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91.
Life expectancy in British Marfan syndrome populations 总被引:2,自引:0,他引:2
JR Gray AB Bridges RR West L. McLeish AG Stuart JCS Dean MEM Porteous M. Boxer SJ Davies 《Clinical genetics》1998,54(2):124-128
A total of 206 patients with Marfan syndrome were ascertained throughout genetic clinics in Wales and Scotland during the period 1970–1990. There were 45 deaths representing 22% of the cohort. Mean age at death was 45.3 ± 16.5 years. 50% median cumulative survival in the total cohort (n = 206) was 53 years for males and 72 years for females. Multivariate analysis confirmed severity as the best independent indicator of survival. These findings and survival curves will assist in the counselling of British families and individuals with Marfan syndrome. 相似文献
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93.
Permeation of human ovarian tissue with cryoprotective agents in preparation for cryopreservation 总被引:18,自引:10,他引:18
Newton H; Fisher J; Arnold JR; Pegg DE; Faddy MJ; Gosden RG 《Human reproduction (Oxford, England)》1998,13(2):376-380
The recent improvements in the treatment of cancer by chemo- and
radiotherapy have led to a significant increase in the survival rates of
patients with malignant disease, but at the expense of distressing side
effects. One major problem, especially for younger patients, is that
aggressive therapy destroys a significant proportion of the follicular
population, which can result in either temporary or permanent infertility.
Freeze-banking pieces of ovarian cortex prior to treatment is one strategy
for preserving fecundity. When the patient is in remission, fertility
could, theoretically, be restored by autografting the thawed tissue at the
orthotopic site or by growing isolated follicles to maturity in vitro.
Recent studies have found good follicular survival in frozen-thawed human
ovarian tissue but to optimize the process an effective cryopreservation
method needs to be developed. An essential part of such a technique is to
permeate the tissue with a cryoprotectant to minimize ice formation and the
extent of this equilibration is an important determinant of post-thaw
cellular survival. In the current study, we have investigated the diffusion
of four cryoprotective agents into human tissue at both 4 degrees C and 37
degrees C. We have also studied the effect of adding different
concentrations of the non penetrating cryoprotective agent, sucrose, to the
freezing media using the release of lactate dehydrogenase as a measure of
its protective effect. At 4 degrees C propylene glycol and glycerol
penetrated the tissue significantly slower than either ethylene glycol or
dimethyl sulphoxide. At the higher temperature of 37 degrees C all four
cryoprotectants penetrated at a faster rate, however concern about enhanced
toxicity prevents the use of these conditions in practice. Thus, the
results suggest that the best method of preparing tissue for freezing is
exposure for 30 min to 1.5 M solutions of ethylene glycol or dimethyl
sulphoxide at 4 degrees C; this achieved a mean tissue concentration that
was almost 80% that of the bathing solution. We also report that the
addition of low concentrations of sucrose to the freezing medium does not
have a significant protective effect against freezing injury.
相似文献
94.
We have developed a sandwich-type ELISA system for measuring total IgD levels in the serum of atopics and non-atopic controls. In this ELISA system, affinity purified goat anti-human IgD was used for capture. Results were superior to those obtained with monoclonal anti-human IgD antibody. No cross-reactivity could be demonstrated to IgG, IgM, IgA or IgE. The assay showed minimal non-specific binding even with initial serum dilutions of 1:2. The results obtained were reproducible among replicates (Mean CV +/- SEM = 0.03 +/- 0.002; n = 251), between dilutions (CV = 0.08 +/- 0.006; n = 108), and between assays (CV = 0.05 +/- 0.12; n = 5). We used routine radioimmunoassay for measuring total serum IgE. Using these assays total serum IgD and IgE levels were measured in 75 atopic patients and 33 normal subjects. None of the atopics had recent immunotherapy. As expected, the geometric mean serum IgE in atopics (373 ng/ml) was significantly higher than that in normal subjects (49 ng/ml) (P less than 0.01). However, geometric mean serum IgD was also significantly higher in atopics (20.3 micrograms/ml) than that in normal subjects (8.4 micrograms/ml) (P less than 0.02). In both atopic and normal groups, mean serum IgD level did not differ significantly on the bases of age, sex or asthmatic status. Furthermore, total serum IgD was not significantly correlated with total serum IgE (r = 0.14; P = 0.14; n = 108), indicating that immunoregulatory control of the basal levels of the two isotypes is not linked.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
An example of the `albumin' auto-agglutinating phenomenon is reported. This was found in the serum of a man dying from carcinoma of the stomach with liver secondaries. It is suggested that the serum factor is of a protein (probably globulin) nature, and may have been produced by the diseased liver. 相似文献
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99.
