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51.
The absolute granulocyte count (AGC) in 125 blood samples from patients with total white blood cell counts of less than 1,000/microliter was estimated using three different methods, which were then compared for efficiency and accuracy. The three methods were 25 cell differential counts using Wright's-stained blood smears, granulocyte percentage estimates from WBC counting chambers, and combined narrow- and wide-angle light-scatter characteristics determined on a flow cytometer. A survey of clinical laboratories at University Hospital Cancer Centers revealed that the smear differential was the most-often-used method in those laboratories even when less than 25 cells could be counted. Consequently the data obtained from the counting chamber and flow cytometer methods were compared to the smear differential "standard" using linear regression, and outliers were identified. There was good correlation between AGC determined by smear differential and WBC counting chamber (correlation coefficient .911) and excellent correlation between the AGC determined by smear differential and the flow cytometer method (correlation coefficient .970). The flow cytometer method used in this investigation required minimal specimen preparation, and test results were available at a rate of 60 seconds/sample. The ease of sample preparation, speed, and statistical reliability of test results makes the flow cytometer an attractive alternate method of determining granulocyte counts on leukopenic patients as compared to the stained blood smear differential. 相似文献
52.
A frontal lobe neoplasm in a 25-year-old Caucasian man showed the typical histological pattern of a "polar spongioblastoma." Immunoperoxidase staining for glial fibrillary acidic protein (GFAP) was negative while silver stains in paraffin-embedded tissue, and electron microscopy displayed neoplastic cells with neuritic processes. Ultrastructurally there were microtubules, synapses and dense-core neurosecretory granules, all features of a neuroblastic neoplasm. It is suggested that this new growth with its polar spongioblastic appearance is, in fact, a moderately malignant primary cerebral neuroblastoma. 相似文献
53.
Flicker Sharon M. Vaughan Michelle D. Meyers Lawrence S. 《Archives of sexual behavior》2021,50(4):1569-1585
Archives of Sexual Behavior - Compersion is a well-known term in polyamorous communities that connotes the positive emotion an individual may experience in relation to their partner’s... 相似文献
54.
Kiaris H Jones A Spandidos D Vaughan E Field J 《International journal of oncology》1994,5(6):1243-1248
LOH studies provide evidence for the implication of novel TSGs in human tumours. The p arm of chromosome 8 has been reported to harbour tumour suppressor genes (TSGs) which are very likely to be involved in the development of colon, lung, bladder and hepatocellular carcinomas. In addition, the c-myc proto-oncogene which is located on the 8q arm, has been found to be overexpressed in SCCHN. In the present study we have investigated the incidence of loss of heterozygosity (LOH) in chromosome 8 in 37 tumour specimens of squamous cell carcinomas of the head and neck (SCCHN), using a bank of 11 polymorphic microsatellite markers. The aim of this work was to assess whether there was an 8p TSG(s) in SCCHN, as reported in other tumours and also to investigate whether other areas of chromosome 8 exhibit a high LOH. A relatively high incidence of LOH was found for the markers D8S87 (29%) on 8p12 and ANK1 (20%) on 8p21.2-p11. These two markers are located in the area in which TSG(s) for other cancers have been previously described. When the data on D8S87 and ANK1 were analyzed together it was found that 13/35 (37%) of the SCCHN specimens had a loss at one or other of these markers, thus indicating that a putative TSG(s) in this region may play a role in the development of the SCCHN. No correlation was found between the LOH data and any of the clinicopathological parameters. We also investigated the incidence of c-myc amplification in 144 SCCHN specimens but only 4% were found to have an amplified c-myc allele, thus indicating that the overexpression of c-myc in SCCHN was not the result of gene amplification. 相似文献
55.
