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81.
From January 1981 through October 1995, a total of 28 patients underwent surgery for metastatic lung tumors in our institute. A retrospective review and survival analysis of these patients are reported. There were 12 males and 16 females, with the mean age of 57 years. Of them, 20 patients had solitary lesions. Pulmonary metastasis was from the colon in 8 patients, from the breast in 5, from the stomach and the uterus in each 3, from the bladder, the rectum and the soft tissue in each 2, and from the kidney, the ovarium and the thyroid in each 1. A lobectomy was performed in 22 patients, 17 of whom were accompanied with mediastinal lymph node dissection (R2a). Partial resection without lymph node dissection was performed in 6 patients (R0). Overall 5-year survival was 24.7%. Four-year or over survivor were 4 patients who underwent a lobectomy with R2a. The patients undergoing lobectomy had a significantly better prognosis compared with patients with partial resection (p<0. 05). The patients with R2a had significantly less local recurrence than patients with R1 or R0 (p<0.05). We conclude that lobectomy with R2a is suitable treatment for metastatic lung cancer.  相似文献   
82.
Nerve root stimulation may be employed in patients with motor neuron disease (MND) to rule out motor neuropathy with conduction block. The diagnostic utility of these studies is unknown, in part because the range of amplitude changes across nerve root segments in patients with active neuronal degeneration has not been well studied. We reviewed root stimulation studies in 32 patients (59 nerves) with MND and found segmental amplitude reduction from 0 to 45%, a range similar to values reported for normal subjects; there was no suggestion of conduction block based on our usual criteria.  相似文献   
83.
We performed 73 kidney transplants in 51 patients with steroid-resistant nephrotic syndrome (SRNS) with focal segmental glomerular sclerosis (FSG) ages 18.4 +/- 12.8 (mean +/- SD) years. Recurrence of SRNS, defined by rapid onset of proteinuria, hypoalbuminemia and/or > 95% epithelial cell foot process effacement with or without the presence of FSG, occurred in 26 grafts in 16 patients. Acute renal failure (ARF) occurred in 16 of 26 (61.5%) grafts with recurrence versus 7 of 47 (14.9%) grafts without recurrence (P < 0.0001). ARF occurred in 4 of 9 (44.4%) living-related donor (LRD) recipients with recurrence and 3 of 21 (12.5%) LRD recipients without recurrence (NS). ARF in cadaver donor (CAD) recipients with recurrence was 12 of 17 (70.5%) versus 4 of 23 (17.4%) without recurrence (P < 0.0001). ARF was also higher in LRD or CAD with recurrence than in a control group of non-SRNS patients matched for age, sex and time of transplantation. Graft survival at one year was lower in patients with recurrence and ARF [4 of 16 (25%)] compared to patients with recurrence and no ARF [9 of 11 (82%), P < 0.01]. There was no difference in graft survival in patients without recurrence who did or did not have ARF. One or more acute rejection episodes occurred in all 16 patients with ARF and recurrence, in all 7 patients with ARF without recurrence, and in 7 of 10 patients with recurrence without ARF compared with only 11 of 40 (28%) of patients with neither recurrence nor ARF (P < 0.0001, < 0.001 and < 0.04, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
84.
Effect of sodium hypochlorite disinfection of impressions on the size and quality of plaster models is studied. Twenty-minute submerging of silicone impressions in 0.5% sodium hypochlorite solution did not change their size and did not deteriorate the quality of surface and hardness of plaster models. Stomalgin impressions cannot be disinfected by sodium hypochlorite solution because of expressed destructive effect of this disinfectant on the impressions.  相似文献   
85.
86.
Rats were given suction lesions of the presumptive frontal cortex on embryonic day 18 (E18) and subsequently tested, as adults, on tests of spatial navigation (Morris water task, radial arm maze), motor tasks (Whishaw reaching task, beam walking), and locomotor activity. Frontal cortical lesions at E18 affected cerebral morphogenesis, producing unusual morphological structures including abnormal patches of neurons in the cortex and white matter as well as neuronal bridges between the hemispheres. A small sample of E18 operates also had hydrocephaly. The animals with E18 lesions without hydrocephalus were behaviorally indistinguishable from littermate controls. The results demonstrate that animals with focal lesions of the presumptive frontal cortex have gross abnormalities in cerebral morphology but the lesions leave the functions normally subserved by the frontal cortex in adult rats unaffected. The results are discussed in the context of a hypothesis regarding the optimal times for functional recovery from cortical injury.  相似文献   
87.
