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51.
A new approach for the M-typing of Streptococcus pyogenes is reported. Oligonucleotide primers were used in a PCR to amplify the N-terminal region of the emm gene. The presence of the PCR amplification product is associated with the corresponding M serotype. This technique offers potential advantages over other molecular typing methods. 相似文献
52.
Roberto Merletti Mohamed A. Sabbahi Carlo J. De Luca 《European journal of applied physiology》1984,52(3):258-265
Summary A study was performed to investigate the changes that occur in the median frequency of the myoelectric signal during local ischemia or reduction of intramuscular temperature produced by surface cooling. Data was obtained from experiments which involved the first dorsal interosseous muscle of 10 female and 16 male subjects. These subjects were asked to perform isometric constant-force abduction contractions of the index finger at 20% and 80% of maximal voluntary contraction level. The initial median frequency (IMF) of the myoelectric signal during the first 0.5 s of contraction was calculated. Results showed a significant reduction of the IMF in contractions performed under ischemic conditions; upon release, the IMF recovered quickly. At 80% maximal voluntary level of contraction, a greater decrease of the IMF was recorded. Similar results were demonstrated during reduction of intramuscular temperature with gradual recovery of the IMF after cooling. These results demonstrate that the median frequency of the myoelectric signal displays behavior similar to that reported for conduction velocity and this is consistent with the notion that accumulation of metabolic byproducts in muscle tissue causes a decrease in the conduction velocity of the muscle fibers.Dr. R. Merletti was on a leave of absence from the Institute of Electrical Engineering, Politecnico di Torino, Italy 相似文献
53.
Bedside to bench and back again: how animal models are guiding the development of new immunotherapies for cancer 总被引:3,自引:0,他引:3
Finkelstein SE Heimann DM Klebanoff CA Antony PA Gattinoni L Hinrichs CS Hwang LN Palmer DC Spiess PJ Surman DR Wrzesiniski C Yu Z Rosenberg SA Restifo NP 《Journal of leukocyte biology》2004,76(2):333-337
Immunotherapy using adoptive cell transfer is a promising approach that can result in the regression of bulky, invasive cancer in some patients. However, currently available therapies remain less successful than desired. To study the mechanisms of action and possible improvements in cell-transfer therapies, we use a murine model system with analogous components to the treatment of patients. T cell receptor transgenic CD8+ T cells (pmel-1) specifically recognizing the melanocyte differentiation antigen gp100 are adoptively transferred into lympho-depleted mice bearing large, established, 14-day subcutaneous B16 melanoma (0.5-1 cm in diameter) on the day of treatment. Adoptive cell transfer in combination with interleukin interleukin-2 or interleukin-15 cytokine administration and vaccination using an altered form of the target antigen, gp100, can result in the complete and durable regression of large tumor burdens. Complete responders frequently develop autoimmunity with vitiligo at the former tumor site that often spreads to involve the whole coat. These findings have important implications for the design of immunotherapy trials in humans. 相似文献
54.
Guidelines for the appropriate use of genetic tests in infertile couples 总被引:10,自引:0,他引:10
Foresta C Ferlin A Gianaroli L Dallapiccola B 《European journal of human genetics : EJHG》2002,10(5):303-312
Research on genetic causes of male and female infertility rapidly expanded in the last years, following the development of in vitro fertilising techniques. Genetic tests are now available to explore the cause of the infertility and assess the risk of a given couple to transmit its genetic characteristics. This allows at-risk couples to take an informed decision when electing for a medically assisted reproduction. It also allows the professionals to offer a prenatal diagnosis when appropriate. Thus, the genetic work-up of the infertile couple has become good practice for an appropriate diagnosis, treatment and prognostic assessment. The lack of national or international rules for the genetic approach to the infertile couple, prompted the Italian community of professionals in the field of reproductive medicine to join and set up guidelines for the genetic diagnosis of male and female infertility. The group of clinical and research experts is representative of 12 national scientific societies and was supported by external experts from four international societies. We examine the clinically relevant genetic causes of male and female infertility and suggest the category of patients for which each genetic test is recommended or optional, both for an accurate diagnosis and prior to ART. 相似文献
55.
De Luca A Buccino A Gianni D Mangino M Giustini S Richetta A Divona L Calvieri S Mingarelli R Dallapiccola B 《Human mutation》2003,21(2):171-172
The high mutation rate at the NF1 locus results in a wide range of molecular abnormalities. The majority of these mutations are private and rare, generating elevated allelic diversity with a restricted number of recurrent mutations. In this study, we have assessed the efficacy of denaturing high-performance liquid chromatography (DHPLC), for detecting mutation in the NF1 gene. DHPLC is a fast and highly sensitive technique based on the detection of heteroduplexes in PCR products by ion pair reverse-phase HPLC under partially denaturing conditions. We established theoretical conditions for DHPLC analysis of all coding exons and splice junctions of the NF1 gene using the WAVEmaker software version 4.1.40 and screened for mutations a panel of 40 unrelated NF1 patients (25 sporadic and 15 familial), genetically uncharacterized. Disruptive mutations were identified in 29 individuals with an overall mutation detection rate of 72.5%. The mutations included eight deletions (exons 4b, 7, 10a, 14, 26, and 31), one insertion (exon 8), nine nonsense mutation (exons 10a, 13, 23.1, 27a, 29, 31, and 36), six missense mutations (exons 15, 16, 17, 24, and 31), four splice errors (exons 11, 14, 36, and 40) and a complex rearrangement within exon 16. Eighteen (62%) of the identified disruptive mutations are novel. Seven unclassified and three previously reported polymorphisms were also detected. None of the missense mutations identified in this study were found after screening of 150 controls. Our results suggest that DHPLC provides an accurate method for the rapid identification of NF1 mutations. 相似文献
56.
