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991.
We report a case of an anomalous right coronary artery arising from the morphological left sinus of Valsalva in a patient with Kartagener's syndrome. Literature review has revealed only a small number of cases of anomalous coronary arteries in patients with dextrocardia and none previously reported in Kartagener's syndrome.  相似文献   
992.
The prognostic significance of tumour cell proliferation was investigated in a series of 418 gastric carcinomas using the monoclonal antibody MIB-1. Owing to strong intratumoural heterogeneity of MIB-1 expression three different proliferation indices (PIs) were determined in all carcinomas: (1) PImax in areas of maximal tumour cell proliferation, (2) PIrand in areas randomly distributed over the whole tumour. (3) PIfront in areas exclusively located at the tumour invasion front. There was a strong intertumoral heterogeneity with PImax ranging from 4.9% to 92.2%, PIrand ranging from 3.4% to 81.4% and PIfront ranging from 4.2% to 87.1%. The mean values were 51.3% +/- 19.7 for PImax, 34.2% +/- 18.3 for PIrand and 37.2% +/- 19.5 for PIfront. Whereas no statistically significant correlation could be found between proliferative activity and the clinicopathological parameters depth of invasion, lymph node involvement or grade of tumour differentiation, there was a positive correlation between a high proliferation index at the tumour invasion front (PIfront) and the presence of blood or lymphatic vessel invasion. No significant correlation could be demonstrated between the different proliferation indices and survival, even when different subgroups of patients were analysed separately. The present results suggest that the immunohistochemical evaluation of the proliferation activity has no predictive value for the prognosis of gastric cancer patients or the identification of subgroups of patients who may be at higher risk.  相似文献   
993.
OBJECTIVE: Percutaneous endoscopic gastrostomy (PEG) tube placement is the preferred method for long-term enteral feeding of patients who are unable to take food by mouth. Despite the widespread acceptance of the procedure, no large-scale study of the long-term outcomes of patients receiving PEG tubes has been reported. The objective of this study was to determine the survival of patients in whom PEG tubes are placed. DESIGN: Retrospective cohort study using data obtained from two computerized databases. SETTING: Department of Veterans Affairs hospitals. PATIENTS: Seven thousand three hundred sixty-nine patients who received a PEG tube in fiscal years 1990 through 1992. RESULTS: For the 7,369 patients, the mean age was 68.1 years and 98.6% were men. PEG tubes were most commonly places in patients with cerebrovascular disease (18.9%), other organic neurologic disease (28.6%), or head and neck cancer (15.7%). Although the complication rate of the procedure itself was low (4%), because of the severity of their underlying disease, 1,732 patients (23.5%) died during the hospitalization in which the PEG tube was placed. The median survival of the full cohort was 7.5 months. CONCLUSIONS: This study documents the widespread placement of PEG tubes in severely ill patients, half of whom are in the terminal phase of their illness. Further study is needed to determine whether these patients benefit from PEG tube placement in terms of their quality of life and survival.  相似文献   
994.
995.
Ciliary ganglion (CG) neurons, like other neuronal populations, become dependent on their targets for survival during development. We have previously purified and cloned a secreted ciliary neurotrophic factor that was called growth-promoting activity (GPA). We report here the expression and purification of a highly active form of recombinant GPA, the preparation of GPA-specific polyclonal and monoclonal antibodies, and the use of these antibodies to investigate the cellular location and timing of GPA expression in tissues innervated by CG neurons. Virtually all of the trophic activity in extracts of embryonic eyes could be depleted by GPA-specific antibodies. GPA-like immunoreactivity was found in both targets of the CG: the arterial vasculature of the choroid layer and the ciliary body of the eye. In the choroid layer, GPA was localized to smooth muscle cells surrounding the choroid arteries. Staining in the choroid layer was first detectable at embryonic day (E) 10, or about 2 days after cell death has begun in the ganglion, then increased in intensity through E19. Quantification of trophic activity from whole eye extracts at various ages showed a small increase in activity observed between E9 and E12 and at least a 10-fold increase between E12 and E18. The presence of GPA protein in target cells of CG neurons during the specific developmental period when these neurons undergo cell death is consistent with its proposed function as a target-derived ciliary neurotrophic factor.  相似文献   
996.
