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1.

Forensic age estimation generally involves considerable amounts of uncertainty. Forensic age indicators such as teeth or skeleton images predict age only approximately, and this is likely to remain true even for future forensic age indicators. Thus, forensic age assessment should aim to make the best possible decisions under uncertainty. In this paper, we apply mathematical theory to make statistically optimal decisions to age assessment. Such an application is fairly straightforward assuming there is a standardized procedure for obtaining age indicator information from individuals, assuming we have data from the application of this procedure to a group of persons with known ages, and assuming the starting point for each individual is a probability distribution describing prior knowledge about the persons age. The main problem is then to obtain such a prior. Our analysis indicates that individual priors rather than a common prior for all persons may be necessary. We suggest that caseworkers, based on individual case information, may select a prior from a menu of priors. We show how information may then be collected over time to gradually increase the robustness of the decision procedure. We also show how replacing individual prior distributions for age with individual prior odds for being above an age limit cannot be recommended as a general method. Our theoretical framework is applied to data where the maturity of the distal femur and the third molar is observed using MRI. As part of this analysis we observe a weak positive conditional correlation between maturity of the two body parts.

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2.
Throughout Africa, Peer Mentors who are women living with HIV (WLH) are supporting pregnant WLH at antenatal and primary healthcare clinics (McColl in BMJ 344:e1590, 2012). We evaluate a program using this intervention strategy at 1.5 months post-birth. In a cluster randomized controlled trial in KwaZulu-Natal, South Africa, eight clinics were randomized for their WLH to receive either: standard care (SC), based on national guidelines to prevent mother-to-child transmission (4 clinics; n = 656 WLH); or an enhanced intervention (EI; 4 clinics; n = 544 WLH). The EI consisted of four antenatal and four postnatal small group sessions led by Peer Mentors, in addition to SC. WLH were recruited during pregnancy and 70 % were reassessed at 1.5 months post-birth. EI’s effect was ascertained on 16 measures of maternal and infant well-being using random effects regressions to control for clinic clustering. A binomial test for correlated outcomes evaluated EI’s overall effectiveness. Among EI WLH reassessed, 87 % attended at least one intervention session (mean 4.1, SD 2.0). Significant overall benefits were found in EI compared to SC using the binomial test. However, it is important to note that EI WLH were significantly less likely to adhere to ARV during pregnancy compared to SC. Secondarily, compared to SC, EI WLH were more likely to ask partners to test for HIV, better protected their infants from HIV transmission, and were less likely to have depressed mood and stunted infants. Adherence to clinic intervention groups was low, yet, there were benefits for maternal and infant health at 1.5 months post-birth.  相似文献   
3.
BACKGROUND: Breast cancer diagnosis and treatment may put women at higher risk for osteoporosis in later life. METHODS: In a subgroup of participants in the Women's Health Initiative Observational Study, authors of the current study investigated differences in bone mineral density (BMD, measured by dual-energy x-ray absorptiometry) between breast cancer survivors (n = 209) and a noncancer reference group (n = 5759). RESULTS: In comparison to the reference group, breast cancer survivors had significantly lower total body BMD value (0.989 vs. 1.013 g/cm(2), P = 0.001) and total hip BMD value (0.823 vs. 0.845 g/cm(2), P = 0.02) at baseline after adjustment for age, race/ethnicity, years since menopause, and clinical center. These lower BMD levels were largely explained by lower usage of hormone therapy (HT) among survivors: after additional statistical adjustment for HT, hip BMD values were 0.834 versus 0.844 g/cm(2) (P = 0.26), and total body values were 1.005 versus 1.013 g/cm(2) (P = 0.33) for survivors and reference women, respectively. More than 77% of survivors with osteoporosis were undiagnosed by their healthcare providers, and this was similar to the undiagnosed rate in the reference group (85.7%). Longitudinally, breast cancer survivors in this study did not demonstrate an accelerated rate of bone loss compared with the reference population. CONCLUSIONS: Associated with lower HT usage, postmenopausal survivors of breast cancer were more likely to have low BMD in comparison to other women of the same age; and many of these survivors with osteoporosis were undiagnosed.  相似文献   
4.
