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81.
82.
We describe a 40-Gbit/s-class clock and data recovery (CDR) circuit with an extremely wide pull-in range. A Darlington-type voltage-controlled oscillator (VCO) is newly designed to cover the STM-256/OC-768 full-rate-clock frequencies with a wide frequency margin. We also describe a new lock detector using an exclusive-NOR gate. The CDR IC was fabricated using InP/InGaAs HBTs. Error-free operation and wide eye opening were confirmed for 40-, 43-, and 45-Gbit/s PRBS with a word length of 2/sup 31/ - 1. We attached a frequency search and phase control (FSPC) circuit to the chip as a new frequency acquisition aid, and this allows the CDR circuit to pull in throughout a 39-45-Gbit/s range. The peak-to-peak and rms jitter of the recovered clock were 3.6 and 0.48 ps, respectively.  相似文献   
83.
Achromobacter xylosoxidans is a gram-negative bacterium whose natural habitat has not been clearly defined. It has been isolated from ear discharge and the large intestine of humans and from various hospital or environmental water sources. Infection with A. xylosoxidans in humans has been documented, and resulting illnesses include meningitis, pneumonia, cholecystitis, peritonitis and urinary tract infection. Bacteremia due to A. xylosoxidans is rare, and little information on treatment is available. Two cases of bacteremia due to A. xylosoxidans in patients with hemapoietic malignancies are reported herein. Case 1 involved a 70-yr. male whose clinical diagnosis was IgA lambda-type plasmacytoma. Case 2 involved 72-yr. male whose clinical diagnosis was acute lymphatic leukemia (L2). Both patients had been catheterized. Neutropenia was noted and the white blood cell counts were 20/microliter in case 1 and 35/microliter in case 2 when A. xylosoxidans was isolated from the blood culture. We suggest that bacteremia due to A. xylosoxidans may have been related to the presence of the catheter and neutropenia.  相似文献   
84.
We present the spatial structure of binase, a small extracellular ribonuclease, derived from 1H-NMR* data in aqueous solution. The total of 20 structures were obtained via torsion angle dynamics using DYANA program with experimental NOE and hydrogen bond distance constraints and phi and chi1 dihedral angle constraints. The final structures were energy minimised with ECEPP/2 potential in FANTOM program. Binase consists of three alpha-helices in N-terminal part (residues 6-16, 26-32 and 41-44), five-stranded antiparallel beta-sheet in C-terminal part (residues 51-55, 70-75, 86-90, 94-99 and 104-108) and two-stranded parallel beta-sheet (residues 22-24 and 49-51). Three loops (residues 36-39, 56-67 and 76-83), which play significant role in biological functioning of binase, are flexible in solution. The differences between binase and barnase spatial structures in solution explain the differences in thermostability of binase, barnase and their hybrids.  相似文献   
85.
An extractionless method for determining aflatoxin M1 (AFM1), a major metabolite of aflatoxin B1 (AFB1), in human urine was developed. The biological fluid is injected directly into the chromatographic system after simple dilution and centrifugation. A pre-column, packed with a cation-exchange phase and coupled on-line to a column-switching liquid chromatography (LC) system, is used for sample pre-treatment and concentration. The analytes are non-selectively desorbed with the LC eluent and cleaned by means of a column-switching procedure. Pre-treatment and analysis were performed within 40 min. Average AFMI recovery reached 97% in the 10-100 ng/l range of urine. The detection limit of AFM1 in urine and milk was 2.5 ng/l for 1 ml of injected sample. A comparison with an immunoaffinity column clean-up and LC method was performed. The method was applied to determine AFM1 in the urine of AFB1 gavaged rats, and in the urine of both potentially exposed and supposedly unexposed workers. The method was also extended to milk.  相似文献   
86.
Hormone-sensitive lipase (HSL) catalyzes the rate-limiting step in adipocyte lipolysis. We have studied the effect of glucose and long chain fatty acids on the HSL mRNA content of 3T3-F442A adipocytes. Exposure of the cells for 32 h to a medium without glucose led to a decrease by a factor of 2.5-3 in the HSL mRNA without a change in C/EBP alpha mRNA or triglyceride content of the adipocytes. The reduction in HSL mRNA level was accompanied by a decrease in HSL total activity. The effect of glucose exposure was observed after 24 h of exposure and was reversible. Treatment of the adipocytes with oleate did not affect HSL expression. These data show that glucose modulates HSL gene expression and hence could participate in the regulation of adipose tissue lipolysis.  相似文献   
87.
We describe a 60-year-old woman with leg pain. Although metastatic bone tumor and atypical cells mimicking signet-ring cells in the bone marrow picture were observed, systemic survey revealed no primary lesion. The patient died two months after admission from systemic progress of the disease. Autopsy revealed a small focus of adenocarcinoma within the right upper lobe of the lung and systemic metastases without any particular changes in the gastrointestinal tract. The tumor cells of the lung were diffusely positive for cytokeratin 7, whereas cytokeratin 20 immunoreactivity was weak and focal, and that supported the lung origin of the present tumor. Moreover, the tumor cells in the bone marrow showed a similar pattern in immunoreactivity. These findings suggest that cytokeratin 7 and cytokeratin 20 immunoreactivity is helpful for the premortem diagnosis of the metastatic tumor of unknown origin.  相似文献   
88.
89.
In a previous study, we found that oral chromium nicotinate overcame sucrose-induced hypertension in spontaneously hypertensive rats (SHR). Accordingly, we examined more chromium compounds to determine if others were more or less effective in regulating blood pressure (BP) of SHR. Since chromium is postulated to be an antioxidant, we also assessed the ability of different chromium compounds to alter free radical formation measured by determining thiobarbituric acid reactive substances (TBARS). The control group of SHR ingested a diet low in chromium, and 5 other groups ate the same diet with various chromium compounds added at 5 ppm-chloride, acetate, nicotinic acid-glycine-cysteine-glutamic acid (NA-AA), picolinate, and nicotinate. Following this, the rats were challenged with drinking water containing 5% and 10% w/v sucrose. Except for NA-AA, all chromium compounds inhibited the sucrose-induced elevation of systolic BP; and acetate, picolinate, and nicotinate chromium compounds lowered HbAIC below control. Only chromium acetate and nicotinate significantly lowered both hepatic and renal TBARS. Chromium picolinate lowered hepatic TBARS, and chromium chloride and NA-AA lowered neither. We conclude that chromium, rather than a specific ligand, plays a major role in ameliorating sucrose-induced BP elevations and can act as an antioxidant.  相似文献   
90.
Based on the present state of the art of the separation technology, recycling of fission-product rare elements (FRE) in the FBR spent fuel is discussed. The rad.-waste fractionation is in accordance with the present society's trend toward zero-emission, and the mean of salt-free method utilizing electrochemistry agrees with the principles of the newly established green chemistry. A catalytic electrolytic extraction method is proposed to separate the target, radioactive but potentially strategic elements, Pd, Ru, Rh, Re (Tc), Te and Se dissolved in the HLLW. It avoids secondary waste arising. This method is particularly feasible for the separation of Pd where cyclic reaction of metal cations such as Pd(II) or Fe(II), acting as promoters or mediators and already contained in HLLW, accelerates the electrochemical deposition of Ru, Rh and Re. Elemental separation not only offers alternative material resources to meet expanding demands for catalysts in Fuel Cell/Soft Energy system but is also the first step for transmutation or other selective strategies for waste management of long-lived fission products (LLFP).  相似文献   
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