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61.
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After partial or total esophagectomy, total gastrectomy, pancolectomy, and urinary cystectomy, it becomes necessary to reestablish continuity and/or replace function by the creation of a substitute organ obtianed from the various portions of the gastrointestinal tract. Ideally, the creation of the substitute organ should be undertaken at the same operation in which the original organ is excised. At times, however, the surgeon may elect a two-stage approach by replacing the afflicted organ during a separate operation either prior to or after excision, as dictated by the circumstances surrounding each individual patient. The use of stapling instruments has greatly facilitated the precision, neatness, and speed with which substitute organs can be constructed. This is especially spectacular in those patients in whom a one-stage procedure is elected.  相似文献   
63.
Unstimulated rabbits were sacrificed and their lungs washed with heparinized saline. After alveolar macrophages were harvested, the cell-free lavage fluid was centrifuged at 47,000 X g to recover a small, whitish, surface-active pellet (F fraction.) The supernatant was concentrated 15-fold by vacuum dialysis (P fraction). Alveolar macrophages in a serum-free system were challenged with radiolabeled (32P) Staphylococcus aureus preincubated in either balanced salt solution or F or P fraction. A small increase in alveolar macrophage bacterial uptake occurred with P fraction-treated staphylococci. P fraction from locally immunized animals further enhanced phagocytosis. In bactericidial experiments, alveolar macrophages were allowed to phagocytize staphylococci preincubated in either balanced salt solution or F fraction. Intracellular bactericidal activity of alveolar macrophages was quantitated by lysotaphin lysis of extracellular bacteria and quantitation of viable intracellular bacteria. Enhanced lung macrophage bactericidal activity against F fraction-incubated staphylococci was noted.  相似文献   
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The Differential Straight Arch technique, more commonly known as "Tip-Edge" (TP Orthodontics Inc.), uses a modified edgewise type bracket to allow differential tooth movement. As bracketed teeth incline toward their finishing positions, the geometry of the arch wire slot causes the vertical slot dimension available to the arch wire to increase. Advantage has been taken of this facility, to evolve an entirely new torquing system for final finishing, during the root correction phase. Instead of increasing rectangular arch wire size to fit the arch wire slot, as with conventional edgewise brackets, the Tip-Edge method reduces the vertical arch wire slot dimension to achieve a precise, three-dimensional relationship to a full-sized rectangular arch wire. The active component is provided by auxiliary springs. The method, which awaits mathematical analysis, is described and illustrated with two case reports.  相似文献   
67.
Neuronal intranuclear inclusions are found in the brains of patients with Huntington's disease and form from the polyglutamine-expanded N-terminal region of mutant huntingtin. To explore the properties of inclusions and their involvement in cell death, mouse clonal striatal cells were transiently transfected with truncated and full-length human wild-type and mutant huntingtin cDNAs. Both normal and mutant proteins localized in the cytoplasm, and infrequently, in dispersed and perinuclear vacuoles. Only mutant huntingtin formed nuclear and cytoplasmic inclusions, which increased with polyglutamine expansion and with time after transfection. Nuclear inclusions contained primarily cleaved N-terminal products, whereas cytoplasmic inclusions contained cleaved and larger intact proteins. Cells with wild-type or mutant protein had distinct apoptotic features (membrane blebbing, shrinkage, cellular fragmentation), but those with mutant huntingtin generated the most cell fragments (apoptotic bodies). The caspase inhibitor Z-VAD-FMK significantly increased cell survival but did not diminish nuclear and cytoplasmic inclusions. In contrast, Z-DEVD-FMK significantly reduced nuclear and cytoplasmic inclusions but did not increase survival. A series of N-terminal products was formed from truncated normal and mutant proteins and from full-length mutant huntingtin but not from full-length wild-type huntingtin. One prominent N-terminal product was blocked by Z-VAD-FMK. In summary, the formation of inclusions in clonal striatal cells corresponds to that seen in the HD brain and is separable from events that regulate cell death. N-terminal cleavage may be linked to mutant huntingtin's role in cell death.  相似文献   
68.
We report clinical, EEG and neuroimaging findings of three patients in two Italian families with merosin-negative congenital muscular dystrophy (CMD), drug-resistant occipital epilepsy, diffuse persistent cerebral white matter changes and focal cortical dysplasia. Clinical and epilepsy histories, EEG and neuroimaging findings were very similar in all patients. Seizures started in childhood and mainly consisted of periodic spasms, a particular type of partial seizure characterized by clusters of epileptic spasms. The motor expression of the spasms was very mild so that they had been frequently missed or misinterpreted as non-convulsive generalized absence seizures. Interictal EEG showed occipital spike-waves and bilateral synchronous slow spike-wave discharges. Ictal EEG showed prolonged periodic sequences of slow waves with associated fast rhythm complexes, characteristic of periodic spasms. Two patients had normal intelligence, one patient presented moderate mental retardation. Focal cortical dysplasia in the posterior areas of the brain, in addition to marked diffuse white matter alterations, was detected in the magnetic resonance images of all patients. Findings in these patients indicate that in merosin-negative CMD brain involvement can include cortical dysplasia, in addition to white matter changes. In such cases the brain damage can lead to a childhood-onset localization-related symptomatic occipital epilepsy. Epileptic seizures and cortical dysplasia can be, however, difficult to detect in CMD. The clinical semiology of epileptic seizures may in fact be modified because of muscular weakness. This implies that epilepsy may be misdiagnosed or even missed and EEG-polymyographic recordings may be necessary to identify it. Similarly, cortical dysplasia may be very localized and visible by neuroimaging only if it is carefully investigated on the basis of epileptological and EEG-polymyographic findings.  相似文献   
69.
Changes in steady-state fluorescence anisotropy of 1 -(4-trimethylaminophenyl)-6-phenyl-1,3,5-hexatriene TMA-DPH) are applied to the detection of lamellar-hexagonal transitions in egg phosphatidylethanolamine. Even low (2 mole%) proportions of diacylglycerol decrease the hexagonal transition temperature considerably, as confirmed by differential scanning calorimetry. Diacylglycerol is also found to promote a lamellar to "isotropic" (Q(224) cubic) transition in mixtures of phosphatidylcholine: phosphatidylethanolamine:cholesterol. This nonreversible transition is also observed by (31)P nuclear magnetic resonance and detected as a large increase in TMA-DPH steady-state anisotropy. The same technique reveals as well that lysophosphatidylcholine counteracts the effect of diacylglycerol and stabilizes the lamellar phase in both transitions. Diacylglycerol and lysophosphatidylcholine are known to respectively promote and inhibit membrane fusion in a variety of systems. These data are interpreted in support of the hypothesis of a highly bent structural fusion intermediate ("stalk"). They also show the interest of lipid-phase studies in predicting and rationalizing membrane fusion mechanisms.  相似文献   
70.
Clinical records were reviewed to examine the effectiveness of stapedectomy in patients 70 years and older. A total of 154 patients was studied, including 11 with profound hearing loss with long-standing otosclerosis. Ages at the time of surgery ranged from 70 to 92 years (mean, 76.3 years). The mean pure-tone average (500, 1,000, 2,000, and 4,000 Hz) improved 30.6 dB after surgery for the 143 patients in the main otosclerotic group and 26.8 dB for the patients in the profound-hearing-loss group. The rate of successful stapedectomies for the 70(+)-year-old patients (90.9%) and the younger comparison group (90.0%) were similar. These findings extend the documented range of stapedectomy as a safe and effective procedure through the eighth decade of life.  相似文献   
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