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51.
52.
Grimes AL McCullough LB Kunik ME Molinari V Workman RH 《Psychiatric services (Washington, D.C.)》2000,51(12):1561-1567
The authors examine the less-studied components of patients' autonomous decision making, or decisional autonomy, in the light of current research in psychiatry and neuropsychology and developments in the construct of informed consent. The three components of decisional autonomy-understanding, intentionality, and noncontrol or voluntariness-are related to clinical constructs in psychiatry and neuropsychology, in particular to executive control functions. The authors review studies that examine deficits in prefrontal cerebral function in schizophrenia, depression, and some anxiety disorders that are related to intentionality and voluntariness. Assessment of decisional autonomy should encompass evaluation of impaired intentionality and voluntariness, not simply impaired understanding. The main response to finding such impairments should be to provide treatment to ameliorate them. New strategies for psychiatric care should be developed to address the clinical challenges of an increasingly complex view of decisional autonomy. 相似文献
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OBJECTIVE: To describe the effect of an extended-spectrum prophylactic antibiotic regimen on postcesarean endometritis. METHODS: This is a cohort study of trends in postcesarean endometritis using data both from prospective surveillance by the infection control unit and from query of our obstetric computerized database to compare three periods of antibiotic prophylaxis: standard narrow-spectrum with intravenous first- or second-generation cephalosporin (1992-1996), clinical trial of extended-spectrum with addition of intravenous doxycycline and oral azithromycin (1997-1999), and routine use of extended-spectrum with addition of intravenous azithromycin (2001-2006) to standard cephalosporin prophylaxis. RESULTS: A total of 48,913 deliveries at 24 weeks or more of gestation occurred from 1992 to 2006, of which 10,966 (22.4%) were cesarean deliveries. Annual cesarean rates increased from 16% to 27.5%. Trends in the incidence of postcesarean endometritis revealed a biphasic decrease consistent with the phased introduction of extended-spectrum prophylaxis. Incidence (95% confidence interval [CI]) of endometritis by prospective surveillance dropped from 19.9% (95% CI 18.6-21.3%) to 15.4% (95% CI 13.2-17.9%) during the clinical trial period: relative risk (RR) 0.77 (95% CI 0.66-0.91), P=.002; and then to 6.3% (95% CI 5.0-7.9%) during routine use of extended-spectrum prophylaxis: RR 0.41 (95% CI 0.31-0.54), P<.001. Corresponding incidence by database query dropped from 23% (95% CI 21.5-24.4%) to 16% (95% CI 14.4-17.9%): RR 0.69 (95% CI 0.61-0.79), P<.001; and then to 2.1% (95% CI 1.8-2.6%): RR 0.13 (95% CI 0.11-0.16), P<.001. These findings were unchanged after adjusting for potential confounders. CONCLUSION: Extended-spectrum antibiotic prophylaxis involving the addition of azithromycin to standard narrow-spectrum prophylaxis was associated with a significant reduction in postcesarean endometritis. LEVEL OF EVIDENCE: II. 相似文献
55.
The Greek-based terms used to describe semen-analysis abnormalities (e.g., "oligozoospermia" and "azoospermia") are unscientific, have overlapping definitions, and are often misinterpreted. The best course is to abandon these vague and difficult labels and simply report semen analyses quantitatively. 相似文献
56.
