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31.
This study was designed to find methods to reproducibly propagate human rotaviruses from fecal specimens and to determine the relationship between particle numbers and infectivity. Growth of virus was initially compared in primary and continuous lines of monkey kidney cells. Primary cells (African green and cynomolgus monkey kidney) supported virus growth directly from fecal specimens much more efficiently than did continuous lines of African green (CV-1) or rhesus (MA104) monkey kidney cells. Rotaviruses were grown in primary cells from 14 of 14 fecal specimens of different individuals collected over a 3-year period. Although rotaviruses in fecal samples could not always be grown in the continuous cell lines, two passages in primary cells appeared to fully adapt the viruses for propagation in the continuous cell line tested (MA104). The efficiency of rotavirus growth was quantified with five of the fecal isolates. It was calculated that, on the average, 1 out of every 46,000 particles in fecal specimens infected monkey kidney cells. After three passages in primary cells, an average of 1 out of every 6,600 progeny virus particles appeared to be infectious. Thus, rotaviruses in fecal specimens were consistently grown in primary cells, and passage in these cells both increased virus infectivity and adapted the viruses for growth in continuous cell lines. 相似文献
32.
How to use Chlamydia antibody testing in subfertility patients 总被引:1,自引:9,他引:1
Screening for tubal factor subfertility by means of Chlamydia antibody
testing (CAT) was introduced into the initial work-up of subfertile couples
several years ago. The results reported, however, are heterogeneous, and no
uniformity exists in cut-off levels of titres, or in definitions of tubal
factor subfertility. We performed a prospective cohort study to evaluate
the implications of varying the definitions of tubal pathology and of
modifying the cut-off levels on the clinical impact of CAT in predicting
tubal factor subfertility. In 227 consecutive patients who attended our
fertility clinic, the Chlamydia IgG antibody titre was determined and
related to tuboperitoneal abnormalities at laparoscopy as a reference
standard. According to received operating characteristic (ROC) curve
analysis, a titre of 16 is the optimum cut-off level. Increasing the
cut-off level improves specificity and positive likelihood ratio (LR+), at
the expense of sensitivity and negative LR (LR-). Changing the definition
of tubal factor subfertility from unspecified tuboperitoneal abnormalities
into extensive adhesions and/or bilateral distal tubal occlusion improves
LR+, LR- and kappa significantly. We conclude that CAT is more accurate in
predicting severe distal tubal pathology than unspecified tuboperitoneal
abnormalities. Although from a statistical point of view a titre of 16 is
the optimum cut-off level, from a clinical point of view 32 or 64 may be
preferable, depending on the aim of screening and the inception cohort.
相似文献
33.
M Zimecki C W Pierce M Janusz Z Wieczorek J Lisowski 《Archivum immunologiae et therapiae experimentalis》1987,35(3):339-349
Mitogenic properties of a proline-rich polypeptide were investigated. The mitogenic action of PRP was compared with the mitogenic action of Il-1. PRP was not mitogenic for thymocytes at doses 0.01-50 micrograms/ml. PRP, at doses 0.1-50 micrograms/ml, augmented the proliferative response of thymocytes to Con A in a similar fashion as Il-1. At doses higher than 10 micrograms/ml, PRP induced proliferation of lymph node cells and splenocytes as well as T cells from the lymph nodes. It did not, however, cause significant proliferation of B cells from the lymph nodes, at the doses used. PRP did not induce proliferation of an antigen specific Lyt 1+ T cell clone. Il-1 behaved in a similar way as PRP in all the tests described. We consider a possibility that under physiological conditions, at a very early stage of postneonatal life, PRP may replace some functions of Il-1. 相似文献
34.
Alternative splicing of exon 14 determines nuclear or cytoplasmic localisation of fmr1 protein isoforms 总被引:6,自引:9,他引:6
Impaired expression of the FMR1 gene is responsible for the fragile X
mental retardation syndrome. The FMR1 gene encodes a cytoplasmic protein
with RNA-binding properties. Its complex alternative splicing leads to
several isoforms, whose abundance and specific functions in the cell are
not known. We have cloned in expression vectors, cDNAs corresponding to
several isoforms. Western blot comparison of the pattern of endogenous FMR1
proteins with these transfected isoforms allowed the tentative
identification of the major endogenous isoform as ISO 7 and of a minor band
as an isoform lacking exon 14 sequences (ISO 6 or ISO 12), while some other
isoforms (ISO 4, ISO 5) were not expressed at detectable levels.
