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951.
The International Journal of Life Cycle Assessment - Global demand for construction materials has grown exponentially in the last century, contributing to climate change and detrimental impacts on...  相似文献   
952.
Two new species of Hisonotus are described from the rio Paraná-Paraguay basin in Brazil. The most remarkable features of the new species are the odontodes forming longitudinally aligned rows (one odontode after the other, but not necessarily forming parallel series) on the head and trunk (vs. odontodes not forming longitudinally aligned rows), a pair of rostral plates at the tip of the snout (vs. a single rostral plate), the functional v-shaped spinelet (vs. spinelet non-functional, square-shaped, or absent). These features suggest close phylogenetic relationships with Hisonotus bockmanni, H. insperatus, H. luteofrenatus and H. piracanjuba. Additionally, both new species are distinguished from their congeners by characters related to head length and depth, orbital diameter, suborbital depth, caudal peduncle depth, pectoral-fin spine length, snout length and counts of teeth. Hisonotus paresi sp. n. further differs from its congeners by having contrasting dark geometric spots on the anterodorsal region of the body, a character lacking in H. oliveirai sp. n. The variation in number and shape of the rostral plate, posterior rostrum plates, infraorbitals and the preopercle in both new species and in H. insperatus are discussed.  相似文献   
953.
With increased polar anthropogenic activity, such as from the oil and gas industry, there are growing concerns about how Arctic species will be affected. Knowledge of species’ sensory abilities, such as auditory sensitivities, can be used to mitigate the effects of such activities. Herein, behavioral audiograms of two captive adult Arctic foxes (Vulpes lagopus) were measured using a yes/no paradigm and descending staircase method of signal presentation. Both foxes displayed a typical mammalian U-shaped audiometric curve, with a functional hearing range of 125 Hz–16 kHz (sensitivity ≤ 60 dB re: 20 μPa) and average peak sensitivity of 24 dB re: 20 μPa at 4 kHz. The foxes had a lower frequency range and sensitivity than would be expected when compared to previous audiograms of domestic dogs (Canis familiaris) and other carnivores. These differences indicate Arctic foxes (V. lagopus) may have a lower frequency range than previously expected, which was similar to the only other fox species tested to date, kit foxes (Vulpes macrotis). Alternatively, differences may be due to testing constraints, such as masking of test signals by ambient noise and/or an unintentionally trained conservative response bias, which most likely resulted in underestimated hearing curves. While results of this study should be interpreted with caution due to its limitations, findings indicate that foxes have a narrower frequency range than formerly presumed. Anthropogenic activities near fox habitats can mitigate their impacts by reducing noise at frequencies within the functional hearing range and peak sensitivities of this species.  相似文献   
954.
Vitamin D plays an increasingly recognized role in the innate and adaptive immune response to infection. Based on demonstrated roles in up-regulating innate immunity, decreasing inflammation, and reducing the severity of disease in illnesses such as tuberculosis and influenza, we hypothesized that poor vitamin D status would be associated with severe malaria. We measured 25-hydroxyvitamin D [25(OH)D] by immunoassay in a sample of Ugandan children aged 18 months –12 years with severe malaria (cerebral malaria or severe malarial anemia, n = 40) and in healthy community children (n = 20). Ninety-five percent of children with severe malaria (n = 38) and 80% of control children (n = 16) were vitamin D-insufficient [plasma 25(OH)D <30 ng/mL]. Mean plasma 25(OH)D levels were significantly lower in children with severe malaria than in community children (21.2 vs. 25.3 ng/mL, p = 0.03). Logistic regression revealed that for every 1 ng/mL increase in plasma 25(OH)D, the odds of having severe malaria declined by 9% [OR = 0.91 (95% CI: 0.84, 1.0)]. These preliminary results suggest that vitamin D insufficiency may play a role in the development of severe malaria. Further prospective studies in larger cohorts are indicated to confirm the relationship of vitamin D levels to severity of malaria infection and to investigate causality.  相似文献   
955.

