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61.
Sixty-one 12- to 18-year-olds were randomized to 8-10 sessions of behavior management training (n = 20), problem-solving and communication training (n = 21), or structural family therapy (n = 20). Families were assessed at pre- and posttreatment and 3-month follow-up. All treatments resulted in significant reductions in negative communication, conflicts, and anger during conflicts and improved ratings of school adjustment, reduced internalizing and externalizing symptoms, and decreased maternal depressive symptoms. Most outcomes remained stable between posttreatment and follow-up, and some continued to improve over this time. Despite group improvements, analyses of clinically significant change and clinical recovery within Ss showed that only 5-30% reliably improved from treatment and only 5-20% recovered following treatment. The three treatments did not differ in these rates.  相似文献   
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63.
We tested the hypothesis that enhanced nitric oxide (NO) opposes fetal peripheral vasoconstrictor responses to acute hypoxaemia via actions involving the carotid chemoreflex and the adrenal medulla. The hypothesis was tested in the late gestation ovine fetus using a novel NO clamp technique, which involves fetal combined treatment with the NO synthase inhibitor, l -NAME, and the NO donor, sodium nitroprusside. In contrast to treatment with l -NAME alone, combined fetal treatment with l -NAME and nitroprusside prevents generalized vasoconstriction and pronounced hypertension, not only maintaining basal cardiovascular function, but also permitting blockade of the de novo synthesis of NO during hypoxaemia while compensating for the tonic production of the gas. Under general anaesthesia, seven sheep fetuses were surgically prepared with catheters and a femoral Transonic flow probe. Five days after surgery, fetuses were subjected to a 3 h protocol: 1 h normoxia, 1 h hypoxaemia and 1 h recovery. Fetal hypoxaemia was induced during either fetal infusion with saline or treatment with the NO clamp. During saline infusion, fetuses responded to hypoxaemia with transient bradycardia, femoral vasoconstriction and increases in plasma noradrenaline and adrenaline. During fetal treatment with the NO clamp, bradycardia persisted and there were greater peripheral vasoconstrictor and catecholaminergic responses to hypoxaemia. Further analysis showed that NO clamp treatment enhanced the chemoreflex component of the fetal cardiovascular defence to acute hypoxaemia. These data support the hypothesis that enhanced NO synthesis during acute hypoxaemia offsets fetal peripheral vasoconstrictor responses to hypoxaemia via chemoreflex and adrenomedullary actions.  相似文献   
64.
Understanding the regulation of immune responses is central for control of autoimmune and infectious disease. In murine models of autoimmunity and chronic inflammatory disease, potent regulatory T lymphocytes have recently been characterized. Despite an explosion of interest in these cells, their relevance to human disease has been uncertain. In a longitudinal study of malaria sporozoite infection via the natural route, we provide evidence that regulatory T cells have modifying effects on blood-stage infection in vivo in humans. Cells with the characteristics of regulatory T cells are rapidly induced following blood-stage infection and are associated with a burst of TGF-beta production, decreased proinflammatory cytokine production, and decreased antigen-specific immune responses. Both the production of TGF-beta and the presence of CD4+CD25+FOXP3+ regulatory T cells are associated with higher rates of parasite growth in vivo. P. falciparum-mediated induction of regulatory T cells may represent a parasite-specific virulence factor.  相似文献   
65.
In a prospective longitudinal study, academic achievement scores were obtained from youth 5 to 15 years of age who sustained mild-moderate (n = 34) or severe (n = 43) traumatic brain injuries (TBI). Achievement scores were collected from baseline to 5 years following TBI and were subjected to individual growth curve analysis. The models fitted age at injury, years since injury, duration of impaired consciousness, and interaction effects to Reading Decoding, Reading Comprehension, Spelling, and Arithmetic standard scores. Although scores improved significantly over the follow-up relative to normative data from the standardization sample of the tests, children with severe TBI showed persistent deficits on all achievement scores in comparison to children with mild-moderate TBI. Interactions of the slope and age parameters for the Arithmetic and Reading Decoding scores indicated greater increases over time in achievement scores of the children injured at an older age, but deceleration in growth curves for the younger children with both mild-moderate and severe TBI. These results are compatible with the hypothesis that early brain injuries disrupt the acquisition of some academic skills. Hierarchical regression models revealed that indexes of academic achievement obtained 2 years following TBI had weak relations with the duration of impaired consciousness and socioeconomic status. In contrast, concurrent cognitive variables such as phonological processing and verbal memory accounted for more variability in academic scores. Given the significant and persistent decrement in basic academic skills in youth with severe TBI, it is clear that head-injured youth require intensive, long-term remediation and intervention not only of the academic skills themselves, but also of those cognitive abilities that support the development and maintenance of reading and math.  相似文献   
66.