The recovery from prior stimulation of the compound action potential (CAP) was measured using a forward masking stimulus paradigm in four normal-hearing, human subjects. The CAP was recorded using a wick electrode placed on the tympanic membrane. The effects of a 4000-Hz, 97-dB SPL conditioning stimulus on CAP amplitude in response to a 4000-Hz probe were measured as a function of conditioner-probe interval for three probe levels. The normalized probe response amplitude was completely recovered to the control values at an average conditioner-probe interval of 1359 ms, similar to that observed in chinchilla (Relkin, E.M., Doucet, J.R., Sterns, A., 1995. Recovery of the compound action potential following prior stimulation: evidence for a slow component that reflects recovery of low spontaneous-rate auditory neurons, Hear. Res. 83, 183-189). The present results are interpreted as a consequence of the slow recovery of low spontaneous-rate (SR), high threshold neurons from prior stimulation (Relkin, E.M., Doucet, J.R., 1991. Recovery from prior stimulation. I: Relationship to spontaneous firing rates of primary auditory neurons. Hear. Res. 55, 215-222) and may provide indirect physiological evidence for the existence of a class of low-SR auditory neurons in humans.  相似文献   
88.
OBJECTIVE: To investigate the regulation of expression of the angiogenic cytokine vascular endothelial growth factor (VEGF) in rheumatoid arthritis (RA), in order to determine whether new blood vessel formation could be a potential therapeutic target in RA. METHODS: Dissociated RA synovial membrane cells were cultured in the presence of cytokine inhibitors, or under hypoxic conditions. Serum VEGF levels were serially measured in RA patients enrolled in clinical trials of anti-tumor necrosis factor alpha (anti-TNFalpha) monoclonal antibody treatment. RESULTS: Combined neutralization of TNFalpha and interleukin-1 (IL-1) in RA synovial membrane cultures reduced VEGF release by 45% (P < 0.05 versus control), although blockade of either TNFalpha or IL-1 activities alone resulted in only small inhibitory effects. In addition, release of VEGF from RA synovial membrane cells was selectively up-regulated by hypoxia. Serum VEGF levels were significantly elevated in RA patients relative to control subjects, and correlated with disease activity. Treatment of RA patients with anti-TNFalpha significantly decreased serum VEGF, and this effect was enhanced by cotreatment with methotrexate. CONCLUSION: Inhibition of TNFalpha and IL-1 activity in vivo could reduce the drive to new blood vessel formation, and hence pannus mass, adding to other therapeutic effects of anti-TNFalpha therapy in RA.  相似文献   
89.
Methods of both linkage analysis and association analysis may be model-based or model-free. The former are useful for initial exploratory analysis, the latter for more detailed multivariate genometric analysis. Linkage leads to an association, but that association may be solely intrafamilial. Allelic association may be due to pleiotropy, linkage disequilibrium, meiotic drive, selection, or population stratification. Using non-transmitted parental alleles as controls for alleles transmitted to cases, in conjunction with a McNemar-type test, does not detect association in the absence of linkage. Model-based analyses should use models that approximate the complexity of the disease being studied in order to be both robust and powerful.  相似文献   
90.
Lens major intrinsic protein (MIP) is the founding member of the MIP family of membrane channel proteins. Its isolation from ovine lens fibre cell membranes and its two-dimensional crystallization are described. Membranes were solubilized with N-octyl-beta-D-glucoside and proteins fractionated by sucrose gradient centrifugation containing decyl-beta-D-maltoside. MIP was purified by cation exchange chromatography, and homogeneity was assessed by mass analysis in the scanning transmission electron microscope. Purified MIP reconstituted into a lipid bilayer at a low lipid-to-protein ratio formed highly ordered tetragonal two-dimensional crystals. The square unit cell had a side length of 6.4 nm, and exhibited in negative stain four stain-excluding elongated domains surrounding a central stain-filled depression. Projection maps of freeze-dried crystals exhibited a resolution of 9 A, and revealed a monomer structure of MIP consisting of distinct densities. Despite significant differences in the packing of tetramers in the crystals, the projection map of the MIP monomer was similar to that of aquaporin-1 (AQP1), the first member of the MIP family which had its structure resolved to 6 A. Our protocols for the purification and reconstitution of MIP establish the feasibility for future work to visualize structure elements which determine the diverse functional properties of the MIP family members.  相似文献   
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