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121.
Powell-Wiley TM Ayers CR Banks-Richard K Berry JD Khera A Lakoski SG McGuire DK de Lemos JA Das SR 《Obesity (Silver Spring, Md.)》2012,20(4):849-855
Clinician counseling is a catalyst for lifestyle modification in obesity. Unfortunately, clinicians do not appropriately counsel all obese patients about lifestyle modification. The extent of disparities in clinician counseling is not well understood. Obese participants (BMI ≥30 kg/m2, N = 2097) in the Dallas Heart Study (DHS), a probability‐based sample of Dallas County residents ages 18–65, were surveyed regarding health‐care utilization and lifestyle counseling over the year prior to DHS enrollment. Health‐care utilization and counseling were compared between obese participants across three categories based on the presence of 0, 1, or 2+ of the following cardiovascular (CV) risk factors: hypertension, hypercholesterolemia, or diabetes. Logistic regression modeling was used to determine likelihood of counseling in those with 0 vs. 1+ CV risk factors, stratified by race, adjusting for age, sex, insurance status, and education. Among obese subjects who sought medical care, those with 0 CV risk factors, compared to those with 1 or 2+ CV risk factors, were less likely to report counseling about losing weight (41% vs. 67% vs. 87%, P trend <0.001), dietary changes (44% vs. 71% vs. 85%, P trend <0.001), and physical activity (46% vs. 71% vs. 86%, P trend <0.001). Blacks and Hispanics without CV risk factors had a lower odds of receiving counseling than whites without risk factors on weight loss (adjusted odds ratio (OR), 95% confidence interval (CI) for nonwhites 0.19, [0.13–0.28], whites 0.48, [0.26–0.87]); dietary changes (nonwhites 0.19, [0.13–0.27], whites 0.37, [0.21–0.64]); and physical activity (nonwhites 0.22, [0.16–0.32], whites 0.32, [0.18–0.57]). Lifestyle counseling rates by clinicians are suboptimal among obese patients without CV risk factors, especially blacks and Hispanics. Systematic education about and application of lifestyle interventions could capitalize on opportunities for primary CV risk prevention. 相似文献
122.
Nair MG Guild KJ Du Y Zaph C Yancopoulos GD Valenzuela DM Murphy A Stevens S Karow M Artis D 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(7):4709-4715
The secreted goblet cell-derived protein resistin-like molecule beta (RELMbeta) has been implicated in divergent functions, including a direct effector function against parasitic helminths and a pathogenic function in promoting inflammation in models of colitis and ileitis. However, whether RELMbeta influences CD4(+) T cell responses in the intestine is unknown. Using a natural model of intestinal inflammation induced by chronic infection with gastrointestinal helminth Trichuris muris, we identify dual functions for RELMbeta in augmenting CD4(+) Th1 cell responses and promoting infection-induced intestinal inflammation. Following exposure to low-dose Trichuris, wild-type C57BL/6 mice exhibit persistent infection associated with robust IFN-gamma production and intestinal inflammation. In contrast, infected RELMbeta(-/-) mice exhibited a significantly reduced expression of parasite-specific CD4(+) T cell-derived IFN-gamma and TNF-alpha and failed to develop Trichuris-induced intestinal inflammation. In in vitro T cell differentiation assays, recombinant RELMbeta activated macrophages to express MHC class II and secrete IL-12/23p40 and enhanced their ability to mediate Ag-specific IFN-gamma expression in CD4(+) T cells. Taken together, these data suggest that goblet cell-macrophage cross-talk, mediated in part by RELMbeta, can promote adaptive CD4(+) T cell responses and chronic inflammation following intestinal helminth infection. 相似文献
123.
Polyethylene glycol (PEG; 2000 MW, 30% by volume) has been shown to mechanically repair damaged cellular membranes and reduce
secondary axotomy after traumatic brain and spinal cord injury (TBI and SCI respectively). This repair is achieved following
spontaneous reassembly of cell membranes made possible by the action of targeted hydrophilic polymers which first seal the
compromised portion of the plasmalemma, and secondarily, allow the lipidic core of the compromised membranes to resolve into
each other. Here we compared PEG-treated to untreated rats using a computer-managed open-field behavioral test subsequent
to a standardized brain injury. Animals were evaluated after a 2-, 4-, and 6-hour delay in treatment after TBI. Treated animals
receive a single subcutaneous injection of PEG. When treated within 2 hours of the injury, injured PEG-treated rats showed
statistically significant improvement in their exploratory behavior recorded in the activity box when compared to untreated
but brain-injured controls. A delay of 4 hours reduced this level of achievement, but a statistically significant improvement
due to PEG injection was still clearly evident in most outcome measures compared at the various evaluation times. A further
delay of 2 more hours, however, eradicated the beneficial effects of PEG injection as revealed using this behavioral assessment.
