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61.
Glomerular lesions secondary to calcium deposition in sarcoidosis have not been previously described, to our knowledge. Five renal biopsy specimens from four patients with sarcoidosis were studied by light, electron, and immunofluorescence microscopy. In addition to interstitial granulomatous nephritis and nephrocalcinosis, which were seen in all cases, segmental glomerular lesions characterized by marked thickening and wrinkling of the glomerular capillary walls and basophilic appearance of the altered basement membranes were present in three of the cases. Electron microscopic examination of the lesions revealed dramatic alteration of the glomerular ultrastructure. Numerous single and coalescent calcific microspherules were present within the basement membrane, the paramesangial zone, and the mesangium. The findings of immunofluorescence were noncontributory. The structural alterations caused by calcinosis of the glomerulus may be responsible for some of the frequent renal function abnormalities seen in sarcoidosis. 相似文献
62.
Chaim Brautbar Isac Cohen Esther Kahana Milton Alter Fritz Jørgensen Lars Lamm 《Tissue antigens》1977,10(4):291-302
The distribution of 24 HLA antigens of the A and B loci was investigated in 197 Israeli Jewish patients with multiple sclerosis (MS) from various Jewish ethnic origins including central and eastern Europe, countries bordering the Mediterranean, the Middle East and from native-born Israelis. The results were compared with the HLA antigen frequencies in a control sample of 455 unrelated individuals representing the general Jewish population. The frequency of HLA-Bw40 among all MS patients (15%) was significantly greater (P less than 0.001) than among the controls (7%). In contrast to the findings in MS patients from other populations, there was no increased frequency of A3 and B7 and Dw2 was present in only one out of 28 patients. The study showed a similar distribution of HLA-A and -B locus antigens, especially of Bw40, in Jews of diverse ethnic origins represented in the control group. 相似文献
63.
Barreiro E Gea J Matar G Hussain SN 《American journal of respiratory cell and molecular biology》2005,33(6):636-642
Oxidative protein modification involving carbonylation has recently been identified as an important factor in skeletal muscle dysfunction in patients with chronic obstructive pulmonary disease (COPD). However, the exact identity of modified proteins inside limb muscles of patients with COPD remains unknown. We used 2D electrophoresis, immunoblotting, and mass spectrometry to identify carbonylated proteins in the vastus lateralis muscle of 12 patients with COPD and 6 control subjects. Both creatine kinase (CK) and carbonic anhydrase III (CAIII) were identified as being strongly carbonylated in this muscle in both groups of subjects. Total CK activity, CK protein expression, and the intensity of CK carbonylation were significantly greater in the muscles of patients with COPD as compared with control subjects, whereas CAIII protein expression and intensity of carbonylation were similar in the two groups. In patients with COPD, CK activity and protein expression correlated positively with FEV(1) and V O(2)max, whereas the intensity of CK carbonylation correlated negatively with the same parameters. These results indicate that oxygen radicals selectively target CK and CAIII inside limb muscles of humans. The observation that the intensity of CK carbonylation correlates negatively with CK activity in limb muscles of patients with COPD suggests that carbonylation may have a deleterious effect on CK activity, and may contribute to impaired CK function in the limb muscles of these patients. 相似文献
64.
Graaff Esther de; Rouillard Patricia; J.Willems Patrick; P.T.Smits Arie; Rousseau Francois; A.Oostra Ben 《Human molecular genetics》1995,4(1):45-49
The fragile X syndrome is the most frequent cause of inheritedmental retardation. The molecular mechanism of the disorderis based on the expansion of a CGG repeat in the 5' UTR of theFMR1 gene In the majority of fragile X patients. The instabilityof this CGG repeat containing region is not restricted to theCGG repeat Itself but expands to the flanking region as well.We describe four unrelated fragile X patients that are mosaicfor both a full mutation and a small deletion in the CGG repeatcontaining region. Sequence analysis of the regions surroundingthe deletions showed that both the (CGG)n repeat and some flankingsequences were missing in all four patients. The 5' breakpointsof the deletions were found to be located between 7553bp proximal to the CGG repeat. This suggests the presence ofa hot spot region for deletions in the CGG repeat region ofthe FMR1 gene and emphasizes the instability of this regionIn the presence of an expanded CGG repeat. 相似文献
65.