Context  Despite decades of use and considerable research, the role of estrogen alone in preventing chronic diseases in postmenopausal women remains uncertain. Objective  To assess the effects on major disease incidence rates of the most commonly used postmenopausal hormone therapy in the United States. Design, Setting, and Participants  A randomized, double-blind, placebo-controlled disease prevention trial (the estrogen-alone component of the Women's Health Initiative [WHI]) conducted in 40 US clinical centers beginning in 1993. Enrolled were 10 739 postmenopausal women, aged 50-79 years, with prior hysterectomy, including 23% of minority race/ethnicity. Intervention  Women were randomly assigned to receive either 0.625 mg/d of conjugated equine estrogen (CEE) or placebo. Main Outcome Measures  The primary outcome was coronary heart disease (CHD) incidence (nonfatal myocardial infarction or CHD death). Invasive breast cancer incidence was the primary safety outcome. A global index of risks and benefits, including these primary outcomes plus stroke, pulmonary embolism (PE), colorectal cancer, hip fracture, and deaths from other causes, was used for summarizing overall effects. Results  In February 2004, after reviewing data through November 30, 2003, the National Institutes of Health (NIH) decided to end the intervention phase of the trial early. Estimated hazard ratios (HRs) (95% confidence intervals [CIs]) for CEE vs placebo for the major clinical outcomes available through February 29, 2004 (average follow-up 6.8 years), were: CHD, 0.91 (0.75-1.12) with 376 cases; breast cancer, 0.77 (0.59-1.01) with 218 cases; stroke, 1.39 (1.10-1.77) with 276 cases; PE, 1.34 (0.87-2.06) with 85 cases; colorectal cancer, 1.08 (0.75-1.55) with 119 cases; and hip fracture, 0.61 (0.41-0.91) with 102 cases. Corresponding results for composite outcomes were: total cardiovascular disease, 1.12 (1.01-1.24); total cancer, 0.93 (0.81-1.07); total fractures, 0.70 (0.63-0.79); total mortality, 1.04 (0.88-1.22), and the global index, 1.01 (0.91-1.12). For the outcomes significantly affected by CEE, there was an absolute excess risk of 12 additional strokes per 10 000 person-years and an absolute risk reduction of 6 fewer hip fractures per 10 000 person-years. The estimated excess risk for all monitored events in the global index was a nonsignificant 2 events per 10 000 person-years. Conclusions  The use of CEE increases the risk of stroke, decreases the risk of hip fracture, and does not affect CHD incidence in postmenopausal women with prior hysterectomy over an average of 6.8 years. A possible reduction in breast cancer risk requires further investigation. The burden of incident disease events was equivalent in the CEE and placebo groups, indicating no overall benefit. Thus, CEE should not be recommended for chronic disease prevention in postmenopausal women.   相似文献   
5.
Depression among pregnant rural South African women undergoing HIV testing   总被引:1,自引:0,他引:1  
Rochat TJ  Richter LM  Doll HA  Buthelezi NP  Tomkins A  Stein A 《JAMA》2006,295(12):1376-1378
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6.
Calcium plus vitamin D (CaD) supplementation has a modest but significant effect on slowing loss of femoral bone mass and reducing risk of hip fractures in adherent postmenopausal women. The goal of this study was to determine if CaD supplementation influences hip structural parameters that are associated with fracture risk. We studied 1,970 postmenopausal women enrolled in the Women??s Health Initiative randomized controlled trial of CaD at one of three bone mineral density (BMD) clinical centers. Hip structural analysis software measured BMD and strength parameters on DXA scans at three regions: femoral narrow neck, intertrochanter, and shaft. Random effects models were used to test the average differences in hip BMD and geometry between intervention and placebo. There was greater preservation of hip BMD at the narrow neck with CaD relative to placebo across 6?years of intervention. CaD also altered the underlying cross-sectional geometry at the narrow neck in the direction of greater strength, with small increases in cross-sectional area and section modulus and a decrease in buckling ratio with CaD relative to placebo. While trends at both the intertrochanter and shaft regions were similar to those noted at the narrow neck, no significant intervention effects were evident. There was no significant interaction of CaD and age or baseline calcium levels for hip structural properties. CaD supplementation is associated with modest beneficial effects on hip structural features at the narrow neck, which may explain some of the benefit of CaD in reducing hip fracture risk.  相似文献   
7.
8.
