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981.
J. A. Werner Stefan Gottschlich Benedikt J. Folz Tibor Goeroegh Burkard M. Lippert J.-D. Maass Heinrich Rudert 《Cancer immunology, immunotherapy : CII》1997,44(2):112-116
p53 antibodies are a new serological parameter of unknown potential in patients with malignancies. Their occurrence has been
described in various types of cancer patients. The mechanism underlying the immunization process is still unclear. We investigated
the incidence of p53 serum antibodies in 143 head and neck cancer patients with an enzyme-linked immunosorbent assay. The
post-therapy course of two matched study groups (n = 38 each), one p53-antibody-seropositive and one p53-antibody-seronegative, was followed up for 24 months. Thirty-nine head
and neck cancer patients (27.3%) were seropositive for p53 antibodies. During the follow-up, the p53-antibody-seropositive
patients accounted for more local tumor recurrences (n = 12 versus n = 8) and more tumor-related deaths (n = 11 versus n = 5) than did seronegative patients, and second primary tumors (n = 9 versus n = 0) occurred exclusively in seropositive patients. In total, therapy failures (recurrences, tumor-related deaths,
second primaries) were observed in 17/38 cases (44.7%) in the p53-antibody-seropositive group and in 8/38 cases (21.1%) in
the p53-antibody-seronegative group. These results, after a follow-up of 2 years, seem to indicate a prognostic value of p53
serum antibodies for therapy failure in patients with head and neck cancer.
Received: 5 December 1996 / Accepted: 4 January 1997 相似文献
982.
983.
984.
985.
986.
Although the contribution of community members to functional diversity is a key question of conservation ecology, its measurement and interpretation are rather problematic. In this paper, we suggest a novel method for decomposing functional diversity. To do this we consider functional units (i.e. species or a group of species with identical traits) as the functional building blocks of communities. Then we propose the use of a recently developed measure of functional diversity (called modified functional attribute diversity or MFAD) and suggest additive decomposition of MFAD into functional values contributed by the functional units. We point out that functional values are related to changes in MFAD if the functional unit is removed from the community. This property of decomposition allows the quantification of the contribution of community members to functional diversity. By studying artificial and actual communities we compare the performance of our new method with other recently developed contribution measures, which are based on dendrograms and ordinations. Both theoretical considerations and analyses of artificial and actual data sets suggest that the proposed method of calculating functional values expresses more explicitly the contribution of community members to functional diversity and hereby can be used as a simple, yet efficient method for searching for functional keystones in ecological communities or for quantifying the contribution of community members to functional diversity. 相似文献
987.
We construct a tractable model to describe the rate at which a knotted polymer is ejected from a spherical capsid via a small pore. Knots are too large to fit through the pore and must reptate to the end of the polymer for ejection to occur. The reptation of knots is described by symmetric exclusion on the line, with the internal capsid pressure represented by an additional biased particle that drives knots to the end of the chain. We compute the exact ejection speed for a finite number of knots L and find that it scales as 1/L. We establish a mapping to the solvable zero-range process. We also construct a continuum theory for many knots that matches the exact discrete theory for large L. 相似文献
988.
Effects of habitat fragmentation on carabids in forest patches 总被引:12,自引:0,他引:12
989.
Ensuring recovery of intact RNA from rat pancreas 总被引:1,自引:0,他引:1
Santokh S. Gill Rémy A. Aubin Claudia A. Bura Ivan H. A. Curran Tibor I. Matula 《Molecular biotechnology》1996,6(3):359-362
The isolation of intact RNA from rat pancreas is compromised by autolysis and by the presence of endogenous ribonucleases.
In order to ameliorate recovery we systematically investigated available RNA extraction methods and paid particular attention
to the influence of frozen storage and ribonuclease inhibition strategies on overall yield and quality of RNA. Modifications
to the basic procedure of Chomczynski and Sacchi (1987) are described which allow, reproducibly, to obtain rat pancreatic
RNA suitable for Northern blot hybridization, RT-PCR, and differential display analysis. 相似文献
990.
Exenatide, a synthetic peptide originally isolated from salivary secretions of Heloderma suspectum, like other subcutaneously injected peptides, can cause antibody formation. Despite that antibody formation has been observed in some patients, results from previous clinical trials have not shown safety and efficacy concerns in exenatide-naïve patients. The objective of this multicenter, open-label study was to investigate the response of anti-exenatide antibody formation and the incidence of immune-related and hypersensitivity reactions after exenatide re-exposure. Fifty-eight patients (57% male; 59 ± 10 years; weight 85 ± 19 kg; HbA1c 8.1 ± 0.9%; duration of diabetes 10 ± 5 years) were enrolled. At study initiation, 98.3% of patients were taking 1 or more antidiabetes drugs, including oral medication and various types of insulin. Treatment-emergent adverse events (TEAEs) at any time during the study were observed in 40 and 47% of patients with positive and negative treatment-emergent antibodies, respectively. Immune-related AEs were observed in 6 patients (4 were antibody positive). These AEs had not been reported in their previous exposure to exenatide. Re-exposure to exenatide did not result in increased hypersensitivity reactions. Overall, 72% of patients had a baseline to endpoint reduction in HbA1c (range −0.1 to −2.8%), and 87% of antibody negative versus 62% of antibody positive patients had an HbA1c endpoint reduction. The study design and the patients’ baseline characteristics, including diabetes treatment at study initiation, are confounding factors limiting clinical conclusions on exenatide's glycemic effect in this patient population. The study results indicate that anti-exenatide antibody formation did not increase the incidence of TEAEs in patients re-exposed to exenatide. 相似文献