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71.
Malin C. Rivers Neil A. Brummitt Eimear Nic Lughadha Thomas R. Meagher 《Conservation Genetics》2011,12(5):1333-1344
The distribution of genetic diversity has potential to inform conservation efforts but is rarely incorporated when conservation
status is assigned to a species. These data can be beneficial to the conservation assessment process by providing information
on subpopulations, gene flow and effective population sizes, thus achieving more successful assessments. In order to obtain
a better understanding of the patterns of genetic variation and their relationship to conservation in the fragmented flora
of Madagascar, this study assessed genetic diversity among and within Delonix s.l. (Leguminosae) using AFLP markers. The genetic diversity of eight species of Delonix s.l. (covering 79 sample sites and 254 individuals) showed a range of values (25–61% for polymorphic loci, and 0.076–0.192 Shannon’s
Index). Results from an analysis of molecular variance (AMOVA) suggest that a majority of the genetic variance is attributed
to variation within species (87%), which is also supported by a principle coordinate analysis of genetic distances between
sites. The results were used to compare the genetic difference between species of different threat status and show that even
closely related species with the same IUCN threat status differ in their genetic structure, probably arising from differences
in life history traits, pollen and seed dispersal, and fragmentation. Species that are recently affected by habitat destruction
and fragmentation are likely to be at high potential risk of genetic erosion contributing to their ongoing decline. Thus,
genetic variation should be taken into consideration in conservation assessments, whenever possible, to provide accurate and
targeted conservation recommendations in order to achieve more successful conservation outcomes. 相似文献
72.
Gustavsson E Ek S Steen J Kristensson M Älgenäs C Uhlén M Wingren C Ottosson J Hober S Borrebaeck CA 《New biotechnology》2011,28(4):302-311
In the past decade, many initiatives were taken for the development of antibodies for proteome-wide studies, as well as characterisation and validation of clinically relevant disease biomarkers. Phage display offers many advantages compared to antibody generation by immunisation because it is an unlimited resource of affinity reagents without batch-to-batch variation and is also amendable for high throughput in contrast to conventional hybridoma technology. One of the major bottlenecks to proteome-wide binder selection is the limited supply of suitable target antigens representative of the human proteome. Here, we provide proof of principle of using easily accessible, cancer-associated protein epitope signature tags (PrESTs), routinely generated within the Human Protein Atlas project, as surrogate antigens for full-length proteins in phage selections for the retrieval of target-specific binders. These binders were subsequently tested in western blot, immunohistochemistry and protein microarray application to demonstrate their functionality. 相似文献
73.
Kiani A Nielsen MO Tauson AH Tygesen MP Husted SM Chwalibog A 《Archives of animal nutrition》2011,65(1):46-54
The objective of this study was to investigate the effects of foetal undernutrition on the metabolism in growing lambs. Seven-month-old lambs whose mothers had been fed either restrictively (RN; n = 14) or adequately (AN; n = 6) in late gestation were fasted for three days. One hour before fasting and after 48 h and 72 h fasting, changes in plasma concentrations of metabolites, i.e. glucose, nonesterified fatty acids (NEFA), 3-beta-hydroxybutyrate (BOHB) and urea as well as hormones, i.e. insulin, the insulin-like growth factor (IGF-I) and leptin, were determined. Blood glucose, NEFA, urea, insulin, IGF-I and leptin were not different between the two groups of lambs. Unexpectedly, at the end of the 3 d fasting, in spite of lower NEFA concentration (1.6 +/- 0.03 vs. 1.9 +/- 0.05 mM in Groups RN and AN, respectively), the BOHB concentration in RN lambs (0.94 +/- 0.02 mM) was significantly higher than that in AN lambs (0.78 +/- 0.04 mM). This higher rate of BOHB production might be interpreted as perturbations in ketone body metabolism potentially induced by undernutrition during foetal life. However, more investigations are necessary to clarify this interrelationship. 相似文献
74.
75.
BackgroundPrivacy legislation in most jurisdictions allows the disclosure of health data for secondary purposes without patient consent if it is de-identified. Some recent articles in the medical, legal, and computer science literature have argued that de-identification methods do not provide sufficient protection because they are easy to reverse. Should this be the case, it would have significant and important implications on how health information is disclosed, including: (a) potentially limiting its availability for secondary purposes such as research, and (b) resulting in more identifiable health information being disclosed. Our objectives in this systematic review were to: (a) characterize known re-identification attacks on health data and contrast that to re-identification attacks on other kinds of data, (b) compute the overall proportion of records that have been correctly re-identified in these attacks, and (c) assess whether these demonstrate weaknesses in current de-identification methods.ConclusionsThe current evidence shows a high re-identification rate but is dominated by small-scale studies on data that was not de-identified according to existing standards. This evidence is insufficient to draw conclusions about the efficacy of de-identification methods. 相似文献
76.
Antisecretory Factor (AF) is a protein that has been implicated in the suppression of intestinal hypersecretion and inflammation. Intestinal secretion and inflammation are partly under local and central neural control raising the possibility that AF might exert its action by modulating neural signaling. In the present study we have investigated whether AF can modulate central synaptic transmission. Evoked glutamatergic and GABAergic synaptic transmissions were investigated using extracellular recordings in the CA1 region of hippocampal slices from adult rats. AF (0.5 microg/ml) suppressed GABA(A)-mediated synaptic transmission by about 40% while having no effect on glutamatergic transmission. Per oral administration of cholera toxin as well as feeding of rats with a diet containing hydrothermally processed cereals, known to upregulate endogenous AF plasma activity, mimicked the effect of exogenously administered AF on hippocampal GABAergic transmission. Our results identify AF as a neuromodulator and further raise the possibility that the hippocampus and AF are involved in a gut-brain loop controlling intestinal secretion and inflammation. 相似文献
77.