OBJECTIVES: To prospectively examine the relationship between anemia and incident fractures of the hip, spine, and all skeletal sites in women from diverse racial and ethnic backgrounds enrolled in the Women's Health Initiative (WHI) Observational Study and Clinical Trials. DESIGN: Prospective cohort study. SETTING: Forty WHI clinical centers across the United States. PARTICIPANTS: Postmenopausal women (n=160,080), mean age 63.2 ± 7.2, were recruited and followed for an average of 7.8 years. MEASUREMENTS: Anemia was defined as hemoglobin levels at baseline less than 12 g/dL. All fractures were self‐reported. Trained physicians further confirmed hip fractures using medical records. RESULTS: Eight thousand seven hundred thirty‐nine of the participants (5.5%) were anemic. The age‐adjusted incidence rate of hip fractures per 10,000 person‐years was 21.4 in women with anemia and 15.0 in women without anemia; higher incidence rates for spine and all fractures were also observed in anemic women. After multiple covariates were included in the Cox proportional hazards models, significantly greater fracture risk associated with anemia still existed, as demonstrated by hazard ratios of fractures associated with anemia of 1.38 (95% confidence interval (CI)=1.13–1.68) for hip, 1.30 (95% CI=1.09–1.55) for spine, and 1.07 (95% CI=1.01–1.14) for all types. No significant racial or ethnic difference was found in these relationships. CONCLUSION: A significantly greater fracture risk was observed in multiethnic postmenopausal women with anemia. Given the high prevalence of anemia in the elderly population, it is important to better understand the relationship and mechanisms linking anemia to fracture risk.  相似文献   
9.
PURPOSE: We examined how an Alzheimer disease (AD) family history assessment as compared to a risk assessment incorporating the absence of a disease-associated susceptibility allele affected risk perception among adult children with a family history of AD. METHODS: The REVEAL study is a clinical trial in which adult children of patients with AD were randomized to receive a risk assessment based upon family history alone or family history plus apolipoprotein E (APOE) disclosure. In this analysis, two subsets of women were identified, each of whom received identical 29% lifetime risk estimates of developing AD. One group received a risk estimate that incorporated APOE epsilon4-negative genetic test results (Genotype Group, n = 30), whereas the other received a risk estimate based on family history and gender (Family History Group, n = 36). Six weeks after risk disclosure, we surveyed participants regarding the impact of the risk assessment on their perceptions of AD risk. RESULTS: 73% of the Genotype Group judged their risk to be lower compared to 25% of the Family History Group (P < 0.0001). 67% of the Genotype Group reported lower anxiety about AD, versus 26% of the Family History Group (P < 0.01). 80% of the Genotype Group indicated that the risk information had a positive impact, versus 36% of the Family History Group (P < 0.001). The Genotype Group was less likely to believe that they would develop AD (13% vs. 36%, P < 0.05) and was more likely to report that the risk assessment removed uncertainty about their chances of developing AD (63% vs. 9%, P < 0.0001). CONCLUSIONS: These data suggest that risk estimates incorporating negative genetic test results affect perceptions of disease susceptibility more strongly than identical estimates based on family history alone.  相似文献   
10.
OBJECTIVE: The purpose of this study is to examine the validity of, and factors associated with, the accuracy of self-report (participant-report and proxy-report) for fractures. DESIGN: Study participants were from the Women's Health Initiative Clinical Trial and Observational Study cohorts. All women were postmenopausal; populations included American Indian, Asian/Pacific Islander, black, Hispanic, and non-Hispanic white. The average length of follow-up was 4.3 years. Self-reported fractures were adjudicated by reviewing medical records. The first adjudicated self-report of fractures for each participant was included in the analysis (n = 6,652). RESULTS: We found substantial variations in validity of self-report by the fracture site. Agreements between self-reports for single-site fractures and medical records were high for hip (78%) and forearm/wrist (81%) but relatively lower for clinical spine fractures (51%). The average confirmation rate for all single-site fractures was 71%. Misidentification of fracture sites by participants or proxy-reporters seemed to be a cause of unconfirmed self-reports. Higher confirmation rates were observed in participant-reports than in proxy-reports. Results of the multivariate analysis indicated that multiple factors, such as ethnicity, a history of osteoporosis or fractures, body mass index, years since menopause, smoking status, and number of falls in the past year were significantly (P < 0.05) related to the validity of self-report. CONCLUSION: The validity of self-reports for fracture varies by fracture sites and many other factors. The assessed validity in this study is likely conservative because some of the unconfirmed self-reports may be due to poor medical record systems. The validity of self-reports for hip and forearm/wrist fractures is high in this study, supporting their use in epidemiological studies among postmenopausal women.  相似文献   
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