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991.
Meredith F. Small 《American journal of physical anthropology》1997,103(4):573-574
Edited by John E. Fa and Donald G. Lindburg. New York: Cambridge University Press. 1996. 597 pp. ISBN 0-521-41680-0. $125.00 (cloth). 相似文献
992.
Meredith Vanstone Shipra Taneja Anuoluwa Popoola Janelle Panday Devon Greyson Robin Lennox Sarah D. McDonald 《CMAJ》2021,193(50):E1906
Background:Cannabis use among pregnant and lactating people is increasing, despite clinical evidence showing that cannabis use may be associated with low birth weight and childhood developmental deficits. Our objective was to understand why pregnant and lactating people use cannabis and how these motivations change across perinatal stages.Methods:Using qualitative, constructivist grounded theory methodology, we conducted telephone and virtual interviews with 52 individuals from across Canada. We selected participants using maximum variation and theoretical sampling. They were eligible if they had been pregnant or lactating within the past year and had decided to continue, cease or decrease their cannabis use during the perinatal period.Results:We identified 3 categories of reasons that people use cannabis during pregnancy and lactation: sensation-seeking for fun and enjoyment; symptom management of chronic conditions and conditions related to pregnancy; and coping with the unpleasant, but nonpathologized, experiences of life. Before pregnancy, participants endorsed reasons for using cannabis in these 3 categories in similar proportions, with many offering multiple reasons for use. During pregnancy, reasons for use shifted primarily to symptom management. During lactation, reasons returned to resemble those expressed before pregnancy.Interpretation:In this study, we showed that pregnant and lactating people use cannabis for many reasons, particularly for symptom management. Reasons for cannabis use changed across reproductive stages. The dynamic nature of the reasons for use across stages speaks to participant perception of benefits and risks, and perhaps a desire to cast cannabis use during pregnancy as therapeutic because of perceived stigma.Cannabis use by pregnant and lactating people is increasing, though it is difficult to establish the prevalence of cannabis use in pregnancy. Reported prevalence varies from 2% to 36%, depending on the methodology used to detect use, the population studied and the definition of use.1–12 Pregnant people have reported using cannabis to manage pregnancy-related conditions (e.g., nausea, weight gain, sleep difficulty)13–19 and pre-existing conditions (e.g., mental health, insomnia, chronic pain),13,14,18 as well as to improve mood, mental, physical and spiritual well-being,16,18 provide pleasure and manage stress.13–16 Recent systematic reviews have not found empirical data on reasons for cannabis use during lactation.20,21Evidence is still emerging about clinical outcomes related to cannabis use during pregnancy and lactation, and well-controlled studies are lacking.22–24 The available evidence is limited by reliance on self-reported data about dose, composition and timing of exposure, the changing nature of tetrahydrocannabinol levels in cannabis over time, and a lack of studies that control for known confounders such as polysubstance and tobacco use.25–31 The available evidence does suggest that cannabis use during pregnancy may be associated with complications such as low birth weight, childhood neurodevelopmental outcomes and preterm birth.22–24,32,33 Very few studies have analyzed the outcomes associated with cannabis exposure through breastmilk, with 1 study suggesting decreased infant motor development and another showing no effects on developmental outcomes.34–36 Given the potential harms identified, and in the absence of high-quality evidence available to guide practice, most clinical guidelines recommend abstinence from cannabis during pregnancy and lactation.37–39People who perceive benefits from cannabis may wish to or may be motivated to continue using it through pregnancy and lactation, however. Counselling that explores the reasons patients are considering cannabis use and suggests related alternatives or harm reduction strategies has been identified as a helpful strategy to minimize potential harm.13,40,41,42 Such an approach requires that clinicians understand the motivations to use cannabis before pregnancy, during pregnancy and during lactation. We sought to explore why people use cannabis during pregnancy and lactation. 相似文献
993.
Urszula Dougherty Reba Mustafi Hongyan Zhu Xiaorong Zhu Dilip Deb Stephen C. Meredith Fatma Ayaloglu-Butun Michelle Fletcher Arantxa Sanchez Joel Pekow Zifeng Deng Nader Amini Vani J Konda Vijaya L. Rao Atsushi Sakuraba Akushika Kwesi Sonia S Kupfer Alessandro Fichera Loren Joseph John Hart Fang He Tong-Chuan He Diana West-Szymanski Yan Chun Li Marc Bissonnette 《Epigenetics》2021,16(12):1317
994.
Attachment relationships between animals are often studied by separating a pair of individuals and recording their subsequent behavior. Studies of non‐human primates have shown that separation results in changes that are indicative of both psychological and physiological stress. Similar results have been found in several non‐primate species with differing social structures. This study examined the behavior of two female giraffe at Zoo Atlanta after the removal of the resident male. Data were collected on the giraffe before and after separation, using an instantaneous scan sampling technique to record levels of activity, social behaviors, solitary behaviors, proximity, and habitat utilization. After the removal of the resident male, both giraffe exhibited increased levels of activity, stereotypical behavior, contact behavior (particularly neck‐rubbing), and decreased habitat utilization. These results are similar to those found in earlier primate separation studies, supporting the hypothesis that complex social structure is not necessary for the formation of social attachments. Because social separation is often accompanied by behavioral and physiological indications of stress, an understanding of the variables involved in a species' response to separation is vital to the promotion of the psychological and physical well‐being of captive animals. Zoo Biol 19:41–51, 2000. © 2000 Wiley‐Liss, Inc. 相似文献
995.