Jochems C Islander U Erlandsson M Verdrengh M Ohlsson C Carlsten H 《Arthritis research & therapy》2005,7(4):R837-R843
Generalized osteoporosis in postmenopausal rheumatoid arthritis (RA) is caused both by estrogen deficiency and by the inflammatory
disease. The relative importance of each of these factors is unknown. The aim of this study was to establish a murine model
of osteoporosis in postmenopausal RA, and to evaluate the relative importance and mechanisms of menopause and arthritis-related
osteoporosis. To mimic postmenopausal RA, DBA/1 mice were ovariectomized, followed by the induction of type II collagen-induced
arthritis. After the mice had been killed, paws were collected for histology, one femur for bone mineral density (BMD) and
sera for analyses of markers of bone resorption (RatLaps; type I collagen cross-links, bone formation (osteocalcin) and cartilage
destruction (cartilage oligomeric matrix protein), and for the evaluation of antigen-specific and innate immune responsiveness.
Ovariectomized mice displayed more severe arthritis than sham-operated controls. At termination of the experiment, arthritic
control mice and non-arthritic ovariectomized mice displayed trabecular bone losses of 26% and 22%, respectively. Ovariectomized
mice with arthritis had as much as 58% decrease in trabecular BMD. Interestingly, cortical BMD was decreased by arthritis
but was not affected by hormonal status. In addition, markers of bone resorption and cartilage destruction were increased
in arthritic mice, whereas markers of bone formation were increased in ovariectomized mice. This study demonstrates that the
loss of endogenous estrogen and inflammation contribute additively and equally to osteoporosis in experimental postmenopausal
polyarthritis. Markers of bone remodeling and bone marrow lymphocyte phenotypes indicate different mechanisms for the development
of osteoporosis caused by ovariectomy and arthritis in this model. 相似文献
78.
Pettersen FO Torheim EA Dahm AE Aaberge IS Lind A Holm M Aandahl EM Sandset PM Taskén K Kvale D 《Journal of virology》2011,85(13):6557-6566
Chronic HIV infection is characterized by chronic immune activation and dysfunctional T cells with elevated intracellular cyclic AMP (cAMP), which inhibits the T cell activation capability. cAMP may be induced by prostaglandin E(2) following lipopolysaccharide (LPS)-induced upregulation of cyclooxygenase type 2 (COX-2) in monocytes due to the elevated LPS levels in patients with chronic HIV infection. This hypothesis was tested using celecoxib, a COX-2 inhibitor, for 12 weeks in HIV-infected patients without antiretroviral treatment in a prospective, open, randomized exploratory trial. Thirty-one patients were randomized in the trial; 27 completed the study, including 13 patients on celecoxib. Celecoxib reduced chronic immune activation in terms of CD38 density on CD8(+) T cells (-24%; P = 0.04), IgA levels (P = 0.04), and a combined score for inflammatory markers (P < 0.05). Celecoxib further reduced the inhibitory surface receptor programmed death 1 (PD-1) on CD8(+) T cells (P = 0.01), including PD-1 on the HIV Gag-specific subset (P = 0.02), enhanced the number of CD3(+) CD4(+) CD25(+) CD127(lo/-) Treg or activated cells (P = 0.02), and improved humoral memory recall responses to a T cell-dependent vaccine (P = 0.04). HIV RNA (P = 0.06) and D dimers (P = 0.07) tended to increase in the controls, whereas interleukin-6 (IL-6) possibly decreased in the treatment arm (P = 0.10). In conclusion, celecoxib downmodulated the immune activation related to clinical progression of chronic HIV infection and improved T cell-dependent functions in vivo. 相似文献
79.
The particulate fraction of the calyx fluid of the endoparasitoid, Campoletis sonorensis, reduces host weight gain when manually injected into healthy Heliothis virescens larvae. Reduced weight gain of the host, H. virescens, is normally associated with parasitism by C. sonorensis. Electron microscopy has confirmed that the particulate fraction of the calyx fluid is composed of virus particles and it appears that this virus, injected with the egg at oviposition, actually reduces host weight gain. The effect of the virus is negated when the calyx fluid is exposed to ultraviolet light prior to injection. Furthermore, the calyx fluid is effective only if injected into hosts; there is no effect on host weight gain when hosts are fed or topically treated with the virus-containing calyx fluid. 相似文献
80.
Lagerström MC Fredriksson R Bjarnadóttir TK Fridmanis D Holmquist T Andersson J Yan YL Raudsepp T Zoorob R Kukkonen JP Lundin LG Klovins J Chowdhary BP Postlethwait JH Schiöth HB 《Genomics》2005,85(6):688-703
We present seven new vertebrate homologs of the prolactin-releasing hormone receptor (PRLHR) and show that these are found as two separate subtypes, PRLHR1 and PRLHR2. Analysis of a number of vertebrate sequences using phylogeny, pharmacology, and paralogon analysis indicates that the PRLHRs are likely to share a common ancestry with the neuropeptide Y (NPY) receptors. Moreover, a micromolar level of NPY was able to bind and inhibit completely the PRLH-evoked response in PRLHR1-expressing cells. We suggest that an ancestral PRLH peptide started coevolving with a redundant NPY binding receptor, which then became PRLHR, approximately 500 million years ago. The PRLHR1 subtype was shown to have a relatively high evolutionary rate compared to receptors with fixed peptide preference, which could indicate a drastic change in binding preference, thus supporting this hypothesis. This report suggests how gene duplication events can lead to novel peptide ligand/receptor interactions and hence spur the evolution of new physiological functions. 相似文献