Objective

To generate maps reflecting the intersection of community-based Voluntary Counseling and Testing (VCT) delivery points with facility-based HIV program demographic information collected at the district level in three districts (Ile, Maganja da Costa and Chinde) of Zambézia Province, Mozambique; in order to guide planning decisions about antiretroviral therapy (ART) program expansion.

Methods

Program information was harvested from two separate open source databases maintained for community-based VCT and facility-based HIV care and treatment monitoring from October 2011 to September 2012. Maps were created using ArcGIS 10.1. Travel distance by foot within a 10 km radius is generally considered a tolerable distance in Mozambique for purposes of adherence and retention planning.

Results

Community-based VCT activities in each of three districts were clustered within geographic proximity to clinics providing ART, within communities with easier transportation access, and/or near the homes of VCT volunteers. Community HIV testing results yielded HIV seropositivity rates in some regions that were incongruent with the Ministry of Health’s estimates for the entire district (2–13% vs. 2% in Ile, 2–54% vs. 11.5% in Maganja da Costa, and 23–43% vs. 14.4% in Chinde). All 3 districts revealed gaps in regional disbursement of community-based VCT activities as well as access to clinics offering ART.

Conclusions

Use of geospatial mapping in the context of program planning and monitoring allowed for characterizing the location and size of each district’s HIV population. In extremely resource limited and logistically challenging settings, maps are valuable tools for informing evidence-based decisions in planning program expansion, including ART.  相似文献   
956.

Background

Poverty is a multidimensional phenomenon and unidimensional measurements have proven inadequate to the challenge of assessing its dynamics. Dynamics between poverty and public health intervention is among the most difficult yet important problems faced in development. We sought to demonstrate how multidimensional poverty measures can be utilized in the evaluation of public health interventions; and to create geospatial maps of poverty deprivation to aid implementers in prioritizing program planning.

Methods

Survey teams interviewed a representative sample of 3,749 female heads of household in 259 enumeration areas across Zambézia in August-September 2010. We estimated a multidimensional poverty index, which can be disaggregated into context-specific indicators. We produced an MPI comprised of 3 dimensions and 11 weighted indicators selected from the survey. Households were identified as “poor” if were deprived in >33% of indicators. Our MPI is an adjusted headcount, calculated by multiplying the proportion identified as poor (headcount) and the poverty gap (average deprivation). Geospatial visualizations of poverty deprivation were created as a contextual baseline for future evaluation.

Results

In our rural (96%) and urban (4%) interviewees, the 33% deprivation cut-off suggested 58.2% of households were poor (29.3% of urban vs. 59.5% of rural). Among the poor, households experienced an average deprivation of 46%; thus the MPI/adjusted headcount is 0.27 ( = 0.58×0.46). Of households where a local language was the primary language, 58.6% were considered poor versus Portuguese-speaking households where 73.5% were considered non-poor. Living standard is the dominant deprivation, followed by health, and then education.

