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We measured the concentrations of MCNU and CBDCA in the serum, brain tumor and normal brain tissue. Six patients with malignant glioma were treated with intravenous chemotherapy using 80mg/m2 MCNU and 300mg/m2 CBDCA during surgery. After drug administration, specimens of serum, tumor and normal brain tissue were collected every 30 min and then the drug concentration in each sample was measured. The highest MCNU levels in all samples were obtained immediately after administration which followed by gradual decrease. On the contrary, the mean CBDCA levels in the tumor and normal tissue remained almost at a constant level, although serum CBDCA level declined rapidly as MCNU. As expected, MCNU seemed to have advantages in the treatment of brain tumors as it distributed with higher concentration in the tumor tissue than in the serum and normal brain tissue. On the contrary, CBDCA in the tumor tissue did not exceed the concentration in the serum. Nevertheless, it remained longer in the tumor tissue with a constant level, suggesting that CBDCA can achieve an effective area under the concentration versus time curve (AUC) in the brain tumor tissue to kill tumor cells.  相似文献   
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A new architecture for serial access memory is described that enables a static random access memory (SRAM) to operate in a serial access mode. The design target is to access all memory address serially from any starting address with an access time of less than 10 ns. This can be done by all initializing procedure and three new circuit techniques. The initializing procedure is introduced to start the serial operation at an arbitrary memory address. Three circuit techniques eliminate extra delay time caused by an internal addressing of column lines, sense amplifiers, word lines, and memory cell blocks. This architecture was successfully implemented in a 4-Mb CMOS SRAM using a 0.6 μm CMOS process technology. The measured serial access time was 8 ns at a single power supply voltage of 3.3 V  相似文献   
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BACKGROUND: High immigration rates contribute to the high incidence of pediatric tuberculosis (TB) in San Diego, Calif. Adolescents frequently have poor access to health care and may not receive appropriate TB screening. School-based screening has been ineffective in detecting TB in other parts of the country. OBJECTIVE: To determine the prevalence of TB infection and disease in a high-risk population of high school students through school-based screening. DESIGN AND PARTICIPANTS: Cross-sectional study of TB prevalence and an analysis of risk factors for TB infection in students attending 2 San Diego high schools with high percentages of non-US-born students. MAIN OUTCOME MEASURES: Positive induration (> or =10 mm) with Mantoux tuberculin skin test. A chest radiograph or clinical findings consistent with active TB. RESULTS: A total of 744 (36%) students at high school 1 and 860 (57%) students at high school 2 participated. Ninety-five (12.8%) and 207 (24.1%) students, respectively, had positive tuberculin skin test results. One student had a chest radiograph that showed active TB. Smear for acid-fast bacteria and culture for Mycobacterium tuberculosis had negative results. Vietnamese, Filipino, and Latino ethnic groups were significantly more likely to have positive tuberculin skin test results than the white population (P<.05). Non-US-born students were significantly more likely to have positive tuberculin skin test results than US-born students in all ethnic groups except the Latino group. CONCLUSION: Although treatment of TB coupled with aggressive public health investigation is the most cost-beneficial way of preventing TB, targeted school-based screening may be an effective way of detecting TB infection in high-risk populations with poor access to health care.  相似文献   
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There is strong evidence that depression can have profound negative effects on the functional status, psychologic outlook, and possibly the medical outcome of cancer patients. Its presence often is taken for granted by both patients and physicians as being either inevitable or easily explained by the grim prognosis and complex treatment regimens experienced by many cancer patients, and thereby less deserving of an aggressive approach to diagnosis and treatment. This view is inappropriate, and hinders an effective approach to the problem. Effective treatment, similar to that provided for any other depressed patient, can enhance the cancer patient's overall approach to life and the disease, irrespective of the eventual medical outcome.  相似文献   
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A method for cause and effect analysis of chemical processing systems has been developed on the concept of a signed directed graph. The signed directed graph, called a “model graph,” is used for representing cause and effect relationships among process variables in a system, and a “Pattern” on the graph is introduced to represent a state of the system, which is specified by “0” for normal state, “ + ” and “ ? ” for larger and smaller deviation from the normal state, respectively. For a given model graph and pattern on it, the cause of state changes and the manner of their propagation are easily found out by the present approach, which is mainly based on the depth-first search algorithm developed by Tarjan. As an illustrative example, a propane vaporizer has been taken to show the usefulness of the present approach.  相似文献   
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The characteristics and metabolism of lipoproteins were reviewed. Apolipoproteins has been studied in the fields of neurological diseases as well as hyperlipidemia. A highly significant association between apolipoprotein E (ApoE) epsilone 4 allele and late-onset familial and sporadic Alzheimer's disease (AD) was reported. The recent studies also described the following: (1) late-onset familial AD linked to the proximal long arm of chromosome 19; (2) the presence in the CSF of several proteins, one of which was ApoE, what bound to immobilized amyloid beta-peptide (beta A4) with high avidity; and (3) staining by antisera to ApoE of senile plaques, neurofibrillary tangles, and cerebral vessel amyloid deposits in AD brains. Furthermore, (4) both purified ApoE isomers, ApoE3 and ApoE4, bound to beta A4 synthetic peptide, forming a complex that resisted dissociation by boiling in sodium dodecyl sulfate, but the isomers showed different kinetics in doing so: binding by ApoE4 was observed in minutes, while binding by ApoE3 required hours; and (5) ApoE4 did not bind to beta A4 peptide at pH less than 6.6, while ApoE3 bound to beta A4 peptide from pH7.6 to 4.6. We studied ApoE phenotype expression and the corresponding allele frequencies (epsilon 2, epsilon 3 and epsilon 4) in Japanese patients with late-onset sporadic AD. The frequency of the ApoE epsilon 4 allele was obviously high in AD patients compared with the controls, but it was not different between vascular dementia patients and the controls. These results suggest that ApoE isoforms may play a functional role in the pathophysiology of late-onset familial and sporadic AD and that the isoform-specific difference in beta A4 binding may be involved in forming the AD lesion.  相似文献   
39.
A simple high-performance liquid chromatographic (h.p.l.c.) method has been developed for determining total malondialdehyde (MDA), including free MDA and MDA released from its precursor in vegetable oils. Free MDA was reacted with dansyl hydrazine in an acidic medium, and the product, 1-dansyl-pyrazole(DP), was determined by h.p.l.c. The reaction releasing MDA from its precursor requires Fe3+ in 5% hydrochloric acid medium. Recoveries of free MDA and tetramethoxypropane (used as an MDA precursor) in vegetable oils were satisfactory. During autoxidation, a remarkable difference between the DP values of methyl oleate, methyl linoleate and some vegetable oils, and that of methyl linolenate was observed. Only methyl linolenate released MDA during autoxidation. For autoxidised methyl linolenate the DP value correlated with the thiobarbituric acid(TBA) value, although the DP value was only 30% of the TBA value.  相似文献   
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