Peripheral neuropathy in the Twitcher mutant. A new experimental model of endoneurial edema 总被引:3,自引:0,他引:3
H C Powell R L Knobler R R Myers 《Laboratory investigation; a journal of technical methods and pathology》1983,49(1):19-25
The Twitcher mouse (Twi/Twi) is a recently identified mutant experimental model for human globoid leukodystrophy. Affected mice develop neurologic abnormalities with demyelination of white matter and peripheral nerve due to an inherited enzyme deficiency. The neuropathy has unusual pathologic features:severe interstitial edema and infiltration by eosinophils. To investigate its pathogenesis and to identify the mechanism of demyelination, we studied vascular permeability and measured endoneurial fluid pressure. Significantly increased endoneurial fluid pressure was detected in clinically affected animals (average, 6.4 cm H2O) versus controls (1.7 cm H2O), and these data are the first measurements of EFP to be reported in mice. Increased vascular permeability to horseradish peroxidase was visualized by electron microscopy with leakage of horseradish peroxidase between endothelial cells and flooding of the endoneurial interstitium. Numerous eosinophils were present in the interstitium, as well as some polymorphonuclear cells, occasional erythrocytes, and degranulating mast cells. Abnormalities of nerve fibers included swelling of Schwann cells with intracytoplasmic inclusions, demyelination, and remyelination. As well as being a model for globoid leukodystrophy, the Twitcher is the first spontaneously occurring experimental model for endoneurial edema and increased endoneurial fluid pressure. 相似文献
100.
L. C. Pele S. J. Thompson B. Kirkham R. P. H. Thompson J. J. Powell 《Inflammation research》2007,56(4):143-148
Objectives: The aims of this study were to determine, in peripheral blood mononuclear cells (PBMC), whether particulate antigen triggers
(i) an amplified cell proliferative response compared to soluble antigen and (ii) a dysfunctional response in cells derived
from patients with chronic inflammation and specifically in those with inflammatory bowel disease (IBD).
Subjects: Healthy volunteers (n = 17), inflammatory controls (n = 8) and patients with IBD (n = 17) were recruited from St Thomas’ and
Guys’ Hospital, London, UK.
Methods: Following optimisation of experimental conditions (0.1–10.0 μg/ml antigen), PBMC were stimulated with (i) 10.0 μg/ml recombinant
soluble heat shock protein 65 (hsp 65) and (ii) 1.0 and 10.0 μg/ml hsp 65 conjugated to microparticles (0.5 μm diameter).
PBMC proliferative responses were measured by 3H-Thymidine incorporation at day 5 and results compared between groups using unpaired t-test.
Results: Conjugation to microparticles of low dose hsp 65 significantly increased overall proliferative responses by 2–11 fold compared
to soluble antigen alone (p < 0.05). However, no specific PBMC proliferative dysregulation was noted in cells from subjects
with IBD.
Conclusions: Low dose antigen, in microparticulate form, leads to amplified cell proliferation in primary human cells, as showed previously
in cell lines and animal studies. However there is no abnormal proliferative response in cells from subjects with IBD.
Received 8 February 2006; returned for revision 7 March 2006; accepted by G. Wallace 25 October 2006 相似文献