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A case history illustrating the use of hypnosis in the retrieval of memory loss due to post-traumatic retrograde amnesia is described. This information was subsequently accepted as admissible in court proceedings. This report has implications for the process of the laying down of memory, and adds support to the retrieval failure hypothesis and the catalogue model of memory formation, with virtually instantaneous encoding of memory. It is also potentially of importance in that it provides a precedent for the acceptance by courts of law of previously amnesic information retrieved by means of hypnosis.  相似文献   
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This qualitative study is intended to elucidate Lakota elders’ views on traditional tobacco and commercial/addictive tobacco use, capturing the oral history that depict the cultural protocol regarding traditional tobacco, called Cansasa. Commercial tobacco use has significantly impacted the Northern Plains Indians. National surveillance systems report that tobacco use is more prevalent among American Indian/Alaska Natives than any other population, and is notably higher than the national average. Lung cancer among Native Americans is highest in the Northern Plains and Alaska, where smoking prevalence is also the highest, and smoking is responsible for nearly 90 % of all lung cancer cases. Yet, the use of traditional tobacco is largely ignored by surveillance and seems to have a distinct, positive role. Using a community-based participatory research approach, semi-structured interviews, and qualitative analysis tools, the research team, including 2 Lakota tribe elders, Lakota speaking tribal college students, and university faculty, sought to discern tribal elders’ distinctions between traditional and the addictive commercial tobacco. The team interviewed thirty Lakota elders, transcribed the interviews and field notes, and analyzed them using immersion/crystallization organizing framework. The research design engaged the Lakota tribal community in all stages, from planning to publication. Analysis revealed a clear distinction between traditional and commercial tobacco: tribal elders conveyed strong positive messages connected to traditional tobacco use (i.e., spirituality, respect, health and wellness, humility, and thoughtfulness) versus strong negative messages linked to addictive tobacco (i.e., crime, loss of control and self-esteem, lack of respect to self and others, sickness and death). These messages, along with stories in the Lakota language that were told and recorded during the interviews, can guide new ways to address addictive tobacco prevention in this community, to enhance cultural pride, and to serve as a cross-generation bridge regarding tobacco use.  相似文献   
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In the Pacific Northwest, cancer is a leading cause of morbidity and mortality for American Indians and Alaska Natives (AI/AN). Misclassification of AI/AN race in state cancer registries causes cancer burden to be underestimated. Furthermore, local-level data are rarely available to individual tribes for use in health assessment and program planning. We corrected race coding in the cancer registries of Idaho, Oregon, and Washington using probabilistic record linkage to a file derived from patient registration records from Indian Health Service and a large urban clinic. We calculated cancer incidence and mortality measures by state, comparing AI/AN to non-Hispanic White (NHW) race. Record linkages identified a high prevalence of misclassified race. Differences in AI/AN cancer patterns were identified across the three state region. Compared to NHW, AI/AN experienced disproportionate late stage rates of some screen-detectable cancers. The correct classification of race is a crucial factor in cancer surveillance and can reveal regional differences even within a relatively small area. The availability of local-level cancer data can help inform tribes in appropriate intervention efforts.  相似文献   
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Signal transduction by the platelet Fc receptor   总被引:6,自引:1,他引:6  
Anderson  GP; Anderson  CL 《Blood》1990,76(6):1165-1172
We have evaluated the mechanism by which crosslinking human platelet Fc receptor (FcR) for IgG triggers platelet aggregation and the platelet release reaction. Platelet FcR was crosslinked by incubating purified human platelets with anti-FcRII monoclonal antibody and F(ab')2 anti- mouse Ig. The resultant [Ca2+]i increase, monitored by Fura-2 and measured in the absence of extracellular Ca2+, reached a peak of 750 +/- 50 nmol/L. The effects of cyclooxygenase inhibitors, aspirin and indomethacin, and a phospholipase A2 inhibitor, dibromoacetophenone, were examined. Regardless of the inhibitor, at least 25% of the [Ca2+]i increase remained. Thrombin (0.2 U/mL) stimulated an immediate [Ca2+]i increase that reached 1.95 +/- 0.8 mumol/L. The [Ca2+]i increase generated by thrombin was only slightly reduced by these inhibitors. Crosslinking the FcRII of platelets resulted in a fivefold increase in the production of [3H]inositol phosphates, (IP) which, in the absence of extracellular Ca2+ was insensitive to aspirin. The activation of a [Ca2+]i increase along with the measured increases in IP indicate that FcRII crosslinking leads to the activation of phospholipase C (PLC). In contrast to thrombin, platelet activation via FcRII depends to a large extent on arachidonic acid metabolites. However, neither cyclooxygenase nor phospholipase A2 inhibitors completely blocked FcRII-stimulated [Ca2+]i increase. These observations led us to propose that crosslinking of platelet FcRII initially activates PLC.  相似文献   
17.

Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.  相似文献   
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Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.  相似文献   
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Circulating levels of corticosteroids and androgens have been studied in the brush-tailed possum (Trichosurus vulpecula) under conditions of tropic hormone stimulation. In both males and anestrous females, levels of androgen (considered to consist largely of testosterone) were elevated by 3 days of treatment with PMS. Further treatment with ACTH (Synacthen) subsequently reduced the level of testosterone in the females to values significantly below the control values, and in the male to a value intermediate between control and PMS stimulated levels. Levels of corticosteroid (considered to consist largely of cortisol) were unaffected by gonadotropin treatment, but significantly increased with ACTH. Dexamethasone treatment greatly decreased cortisol levels, but androgen levels were unaffected in both sexes.In vitro androgen production by the definitive adrenal cortex of the female was significantly decreased by dexamethasone pretreatment. Androgen production by a special hypertrophied adrenocortical zone was unaffected. Corticosteroid formation was reduced in both types of tissue.It is concluded that the adrenal cortex contributes to circulating testosterone levels in the female possum. This is supported by gonadotropin, whereas ACTH has a double effect of stimulating overall steroidogenesis, but switching the relative proportions of the steroids by decreasing the synthesis of androgen and stimulating the corticosteroid pathway. The possible physiological role for this phenomenon and the function of the special hypertrophied zone in the female adrenal cortex are discussed.  相似文献   
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