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81.
Stein TP; Oram-Smith JC; Leskiw MJ; Wallace HW; Long LC; Leonard JM 《The American journal of physiology》1976,230(5):1321-1325
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83.
Dinwiddie S Heath AC Dunne MP Bucholz KK Madden PA Slutske WS Bierut LJ Statham DB Martin NG 《Psychological medicine》2000,30(1):41-52
BACKGROUND: This study was designed to determine lifetime prevalence of psychiatric disorders among twins who reported childhood sexual abuse (CSA), and to compare these rates with those among non-abused co-twins. The contribution of familial and individual-specific factors to reported sexual abuse was also examined. METHOD: Information about lifetime psychopathology and substance use was obtained by structured telephone interviews with 5995 Australian twins. Twins who reported a history of childhood sexual abuse (CSA) were contrasted on lifetime psychopathology with subjects without such a history; in addition, comparisons were made between same-sex twin pairs discordant for CSA. RESULTS: A history of CSA was reported by 5.9% of the women and 2.5% of the men. In the sample as a whole, those reporting CSA were more likely to receive lifetime diagnoses of major depression, conduct disorder, panic disorder and alcoholism, and were more likely to report suicidal ideation and a history of suicide attempt. Abused women, but not men, were also more likely to report social phobia. When comparisons were restricted to non-abused co-twins, no differences in psychopathology were seen. However, rates of major depression, conduct disorder and suicidal ideation were higher if both co-twins were abused than if the respondent alone reported CSA. Model-fitting indicated that shared environmental factors influenced risk for reported CSA in women, but not in men. CONCLUSION: The association between CSA and psychopathology arises at least in part through the influence of shared familial factors on both risk of victimization and risk of psychopathology. 相似文献
84.
Francisca Díaz‐González Manuel Parrón‐Pajares Ana Barcia‐Ramirez Karen E. Heath 《American journal of medical genetics. Part A》2020,182(4):628-631
Mesoaxial synostotic syndactyly with phalangeal reduction (MSSD) is an extremely rare autosomal recessive limb abnormality characterized by the fusion of third and fourth fingers. To date, only homozygous missense and frameshift mutations have been reported in BHLHA9 associated to MSSD. In this study, we report a patient who presented with clinical and radiological features of MSSD. A customized skeletal dysplasia NGS panel revealed the presence of two novel compounds heterozygous variants in BHLHA9: NM_001164405.1: c.[226A>T][269G>C]; p.[(Lys76*)][(Arg90Pro)]. Thus, this is the first case of MSSD in a nonconsanguineous family. 相似文献
85.
The present analyses examined genetic influences on alcohol metabolism and their possible relationship to risk of alcohol dependence. Subjects were 206 Australian twin pairs who participated in an alcohol challenge protocol in 1979–1981, in which they were given a 0.75 g/kg dose of alcohol; blood alcohol concentrations (BACs) measured at five times over a 3-hr period after alcohol ingestion were examined. Structural equation modeling, fitting a combined autoregressive and common factor model, indicated significant heritabilities for both men and women (h
2 range = 0.19–0.71), with significant parameter heterogeneity as a function of gender. In 1992–1993, both twins from 159 of the alcohol challenge pairs completed a telephone-administered psychiatric diagnostic interview. Repeated-measures MANOVAs were used to examine whether respondent's or cotwin's DSM-III-R alcohol dependence status, or parental history of alcohol problems, was associated with variation in alcohol metabolism. There was some evidence that individuals at increased genetic risk of alcohol dependence [with either a paternal history of alcohol problems (women) or an MZ male cotwin who reported a history of alcohol dependence by 1992–1993] showed lower initial BACs than other groups. However, this effect was not seen in those who themselves had a history of alcohol dependence by interview follow-up, perhaps because this relationship was already masked by a history of excessive drinking at baseline. 相似文献
86.
