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191.
192.
The clinical and cytogenetic data of the first patient proven to belong to the fifth Fanconi anemia complementation group are described. The Turkish boy presented with psychomotoric retardation, growth retardation, retarded bone age, brachycephaly, hypotelorism, epicanthus, syndactyly, brachydactyly, renal dystopia, and cryptorchism. In addition, an asymmetrical skeletal anomaly was seen with a double distal phalanx of the left thumb and hypoplasia of the right thumb. Typical hematological features of the disorder developed, at the age of 2.5 years, about 1 year after diagnosis. Cytogenetic studies confirmed the clinical diagnosis and revealed a spontaneous chromosomal instability and hypersensitivity to the cross-linking agents diepoxybutane and Trenimon. The findings in the patient, who is considered to be the standard for the fifth Fanconi anemia complementation group, are compared with data reported for other patients affected with Fanconi anemia.  相似文献   
193.
Spherical dosage forms have been reported to be an efficient and effective method for delivering drugs into the body and controlling their dissolution rate. Substantial work has been conducted in these laboratories illustrating the advantages of microcrystalline cellulose-based spheres for these purposes. Through various methodologies, but most routinely the extrusion and marumerization technique, it has been determined by Funck, et al. that not more than 50% drug can be incorporated into a sphere formulation without the addition of other binders.

Because of the nature of the extrusion and marumerization manufacturing process, the type of drug being processed and the resultant particle size requirements of the spheres, the percent of spheres falling outside the desired particle size can range from between 3% and 20%. For this reason and the possibility of operator errors, our objective was to determine the parameters which needed monitoring when reprocessing was necessary.  相似文献   
194.
It is appealing to contemplate how VLSI or wafer-scale integrated systems incorporating free-space optical interconnection might outperform purely electrically interconnected systems. This paper first provides a uniform treatment of a general class of optical interconnects based on a Fourier-plane imaging system with an array of sources in the object plane and an array of receptors in the image plane. Sources correspond to data outputs of processing “cells,” and receptors to their data inputs. A general abstract optical imaging model, capable of representing a large class of real systems, is analyzed to yield constructive upper bounds on system volume that are comparable to those arising from “3-D VLSI” computational models. These bounds, coupled with technologically derived constraints, form the heart of a design methodology for optoelectronic systems that uses electronic and optical elements each to their greatest advantage, and exploits the available spatial volume and power in the most efficient way. Many of these concepts are embodied in a demonstration project that seeks to implement a bit-serial, multiprocessing system with a radix-2 butterfly topology, and incorporates various new technology developments  相似文献   
195.
Two cases with osteolytic bone metastases from cervical cancer and esophageal cancer treated by local therapy were reported. The first case is a 53-year-old female with bone metastases of left ischium developed 1 year after hysterectomy. She was treated by intratumor injection of sizofiran (SPG) 20 mg/w and radiation therapy. After 4 weeks, ischias pain decreased and bone lesion showed remarkable calcification (PR) 8th months later. The second case is a 58-year-old male with bone metastases of the left tibia and fibula developed 1 year after surgery. He was treated by intratumor injection of SPG 20 mg/w x 4 and OK-432 1.0 KE/w x 8 after radiation therapy. After 4 weeks, pain and swelling of left leg decreased and bone lesions showed remarkable calcification (PR) three months later. We suggest that intratumor injection of SPG and OK-432 with radiation therapy was effective for osteolytic bone metastases.  相似文献   
196.
197.
Functional magnetic resonance imaging (fMRI) is capable of detecting task-induced blood oxygenation changes using susceptibility sensitive pulse sequences such as gradient-recalled echo-planar imaging (EPI). The local signal increases seen in the time course are believed to be due to an increase in oxygen delivery that is incommensurate with oxygen demands. To help isolate the sources of functional signal changes, the authors have incorporated various forms of diffusion weighting into EPI pulse sequences to characterize the apparent mobility of the functionally modulated protons. Results suggest that the majority of the functional signal at 1.5 T arises from protons that have apparent diffusion coefficients that are approximately four or five times higher than that of brain tissue. This implies that significant functional signal sources are either protons within the vascular space or protons from the perivascular space that is occupied by cerebrospinal fluid.  相似文献   
198.
Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 71–86, May–June, 1995.  相似文献   
199.
A 6H-SiC thyristor has been fabricated and characterized. A forward breakover voltage close to 100 V and a pulse switched current density of 5200 A/cm2 have been demonstrated. The thyristor is shown to operate under pulse gate triggering for turn-on and turn-off, with a rise time of 43 ns and a fall time of less than 100 ns. The forward breakover voltage is found to decrease by only 4% when the operating temperature is increased from room temperature to 300°C. It is found that anode ohmic contact resistance dominates the device forward drop at high current densities  相似文献   
200.
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