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Questionable data and preconceptions: reconsidering the value of mammography for American Indian Women. 总被引:3,自引:1,他引:2
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Although the benefits of mammography are well established, many remain skeptical of the value of mammography for American Indian women. This skepticism stems in part from a belief that breast cancer is too rare an event among American Indians to warrant widespread screening. The validity of this assumption for Northern Plains Indians is challenged by a discussion of the limitations of available data on breast cancer in American Indian populations (including lack of generalizability, underestimation, and an overreliance on relative rather than absolute measures of cancer incidence) and by findings from the Minnesota Breast and Cervical Cancer Control Program, a federally funded program providing free breast and cervical cancer screening to American Indian and other women in Minnesota. In light of this information, the authors recommend that the low priority of mammography for American Indian women be reconsidered. 相似文献
6.
This study investigated the relationship between increased serotonin (5-hydroxytryptamine, 5HT) receptor sensitivity and human aggression. A low oral dose of meta-chlorophenylpiperazine (MCPP), a postsynaptic 5HT receptor agonist, was administered in a placebo-controlled design to depressed (n = 22) and panic disorder (n = 20) patients classified with or without signs of outwardly directed aggression, patients with a history of suicide attempts (inwardly directed aggression) (n = 11), and normal controls (n = 19). Hormones under 5HT control were measured at 30-min intervals. Results were as follows: (1) MCPP did not induce or reduce anger, (2) patients with outwardly directed aggression did not have significantly greater MCPP-induced cortisol or prolactin release than did patients without signs of outwardly directed aggression, (3) patients with a history of suicide attempts did not have significantly greater MCPP-induced cortisol or prolactin release than did normal controls, and (4) MCPP-induced hormone release was unrelated to measures of aggression. 相似文献
7.
A Gossler T Doetschman R Korn E Serfling R Kemler 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(23):9065-9069
This study demonstrates that blastocyst-derived embryonic stem cells (ES cells) can be used as a vehicle for transgenesis. The method is nearly as efficient as other methods, and the introduced neomycin phosphotransferase (neo) gene is stably transmitted through several generations with no apparent loss in G418 resistance. An important factor contributing to the efficiency of this process is the rigorous selection, before blastocyst injection, of genetically transformed cells for in vitro developmental pluripotency. One of the advantages of the ES cell route to transgenesis is that it provides investigators with the opportunity to screen for the desired genetic alterations before reintroducing the ES cells into the animal. 相似文献
8.
Liana Beni-Adani Naresh Biani Liat Ben-Sirah Shlomi Constantini 《Child's nervous system》2006,22(12):1543-1563
Background and objective The classification of hydrocephalus in newborns and in infants is different from the classification in adulthood. This difference
exists due to disparity in the source pathologies that produce the hydrocephalus, and the practical distinctions in prognosis
and treatment choices. The objective of this paper is to present the spectrum of obstructive-communicating hydrocephalus,
which is more complex in the pediatric group, and to propose the relevance of this particular classification to treatment
options.
Materials and methods The authors categorized infants with active hydrocephalus at time of presentation into the following four groups along the
spectrum of communicating vs obstructive HCP. Group 1: patients with a purely absorptive (communicating) HCP. In these patients,
tetraventricular dilatation is usually observed with occasional extraaxial fluid accumulation. An extracranial CSF diversion
(shunt) is the treatment of choice. Group 2: patients with an obstructive component together with a persistent absorptive
component. In these patients, a technically successful endoscopic procedure will not prevent progression of clinical symptoms
of HCP. An extracranial CSF diversion (shunt) should be the treatment of choice even though some of these patients are currently
treated by endoscopy. Group 3: patients with an obstructive component together with a temporary absorptive component. In these
patients, a technically successful ETV should be followed by temporary CSF drainage [via LP, continuous spinal drainage (CLD),
or ventriculostomy] with or without supplemental medical treatment (i.e., Diamox) for several days. Such temporary drainage
may decrease failure rate in this subgroup. Group 4: patients with a purely obstructive HCP. In these patients, an endoscopic
procedure (ETV) is the treatment of choice. According to this spectrum classification, the authors classify different entities
with representative cases and discuss relevancy to treatment options and prognosis.