NJ Shepherd 《Canadian Metallurgical Quarterly》1996,17(2):118-20, 122 passim; quiz 130
This article is designed to help the general or restorative dentist more accurately predict proper implant placement by using palatal stents for the maxilla and lingual stents for the mandible, as well as parallel pin guides and vacupress stents, which help ensure both precise location and angulation. Because these stents and pin guides are easily used during surgery, the restorative dentist can prescribe with accuracy the exact position where the implants should be placed. To further the predictability of implant placement, especially in the anterior maxilla, an abutment can actually be placed into the pilot hole in the bone and checked with a vacupress stent before making the implant socket.  相似文献   
997.
OBJECTIVES: A high prevalence of GI motility disturbances, including deranged esophageal motility, has previously been reported in patients with eating disorders; altered esophageal and gastric motility have been suggested to play an important role in these disease processes. We sought to confirm this association in an independent patient population. METHODS: We performed esophageal manometry in 12 patients with eating disorders (eight patients with bulimia and four with overlap syndromes, including both anorexia and bulimia features) and 12 sex-matched controls. All subjects completed a symptom questionnaire. Motility testing was performed in the standard fashion using a low compliance water perfusion catheter and computerized digital data capture. Coded tracings were interpreted in a blinded fashion. RESULTS: All 24 studies showed normal motility patterns [95% confidence interval for abnormal esophageal motility in eating disorders patients (0, 0.27)]. Mean lower esophageal sphincter pressure was 24.4 mm Hg in patients and 21.8 in controls; all relaxed normally. Mean esophageal body contraction amplitude 3 cm above the lower esophageal sphincter was 82.6 mm Hg in patients and 84.3 in controls; waveform morphology and progression met normal criteria in all studies. Eight of 12 patients reported dysphagia, odynophagia, or both, compared with 1 of 12 controls; patients demonstrated a pattern of increased overall GI symptomatology compared to controls. CONCLUSIONS: We conclude that disordered esophageal motility is uncommon among stable eating disorder outpatients with bulimic features, and that dysphagia and odynophagia are rarely associated with disordered motility in this group.  相似文献   
998.
Multistate self-electrooptic-effect devices (M-SEEDs) containing several quantum-well diodes in series are discussed. It is shown that a device with N diodes in series with a voltage source and illuminated by N diodes in series with a voltage source and illuminated by N light beams has N stable states corresponding to any one (and only one) of the diodes being highly transmissive. This voltage-biased M-SEED can perform contention resolution in the sense required by analog systems, because the diode illuminated by the weakest beam becomes the highly transmitting one on powering up the system. A current-biased M-SEED with N diodes in series with a current supply can have 2N stable states, corresponding to any combination of diodes in their transmitting or absorbing states. This same device can also function as a binary image thresholder. The M-SEEDs are multistable in multiple beams, in contrast to previous multistable optical devices that have multiple states for one beam. Electrically and optically enabled symmetric SEEDs (S-SEEDs) that comprise a pair of quantum-well p-i-n diodes in series with a transistor or a third diode are also discussed. This device is the equivalent of an electrical tristate device that is used in some bus architectures  相似文献   
999.
Measurements of GaAs-AlGaAs multiple-quantum-well (MQW) reflection modulators grown simultaneously on GaAs and silicon substrates are presented. Comparable electroabsorption is observed, with contrast ratios of about 4:1 for both modulators at 20 V. The absorption spectrum of the GaAs-on-Si quantum well shows a single exciton peak, which leads to certain improvements in modulator performance. This study is very encouraging for the growth of GaAs MQW modulators on silicon integrated circuit chips for off-chip communication  相似文献   
1000.
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