Thus, there appears to be a critical window of time in which PEG administration after TBI can provide neuroprotection resulting
in an enhanced functional recovery. As is often seen in clinically applied acute treatments for trauma, the earlier the intervention
can be applied, the better the outcome. 相似文献
124.
Turning On and Off with Excitation: The Role of Spike-Timing Asynchrony and Synchrony in Sustained Neural Activity 总被引:4,自引:0,他引:4
Boris S. Gutkin Carlo R. Laing Carol. L. Colby Carson C. Chow G. Bard Ermentrout 《Journal of computational neuroscience》2001,11(2):121-134
Delay-related sustained activity in the prefrontal cortex of primates, a neurological analogue of working memory, has been proposed to arise from synaptic interactions in local cortical circuits. The implication is that memories are coded by spatially localized foci of sustained activity. We investigate the mechanisms by which sustained foci are initiated, maintained, and extinguished by excitation in networks of Hodgkin-Huxley neurons coupled with biophysical spatially structured synaptic connections. For networks with a balance between excitation and inhibition, a localized transient stimulus robustly initiates a localized focus of activity. The activity is then maintained by recurrent excitatory AMPA-like synapses. We find that to maintain the focus, the firing must be asynchronous. Consequently, inducing transient synchrony through an excitatory stimulus extinguishes the sustained activity. Such a monosynaptic excitatory turn-off mechanism is compatible with the working memory being wiped clean by an efferent copy of the motor command. The activity that codes working memories may be structured so that the motor command is both the read-out and a direct clearing signal. We show examples of data that is compatible with our theory. 相似文献
125.
Mathematical simulation and experimental measurement of dissolved O2 were performed for extended (up to 8 h) shear testing of Daucus carota (carrot) cell cultures in a conventional Couette viscometer (0.625 mm annulus). The results suggest O2 depletion below critical levels for cell growth may occur. A novel design modification incorporating an O2-permeable silicone-layer spun cast on a porous ceramic bowl was devised. It significantly improved oxygenation of the cell cultures, keeping dissolved O2 near saturation. 相似文献
126.
Nitrogen fixation mutants of Medicago truncatula fail to support plant and bacterial symbiotic gene expression 下载免费PDF全文
The Rhizobium-legume symbiosis culminates in the exchange of nutrients in the root nodule. Bacteria within the nodule reduce molecular nitrogen for plant use and plants provide bacteria with carbon-containing compounds. Following the initial signaling events that lead to plant infection, little is known about the plant requirements for establishment and maintenance of the symbiosis. We screened 44,000 M2 plants from fast neutron-irradiated Medicago truncatula seeds and isolated eight independent mutant lines that are defective in nitrogen fixation. The eight mutants are monogenic and represent seven complementation groups. To monitor bacterial status in mutant nodules, we assayed Sinorhizobium meliloti symbiosis gene promoters (nodF, exoY, bacA, and nifH) in the defective in nitrogen fixation mutants. Additionally, we used an Affymetrix oligonucleotide microarray to monitor gene expression changes in wild-type and three mutant plants during the nodulation process. These analyses suggest the mutants can be separated into three classes: one class that supports little to no nitrogen fixation and minimal bacterial expression of nifH; another class that supports no nitrogen fixation and minimal bacterial expression of nodF, bacA, and nifH; and a final class that supports low levels of both nitrogen fixation and bacterial nifH expression. 相似文献
127.
Economic Botany - Crop genetic diversity is important, but may be lost due to intentional or non-intentional selection processes. Jackfruit (Artocarpus heterophyllus) is the national fruit of... 相似文献
128.
Lei Chen Haley J. Abel Indraniel Das David E. Larson Liron Ganel Krishna L. Kanchi Allison A. Regier Erica P. Young Chul Joo Kang Alexandra J. Scott Colby Chiang Xinxin Wang Shuangjia Lu Ryan Christ Susan K. Service Charleston W.K. Chiang Aki S. Havulinna Johanna Kuusisto Ira M. Hall 《American journal of human genetics》2021,108(4):583-596
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