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101.
102.
天麻丸中天麻的显微定量研究 总被引:2,自引:0,他引:2
目的 :制定天麻在天麻丸中的显微定量标准。方法 :用显微定量法 ,以天麻的木化厚壁细胞为显微特征物 ,对天麻丸中的天麻进行测定。结果 :天麻含量与每mg特征数呈显著的线性正相关。回归方程为 y =6 2 35x 1 80× 10 -3 (γ =0 9999,a =0 0 5 )。结论 :显微定量法测定天麻丸中天麻的含量是可行的 ,结果可靠。 相似文献
103.
Savaraj N Xu R Landy H Lai S Sternau L Solomon J Wu C Lampidis T Feun L 《Oncology reports》1997,4(4):857-861
Topoisomerase I (TOP I) and II (TOP II) activities and their corresponding levels were analyzed in 27 primary brain tumors and 32 lung cancers (28 NSCLC, 4 SCLC). The TOP I and II activities in primary brain tumors varied from 500-2,000 units/mg and 100-3,000 units/mg respectively. Their corresponding levels varied from <0.01-3.30 (TOP I) and 0.24-8.30 (TOP II) arbitrary units. In lung cancer, the TOP I and II activities ranged from 1,000-4,000 and 500-4,000 units/mg respectively with their levels ranging from 0.30-61.60 and 0.2-14.2 arbitrary units respectively. These parameters were compared in both tumors using the Wilcoxon rank sums test, the difference were statically significance for all four parameters with a p<0.0001 for TOP I and II activities and TOP I levels and p<0.09 for TOP II levels. Using linear regression analysis, there was no correlation between TOP I and II activities and their corresponding levels in primary brain tumor. However, in lung cancer, the relationship between TOP I activities and levels were linear with r(2)=0.2 and p<0.0094, but not for TOP II activity and their levels. There was no relationship between TOP I and TOP II levels in the same tumor for both types of cancer. The future clinical implication of these findings are discussed. 相似文献
104.
Nishio M Xu L Sasaki M Haga S Okumoto M Mori N Sarkar NH Acha-Orbea H Enami J Imai S 《Breast cancer (Tokyo, Japan)》1994,1(2):89-94
Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid. 相似文献
105.
G. Mantovani A. Macciò R. Versace M. Pisano P. Lai S. Esu M. Ghiani D. Dessì E. Turnu M. C. Santona R. Cherchi G. S. Del Giacco 《Journal of molecular medicine (Berlin, Germany)》1995,73(8):409-416
This work was designed to study the proliferative response of tumor-associated lymphocytes (TAL) from neoplastic effusions against autologous tumor cells and the immunophenotype pattern of TAL from neoplastic effusions and that of PBMC of the same patients. We also compared the serum levels of the cytokines interleukin (IL) 1, 2 and 6, tumor necrosis factor- (TNF) and soluble IL-2 receptor (sIL-2R) with those present in neoplastic effusions of the same patients. Moreover, we examined the ability of TAL and peripheral blood mononuclear cells (PBMC) to produce and release the cytokines and sIL-2R and to express membrane CD25 following their stimulation with phytohemagglutinin (PHA) in vitro. Finally, we compared the cytokines/sIL-2R production and membrane CD25 expression by PHA-stimulated PBMC of the patients with neoplastic effusions with a series of 90 cancer patients without neoplastic effusions and 20 normal healthy subjects. Thirteen neoplastic pleural and eight peritoneal effusions were collected from 11 patients with primary lung cancer, 7 with primary epithelial ovarian cancer, 1 with breast cancer, 1 with pleural mesothelioma, and 1 with pancreatic cancer. The proliferative response of TAL from neoplastic effusions against autologous tumor cells was lower than the response to PHA, IL-2, and anti-CD3, but significant. The percentage distribution of CD3+ and CD8+ lymphocyte subpopulations was higher in peritoneal than in pleural effusions, while the CD16+ subset was higher in pleural than in peritoneal effusions. The percentage distribution of CD16+ was significantly lower in pleural effusions than in PBMC of patients with pleural effusions. The CD39 antigen was higher on TAL from peritoneal effusions than on PBMC of the same patients. The levels of IL-1 and sIL-2R in peritoneal effusions did not differ from those measured in the sera of the same patients, while the levels of IL-2, IL-6, and TNF were higher in the peritoneal effusions. The levels of IL-2, IL-6, TNF, and sIL-2R, but not IL-1, in pleural effusions were significantly higher than those found in the sera of the same patients. The amounts of IL-2 and IL-6 produced by TAL were generally higher than those released by PBMC. The secretion of cytokines IL-1, IL-2, and sIL2R by PHA-stimulated PBMC was lower, but IL-1 and IL-6 secretion was higher in cancer patients with neoplastic effusions than in either cancer patients without neoplastic effusions or normal subjects. The CD25 expression on PHA-stimulated PBMC derived from cancer patients with neoplastic effusions was in the same range as that of cancer patients without neoplastic effusions and normal subjects. These findings suggest that TAL may be able to produce cytokines and may be amenable to immune manipulation.Abbreviations
FITC
Fluorescein-isothiocyanate
-
IL
Interleukin
-
mAb
Monoclonal antibody
-
MHC
Major histocompatibility complex
-
NK
Natural killer
-
PBMC
Peripheral blood mononuclear cells
-
PHA
Phytohemagglutinin
-
TAL
Tumor-associated lymphocytes
-
TIL
Tumor-infiltrating lymphocytes
-
TNF
Tumor necrosis factor-
-
sIL-2R
Soluble interleukin-2 receptor 相似文献
106.
