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31.
Epidemiology of Reye's syndrome, United States, 1991-1994: comparison of CDC surveillance and hospital admission data 总被引:1,自引:0,他引:1
This investigation describes the epidemiology of Reye's syndrome (RS) during 1991-1994 and compares two different sources of information in the United States. Estimates of the incidence of RS from the Centers for Disease Control and Prevention (CDC) are compared with hospital inpatient data from approximately one third of the hospitals from HCIA, Inc. During 1991-1994, 48 RS cases were reported to the CDC and 93 RS hospitalizations based on HCIA data. When the HCIA data are extrapolated to the US population, there were an estimated 284 hospitalizations. Cases reported from both data sources were similar in distribution by onset, age, and sex. CDC data probably underestimate the incidence of RS due to incomplete reporting and HCIA data may overestimate it because not all cases were known to meet the CDC case definition. The true annual incidence of RS during the study years was probably between 0.2 and 1.1 cases per million population <18 years of age. 相似文献
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G.N. Stradling S.A. Gray J.C. Moody A. Hodgson K.N. Raymond P.W. Durbin 《International journal of radiation biology》2013,89(5):1269-1277
SummaryA hydroxypridinone derivative of desferrioxamine (Na-DFO-HOPO), a dihydroxamic derivative of diethylenetriaminepenta-acetic acid (ZnNa-DTPA-DX), and DTPA (CaNa3- and ZnNa3-DTPA) were tested at dosages of 30 μmol kg?1 for their ability to remove 238Pu or 241Am from rats after their intravenous injection as citrate or inhalation as nitrate. The most effective treatment regimen for injected Pu was the repeated administration of DFO-HOPO; by 7 days the body content was reduced to 8% of that in untreated animals. Repeated dosages of 3 μmol kg?1 DFO-HOPO were as effective as those of 30 μmol kg?1 DTPA. After inhalation of Pu nitrate, repeated treatment with DTPA, DTPA-DX or DFO-HOPO reduced the body content by 7 days to, respectively, 10, 15 and 31% of those in untreated animals. After inhalation of Am, DTPA-DX and DTPA were equally effective, the body contents being reduced to 7% of control values with repeated treatment. Injection of DFO-HOPO was ineffective for enhancing the elimination of inhaled or injected Am. The results confirm the strategy of examining the use of siderophore analogues for the decorporation of Pu or Am. However, at present DTPA should remain the agent of choice, particularly after inhalation. 相似文献
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Gene transfer to primary normal and malignant human hemopoietic progenitors using recombinant retroviruses 总被引:10,自引:0,他引:10
To study the feasibility of using retroviruses for gene transfer into human hemopoietic cells, various cell types were exposed to virus carrying the gene for neomycin resistance (neor). In preliminary studies using K562 cells as targets, we found that high viral titer and co-cultivation with viral producer cells rather than incubation in medium exposed to viral producer cells were important variables for achieving high frequencies of G418 resistant (G418r) colonies. The maximum frequency of G418r K562 colonies after co-cultivation with cells producing a neor virus titer of 4 X 10(6) cfu/mL was 60%. When primary human progenitors from normal marrow, fetal liver, or chronic myelogenous leukemia blood were exposed to high titer viral stocks, both with and without helper virus, under conditions optimized for K562 cells, maximum frequencies of G418r colonies were 3% to 16% for granulocyte macrophage progenitors and 2% to 6% for primitive erythroid progenitors. The presence of the neor gene in both G418r K562 and primary hemopoietic colonies was verified by Southern blot. Expression of the neor gene was shown by RNA spot blot. These data demonstrate efficient transfer and expression of the neor gene in both K562 cells and primary human hemopoietic cells from normal and leukemic individuals. 相似文献
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Heterogeneity of large granular lymphocyte proliferations: delineation of two major subtypes 总被引:5,自引:0,他引:5
Two major types of lymphocytosis of large granular lymphocytes (LGLs) were observed. The proliferating LGLs in each type had distinct immunophenotypes, functional characteristics, and probably belonged to different cell lineages. The more common form (Type A) consisted of cells derived from the T cell lineage and had the T suppressor/cytotoxic phenotype (T11+, T3+, T8+). The expression of the Leu 7 and HLA-DR antigen was variable. These cells did not have natural killer (NK) function but showed a variable degree of antibody-dependent cell-mediated cytotoxic (ADCC) activity. Neutropenia was invariably present and rheumatoid arthritis and autoantibodies were frequent associations. These lymphocytes had many similarities to the major type of LGLs present in normal adult bone marrow. The other type of LGL lymphocytosis (Type B) consisted of cells lacking the antigens T3 and T8 but expressing M1 and NKH1. These cells possessed strong NK and ADCC activity but their cell lineage was not clear. Neutropenia and autoimmune phenomena were not detected. The cytochemical characteristics of the LGL granules from both types of patients were similar but differences in ultrastructure were observed. LGLs from Type B patients proliferated in the presence of Interleukin 2 (IL-2) and 12- O-tetradecanoyl-phorbol-13 acetate (TPA). Significant changes in their basic T11+, T3-, T8- phenotype were not observed. IL-2 and TPA, however, had profound influence on the NK function of the cells with enhancement in the case of IL-2 and marked suppression when stimulated by TPA. 相似文献
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Aims To examine the reciprocal effects between the onset and course of alcohol use disorder (AUD) and normative changes in personality traits of behavioral disinhibition and negative emotionality during the transition between adolescence and young adulthood. Design Longitudinal–epidemiological study assessing AUD and personality at ages 17 and 24 years. Setting Participants were recruited from the community and took part in a day‐long, in‐person assessment. Participants Male (n = 1161) and female (n = 1022) twins participating in the Minnesota Twin Family Study. Measurements The effects of onset (adolescent versus young adult) and course (persistent versus desistent) of AUD on change in personality traits of behavioral disinhibition and negative emotionality from ages 17 to 24 years. Findings Onset and course of AUD moderated personality change from ages 17 to 24 years. Adolescent onset AUD was associated with greater decreases in behavioral disinhibition. Those with an adolescent onset and persistent course failed to exhibit normative declines in negative emotionality. Desistence was associated with a ‘recovery’ towards psychological maturity in young adulthood, while persistence was associated with continued personality dysfunction. Personality traits at age 11 predicted onset and course of AUD, indicating personality differences were not due to active substance abuse. Conclusions Personality differences present prior to initiation of alcohol use increase risk for alcohol use disorder, but the course of alcohol use disorder affects the rate of personality change during emerging adulthood. Examining the reciprocal effects of personality and alcohol use disorder within a developmental context is necessary to improve understanding for theory and intervention. 相似文献