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501.
Ben Van Calster Vanya Van Belle Yvonne Vergouwe Ewout W. Steyerberg 《Biometrical journal. Biometrische Zeitschrift》2012,54(5):674-685
In this paper, we focus on measures to evaluate discrimination of prediction models for ordinal outcomes. We review existing extensions of the dichotomous c‐index—which is equivalent to the area under the receiver operating characteristic (ROC) curve—suggest a new measure, and study their relationships. The volume under the ROC surface (VUS) scores sets of cases including one case from each outcome category. VUS considers sets as either correctly or incorrectly ordered by the model. All other existing measures assess pairs of cases. We propose an ordinal c‐index (ORC) that is set‐based but, contrary to VUS, scores sets more gradually by indicating the closeness of the model‐based ordering to the perfect ordering. As a result, the ORC does not decrease rapidly as the number of outcome categories increases. It turns out that the ORC can be rewritten as the average of pairwise c‐indexes. Hence, the ORC has both a set‐ and pair‐based interpretation. There are several relationships between the existing measures, leading to only two types of existing measures: a prevalence‐weighted average of pairwise c‐indexes and the VUS. Our suggested measure ORC positions itself in between as it is set‐based but turns out to equal an unweighted average of pairwise c‐indexes. The measures are demonstrated through a case study on the prediction of six‐month outcome after traumatic brain injury. In conclusion, the set‐based nature and graded scoring system make the ORC an attractive measure with a simple interpretation, together with its prevalence‐independence that is a natural property of a discrimination measure. 相似文献
502.
Jingxuan Quek Cheng Han Ng Ansel Shao Pin Tang Nicholas Chew Mark Chan Chin Meng Khoo Chen Poh Wei Yip Han Chin Phoebe Tay Grace Lim Darren Jun Hao Tan Wen Hui Lim Kai En Chan Margaret Teng Eunice Tan Nobuharu Tamaki Daniel Q. Huang Mohammad Shadab Siddiqui Mark D. Muthiah 《Endocrine practice》2022,28(7):667-672
ObjectiveThe recent introduction of the term metabolic associated fatty liver disease (MAFLD) sought to reclassify nonalcoholic fatty liver disease (NAFLD). MAFLD is thought to improve the encapsulation of metabolic dysregulation. However, recent evidence has found significant differences between MAFLD and NAFLD, and prevailing knowledge has largely arisen from studies on NAFLD. Hence, we conducted a meta-analysis and systematic review of the outcomes associated with MAFLD.MethodsMEDLINE and Embase databases were searched for articles relating to outcomes in MAFLD. Analysis was conducted in random effects with hazard ratios (HRs) to account for longitudinal risk assessment of mortality and systemic complications.ResultsA total of 554 articles were identified, of which 17 articles were included. MAFLD resulted in an increase in the overall mortality (HR, 1.24; confidence interval [CI], 1.13-1.34), cancer-related mortality (HR, 1.27; CI, 1.01-1.54), and cardiovascular disease mortality (HR, 1.28, 1.03-1.53; P = .04) compared with non-MAFLD. MAFLD also increases the risk of cardiovascular events (HR, 1.49; CI, 1.34-1.64; P < .01), stroke (HR, 1.55; CI, 1.37-1.73; P < .01), and chronic kidney disease (HR, 1.53; CI, 1.38-1.68). The presence of MAFLD was also associated with an increased risk of heart failure, obstructive sleep apnea, and malignancy.ConclusionMAFLD can significantly elevate the risk of systemic diseases and mortality. The care of MAFLD thus requires interdisciplinary collaboration, and future clinical trials conducted on MAFLD should aim to reduce the incidence of end-organ damage aside from improving liver histology. 相似文献
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505.
Birth order has been examined over a wide variety of dimensions in the context of modern populations. A consistent message
has been that it is better to be born first. The analysis of birth order in this paper is different in several ways from other
investigations into birth order effects. First, we examine the effect of birth order in an egalitarian, small-scale, kin-based
society, which has not been done before. Second, we use a different outcome measure, fertility, rather than outcome measures
of social, psychological, or economic success. We find, third, that being born late in an egalitarian, technologically simple
society rather than being born early has a positive outcome on fertility, and fourth, that number of older siblings and sibling
set size are even stronger predictors of fertility, especially for males.
Patricia Draper is a professor in the Department of Anthropology at the University of Nebraska. Her research interests are
in cross-cultural human development, evolutionary theory, hunter-gatherer society, and comparative family organization.
Raymond Hames is also a professor in the Department of Anthropology at the University of Nebraska. His research interests
are in behavioral and evolutionary ecology, exchange systems, and tropical forest peoples. 相似文献
506.
《Reproductive biology》2022,22(4):100703
We previously explored the associations between β-hCG on the 14th day post–embryo transfer (ET) and reproductive outcomes and established a series of cutoff values to predict different outcomes. The aim of this study was to explore the parameters associated with β-hCG levels and establish β-hCG cutoff values in women undergoing single blastocyst transfer. The patients were transferred with either fresh or frozen-thawed blastocysts. Serum β-hCG levels were compared among different groups. Cutoff values of β-hCG were established and applied to divide the patients into different groups, among which the β-hCG groups were compared. Develop day negatively affected β-HCG levels in those who were pregnant or gave live birth (P < 0.001, 0.008). Inner cell mass significantly affected β-hCG levels in women who were pregnant or gave live birth (P = 0.013, 0.044). Trophectoderm significantly affected β-hCG levels in women with most reproductive outcomes, except biochemical pregnancy (BP) (P = 0.184). The cutoff values of β-hCG for predicting positive outcomes were 194.1, 503.0, 1048.0, and 2590.5 mIU/L. BP rates and adverse pregnancy outcome rates were significantly lower in the higher β-hCG groups (P < 0.001). Shorter gestational age and lower birth weight and length (P = 0.005, 0.041, 0.003) were observed in the lowest-concentration β-hCG group. The application of a single β-hCG measurement was sufficient to predict reproductive outcome in women undergoing blastocyst transfer, under the full consideration of blastocyst parameters. However, the association between β-hCG and obstetric outcomes remains to be investigated and fully explained. 相似文献
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508.
Andrea B. Gorzitze 《Primates; journal of primatology》1996,37(1):75-78
Two births of wild proboscis monkeys took place during a 1991/1992 field study at Tanjung Puting National Park, Indonesia.
After conception, both females continued copulating with their group’s male. One of the births took place during the night,
the other during mid-morning. In the latter case, the infant was born unassisted while the members of the group watched the
birthing process. After parturition, the mother consumed the placenta. 相似文献
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