66.
van Baalen CA Guillon C van Baalen M Verschuren EJ Boers PH Osterhaus AD Gruters RA 《European journal of immunology》2002,32(9):2644-2652
Recent studies indicate that the time required for virus-infected cells to become vulnerable for the activity of CTL is of significance for the capacity of CTL to control ongoing viral reproduction. To investigate whether this applies to the effectiveness of HIV-1-specific CTL, we measured virus production in cultures containing CD4(+) T cells inoculated with HIV at low multiplicity of infection, and CTL directed against an early protein, Rev, or a late protein, RT. The Rev-specific CTL prevented at least 2 log(10) more HIV-1 production, in 10 days, than similar numbers of RT-specific CTL. To study how CTL effectiveness depends on variations in the potency of effector functions and kinetics of HIV protein expression, we developed a mathematical model describing CTL-target cell interactions during successive infection cycles. The results show that substantially higher CTL-mediated target cell elimination rates are required to achieve control as there is less time for CTL to act before infected cells release progeny virions. Furthermore, in vitro experiments with HIV recombinant viruses showed that the RT-specific CTL were at least as effective as the Rev-specific CTL, but only if the RT epitope was expressed as part of the early protein Nef. Together these results indicate that CTL control ongoing HIV reproduction more effectively if they are able to recognize infected cells earlier during individual viral replication cycles. This provides rationale for immunization strategies that aim at inducing, boosting or skewing CTL responses to early regulatory proteins in AIDS vaccine development. 相似文献
67.
Immunogenicity and T cell recognition in swine of foot-and-mouth disease virus polymerase 3D 总被引:1,自引:0,他引:1
Immunization of domestic pigs with a vaccinia virus (VV) recombinant expressing foot-and-mouth disease virus (FMDV) 3D protein conferred partial protection against challenge with infectious virus. The severity reduction of the clinical symptoms developed by the challenged animals occurred in the absence of significant levels of anti-3D circulating antibodies. This observation suggested that the partial protection observed was mediated by the induction of a 3D-specific cellular immune response. To gain information on the T cell recognition of FMDV 3D protein, we conducted in vitro proliferative assays using lymphocytes from outbred pigs experimentally infected with FMDV and 90 overlapping peptides spanning the complete 3D sequence. The use of pools of two to three peptides allowed the identification of T cell epitopes that were efficiently recognized by lymphocytes from at least four of the five animals analyzed. This recognition was heterotypic because anti-peptide responses increased upon reinfection of animals with a FMDV isolate from a different serotype. The results obtained with individual peptides confirmed the antigenicity observed with peptide pools. Detection of cytokine mRNAs by RT-PCR in lymphocytes stimulated in vitro by individual 3D peptides revealed that IFN-gamma mRNA was the most consistently induced, suggesting that the activated T cells belong to the Th 1 subset. These results indicate that 3D protein contains epitopes that can be efficiently recognized by porcine T lymphocytes from different infected animals, both upon primary and secondary (heterotypic) FMDV infection. These epitopes can extend the repertoire of viral T cell epitopes to be included in subunit and synthetic FMD vaccines. 相似文献
68.
Dvorak Abeliovich Esther Maor Nava Bashan Rivka Carmi 《American journal of medical genetics. Part A》1989,32(3):346-349
We report on three patients with duplication of distal 22q. One patient is a de novo carrier of the translocation t(21;22) (p13;q11), the other two are offspring of a translocation carrier t(10;22) (q26;q12). The clinical manifestations of these patients demonstrate the variability of the dup(22q) syndrome. 相似文献
69.
Balsam KF Rothblum ED Beauchaine TP 《Journal of consulting and clinical psychology》2005,73(3):477-487
Lifetime victimization was examined in a primarily European American sample that comprised 557 lesbian/gay, 163 bisexual, and 525 heterosexual adults. Lesbian, gay, and bisexual (LGB) participants were recruited via LGB e-mail lists, periodicals, and organizations; these participants recruited 1 or more siblings for participation in the study (81% heterosexual, 19% LGB). In hierarchical linear modeling analyses, sexual orientation was a significant predictor of most of the victimization variables. Compared with heterosexual participants, LGB participants reported more childhood psychological and physical abuse by parents or caretakers, more childhood sexual abuse, more partner psychological and physical victimization in adulthood, and more sexual assault experiences in adulthood. Sexual orientation differences in sexual victimization were greater among men than among women. 相似文献
70.
Raúl Estévez Michael Pusch Carles Ferrer-Costa Modesto Orozco Thomas J. Jentsch 《The Journal of physiology》2004,557(2):363-378
All eukaryotic CLC Cl− channel subunits possess a long cytoplasmic carboxy-terminus that contains two so-called CBS (cystathionine β-synthase) domains. These domains are found in various unrelated proteins from all phylae. The crystal structure of the CBS domains of inosine monophosphate dehydrogenase (IMPDH) is known, but it is not known whether this structure is conserved in CLC channels. Working primarily with ClC-1, we used deletion scanning mutagenesis, coimmunoprecipitation and electrophysiology to demonstrate that its CBS domains interact. The replacement of CBS domains of ClC-1 with the corresponding CBS domains from other CLC channels and even human IMPDH yielded functional channels, indicating a high degree of structural conservation. Based on a homology model of the pair of CBS domains of CLC channels, we identified some residues that, when mutated, affected the common gate which acts on both pores of the dimeric channel. Thus, we propose that the structure of CBS domains from CLC channels is highly conserved and that they play a functional role in the common gate. 相似文献