We tested the hypothesis that overestimations of performance by children with learning disabilities (LD) are self-protective and will dissipate following positive feedback. Twenty-three boys and 17 girls with LD (ages 10.6 to 13.5 years) and a control group of non-LD matched children (22 boys and 17 girls) provided a prediction of their performance on a spelling test prior to completing the test. Subsequently, they were randomly assigned to either a positive feedback or a no-feedback condition. Finally, they provided a second prediction of performance on an equivalent spelling test. In children with LD, there was a positive bias in their predictions of performance, and, following positive feedback, their predictions became accurate. In children without LD, there was no positive bias and no effect of feedback. The results provide further support for the presence of a positive illusory bias and for the self-protective hypothesis in children with LD. 相似文献
87.
Apoptotic cell death in mouse models of GM2 gangliosidosis and observations on human Tay-Sachs and Sandhoff diseases 总被引:5,自引:2,他引:5
Huang JQ; Trasler JM; Igdoura S; Michaud J; Hanal N; Gravel RA 《Human molecular genetics》1997,6(11):1879-1885
Tay-Sachs and Sandhoff diseases are autosomal recessive neurodegenerative
diseases resulting from the inability to catabolize GM2 ganglioside by
beta-hexosaminidase A (Hex A) due to mutations of the alpha subunit
(Tay-Sachs disease) or beta subunit (Sandhoff disease) of Hex A. Hex B
(beta beta homodimer) is also defective in Sandhoff disease. We previously
developed mouse models of both diseases and showed that Hexa-/- (Tay-Sachs)
mice remain asymptomatic to at least 1 year of age while Hexb-/- (Sandhoff)
mice succumb to a profound neurodegenerative disease by 4-6 months of age.
Here we find that neuron death in Hexb-/- mice is associated with apoptosis
occurring throughout the CNS, while Hexa-/- mice were minimally involved at
the same age. Studies of autopsy samples of brain and spinal cord from
human Tay-Sachs and Sandhoff diseases revealed apoptosis in both instances,
in keeping with the severe expression of both diseases. We suggest that
neuron death is caused by unscheduled apoptosis, implicating accumulated
GM2 ganglioside or a derivative in triggering of the apoptotic cascade.
相似文献
88.
The bias favoring deletion over inversion in DH-JH rearrangement has been
known for years, but the underlying mechanism has yet to be fully defined.
It has been suggested that the ratio of deletion/inversion is determined by
the combined effect of two factors: (i) the relative strengths of 5' and 3'
recombination signal sequences (RSS) of a DH segment, and (ii) the
efficiency with which the deletional product (one joint) forms relative to
the inversional product (two joints). In this study, we analyzed for the
first time the effect of factor 1 alone on the biased 3' RSS utilization in
DH-JH joining by using deletional plasmids in an extrachromosomal substrate
V(D)J recombination assay. It was found that the 3' RSS and associated
coding end (12 bp) mediate recombination more efficiently than the 5'
RSS/coding end DH-JH plasmids. These results demonstrate that the effect of
the RSS/coding end alone can account, at least partially, for the
predominant deletion in DH-JH recombination. The potential effect of the
relative strength of RSS and associated coding end on the ordered
rearrangement of DH-JH followed by VH to DH-JH was also assessed. When
recombination frequencies of D-->J (3' DH to J3) were compared with
frequencies of V-- >D (VHPJ14 to 3' DH or VHOX2 to 3' DH), it was found
that V-->D joining was, if anything, more efficient than D-->J
joining. Therefore, if all three segments were accessible, RSS/coding end
effects would not contribute to the ordered rearrangement of the IgH locus.
相似文献
89.
JM Hopkin 《Current opinion in immunology》1997,9(6):788-792
Atopy — a T helper 2 cell driven hypersensitivity to innocuous antigens (allergens) which causes most cases of asthma — is of complex genetic and environmental origins. There is compelling epidemiological evidence for a rise in atopic disease in ‘westernised’ communities. The changing pattern of microbial exposure in early childhood is suggested to be the principal candidate mechanism for this rise. 相似文献
90.