Advance provision of emergency contraception for pregnancy prevention: a meta-analysis 总被引:2,自引:0,他引:2
Polis CB Schaffer K Blanchard K Glasier A Harper CC Grimes DA 《Obstetrics and gynecology》2007,110(6):1379-1388
OBJECTIVE: Advance provision of emergency contraception can circumvent some obstacles to timely use. We performed a meta-analysis to summarize randomized controlled trials evaluating advance provision of emergency contraception to explore effects on pregnancy rates, sexually transmitted infections, and sexual and contraceptive behaviors. DATA SOURCES: In August 2006, we searched CENTRAL, EMBASE, POPLINE, MEDLINE, a specialized emergency contraception article database, and contacted experts to identify published or unpublished trials. METHODS OF STUDY SELECTION: We included randomized controlled trials comparing advance provision to standard access, defined as any of the following: counseling (with or without information about emergency contraception) or provision of emergency contraception on request at a clinic or pharmacy. TABULATION, INTEGRATION AND RESULTS: Two reviewers independently assessed study quality. We performed a meta-analysis using Review Manager software. Eight randomized controlled trials met inclusion criteria, representing 6,389 patients in the United States, China, and India. Advance provision did not decrease pregnancy rates, despite increased use (single use, odds ratio [OR] 2.52, 95% confidence interval [CI] 1.72-3.70; multiple use: OR 4.13, 95% CI 1.77-9.63) and faster use (weighted mean difference -14.6 hours, 95% CI -16.77 to -12.4 hours). Advance provision did not increase rates of sexually transmitted infections (OR 0.99, 95% CI 0.73-1.34), unprotected intercourse, or changes in contraceptive methods. Women who received emergency contraception in advance were as likely to use condoms as other women. CONCLUSION: Advance provision of emergency contraception did not reduce pregnancy rates and did not negatively affect sexual and reproductive health behaviors and outcomes compared with conventional provision. LEVEL OF EVIDENCE: III. 相似文献
57.
58.
Familial protein S deficiency with a variant protein S molecule in plasma and platelets 总被引:3,自引:0,他引:3
A protein S deficient family presenting a variant protein S molecule in plasma and platelets is described. The propositus, age 20, and two brothers suffered from venous thrombotic disease. The propositus, the only family member studied while taking oral anticoagulants, had a protein S antigen (ag) level of 17% and undetectable activity. As demonstrated by immunoblotting both the propositus and one clinically affected brother (42% ag, 7% activity) presented variant protein S molecules of 65,000 molecular weight (mol wt) while the other clinically affected brother (64% ag, 11% activity) had only protein S with normal electrophoretic mobility of 70,000 mol wt. The mother had normal protein S levels (93% ag, 100% activity) but had both normal and variant protein S molecules and based on her functional protein S data a normal anticoagulant activity of the variant molecule is suggested. One asymptomatic but protein S deficient sister (68% ag, 9% activity) as well as the asymptomatic protein S deficient father (59% ag, 10% activity) had only protein S molecules of 70,000 mol wt. The variant protein S bound to C4b-binding protein in plasma, and differed from normal protein S in carbohydrate content. Platelets of each family member contained the same immunoblotting pattern of normal and variant protein S forms as found in plasma, consistent with the hypothesis that protein S gene expression involves codominant expression of two alleles that is similar in cells that control the synthesis of both platelet and plasma forms of protein S. 相似文献
59.
Crosslinking the CD27 antigen on T cells provides a costimulatory signal that, in concert with T-cell receptor crosslinking, can induce T- cell proliferation and cellular immune activation. We find that chronic lymphocytic leukemia (CLL) B cells from most patients coexpress both membrane-bound and soluble CD27, along with its newly identified ligand, CD70. The expression of soluble CD27 may preclude leukemic B cells from stimulating T cells via CD70, thereby potentially impairing their ability to function as effective antigen-presenting cells. We find that leukemic B-cell expression of soluble and membrane-bound CD27 can be downmodulated through a CD40-dependent signal. This signal also induces enhanced expression of CD70 on both normal and leukemic B cells. We find that tumor necrosis factor (TNF)-alpha, or the Th1 cytokine interferon (IFN)-gamma, also can induce downmodulation of CD27, whereas Th2-associated cytokines interleukin-4 (IL-4) or IL-10 can enhance leukemic B-cell expression of this accessory molecule. The modulation of CD27 induced by these conditions is accompanied by reciprocal changes in the expression levels of CD70, suggesting that these accessory molecules may be engaged in reciprocal receptor-ligand downmodulation. Consistent with this, we observe that co-culture of CLL B cells with transfected murine plasmacytoma cells that express human CD70 affects downmodulation of CD27 and enhanced expression of CD70 on leukemic B cells, but does not affect expression of CD27 mRNA. However, we find that CD40-crosslinking, in addition to reducing the level of CD27 protein, also reduces leukemic B-cell expression of CD27 mRNA. This argues that the changes in the expression levels of CD27 following CD40-signaling are not simply due to induced increases in the expression levels of CD70. Finally, we demonstrate that reciprocal changes in expression of CD27 and CD70 may contribute to the enhanced antigen-presenting capacity of CLL B cells after CD40-dependent leukemic B-cell activation. These findings expand the understanding of the regulation of costimulatory molecules important in antigen presentation and also have implications for the immunobiology of and therapy for CLL. 相似文献
60.
