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51.
Mildred E. Phillips Ursula A. Rother K. O. Rother G. Jeanette Thorbecke 《Immunology》1969,17(2):315-321
Allogeneic and congenic post-irradiation chimeras were produced by bone marrow transfer from C′5 active donor mice into C′5 defective recipients. During the first 4 weeks after transfer many of the chimeras contained haemolytic complement activity in their sera. B6AF1→A chimeras developed higher levels of activity than did B10D2 (new line)→ B10D2 (old line).
Spleen tissue, but not liver tissue, taken from the chimeric animals during this time period incorporated [14C]amino acid into MuB1 as demonstrated by autoradiography of immunoelectrophoretic patterns, suggesting localization of the active donor cells in the spleen rather than in the liver. Formation of donor-type IgG remained demonstrable for a more extended period after induction of chimerism than formation of MuB1.
A transplantable hepatoma in C57L/J, a C′5 active mouse strain, also incorporated [14C]amino acid into MuB1.
相似文献52.
Horak F Stübner UP Zieglmayer R Harris AG 《The Journal of allergy and clinical immunology》2002,109(6):956-961
BACKGROUND: Unlike many antihistamines, desloratadine can reduce nasal congestion in patients with seasonal allergic rhinitis (SAR). OBJECTIVE: We compared the effects of 5 mg of desloratadine and placebo on nasal airflow and SAR symptoms, including nasal congestion, in response to grass pollen in an allergen-exposure unit. METHODS: In a randomized, double-blind, placebo-controlled, crossover trial, 47 subjects with histories of SAR received desloratadine or placebo every morning for 7 days and, after a 10-day washout period, were crossed over to the other treatment arm for 7 days. Subjects underwent a 6-hour allergen exposure on day 7 of each treatment period. Nasal airflow and nasal secretion weights were measured before and every 30 minutes during allergen exposure; SAR symptoms (including nasal congestion) were scored before exposure and every 15 minutes thereafter. RESULTS: Nasal obstruction, as measured by nasal airflow, was less severe with desloratadine than with placebo (P <.02). Individual and combined SAR symptom severity scores, including nasal congestion and sneezing, were significantly lower with desloratadine than with placebo (all P < or =.003). Within 30 minutes of allergen exposure, less severely decreased nasal airflow (P <.02), less nasal secretions (P <.001), and less severe symptoms, including nasal congestion (P <.002), rhinorrhea, and sneezing, occurred with desloratadine compared with placebo, and this continued throughout (0-6 hours) allergen exposure. Desloratadine was well tolerated, with an adverse event profile similar to that of placebo. CONCLUSION: In subjects with allergen-induced SAR symptoms, desloratadine significantly reduced the severity of nasal obstruction and accompanying complaints of nasal congestion and other SAR symptoms compared with the effects of placebo. 相似文献
53.
A comparison of murine and human immunoproteomes of Helicobacter pylori validates the preclinical murine infection model for antigen screening
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Bumann D Holland P Siejak F Koesling J Sabarth N Lamer S Zimny-Arndt U Jungblut PR Meyer TF 《Infection and immunity》2002,70(11):6494-6498
Preclinical mouse infection models are widely used for Helicobacter vaccine development, but how well such models mimic important aspects of human infections is unknown. A comparison of Helicobacter pylori immunoproteomes of infected mice with previously reported patient data reveals a high agreement in the antigens recognized, suggesting that H. pylori in vivo protein composition and recognition by the host immune system are comparable in mice and humans. Murine Helicobacter models may thus be valid to screen antigens for human vaccination. 相似文献
54.
