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101.
A 4-Mb high-speed DRAM (HSDRAM) has been developed and fabricated by using 0.7-μm Leff CMOS technology with PMOS arrays inside n-type wells and p-type substrate plate trench cells. The 13.18-mm×6.38-mm chip, organized as either 512 K word×8 b or 1 M word×4 b, achieves a nominal random-access time of 14 ns and a nominal column-access time of 7 ns, with a 3.6-V Vcc and provision of address multiplexing. The high level of performance is achieved by using a short-signal-path architecture with center bonding pads and a pulsed sensing scheme with a limited bit-line swing. A fast word-line boosting scheme and a two-stage word-line delay monitor provide fast word-line transition and detection. A new data output circuit, which interfaces a 3.6-V Vcc to a 5-V bus with an NMOS-only driver, also contributes to the fast access speed by means of a preconditioning scheme and boosting scheme. Limiting the bit-line voltage swing for bit-line sensing results in a low power dissipation of 300 mW for a 60-ns cycle time  相似文献   
102.
OBJECTIVE: To investigate the prevalence of coronary artery disease (CAD), atherothrombotic brain infarction (ABI), and peripheral arterial disease (PAD) in older Hispanics and the association with risk factors in this population. DESIGN: A retrospective analysis of charts from all Hispanics seen during January 1996 through July 1997 at an academic hospital-based geriatrics practice. SETTING: An academic, hospital-based, primary care geriatrics practice staffed by fellows in a geriatrics training program and by full-time faculty geriatricians. PATIENTS: One hundred sixty women and 53 men, mean age 80 +/- 8 years (range 64 to 100), were included in the study. MEASUREMENTS AND MAIN RESULTS: Of 213 Hispanics in the study, 59 (28%) had documented CAD, 43 (20%) had ABI, 34 (16%) had PAD, and 90 (42%) had either CAD, ABI, or PAD. Serum total cholesterol and triglycerides were measured in 202 of 213 subjects (95%). Serum high-density lipoprotein cholesterol was measured in 137 of 213 patients (64%). Other risk factor data were documented in all patients. Multiple logistic regression analysis performed in 202 patients using the variables age, gender, cigarette smoking, hypertension, diabetes mellitus, obesity, serum total cholesterol, and serum triglycerides showed statistically significant associations between prevalent CAD, ABI, or PAD and age (P = .002, odds ratio (OR) = 1.083), cigarette smoking (P = .002, (OR) = 3.865), hypertension (P = .007, (OR) = 2.749), diabetes mellitus (P = .028, (OR) = 2.386), obesity (P = .014, (OR) = 2.608), serum total cholesterol (P < 0.001, (OR) = 1.025), and serum triglycerides (P = .017, (OR) = .993). CONCLUSIONS: Either CAD, ABI, or PAD was present in 42% of 213 older Hispanics. There were statistically significant associations between prevalent CAD, ABI, or PAD in older Hispanics and risk factors, including age, cigarette smoking, hypertension, diabetes mellitus, obesity, and serum total cholesterol.  相似文献   
103.
104.
A network-theoretic approach to the design of a dynamic precompensator C(s) for a multiinput, multioutput plant T(s) is considered. The design is based on the relative degree of each element of T(s). Specifically, an efficient algorithm is presented for determining whether a given plant T(s) has a diagonal precompensator C( s) such that, for almost all cases, T(s)C (s) has a diagonal interactor. The algorithm also finds any optimal precompensator, in the sense that the total relative degree is minimal. The algorithm can be easily modified to work even when a T(s) represented by a nonsquare matrix is given  相似文献   
105.
Intracytoplasmic sperm injection (ICSI) and partial zona dissection followed by insemination (PZD-I) were used to establish a microinjection system in cynomolgus monkeys (Macaca fascicularis), which are potential models for human reproduction. Two experimental systems were studied, in which either hamster oocytes or cynomolgus monkey oocytes were used as the vehicle. When hamster oocytes were used, 66 out of 81 ICSI-treated oocytes (82%) showed sperm head swelling or pronucleus formation. Following PZD-I of hamster oocytes the rates of spermatozoa penetration (85/114; 75%) and fertilization (71/114; 62%) were relatively high. When cynomolgus monkey oocytes were used, 19 out of 31 (61%) were fertilized by ICSI with cynomolgus monkey spermatozoa and, subsequently, two embryos (7%) developed to the morula stage. In total, 94% (15/16) of the PZD-I treated oocytes were penetrated by spermatozoa and 63% (10/16) were fertilized. These results demonstrate that both micromanipulation techniques can be used in assisted fertilization with cynomolgus monkeys.  相似文献   
106.
BACKGROUND: To assess the role of contrast enemas for the evaluation of leaks in symptomatic and asymptomatic patients after the first stage of restorative proctocolectomy. METHODS: We reviewed the findings of 59 contrast enemas in 40 patients who underwent total proctocolectomy with creation of an ileoanal pouch and a proximal diverting ileostomy. Thirty-seven patients initially underwent routine contrast studies of the ileoanal pouch, and three underwent contrast studies because of suspected fistulas or obstruction. Medical records were also reviewed to determine the clinical presentation and course of these patients. RESULTS: Of 37 patients who underwent routine postoperative contrast enemas, 33 (89%) had normal studies, three (8%) had clinically silent leaks (including two blind-ending tracks from the ileoanal anastomosis and one from the pouch), and one (3%) had pouchitis. In all three patients with unsuspected leaks, ileostomy closure was delayed. In two other patients with abdominal pain and fever, contrast enemas revealed leaks from the ileoanal pouch and distal ileum, respectively. The remaining patient had a contrast enema because of abdominal pain and distention; this patient had a distal ileal obstruction due to adhesions. CONCLUSIONS: Routine postoperative contrast studies revealed clinically silent leaks from the ileal J pouch or ileoanal anastomosis in three of 37 patients (8%) after the first stage of restorative proctocolectomy. Our findings suggest that routine contrast enema can detect clinically silent leaks after this surgery.  相似文献   
107.