This study computed life table probabilities of contraceptive failure, discontinuation of use, and return to contraceptive use in the US. Data were obtained from the 1995 National Survey of Family Growth (NSFG) among a nationally representative sample of 6867 contraceptive use intervals contributed by women 15-45 years old who began use or resumed use after discontinuation during 1991-95. Analysis was based on Kaplan-Meier product-limit single decrement life table probability methods. Findings indicate that the risk of failure during typical use of reversible methods was 9% within 1 year of starting. Women with continuous lifetime use will experience 1.8 contraceptive failures. Failure rates were 7% for the pill, 9% for the male condom, 8% for the diaphragm, 20% for periodic abstinence, and 15% for spermicides. Failure rates reflect imperfect use. 31% of women discontinued use within 6 months of starting use. 44% discontinued within 12 months. Women using reversible methods continuously will discontinue use nearly 10 times during the reproductive period. Most women resumed use shortly after discontinuation. Low income women had higher risk of unintended pregnancy for all methods and the pill and lower risk of resumption after discontinuation. Hispanics had a higher risk of contraceptive failure for all methods and the condom. Black women had a higher risk of discontinuation of oral pills and condoms. 相似文献
56.
Effect of dopamine denervation and dopamine agonist administration on serine phosphorylation of striatal NMDA receptor subunits 总被引:8,自引:0,他引:8
Sensitization of striatal N-methyl-d-aspartate (NMDA) receptors has been implicated in the pathogenesis of the response alterations associated with dopaminomimetic treatment of parkinsonian animals and patients. To determine whether serine phosphorylation of NMDA receptor subunits by activation of Ca2+/calmodulin-dependent protein-kinase II (CaMKII) contributes to this process, we examined the effects of unilateral nigrostriatal ablation with 6-hydroxydopamine and subsequent treatment with levodopa, SKF 38393 (D1-preferring dopamine agonist), or quinpirole (D2-preferring agonist) on motor responses and phosphorylation states. Three weeks of twice-daily levodopa administration to rats shortened the duration of their rotational response to levodopa or SKF 38393 challenge, but prolonged the duration of quinpirole-induced rotation. At the same time, levodopa treatment elevated serine phosphorylation of striatal NR2A (p<0.02), but not that of NR2B subunits, without associated changes in subunit protein levels. Chronic treatment with SKF 38393 increased NR2A (p<0.0001) but decreased NR2B (p<0.004) serine phosphorylation. In contrast, chronic quinpirole treatment had no effect on NR2A but increased NR2B phosphorylation (p<0.0001). The acute intrastriatal injection of the CaMKII inhibitor KN93 (1.0 micrograms) not only normalized the levodopa-induced motor response alterations but also attenuated the D1 and D2 receptor-mediated serine phosphorylation of NR2A and NR2B subunits, respectively (p<0.02). These results suggest that a CaMKII-mediated rise in serine phosphorylation of NMDA receptor subunits induced by intermittent stimulation of D1 or D2 dopaminergic receptors contributes to the apparent enhancement in striatal NMDA receptor sensitivity and thus to the dopaminergic response plasticity in levodopa-treated parkinsonian rats. 相似文献
57.
Lemack GE Szabo Z Urban Z Boyd CD Csiszar K Vaughan ED Felsen D 《Neurourology and urodynamics》1999,18(1):55-68
The elasticity of tissues subjected to repeated deformation is provided by the presence of elastic fibers in the extracellular matrix (ECM). The most abundant component of elastic fibers is elastin, whose soluble precursor is tropoelastin. To establish the role elastin plays in the bladder, this study describes the biosynthetic, histologic, and physiologic consequences of expression of an isoform of rat tropoelastin in transgenic mouse bladder. The polymerase chain reaction (PCR) was used to determine expression of a rat tropoelastin minigene in transgenic mice. Histochemical methods were used to demonstrate changes in elastic fibers in frozen sections of bladder. Cystometric analysis was carried out in transgenic and non-transgenic mice, prior to and after 3 weeks of partial outlet obstruction. The PCR assay demonstrated that bladder tissue of transgenic mice expressed rat tropoelastin mRNA, whereas non-transgenes did not. Increased deposition of elastic fibers was demonstrated with the Verhoeff-van Gieson stain. Bladders of transgenic animals were more compliant than bladders of their non-transgenic littermates. Partial outlet obstruction resulted in increased bladder volume and more compliant bladders in non-transgenic mice. In contrast, the bladder volume and compliance in transgenes was almost unchanged by obstruction. This study demonstrates that normal elastic fiber assembly is prerequisite for the compliant properties of the bladder wall. Moreover, the response of the bladder to obstruction is critically influenced by elastin synthesis. 相似文献
58.