Few studies have examined the associations between environmental conditions and developing infant emotionality or the differential susceptibility to those conditions. The present longitudinal study aims to make a contribution to close that gap. We analyzed whether positive emotionality, negative emotionality/irritability, and withdrawal/fear at the end of the first year of life are predictable from preceding caregiver's depression/anxiety, social support, and sensitivity in the interaction with the infant while controlling for antecedent states of emotionality. Furthermore, the question of whether associations between maternal characteristics and subsequent fear are stronger in the subgroup of infants high in irritability as opposed to those who are low in irritability was investigated. Subjects were 101 healthy firstborn infants and their primary caregivers. Assessments were conducted at infant ages of 4, 8, and 12 months. Depression, anxiety, and the social support of the caregiver were assessed by questionnaire. Sensitivity in the caregiver-infant interaction was assessed by behavior observations within the scope of home visits. Temperament characteristics were observed in standardized laboratory episodes. Whereas negative emotionality and withdrawal/fear were significantly predictable from the maternal characteristics, no predictability could be shown for developing positive emotionality. There were indications of a stronger association between the maternal characteristics and developing withdrawal/fear in irritable infants. 相似文献
55.
Analysis of gene expression patterns in small amounts of human ventricular myocardium by a multiplex RNase protection assay 总被引:3,自引:0,他引:3
C. Mittmann Ursula Münstermann Joachim Weil Michael Böhm Stefan Herzig Christoph Nienaber Thomas Eschenhagen 《Journal of molecular medicine (Berlin, Germany)》1998,76(2):133-140
End-stage human heart failure is associated with changes in expression of steady-state messenger RNA (mRNA) levels. These
changes correspond to alterations in protein levels and myocardial function and may have clinical implications regarding etiology,
clinical state, or prognosis. However, analysis of mRNA levels in endomyocardial biopsies can be accomplished only by the
quantitative polymerase chain reaction, which is difficult to standardize. The aim of the study was to evaluate whether the
RNase protection assay is applicable to measure mRNAs of multiple genes simultaneously in small amounts of ventricular myocardium
comparable to myocardial biopsies. Total RNA was prepared from left ventricular myocardium from terminally failing hearts
with idiopathic (n=9) or ischemic cardiomyopathy (n=7) and from nonfailing control hearts (n=10). mRNA was measured by an optimized RNase protection assay for the β1-adrenoceptor, the stimulatory G protein α-subunit (Gsα), phospholamban, the calcium ATPase of the sarcoplasmic reticulum (SERCA), β-myosin heavy chain (β-MHC), and the atrial natriuretic
peptide (ANP). We extracted 10.7±2.1 μg total RNA from three myocardial biopsies taken in vitro. All of the six genes were
measurable in duplicate in a total of 7 μg RNA. mRNAs of β1-adrenoceptor, phospholamban, and SERCA were lower in failing than in nonfailing myocardium by 50%, 33%, and 42% respectively,
whereas β-MHC and Gsα mRNAs were unchanged. mRNA of ANP was expressed at high levels only in the failing myocardium, providing a highly specific
and sensitive marker for discriminating nonfailing and failing hearts. A direct comparison with ANP and Gsα levels obtained by Northern blot analysis with 7.5 μg total RNA showed a good correlation between the two methods. The RNase
protection assay is thus a suitable method for simultaneous measurements of multiple mRNA levels in human myocardial biopsies.
Changes in mRNA levels closely reflected those identified by other methods using larger amounts of RNA. Increased myocardial
ANP mRNA levels determined by the RNase protection assay may serve as a molecular marker of heart failure.
Received: 12 May 1997 / Accepted: 8 September 1997 相似文献
56.
Gerhard Zingler Gabriele Blum Ursula Falkenhagen Ida Orskov Frits Orskov Jörg Hacker Manfred Ott 《Medical microbiology and immunology》1993,182(1):13-24
Escherichia coli isolates of serotype O6:K5 are the most common causative agents of cystitis and pyelonephritis in adults. To answer the question, as to whether strains of this particular serotype represent one special clonal group, out of a collection of 34 serotype O6:K5 isolates [Zingler et al. (1990) Zentralbl. Bakteriol Mikrobiol Hyg [A] 274:372–381] 15 strains were selected and analyzed in detail. The flagellar (H) antigen and the outer membrane protein (OMP) pattern were determined. Further serum resistance properties and the genetic presence and expression of other virulence factors, including hemolysin, aerobactin, P fimbriae, S/F1C fimbriae and type 1 fimbriae was evaluated. In addition the Xba-Imacrorestriction pattern of ten representative isolates was elaborated and the fimbrial (F) antigen type of the P fimbriae was determined, to obtain the complete O:K:H:F pattern. These analyses could clearly show that the O6:K5 isolates do not represent one clonal group. The XbaI-macrorestriction profiles were heterogeneous and marked differences in the hybridization patterns, using virulence-associated gene probes in Southern hybridization of long-range-separated genomic DNA, were observed among the strains. However, some of strains showed similarities in the genomic profiles, arguing for clonal groupings among the O6:K5 isolates. Interstingly the strains grouped together exhibited the same fimbrial F type that many indicate a coincidence of this phenotypic trait with clonality.In memoriam of Prof. G. Naumann 相似文献
57.