Conclusions

Multidimensional poverty measurement can be integrated into program design for public health interventions, and geospatial visualization helps examine the impact of intervention deployment within the context of distinct poverty conditions. Both permit program implementers to focus resources and critically explore linkages between poverty and its social determinants, thus deriving useful findings for evidence-based planning.  相似文献   
957.
Intestinal resections are frequently required for treatment of diseases involving the gastrointestinal tract, with Crohn’s disease and colon cancer being two common examples. Despite the frequency of these procedures, a significant knowledge gap remains in describing the inherent effects of intestinal resection on host physiology and disease pathophysiology. This article provides detailed instructions for an ileocolic resection with primary end-to-end anastomosis in mice, as well as essential aspects of peri-operative care to maximize post-operative success. When followed closely, this procedure yields a 95% long-term survival rate, no failure to thrive, and minimizes post-operative complications of bowel obstruction and anastomotic leak. The technical challenges of performing the procedure in mice are a barrier to its wide spread use in research. The skills described in this article can be acquired without previous surgical experience. Once mastered, the murine ileocolic resection procedure will provide a reproducible tool for studying the effects of intestinal resection in models of human disease.  相似文献   
958.
Humans are both similar and diverse in such a vast number of dimensions that for human geneticists and social scientists to decide which of these dimensions is a worthy focus of empirical investigation is a formidable challenge. For geneticists, one vital question, of course, revolves around hypothesizing which kind of social diversity might illuminate genetic variation—and vice versa (i.e., what genetic variation illuminates human social diversity). For example, are there health outcomes that can be best explained by genetic variation—or for social scientists, are health outcomes mainly a function of the social diversity of lifestyles and social circumstances of a given population? Indeed, what is a “population,” how is it bounded, and are those boundaries most appropriate or relevant for human genetic research, be they national borders, religious affiliation, ethnic or racial identification, or language group, to name but a few? For social scientists, the matter of what constitutes the relevant borders of a population is equally complex, and the answer is demarcated by the goal of the research project. Although race and caste are categories deployed in both human genetics and social science, the social meaning of race and caste as pathways to employment, health, or education demonstrably overwhelms the analytic and explanatory power of genetic markers of difference between human aggregates.Two contradictory magnetic poles pull medical research on humans in opposite directions, producing a tension that will never be resolved. On the one hand, there is a universalizing impulse—based on a legitimate assumption that human bodies are sufficiently similar that vaccines, catheters, pasteurizing processes, and tranquilizers that work in one population will work in others. On the other hand, and unless and until research protocols establish and confirm specific similarities across populations, there is sufficient human variation that targeting medicines for specific populations can be a legitimate—even vital—empirically driven task. The theoretical question, of course, is why a particular population or subpopulation is to be so targeted? Because of folk theories about different groups’ biological difference, or because of their social and political standing? Age, gender, and race leap to the forefront. The history of research on ailments as disparate as breast and prostate cancer (Rothenberg 1997; Wailoo 2011), heart disease (Cooper et al. 2005), and syphilis (Jones 1981; Reverby 2009) provides strong evidence that the answer is not either/or but both. So, on what grounds do we choose one strategy over the other?And it is precisely on this point that Steven Epstein (2007) raises the most fundamental question:
Out of all the ways by which people differ from one another, why should it be assumed that sex and gender, race and ethnicity, and age are the attributes of identity that are most medically meaningful? Why these markers of identity and not others? (Epstein 2007, p. 10)
The answer is profoundly social and political, economic, and cultural. The United States is the only country in the world that, as public health policy, does not operate on the assumption of the single standard human.Moreover, by highlighting certain categories, there is the unassailable truth that other categories are thereby ignored. But more to the theoretical point, because each of the categories noted above has a potential or real biological base in either scientific or common sense understandings (Schutz 1962), when scientists report findings indicating differences, the danger is that these findings can seductively divert policymakers from seeking alternative interventions that could better address health disparities (Krieger 2011).The goal of Epstein’s monograph was to (a) better understand how ways of thinking about differences in human populations paved the way to try to “improve medical research by making it inclusive,” and (b) explain how and why the strategies of exclusiveness got institutionalized:
Academic researchers receiving federal funds, and pharmaceutical manufacturers hoping to win regulatory approval for their company''s products, are now enjoined to include women, racial and ethnic minorities, children, and the elderly as research subjects in many forms of clinical research … and question the presumption that findings derived from the study of any single group, such as middle-aged white men, might be generalized to other populations. (Epstein 2007, p. 5)
This shift has occurred only in the last two and a half decades, beginning with regulations that were developed first in 1986. Once again, it is important to restate the relatively unique feature of this development as it applies mainly to the United States (Epstein 2007, p. 7). The rest of the world has continued to act on the presupposition of the standard human, at least until now. As we shall see, that is about to change.  相似文献   
959.
The evolution of resistance to antimicrobial chemotherapy is a major and growing cause of human mortality and morbidity. Comparatively little attention has been paid to how different patient treatment strategies shape the evolution of resistance. In particular, it is not clear whether treating individual patients aggressively with high drug dosages and long treatment durations, or moderately with low dosages and short durations can better prevent the evolution and spread of drug resistance. Here, we summarize the very limited available empirical evidence across different pathogens and provide a conceptual framework describing the information required to effectively manage drug pressure to minimize resistance evolution.  相似文献   
960.
During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia–NCAMs) modulate cell–cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia–NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb’s to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell–cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders.  相似文献   
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