Vaughan JP Mogedal S Kruse S Lee K Walt G de Wilde K 《Health policy (Amsterdam, Netherlands)》1996,35(3):229-245
From 1948, when WHO was established, the Organisation has relied on the assessed contributions of its member states for its regular budget. However, since the early 1980s the WHO World Health Assembly has had a policy of zero real growth for the regular budget and has had to rely increasingly, therefore, on attracting additional voluntary contributions, called extrabudgetary funds (EBFs). Between 1984-85 and 1992-93 the real value of the EBFs apparently increased by more than 60% and in the 1990-91 biennium expenditure of extrabudgetary funds exceeded the regular budget for the first time. All WHO programmes, except the Assembly and the Executive Board, receive some EBFs. However, three cosponsored and six large regular programmes account for about 70% of these EBFs, mainly for vertically managed programmes in the areas of disease control, health promotion and human reproduction. Eighty percent of all EBFs received by WHO for assisted activities have been contributed by donor governments, with the top 10 countries (in Europe, North America and Japan) contributing about 90% of this total, whereas the UN funds and the World Bank have donated only about 6% of the total to date. By contrast, about 70% of the regular budget expenditure has been for organisational expenses and for the support of programmes in the area of health systems. Despite the fact that the more successful programmes are heavily reliant on EBFs, there are strong indications that donors, particularly donor governments, are reluctant to maintain the current level of funding without major reforms in the leadership and management of the Organisation. This has major implications for WHO's international role as the leading UN specialised agency for health. 相似文献
59.
Effective chemotherapy of acute myelocytic leukemia occurring after alkylating agent or radiation therapy for prior malignancy 总被引:1,自引:0,他引:1
Eleven consecutive patients with acute myelocytic leukemia occurring as a second malignancy were treated with high-dose, timed, sequential chemotherapy. Eight of the patients were felt to have "secondary" acute leukemia because they had received an alkylating agent or radiation therapy. The other three patients were considered controls. Despite a median age of 65, four of the eight secondary leukemia patients achieved complete remission with this regimen. One of the three control patients also achieved complete remission. This remission rate and duration are comparable to what was achieved with this treatment of "primary" acute myelocytic leukemia during the same period of time. These results suggest that patients with leukemia occurring after an alkylating agent or radiation therapy are not at especially high risk if treated aggressively. 相似文献
60.
Peter Vaughan J. Mailen Kootsey Michael D. Feezor 《Pflügers Archiv : European journal of physiology》1991,419(5):522-528
At pH 5 the steady-state chloride chord conductance in frog skeletal muscle rises to an asymptotic maximum at very negative voltages and approaches an asymptotic minimum at positive voltages. When a two-pulse test paradigm is used, the conductance computed from steady-state currents during the first (conditioning) voltage step are not duplicated by the conductance at the onset of a second (test) step. If the test step is to a more negative voltage than the conditioning step the steady-state conductance is overestimated; if it is to a less negative voltage the conductance is underestimated. In some fibres the initial currents accompanying steps from the resting potential are inwardly rectified. From this it was inferred that chloride channel conductance is voltage dependent: in those fibres in which no such initial inward rectification was observed it was inferred that at rest the voltage-dependent chloride channels are all closed. Time-dependent (gated) changes of conductance could be reasonably described by a first-order process, but the relaxations were not simple exponentials. Simulation of the experimental set-up predicted the type of deviation from exponentiality seen experimentally, although the observed deviations were often more pronounced than those predicted. 相似文献