L M Demeter M D Hughes R W Coombs J B Jackson J M Grimes R J Bosch S A Fiscus S A Spector K E Squires M A Fischl S M Hammer 《Annals of internal medicine》2001,135(11):954-964
BACKGROUND: A substantial proportion of patients with HIV infection will not respond to antiretroviral therapy. Early predictors of response to treatment are needed to identify patients who are at risk for treatment failure. OBJECTIVE: To determine predictors of virologic and clinical response to indinavir, zidovudine, and lamivudine therapy. DESIGN: Observational analysis of one treatment group in a phase III trial. SETTING: 40 AIDS Clinical Trials units. PATIENTS: 489 patients receiving indinavir, zidovudine, and lamivudine who had 1) a CD4 count of 0.200 x 10(9) cells/L or less after 8 or more weeks of study therapy and 2) plasma HIV-1 RNA measurements obtained at baseline and week 8. MEASUREMENTS: HIV-1 RNA level and CD4 cell count at weeks 0, 4, 8, 24, and 40. Clinical progression was defined as a new AIDS-defining illness or death. RESULTS: Patients' levels of HIV-1 RNA at the 8th study week of therapy predicted whether patients would achieve virologic suppression to below 500 (or 50) copies/mL at study week 24. An HIV-1 RNA level less than 500 copies/mL at week 24 was achieved in 71% of patients whose level at week 8 had been less than 500 copies/mL, 53% of those with a level of 500 copies/mL or more and at least 2-log(10) copies/mL reduction since baseline, 29% of those with a level of 500 copies/mL or more with a 1- to 1.99-log(10) copies/mL reduction, and 9% of those with a level of 500 copies/mL or greater and less than 1-log(10) copies/mL reduction since baseline (P < 0.001). HIV-1 RNA level at week 8 also predicted clinical progression. HIV-1 disease progressed in 2.2% of the patients with a week-8 HIV-1 RNA level less than 500 copies/mL, 2.3% of patients with 500 copies/mL or greater and at least 2-log(10) copies/mL reduction since baseline, 4.9% of patients with 500 copies/mL or greater and 1- to 1.99-log(10) copies/mL reduction since baseline, and 10.6% of patients with 500 copies/mL or greater and less than 1-log(10) copies/mL decrease since baseline (P = 0.009). After adjustment for HIV-1 RNA level, patients with a higher week-8 CD4 cell count were more likely to have a week-24 HIV-1 RNA level less than 500 copies/mL (relative risk for patients with a week-8 CD4 count >/= 0.10 x 10(9) cells/L, 1.47 [95% CI, 1.00 to 2.16] compared with <0.050 x 10(9) cells/L; relative risk for patients with a week-8 CD4 count of 0.05 to 0.099 x 10(9) cells/L, 0.98 [CI, 0.61 to 1.57] compared with <0.050 x 10(9) cells/L). After adjustment for HIV-1 RNA level, patients with a week-8 CD4 count of 0.05 x 10(9) cells/L or greater (compared with <0.05 x 10(9) cells/L) had a decreased hazard for clinical progression (hazard ratio, 0.25 [CI, 0.09 to 0.67]). CONCLUSIONS: The HIV-1 RNA level and CD4 cell count achieved at 8 weeks of treatment are important predictors of subsequent virologic and clinical outcomes. 相似文献