METHOD: We report two patients with CMV-related retinal detachment who had previously been treated with vitrectomy and silicone oil. RESULTS: Six months after removal of silicone oil, the retina remained attached in both patients. Without specific anti-CMV therapy, there was no relapse of CMV retinitis while patients were undergoing highly active antiretroviral therapy. Best-corrected visual acuity improved in both patients. CONCLUSION: It appears to be possible to remove silicone oil safely from patients with AIDS who show immune recovery, thus avoiding side effects of long-standing silicone oil and increasing quality of life. After silicone oil removal, visual acuity was improved.  相似文献   
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