Surprisingly, in immunofluorescence studies, the transfected splice
variants that exclude exon 14 sequences (and have alternate C-terminal
regions) were shown to be nuclear. Such differential localisation was
however not seen in subcellular fractionation studies. Analysis of various
deletion mutants suggests the presence of a cytoplasmic retention domain
encoded in exon 14 and of a nuclear association domain encoded within the
first eight exons that appear however to lack a typical nuclear
localisation signal.
相似文献
35.
Mary Lou Jelachich Ellen K. Lakey Lisa Casten Susan K. Pierce 《European journal of immunology》1986,16(4):411-416
Purified splenic B cells from nonimmune mice were separated by counterflow centrifugal elutriation into 6 subpopulations containing cells of discrete sizes ranging from 119 to 200 μm3. B cells of each subpopulation were competent to process and present a native globular protein antigen, cytochrome c, to a cytochrome c-specific T cell hybrid. In all cases, the B cells' antigen-presenting function was radiation sensitive and did not require T cells or T cell products, since B cells fixed with paraformaldehyde effectively presented a carboxyl-terminal peptide fragment of cytochrome c containing the T cell determinant. Furthermore, the antigen-presenting function of B cells of each subpopulation was augmented by treatment with submitogenic doses of the F(ab')2 fragment of rabbit anti-mouse Ig antibodies, in that 10-30-fold fewer B cells were required and higher maximal T cell responses were achieved, indicating that B cells of all sizes are capable of being regulated in their antigen presentation function through their surface Ig. In addition, B cells of each subpopulation responded to soluble factors present in the supernatants of activated T cells as evidenced by an increase in volume and by the uptake of [3H]thymidine. These results indicate that B cells, regardless of size, are able to participate in at least two essential phases of T cell-dependent antibody responses, initiating the interaction by processing and presenting antigen to helper T cells and responding to soluble helper factors secreted by activated T cells. 相似文献
36.
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39.
When two sets of phagocytic cells participate simultaneously in the inflammatory process and bacterial killing, the relative contribution of each cell type is difficult to ascertain. The use of cell-specific antibody will permit selective depletion of one phagocyte population. We describe an experimental model of granulocytopenia which utilizes the immunoglobulin G fraction of an antigranulocyte serum. This material markedly depleted circulating polymorphonuclear leukocytes (PMN); within 2 h after injection of antigranulocyte globulin, PMN counts were at 19% of original levels and remained significantly depressed for 24 h. Granulocyte recruitment was also impaired, with only 5 x 10(3) PMN appearing in the lungs in response to an aerosol of Klebsiella, compared to 4.17 x 10(5) PMN in control animals (P less than 0.01). Most importantly, alveolar macrophages retained normal viability (97% versus 94% for control value, P not significant) normal phagocytic function, and normal bactericidal capacity. Antigranulocyte globulin is thus a valuable tool for the study of bacterial defense mechanisms. 相似文献
40.
I. M. Libermann H. García Pierce M. Labat J. Seigal 《Pflügers Archiv : European journal of physiology》1971,330(1):51-60
Summary Dogs were water depleted 2% of their body weight by the intraperitoneal injection of a hyperosmotic solution of saline and glucose (550 mOsm/l). During a 3-h experiment these water-depleted (WD) animals showed a significant decrease in blood pH, base excess (BE) and plasma bicarbonate (Bicp) and an increase in both hematocrit (Ht) and blood buffer capacity (BBC). These changes were quantitatively time-dependent. The rate change of pH, BE, and Bicp were –0.072 units h–1, –4.7 mEq/l h–1, and 2.9 mEq/l h–1, respectively. As control dogs showed no significant time-dependent changes in their blood acid-base status, the observed modifications in the experimental dogs were ascribed to water depletion. Increased endogenous acid production related to tissue hypoxia is suggested to be the mechanism that could explain the increased fixed acid accumulation observed in the water-depleted animals. 相似文献