Results The data suggest that obstructive hydrocephalus in the very young population may be rather a combination of obstructive and
absorptive problem. The outcome of the patient depends mainly not only on the basic pathology causing the hydrocephalus but
also on the treatment that is chosen and its complications. While bleeding and infection represent the major causes for communicating
hydrocephalus, patients with complex pathologies of congenital type and intra- or interventricular obstructions may reflect
obstructive hydrocephalus. Treatment of these patients may be successful by shuntless procedures if the absorptive problem
is not the major component. In transient absorptive hydrocephalus, temporary measures were effective in many cases leading
to successful procedures of ETV and/or posterior-fossa decompression in selected cases.
Conclusions Shuntless procedures are the dream of a pediatric neurosurgeon provided it solves the problem and does not imply unacceptable
risk. However, the benefit has to be evaluated years after the procedure is performed, as only prospective multicenter studies
will truly show which procedure may have the best overall results in the developing child. Until such studies are available,
understanding the basic pathology or the combination of pathologies leading to hydrocephalus in a given child may open the
window of opportunities for other than shunt surgery in many hydrocephalic children with major obstructive component. 相似文献
9.
Adherence to continuous positive airway pressure treatment in patients with Alzheimer's disease and obstructive sleep apnea. 总被引:2,自引:0,他引:2
Liat Ayalon Sonia Ancoli-Israel Carl Stepnowsky Matthew Marler Barton W Palmer Lianqi Liu Jose S Loredo Jody Corey-Bloom Deborah Greenfield Jana Cooke 《The American journal of geriatric psychiatry》2006,14(2):176-180
OBJECTIVE: This analysis examined whether patients with Alzheimer disease (AD) tolerate continuous positive airway pressure (CPAP). METHOD: Thirty patients with AD were randomized to CPAP or sham CPAP and completed sleep, depression, and quality-of-life questionnaires. Participants could choose to continue treatment after the trial. RESULTS: Patients wore CPAP for 4.8 hours per night. More depressive symptoms were associated with worse adherence (rS=-0.37; N=30, p<0.04). Patients who continued using CPAP had fewer depressive symptoms (t [19]=2.45, p=0.02) and better adherence (t [19]=2.32, p=0.03) during the trial. CONCLUSION: Patients with AD with obstructive sleep apnea can tolerate CPAP. Adherence and long-term use may be more difficult among those patients with more depressive symptoms. 相似文献
10.
Nordihydroguaiaretic acid inhibits voltage-activated Ca2+ currents independently of lipoxygenase inhibition 总被引:7,自引:0,他引:7
The effects of nordihydroguaiaretic acid (NDGA), a widely used lipoxygenase inhibitor, were examined on voltage-activated Ca2+ channel currents in GH3 and AtT-20 pituitary cells. NDGA (10-100 microM) produced a reversible, dose-dependent inhibition of Ca2+ channel currents, with half-maximal inhibition occurring at 18.6 microM. Inhibition by NDGA developed relatively slowly, did not exhibit use dependence or voltage dependence, and did not require access of NDGA to the extracellular domain of the Ca2+ channel. The maximum inhibition of macroscopic currents by 30 microM NDGA was equivalent in the presence of 5 and 50 mM extracellular Ca2+ and 5 mM Ba2+. NDGA inhibited Ca2+ channel currents in excised, outside-out patches, in the absence of intra- and extracellular Ca2+ (with Ba2+ as the charge carrier), and following preincubation of the cells with the phospholipase A2 inhibitor 4-bromophenacylbromide. Of five other lipoxygenase inhibitors tested, only one inhibited Ca2+ currents. These results suggest that NDGA inhibits Ca2+ channel currents by a mechanism distinct from that of other known Ca2+ channel antagonists and that, when influx of Ca2+ through voltage-gated channels is involved, inhibition of Ca2(+)-dependent cell functions by NDGA (greater than 10 microM) may be independent of effects on arachidonic acid metabolism. 相似文献