Recent preventive maintenance for equipment has grown to include diagnosis of the insulation of cables under hot-line conduction. Much of the equipment constructed during the high-growth period in the 1960s has become obsolete. Recent circumstances make it difficult to obtain a longer service interruption time. Results of a study of the method that measures the live-wire insulation resistance by superimposing dc 50 V to a high-voltage busbar through GPT and forms a bridge with the resistance of a cable insulation are discussed. It is clarified that this live-wire insulation diagnostic method is highly effective at detecting degradation of a cable insulation resistance and is, therefore, suitable for so-called trend monitoring as well.  相似文献   
108.
The contents and compositions of the 1-O-alk-1′-enyl-2-acyl, 1-O-alkyl-2-acyl, and 1,2-diacyl glycerophospholipids in the muscle and viscera of the ascidianHalocynthia roretzi, and of the gonad of the sea urchinStrongylocentrotus intermedius, which are eaten to some extent in Alaska and in Asia, were analyzed by gas-liquid chromatography. 1-O-Alk-1′-enyl-2-acyl glycerophospholipids were found in all of the samples, accounting for 64.4–69.0% of the ethanolamine glycerophospholipid (EPL). By contrast, the levels of the 1-O-Alk-1′-enyl-2-acyl choline glycerophospholipids (CPL) were low (3.1–5.7%). CPL was rich in the 1-O-alkyl-2-acyl subclass amounting to 12.5–23.9% in the ascidian sample. The level of CPL in the sea urchin gonad was extremely high, amounting to 46.1%. The most prominent alkyl chains in thesn-1 position of CPL from the ascidian muscle were 16∶0 (44.6%), 18∶1 (26.5%), and 18∶0 (10.7%), and of CPL from the sea urchin gonad were 18∶0 (36.2%), 16∶0 (33.0%), and 18∶1 (17.8%). Unusually high levels of odd-numbered alkyl chains, e.g., 19∶0 andanteiso 17∶0, were detected in the CPL of all samples. The prominent alkenyl chains of EPL were 18∶0 (69.4%), 16∶0 (10.0%), and 18∶1 (8.54%) (not counting the vinyl double bond) for the sea urchin gonad. Relatively high levels of 20∶1 alkenyl chains were also present. The glycerolsn-2 positions contained high proportions of polyunsaturated fatty acids. Thus, 20∶5n-3 (43.6%) and 22∶6n-3 (20.1%) were most abundant in the alkylacyl CPL from the ascidian muscle and 20∶5n-3 (54.9%) and 20∶4n-6 (30.1%) in alkylacyl CPL from the sea urchin gonad. Despite a possible interconversion of the alkyl and alkenyl chains of each class of the ether phospholipids, they showed few features in common.  相似文献   
109.
Single-flux quantum logic (SFQ) circuits, in which a flux quantum is used as an information carrier, have the possibility for opening the door to a new digital system operated at over 100-GHz clock frequency at extremely low power dissipation. The SFQ logic system is a so-called pulse logic, which is completely different from the level logic for semiconductors like CMOS, so circuit design technologies for SFQ logic circuits have to be newly developed. Recently, much progress in basic technologies for designing SFQ circuits and operating circuits at high speeds has been made. With advances in these design tools, large-scale circuits including more than several thousand junctions can be easily operated with the clock frequency of more than several tens of gigahertz. High-end routers and high-end computers are possible applications of SFQ logic circuits because of their high throughput nature and the low power dissipation of SFQ logic. In this paper, recent advances of SFQ circuit design technologies and recent developments of switches for high-end routers and microprocessors for high-end computers that are considered possible applications for SFQ logic will be described.  相似文献   
110.
We report a 42-year-old left-handed woman with congenital right hemiparesis and bilateral mirror movements in the hands. She had a porencephaly of the left hemisphere and the brain MRI demonstrated cortical and subcortical defect of the left hemisphere from Brodmann's area 6 to 40 including the left motor cortex. By electrical stimulation of the left median nerve at the wrist, N20 of the somatosensory evoked potential was recorded in the right postcentral gyrus by using the dipole tracing method. Long-loop reflexes from the bilateral thenar muscles were recorded and their latencies were almost the same. The stimulation of the right median nerve did not evoke N20, nor long-loop reflex. These electrophysiological findings suggest that the reorganization of the motor system made the right motor cortex to innervate bilateral hands, and caused bilateral mirror movements. In other words, the mirror movements managed to relieve the paralysis of the right hand though the damage of the left motor cortex was present. In the previous literature we are able to find hypotheses regarding the mechanism of mirror movements in congenital hemiparesis. Here we discussed about the reorganization of the motor system in the damaged brain.  相似文献   
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