Mice with the scid mutation have a defect in the V(D)J recombinase. In order to
determine whether the SCID product is normally present in mature B cells that do not
have the recombinase activity, scid pre-B cells were fused with myeloma cells. It was
found that in the hybrid cells, a rearrangement test gene was correctly joined
immediately after fusion. The same test gene was aberrantly rearranged in the scid pre-B
cells. Stable hybrids between the scid pre-B and the myeloma cells had lost the
expression of RAG-1 and RAG-2 genes, supporting the previous finding of an inhibitor
of rearrangement in myeloma cells that acts shortly after fusion. Thus, mature B cells
apparently contain the SCID product, the wild type SCID function is not competitively
interfered with by products present in scid pre-B cells, and the SCID product seems not
to be a target for the recombinase inhibitor. 相似文献
58.
Henrik Ewald Ole Mors Tracey Flint Ursula Friedrich Hans Eiberg Torben A. Kruse 《American journal of medical genetics. Part A》1995,60(5):386-392
The long arm of chromosome 11 is one of the most interesting regions in the search for major genes involved in the etiology of manic-depressive illness. Several candidate genes have been identified, including the gene encoding the dopamine D2 receptor, the M1 muscarinic receptor, and porfobillinogen deaminase. Furthermore, different families with co-segregation of psychiatric illness and structural chromosome abnormalities involving regions 11q21, 11q22.3, and 11q25 have been reported. Using narrow as well as broad phenotypic models, conservative genetic parameters, models with dominant or recessive modes of inheritance, and various methods to reduce misclassification, the present study did not find evidence for a major gene causing manic-depressive illness on the long arm of chromosome 11. In the broader phenotypic models multi-point analyses excluded at least 11q14 to 11q23.3, approximately 60 cM, even in one large family. Assuming homogeneity close linkage to DRD2 was excluded for all dominant models, and also in the affecteds-only analyses in the large family alone. © 1995 Wiley-Liss, Inc. 相似文献
59.
60.
Metzler M Strissel PL Strick R Niemeyer C Roettgers S Borkhardt A Harbott J Ludwig WD Stanulla M Schrappe M Reinhardt D Creutzig U Beck JD Rascher W Repp R Langer T 《Genes, chromosomes & cancer》2004,41(3):291-296
Therapy-related acute myeloid leukemia (t-AML) characterized by the t(9;11)(p22;q23) translocation is one of the most frequent secondary malignancies. The timing of the initiation of translocation and of development of the malignant t(9;11) clone during chemotherapy is presently unknown. In the present study, we backtracked bone marrow samples from three children during treatment for acute lymphoblastic leukemia (ALL). Two patients developed a t(9;11)-positive t-AML 19 and 30 months after therapy start, whereas the third patient, diagnosed with a rare t(9;11)-positive ALL, suffered from an ALL relapse 23 months after initial diagnosis. The genomic MLL-MLLT3 (MLL-AF9) fusion site was amplified by a multiplex, nested long-range PCR and used as a clonal marker for quantification of the MLL-MLLT3-positive cells during chemotherapy. The t(9;11)-positive clone was detectable 13 and 18 months after therapy start in both t-AML cases, which was 6-12 months before clinical diagnosis of the secondary malignancy. In the t(9;11)-positive ALL patient, the identical leukemic clone reoccurred during maintenance therapy after a short molecular remission, 8 months before clinically overt ALL relapse. The time course and characteristics of the genomic breakpoints in the present t-AML cases support the hypothesis of translocation formation as a result of defective breakage repair after topoisomerase II cleavage. 相似文献