Exploring methods for rapid assessment of woody vegetation in the Batemi Valley, North-central Tanzania 总被引:1,自引:0,他引:1
Conservation of local biological resources in remote areas requires efficient data and collection methods. This paper describes part of a local conservation initiative in Northern Tanzania in which an indigenous conservation group enlisted the support of outside scientists to explore means of preparing baseline ecological reports. Two factors are seen as important: one is local use of ecological resources and the other is local availability. This paper focuses on the second of these and considers woody species. A variety of ecological field methods, statistical analysis and remote sensing and mapping techniques are used to generate baseline ecological inventories. The fieldwork identified 101 woody species, representing 54 genera and 37 families in the Batemi area. There are three main vegetation types: Vangueria apiculata-Ficus sycomorus-Trichilia emetica type; Croton dictygamous-Euphorbia tirucalli-Grewia bicolor type; and Acacia tortilis-Balanites aegyptica-Euphorbia candelabrum type. The Landsat TM map identified four main land-cover classes: (1) bushland and woodland thicket, (2) woodland (3) wooded grassland, and (4) grassland with scattered trees, which includes agricultural areas and villages. The combination of these data and methods can be useful for conservation planning and long-term monitoring, but it is clear that ground-level local assessment is necessary to detect subtleties of human-environment interaction that are required for conservation planning. 相似文献
996.
The Ability of Herpes Simplex Virus Type 1 Immediate-Early Protein Vmw110 To Bind to a Ubiquitin-Specific Protease Contributes to Its Roles in the Activation of Gene Expression and Stimulation of Virus Replication 总被引:16,自引:8,他引:8 下载免费PDF全文
Herpes simplex virus type 1 immediate-early protein Vmw110 stimulates the onset of virus infection and is required for efficient reactivation from latency. In transfection assays, Vmw110 is a potent activator of gene expression, but its mode of action has yet to be determined. Previous work has shown that Vmw110 localizes to specific intranuclear structures known as ND10, PML bodies, or PODs and causes the disruption of these domains. The ability of Vmw110 to disrupt ND10 correlates with its biological activities in infected and transfected cells. It has also been found that Vmw110 binds strongly and specifically to a ubiquitin-specific protease known as HAUSP, itself a component of a subset of ND10. In this study we have investigated the role of HAUSP in Vmw110 activity; single amino acid residues of Vmw110 required for the interaction were identified, and the effects of mutation of these residues in infected and transfected cells were then assayed. The results indicate that the ability to bind to HAUSP contributes to the functional activities of Vmw110. 相似文献
997.
A Cell Signal Pathway Involving Laminin-5, α3β1 Integrin, and Mitogen-activated Protein Kinase Can Regulate Epithelial Cell Proliferation 下载免费PDF全文
Meredith Gonzales Keith Haan Scott E. Baker Mark Fitchmun Ivan Todorov Sigmund Weitzman Jonathan C.R. Jones 《Molecular biology of the cell》1999,10(2):259-270
Laminin-5 (LN5) is a matrix component of epithelial tissue basement membranes and plays an important role in the initiation and maintenance of epithelial cell anchorage to the underlying connective tissue. Here we show that two distinct LN5 function-inhibitory antibodies, both of which bind the globular domain of the α3 subunit, inhibit proliferation of epithelial cells. These same antibodies also induce a decrease in mitogen-activated protein kinase activity. Inhibition of proliferation by the function-perturbing LN5 antibodies is reversed upon removal of the antibodies and can be overcome by providing the antibody-treated cells with exogenous LN5 and rat tail collagen. Because epithelial cells use the integrin receptor α3β1 to interact with both LN5 and rat tail collagen, we next investigated the possibility that integrin α3β1 is involved in mediating the proliferative impact of LN5. Proliferation of human epithelial cells is significantly inhibited by a function-perturbing α3 integrin antibody. In addition, antibody activation of β1 integrin restores the proliferation of epithelial cells treated with LN5 function-perturbing antibodies. These data indicate that a complex comprising LN5 and α3β1 integrin is multifunctional and contributes not only to epithelial cell adhesion but also to the regulation of cell growth via a signaling pathway involving mitogen-activated protein kinase. We discuss our study in light of recent evidence that LN5 expression is up-regulated at the leading tips of tumors, where it may play a role in tumor cell proliferation. 相似文献
998.
Leszek Karczmarski Meredith Thornton Victor G. Cockcroft 《African Journal of Ecology》2000,38(1):86-90
This paper describes the pattern of daylight occurrence of humpback dolphins Sousa chinensis in Algoa Bay, the Eastern Cape, South Africa, between May 1991 and May 1994. Two indices, the Sighting Index (SI) and the Total Recorded Dolphin Presence (TRDP), were used to quantify the dolphins' daylight occurrence. Humpback dolphins display a clear pattern of daylight occurrence in Algoa Bay and can be seen mostly in the morning, and, to a lesser extent, in the evening. This pattern varies little between seasons (with possible exception for the evening hours), follows the time of the solar day, is not related to the tidal cycle and is probably governed by the diurnal cycles of dolphins' prey. 相似文献
999.
Large (200 mm3) slices of polyacrylamide gels crosslinked with N,N'-diallyltartardiamide which contain tritium-labeled protein are readily solubilized in periodic acid for liquid scintillation counting of radioactivity, but the apparent recovery of label never exceeds 82%. Extraction of the slices with two commercial solubilizers at 60 degrees C gave recoveries of 82-90% which were not improved by prolonged incubation. Treatment of the slices at ambient temperature with 1.0 ml of 2% sodium periodate for 30 min followed by the addition of 0.7 ml of aqueous tetrabutylammonium hydroxide (40% w/v) gives solutions which can be immediately counted at 35% efficiency with low background and with 100% recovery of tritiated protein 相似文献
1000.