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91.
Savaraj N Xu R Landy H Lai S Sternau L Solomon J Wu C Lampidis T Feun L 《Oncology reports》1997,4(4):857-861
Topoisomerase I (TOP I) and II (TOP II) activities and their corresponding levels were analyzed in 27 primary brain tumors and 32 lung cancers (28 NSCLC, 4 SCLC). The TOP I and II activities in primary brain tumors varied from 500-2,000 units/mg and 100-3,000 units/mg respectively. Their corresponding levels varied from <0.01-3.30 (TOP I) and 0.24-8.30 (TOP II) arbitrary units. In lung cancer, the TOP I and II activities ranged from 1,000-4,000 and 500-4,000 units/mg respectively with their levels ranging from 0.30-61.60 and 0.2-14.2 arbitrary units respectively. These parameters were compared in both tumors using the Wilcoxon rank sums test, the difference were statically significance for all four parameters with a p<0.0001 for TOP I and II activities and TOP I levels and p<0.09 for TOP II levels. Using linear regression analysis, there was no correlation between TOP I and II activities and their corresponding levels in primary brain tumor. However, in lung cancer, the relationship between TOP I activities and levels were linear with r(2)=0.2 and p<0.0094, but not for TOP II activity and their levels. There was no relationship between TOP I and TOP II levels in the same tumor for both types of cancer. The future clinical implication of these findings are discussed. 相似文献
92.
Solomon R 《Health for the millions》1994,2(3):26-27
Notions of racial superiority created population control policies. White men defined overpopulation as the root of development problems (e.g., from poverty to political instability) in developing countries and decided to solve it themselves. This notion was accepted without resistance. Governments decided to persuade or coerce women to have fewer children instead of improving living conditions. Since no basic health care system existed in these countries, decision makers delivered Western contraceptive technologies. Hormonal contraceptives and IUDs were heavily promoted, but inadequate back-up services to treat side effects or monitor use existed. Barrier methods, which prevent sexually transmitted diseases, were not promoted. Pregnancy prevention was more important than safety. Women had no control over their own fertility. Views of Margaret Sanger, a pioneer of the birth control movement, formed the foundation for more aggressive laws based on eugenics. The American Birth Control League advocated racial progress and sterilization. Large organizations initiated contraceptive research. Later public institutions took over contraceptive research that focused on female methods because the field was dominated by males. Developing countries depend on the US Food and Drug Administration (FDA) rulings to develop their own guidelines on contraceptives. The pharmaceutical industry weakens FDA'S resolve. It considers developing countries to be a huge expanding market. The Western attitude that family planning is much safer than childbearing punishes the poor for their poverty and disregards long-term risks to women. Providers do not always inform women about risks of contraceptives. The sterilization program in India was based on restricted choice, coercion, targets, and incentives. Success stories include Cuba, South Korea, Sri Lanka, and Kerala State in India. Expansion of basic health care and improvement of the general condition of people's lives are needed. 相似文献
93.
94.
The Working Alliance Inventory was used to measure the strength of the therapeutic relationship between seriously mentally disabled case management clients and their case managers in a randomized trial of consumer-provided case management services. It was found that while there was no difference in the strength of the alliance between the consumer and nonconsumer teams of case managers, there were positive relationships between alliance and some outcomes, including quality of life, symptomatology, attitudes toward medication compliance, and satisfaction with mental health treatment. 相似文献
95.
This article reports the results of a randomized trial of a team of case managers who are mental health consumers compared to a team of nonconsumer. Using a repeated measures MANOVA design, consumer case managers were found to be as effective as a team of nonconsumer case managers in maintaining the stability of severely mentally disabled clients served over a 2-year period. Implications for the employment of consumers in mental health services and the vocational capacity of persons with mental illness are discussed. 相似文献
96.