Malignant granular cell tumor of the lateral femoral cutaneous nerve: report of a case with cytogenetic analysis 总被引:5,自引:0,他引:5
Di Tommaso L Magrini E Consales A Poppi M Pasquinelli G Dorji T Benedetti G Baccarini P 《Human pathology》2002,33(12):1237-1240
Malignant granular cell tumors (MGCTs) are rare neoplasms of uncertain histogenesis. We report a case of MGCT involving a peripheral nerve with peritoneal and omental dissemination in which cytogenetic findings are available. Our results show that MGCTs share some cytogenetic abnormalities with malignant peripheral nerve sheath tumors (MPNSTs), supporting the hypothesis that they may represent histogenetically related lesions. 相似文献
57.
S McGregor J Strauss N Bulgin V De Luca C J George M Kovacs J L Kennedy 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(5):696-700
Recently, evidence has accumulated for the role of neurotrophic processes in mood disorders. Neurotrophins operate on receptors, one of which is the p75 neurotrophin receptor (p75(NTR)). We examined three p75(NTR) markers at the p75(NTR) gene, including a missense polymorphism that changes serine to leucine (S205L), for association with suicide attempt (SA) in 203 childhood-onset mood disorder (COMD) cases. There was no difference between COMD suicide attempters and COMD non-attempters with logistic regression models for any of the three markers. We also compared the three polymorphisms between 192 COMD cases and 192 matched healthy controls and found no significant differences between COMD and healthy controls. Our results do not support an association of the p75(NTR) S205L polymorphism with risk for COMD or SA in COMD. 相似文献
58.
Lipid abnormalities in HIV-infected patients are not correlated with lopinavir plasma concentrations
59.
What and where in human audition: selective deficits following focal hemispheric lesions 总被引:8,自引:0,他引:8
Clarke S Bellmann Thiran A Maeder P Adriani M Vernet O Regli L Cuisenaire O Thiran JP 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,147(1):8-15
A sound that we hear in a natural setting allows us to identify the sound source and localize it in space. The two aspects
can be disrupted independently as shown in a study of 15 patients with focal right-hemispheric lesions. Four patients were
normal in sound recognition but severely impaired in sound localization, whereas three other patients had difficulties in
recognizing sounds but localized them well. The lesions involved the inferior parietal and frontal cortices, and the superior
temporal gyrus in patients with selective sound localization deficit; and the temporal pole and anterior part of the fusiform,
inferior and middle temporal gyri in patients with selective recognition deficit. These results suggest separate cortical
processing pathways for auditory recognition and localization.
Electronic Publication 相似文献
60.
Ermanno Ciccone Daniela Pende Massimo Vitale Luca Nanni Carolina Di Donato Cristina Bottino Luigia Morelli Oriane Viale Antonio Amoroso Alessandro Moretta Lorenzo Moretta 《European journal of immunology》1994,24(4):1003-1006
The surface expression of given HLA class I alleles protects target cells from lysis mediated by natural killer (NK) clones specific for these (or related) alleles. We could define two groups of NK clones specifically recognizing either Cw4 and related C alleles (“group 1”) or Cw3 and related C alleles (“group 2”), respectively. Monoclonal antibodies (mAb) to class I molecules should interfere with the interaction between NK receptors and class I molecules, thus resulting in lysis of protected target cells. However, none of the numerous available mAb to class I molecules had this effect. Therefore, we attempted to select new mAb on the basis of their ability to induce lysis of Cw4- or Cw3-protected lymphoblastoid cell lines by “group 1” or “group 2” NK clones, respectively. From mice immunized with phytohemagglutinin (PHA)-activated lymphocytes expressing either Cw3 or Cw4 alleles, two mAb were selected, the 6A4 (IgG1) and the A6-136 (IgM), on the basis of their ability to induce lysis of protected target cell. Both mAb immunoprecipitated molecules which, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gave two bands of 45 and 12 kDa, typical of the class I heavy chain and β2 microglobulin, respectively. It has been proposed (but not proven), that self major histocompatibility complex class I molecules protect normal cells from autologous NK cell lysis. Thus, we used the 6A4 and A6-136 mAb to assess this possibility directly. Cw4-specific (“group 1”) and Cw3-specific (“group 2”) NK clones were isolated from donors expressing the corresponding (or related) protective C alleles. None of these clones lysed autologous PHA-induced blasts, used as target cells. However, addition of the F(ab′)2 of 6A4 mAb or the A6-136 mAb resulted in lysis of autologous target cells by “group 1” or “group 2” NK clones, respectively. These data provide direct evidence that the expression of class I molecules protects normal cells from lysis by autologous NK cells. 相似文献