Rhoads CS  Elmore JG  Fletcher S 《The New England journal of medicine》2000,342(26):2002; author reply 2002-2002; author reply 2003
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67.
Insulin-dependent diabetic and control subjects of Japanese origin were HLA-DRB1, -DQB1, and -DQA1 typed using restriction fragment length polymorphism analysis and sequence-specific oligonucleotide gene probing. The DQA1 allele DQA1*0301 was positively associated with the disease [48/52 (92%) diabetic patients versus 44/64 (69%) control subjects, Pc less than 0.03, RR = 4.97]. Alleles of the DRB1 and DQB1 genes showed no significant association with the disease. The frequency of DQB1 genotypes encoding the amino acid aspartic acid at position 57 of the DQ beta chain did not differ significantly between subjects with insulin-dependent diabetes mellitus (IDDM) and controls. These findings suggest that a susceptibility allele for IDDM in the Japanese is more closely associated with the DQA1 gene than the DQB1 gene.  相似文献   
68.
69.
The nosologic status of fibrous dysplasia (FD), a well-known and relatively common bone lesion, is controversial. Information collected by the CHromosomes And MorPhology (CHAMP) study group on published and unpublished cases of fibrous dysplasia shows the presence of clonal chromosome changes in at least a proportion of these lesions. The chromosome aberrations found in FD lesions have been quite variable and have included both structural and numerical changes. Two of the three cases investigated at the study group had trisomy 2 as the sole acquired anomaly. Combined with previously published data, +2 and rearrangements involving chromosome band 12p13 have each been detected in 3 of 8 cases with abnormal karyotype of 11 in which chromosomal analysis has been performed, suggesting that FD is a neoplastic lesion rather than a "dysplastic" process, as has been generally believed and as implied by its very name.  相似文献   
70.
Inflammatory pseudotumors (IPTs) of the lymph node and spleen are an uncommon, benign cause of lymphadenopathy and/or splenomegaly that often bear striking clinicopathologic similarities to the inflammatory myofibroblastic tumors (IMTs) found in soft tissues. These tumors have classically been grouped together under the umbrella category of "inflammatory pseudotumor." Recent evidence shows that IMTs are in fact neoplastic processes that often harbor balanced chromosomal translocations involving the ALK kinase gene. These translocations result in expression of ALK kinase in IMTs as assessed by immunohistochemical studies. However, the relationship between IMT and IPT of the lymph node and spleen is uncertain. To determine if ALK tyrosine kinase expression is also present in IPT, 13 cases of IPT (9 involving lymph nodes, 4 splenic lesions) were examined for the presence of ALK tyrosine kinase by immunohistochemical staining on paraffin-embedded tissue. In addition, in situ hybridization studies for Epstein-Barr virus--encoded RNAs (EBER) and immunoperoxidase studies for human herpesvirus-8 (HHV8)--specific proteins were performed. All cases had clinical, morphologic, and immunophenotypic findings typical of IPT and had varying proportions of fibroblastic and inflammatory components. Age ranged from 11 to 75 (median, 40) years; 8 subjects were male, and 5 were female. None of the cases (0 of 13) had positive staining for ALK kinase or HHV8, and in 1 a lymph node (1 of 13) was focally positive for EBV (EBER) by in situ hybridization. The absence of ALK kinase as detected by immunohistochemical studies in IPT of the lymph node and spleen suggests that this entity is biologically distinct from the histologically similar IMT.  相似文献   
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