Dephosphorylation of cyclin-dependent kinases by type 2C protein phosphatases 总被引:9,自引:0,他引:9
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Activating phosphorylation of cyclin-dependent protein kinases (CDKs) is necessary for their kinase activity and cell cycle progression. This phosphorylation is carried out by the Cdk-activating kinase (CAK); in contrast, little is known about the corresponding protein phosphatase. We show that type 2C protein phosphatases (PP2Cs) are responsible for this dephosphorylation of Cdc28p, the major budding yeast CDK. Two yeast PP2Cs, Ptc2p and Ptc3p, display Cdc28p phosphatase activity in vitro and in vivo, and account for approximately 90% of Cdc28p phosphatase activity in yeast extracts. Overexpression of PTC2 or PTC3 results in synthetic lethality in strains temperature-sensitive for yeast CAK1, and disruptions of PTC2 and PTC3 suppress the growth defect of a cak1 mutant. Furthermore, PP2C-like enzymes are the predominant phosphatases toward human Cdk2 in HeLa cell extracts, indicating that the substrate specificity of PP2Cs toward CDKs is evolutionarily conserved. 相似文献
97.
PURPOSE: The majority of graduating medical students will become primary care physicians. We discuss what urological topics primary care physicians need to know, proficiency in urological skills of primary care physicians and undergraduate urological curriculum recommendations that would serve the needs of primary care physicians. MATERIALS AND METHODS: A written survey instrument was mailed to all 452 family practice residency directors in the United States. Subjects rated how well family practice physicians need to know urological topics and how proficient they must be in urological skills. RESULTS: A total of 329 responses were received (response rate 73%). Respondents indicated that they need to know urinary tract infection, sexually transmitted disease, epididymitis, benign prostatic hyperplasia diagnosis, hematuria and erectile dysfunction diagnosis very well. They indicated a greater need to know diagnostics than staging or management of prostate, bladder, renal or testis cancer (p <0.05). Among diagnostics respondents indicated that generalists should be highly proficient in urinalysis interpretation. Proficiency was ranked greater for interpretations of semen analysis than excretory urogram, abdominal computerized tomography or magnetic resonance imaging, or renal ultrasound (p <0.05). Proficiency in catheter insertion and circumcision was ranked highly, and vasectomy was ranked moderately. CONCLUSIONS: Primary care physicians need to know and be proficient in many urological topics and skills. They need to know diagnostics better than staging and management information, and urological infectious topics better than urological cancers. They need to be proficient in physical examination, urinalysis interpretation, catheter insertion, circumcision and vasectomy. Undergraduate medical education should reflect these needs. 相似文献
98.
Identification of a pathogenicity island required for Salmonella survival in host cells. 总被引:13,自引:0,他引:13
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H Ochman F C Soncini F Solomon E A Groisman 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(15):7800-7804
We have identified a region unique to the Salmonella typhimurium chromosome that is essential for virulence in mice. This region harbors at least three genes: two (spiA and spiB) encode products that are similar to proteins found in type III secretion systems, and a third (spiR) encodes a putative regulator. A strain with a mutation in spiA was unable to survive within macrophages but displayed wild-type levels of epithelial cell invasion. The culture supernatants of the spi mutants lacked a modified form of flagellin, which was present in the supernatant of the wild-type strain. This suggests that the Spi secretory apparatus exports a protease, or a protein that can alter the activity of a secreted protease. The "pathogenicity island" harboring the spi genes may encode the virulence determinants that set Salmonella apart from other enteric pathogens. 相似文献
99.
Fernandez AP Aronson S Toledano A Winkelmann J Saldivar J Feinstein SB 《Echocardiography (Mount Kisco, N.Y.)》1996,13(5):489-498
Videodensitometric analysis of myocardial contrast echocardiography is traditionally performed off line. Recently, an online contrast ultrasound analysis system, Acoustic Densitometry (Hewlett-Packard), was introduced. We compared pixel intensities acquired with Acoustic Densitometry to pixel intensities derived from videodensitometry. A tissue phantom was imaged in phase I using three transducer frequencies (2.5, 3.5, and 5.0 MHz). In phase II, an in vitro flowing tube model with various concentrations of Albunex® was imaged at two flow rates, 0.6 and 1.2 m/sec, and at two transducer frequencies, 2.5 and 3.5 MHz. The relationship between pixel intensities yielded by the two systems for identical ultrasound signals was determined with linear regression. Intensities derived with Acoustic Densitometry strongly correlated with those derived from the offline videodensitometry system. The intensities were related by a predictive multiplicative factor based on display characteristics of the two systems. These results suggest that semiquantitative, online perfusion analysis with Acoustic Densitometry is as sensitive as analysis offline with videodensitometry. 相似文献
100.