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71.

Background  

CD4+ T lymphocyte (CD4) cell count testing is the standard method for determining eligibility for antiretroviral therapy (ART), but is not widely available in sub-Saharan Africa. Total lymphocyte counts (TLCs) have not proven sufficiently accurate in identifying subjects with low CD4 counts. We developed clinical algorithms using TLCs, hemoglobin (Hb), and body mass index (BMI) to identify patients who require ART.  相似文献   
72.
Most issues of the instinct controversy were defined in the seventeenth century. Eighteenth-century French enlightenment was vigorous in rejecting the instinct concept but Reimarus demonstrated its validity. The advance of natural theology, and later of Darwinism, led to wide acceptance of instinct in the nineteenth century, but the twentieth witnessed a revival of anti-instinct attitudes on the eighteenth-century model. Extraneous influences still impede recognition of scientific evidence for the importance of innately determined behavior.Division 26, American Psychological Association, Montreal, Canada, August 1973 (revised).  相似文献   
73.
At the University of California, Irvine Medical Center, an end-of-life curriculum was implemented in 2000 for an internal medicine residency utilizing a longitudinal approach that allowed residents to follow patients through their entire hospice experience. An elective home hospice rotation was developed for which third-year residents served as primary care physicians for patients at the end of life over a one-year period. Residents were supervised by faculty who were hospice medical directors. They also learned through case vignettes, quarterly meetings, textbook reading, and personal projects. From July 2000 to June 2002, residents demonstrated positive attitudes towards hospice care and recommended the rotation highly (mean 8.86 on a scale of 1-10). The rotation grew in popularity from six initial residents to ten residents the next year, and has since become a mandatory rotation for all senior residents. A 360-degree evaluation uniformly indicated positive resident performance from the hospice team (mean scores 7.56-8.69 on a 1-9 scale), family (mean scores 9.3-9.7 on a 1-10 scale) and faculty (mean scores 7.29-7.72 on a 1-9 scale). Residents were also pleased with the level of teaching (mean 8.86 on a scale of 1-10) and felt that the patient care load was "just right." Their knowledge improved by 8% (p =.0175). In conclusion, a longitudinal hospice rotation was implemented that fulfilled curricular goals without undue burden on the residents or residency program.  相似文献   
74.
Racism is associated with increased psychosocial stress and blood pressure in blacks. However, little is known of the relationship of racism to other features of insulin resistance syndrome. This study examined the relationship of internalized racism to abdominal obesity and elevated blood pressure in a population of black Caribbean women aged 20-55 years. One hundred thirty-three randomly selected women from the island of Barbados comprised the study sample. Data collected included anthropometric and blood pressure measurements, and information about internalized racism, anxiety, and depression. The stress measures including anxiety, depression, and internalized racism were significantly correlated with waist circumference (r = .25, r = .21, and r = .25). After adjusting for age, education, anxiety, and depression, internalized racism remained significantly correlated with waist circumference. The odds ratio associated with development of abdominal obesity among those with high internalized racism (OR = 2.4 [95% CI, 1.1,5.3]) was significant (P < .05) after adjusting for age, education, and body mass index. Blood pressure was not independently related to internalized racism. Studies comparing black-white differences in diseases for which abdominal obesity is a risk factor (eg, diabetes and cardiovascular disease) should take into account the potential role of internalized racism in defining the differences between ethnic groups.  相似文献   
75.
76.
Ketamine protects hippocampal neurons from anoxia in vitro   总被引:7,自引:0,他引:7  
Ketamine, a dissociative, general anesthetic, blocks the excitation produced by activating one class of excitatory amino acid receptors, the N-methyl-D-aspartate receptor in the rat. We have found that ketamine can protect hippocampal neurons in culture and slice from anoxia. When added to cultures immediately prior to anoxic exposure, ketamine prevented the neuronal destruction seen after a day of anoxia. Neurons appeared undamaged and had normal resting and action potentials. Adenosine triphosphate levels in ketamine-protected anoxic cultures were approximately two-thirds of normal controls. Ketamine also prevented the irreversible loss of the population spike seen in hippocampal slices after prolonged perfusion with anoxic buffer. These results suggest that ketamine may have therapeutic potential in preventing anoxic damage from stroke in man.  相似文献   
77.
Purification of ovocalyxin-32, a novel chicken eggshell matrix protein   总被引:1,自引:0,他引:1  
The eggshell is a highly ordered structure resulting from the deposition of calcium carbonate and an organic matrix from the acellular uterine fluid. Characterization of the individual matrix components is necessary to determine their influence upon calcite crystal shape, size, and orientation during eggshell calcification. We have purified and sequenced a novel 32-kDa protein, ovocalyxin-32 (OCX-32), which is present at high levels in the uterine fluid during the terminal phase of eggshell formation, and is localized predominantly in the outer eggshell. Database searches identified expressed sequence tags (ESTs) whose alignment yielded the complete cDNA. OCX-32 protein possesses limited identity (32%) to two unrelated proteins: latexin, a carboxypeptidase inhibitor expressed in rat cerebral cortex and mast cells, and to a skin protein that is encoded by a retinoic acid receptor-responsive gene, TIG1. The timing of OCX-32 secretion into the uterine fluid suggests that it may play a role in the termination of mineral deposition.  相似文献   
78.