Quartu M Lai ML Del Fiacco M 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》1995,100(Z1):205-211
By means of immunohistochemistry the presence of the growth-associated protein GAP-43 and its codistribution with substance P (SP) and calcitonin gene-related peptide (CGRP) are studied in the human spinal trigeminal, gracile, and cuneate nuclei at perinatal and adult life stages. The results obtained show that the distribution pattern of GAP-43 in the areas examined varies with age and that the immunohistochemical detectability of the protein persists in discrete subregions of the trigeminal and cuneate nuclei of the adult, where its localization closely matches that of SP and CGRP. It is suggested that neuronal plasticity may be pronounced throughout life in areas of the human nervous system involved in the neurotransmission of protopathic stimuli at the first synaptic level. Discrete subregions of the cuneate nucleus, bearing neurochemical characteristics strikingly similar to those of the substantia gelatinosa of the trigeminal subnucleus caudalis are pointed out. 相似文献
107.
p53 is the most frequently altered suppressor gene in human cancers. The genotypic and corresponding phenotypic abnormalities of this gene in head and neck squamous cell carcinoma (HNSCC) remain undefined. We analyzed the loss of heterozygosity (LOH) by restriction fragment length polymorphism (RFLP) at three polymorphic loci in the p53 gene and performed immunohistochemistry (MC) for its protein on paraffin-embedded tumor tissue from 20 previously sequenced tumor specimens. LOH was noted at one or more of the three polymorphic sites within the p53 gene in 12 (67%) of the 18 informative samples. Concordance between LOH and mutations was observed in 14 (78%) cases. Twelve (60%) tumors with point mutations were immunohistochemically reactive to p53 antibody and two (10%) lacked both genetic and immunohistochemical alterations. In six tumors (30%) contradictory results between immunohistochemistry and molecular analysis were observed. Our data indicate that: (i) simultaneous deletion and mutation of both p53 alleles was observed in the majority of head and neck squamous carcinomas and implicate this gene in the oncogenesis of these neoplasms, (ii) p53 immunohistochemical analysis may not fully account for the different molecular alterations of this gene, and (iii) no correlation between p53 abnormalities and clinicopathologic or DNA content characteristics of HNSCC was found. 相似文献
108.
Lai HC Corey M FitzSimmons S Kosorok MR Farrell PM 《The American journal of clinical nutrition》1999,69(3):531-538
BACKGROUND: Differences in growth status of patients with cystic fibrosis (CF) between the United States and Canada were reported in the 1980s based on analysis of data from 2 regional CF centers. OBJECTIVE: We evaluated the current growth status of the entire CF population in the United States and Canada in view of recent advances in the treatment of CF. DESIGN: Growth data from the 1992-1994 CF Patient Registries were analyzed. RESULTS: Mean height and weight were at approximately the 30th percentile for children with CF in the United States. Mean height and weight were 4-5 percentiles higher in children with CF in Canada than in those in the United States (P < 0.01), but percentages of ideal weight (104%) were similar in both populations. In adults with CF, mean height was similar at the 37th percentile; however, weight (26th compared with the 21st percentiles) and percentage of ideal weight (93% compared with 90%) were significantly higher in Canada than in the United States. Differences related to sex and age were similar in both countries for all indexes, which showed a high prevalence of underweight in infants and in older patients, but little sex discrepancy. CONCLUSION: We observed substantially smaller differences in the growth indexes of CF patients between the United States and Canada compared with results from the 1980s. These findings reflect significant improvements in the nutritional status of US patients in recent years. However, caution is required in the direct comparison of mean percentiles from reports using different growth standards because there are systematic differences in growth standards, which affect, in particular, the comparison of growth in males and females. 相似文献
109.
Climate, traffic-related air pollutants, and asthma prevalence in middle-school children in taiwan 总被引:7,自引:0,他引:7 下载免费PDF全文
Guo YL Lin YC Sung FC Huang SL Ko YC Lai JS Su HJ Shaw CK Lin RS Dockery DW 《Environmental health perspectives》1999,107(12):1001-1006
This study compared the prevalence of asthma with climate and air pollutant data to determine the relationship between asthma prevalence and these factors. We conducted a nationwide survey of respiratory illness and symptoms in middle-school students in Taiwan. Lifetime prevalences of physician-diagnosed asthma and of typical symptoms of asthma were compared to air monitoring station data for temperature, relative humidity, sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with aerodynamic diameter [less than/equal to] 10 microm (PM(10)). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Asthma prevalence rates adjusted for age, history of atopic eczema, and parental education were associated with nonsummer (June-August) temperature, winter (January-March) humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, for both girls and boys. Nonsummer temperature, winter humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, were positively associated with the prevalence of asthma in middle-school students in Taiwan. 相似文献
110.
The possible association between the risk of rectal cancer and hardness levels in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. All eligible rectal cancer deaths (986 cases) of Taiwan residents from 1990 through 1994 were compared with deaths from other causes (986 controls), and the hardness levels of the drinking water used by these residents were determined. Data on water hardness throughout Taiwan were collected from Taiwan Water Supply Corporation (TWSC). The control group consisted of people who died from other causes and the controls were pair matched to the cases by sex, year of birth, and year of death. The results show a significant negative relationship between drinking water hardness and rectal cancer mortality. Odds ratio and 95% confidence intervals were 1.24 (1.01-1. 55) and 1.38 (1.10-1.73), respectively, for exposure to moderately hard water and soft water compared with the use of hard water. Trend analyses showed an increasing odds ratio for rectal cancer with decreasing levels of hardness in drinking water. This is an important finding for the Taiwan water industry and human health. 相似文献