Objective: Previous work has shown that manic-depressive illness and alcohol abuse are linked. This study further explores the relationship of alcohol and drug abuse in bipolar I patients and unipolar depressives and a comparison group obtained through the acquaintance method. Method: Diagnosis was accomplished according to Research Diagnostic Criteria (RDC): controls=469; bipolars=277; unipolar depressives=678. Systematic data were gathered using the SADS on lifetime and current drug abuse and alcoholism. Both patients and comparison subjects were then followed prospectively for 10 years. First degree family members were interviewed using the RDC family history method. Results: The group of bipolar patients and the group of unipolar patients had higher rates of drug and alcohol abuse than the comparison group when primary and secondary affective disorder patients were combined. However, primary unipolar patients did not have higher rates of alcohol or drug abuse than the comparison group. In contrast, primary bipolar patients had higher rates of alcoholism, stimulant abuse, and ever having abused a drug than the primary unipolar group and the control group. In an evaluation of the bipolar patients, drug abusers were significantly younger at intake and had a significantly younger age of onset of bipolar disorder. There was a significant increase in family history of mania or schizoaffective mania in the drug-abusing bipolar patients as compared to the non-abusing bipolar patients. Limitation: As in all adult samples of patients with affective illness, the chronology of alcohol and substance problems vis-à-vis the onset of illness was determined retrospectively. Conclusions: (1) Alcoholism and drug abuse are more frequent in bipolar than unipolar patients. (2) The drug abuse of bipolar patients tends toward the abuse of stimulant drugs. (3) In a bipolar patient, familial diathesis for mania is significantly associated with the abuse of alcohol and drugs. (4) More provocatively, these findings suggest the hypothesis of a common familial-genetic diathesis for a subtype of bipolar I, alcohol and stimulant abuse. Clinical implications: The present analyses, coupled with two previous ones from the CDS, suggest that drug abuse may precipitate an earlier onset of bipolar I disorder in those who already have a familial predisposition for mania. Furthermore, in dually diagnosed patients with manic-depressive and alcohol/stimulant abuse history, mood stabilization of the bipolar disorder represents a rational approach to control concurrent alcohol and drug problems, and should be studied in systematic controlled trials.  相似文献   
79.
BACKGROUND: The present analyses were designed to compare the clinical characteristics and long-term episode course of Bipolar-I and Bipolar-II patients in order to help clarify the relationship between these disorders and to test the bipolar spectrum hypothesis. METHODS: The patient sample consisted of 135 definite RDC Bipolar-I (BP-I) and 71 definite RDC Bipolar-II patients who entered the NIMH Collaborative Depression Study (CDS) between 1978 and 1981; and were followed systematically for up to 20 years. Groups were compared on demographic and clinical characteristics at intake, and lifetime comorbidity of anxiety and substance use disorders. Subsets of patients were compared on the number and type of affective episodes and the duration of inter-episode well intervals observed during a 10-year period following their resolution of the intake affective episode. RESULTS: BP-I and BP-II had similar demographic characteristics and ages of onset of their first affective episode. Both disorders had more lifetime comorbid substance abuse disorders than the general population. BP-II had a significantly higher lifetime prevalence of anxiety disorders in general, and social and simple phobias in particular, compared to BP-I. Intake episodes of BP-I were significantly more acutely severe. BP-II patietns had a substantially more chronic course, with significantly more major and minor depressive episodes and shorter inter-episode well intervals. BP-II patients were prescribed somatic treatment a substantially lower percentage of time during and between affective episodes. LIMITATIONS: BP-I patients with severe manic course are less likely to be retained in long-term follow-up, whereas the reverse might be true for BP-II patients who are significantly more prone to depression (i.e., patients with less inclination to depression and with good prognosis may have dropped out in greater proportions); this could increase the gap in long term course characteristics between the two samples. The greater chronicity of BP-II may be due, in part, to the fact that the patients were prescribed somatic treatments substantially less often both during and between affective episodes. CONCLUSIONS: The variety in severity of the affective episodes shows that bipolar disorders, similar to unipolar disorders, are expressed longitudinally during their course as a dimensional illness. The similarities of the clinical phenotypes of BP-I and BP-II, suggest that BP-I and BP-II are likely to exist in a disease spectrum. They are, however, sufficiently distinct in terms of long-term course (i.e., BP-I with more severe episodes, and BP-II more chronic with a predominantly depressive course), that they are best classified as two separate subtypes in the official classification systems.  相似文献   
80.
Two enzyme-linked immunosorbent assays were established and compared for the estimation of plasma aldosterone. In the first method immobilized aldosterone-protein complexes on the ELISA plates compete with aldosterone to be determined for the binding of certain amount of anti-aldosterone antibodies. The sensitivity of this method depends on the protein carrier used to conjugate with aldosterone. In the second method, anti-aldosterone antibodies adsorbed on ELISA plates compete for binding of known amount of the enzyme-labeled aldosterone and aldosterone to be determined. The highly specific rabbit anti-aldosterone antibodies were obtained by injection of aldosterone-oxime thyroglobulin. The detection limit of aldosterone in both methods ranged between 2-20 pg. The proposed assays are suitable for the determination of aldosterone in biological fluids compared with other reported ELISA assays, as well as with RIA.  相似文献   
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