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71.
Feil S Zimmermann P Knorn A Brummer S Schlossmann J Hofmann F Feil R 《Neuroscience》2005,135(3):863-868
Nitric oxide (NO) modulates a variety of processes in the mammalian brain, but the mechanisms of neuronal NO signaling are poorly understood. In the periphery, many effects of NO are mediated via the generation of the second messenger cyclic guanosine-3',5'-monophosphate (cGMP) and activation of the cGMP-dependent protein kinase type I (cGKI). However, previous studies suggested that the expression of cGKI in the nervous system is rather restricted, thus, questioning the functional significance of the cGMP/cGKI pathway as a mediator of NO signaling in the brain. Here we have performed a detailed immunohistochemical study to elucidate the distribution of cGKI in the CNS and eye of the mouse. Expression of cGKI protein was detected not only in the previously described areas (cerebellum, hippocampus, dorsomedial hypothalamus) but also in a number of additional regions, such as medulla, subcommissural organ, cerebral cortex, amygdala, habenulae, various hypothalamic regions, olfactory bulb, pituitary gland, and retina. Immunoblotting with isoform-specific antibodies indicated that the cGKIalpha isoform is prominent in the cerebellum and medulla, whereas the cGKIbeta isoform is predominant in the cortex, hippocampus, hypothalamus, and olfactory bulb. Similar levels of the isoforms were detected in the pituitary gland and eye. Thus, it appears that distinct brain regions express distinct cGKI isoforms that signal via distinct pathways. Together, these results improve our understanding of the cellular and molecular mechanisms of NO/cGMP/cGKI signaling and indicate that the distribution and functional relevance of this pathway in the mammalian brain is broader than previously thought. 相似文献
72.
Marius Schwabenland Henrike Salié Jovan Tanevski Saskia Killmer Marilyn Salvat Lago Alexandra Emilia Schlaak Lena Mayer Jakob Matschke Klaus Püschel Antonia Fitzek Benjamin Ondruschka Henrik E. Mei Tobias Boettler Christoph Neumann-Haefelin Maike Hofmann Angele Breithaupt Nafiye Genc Christine Stadelmann Bertram Bengsch 《Immunity》2021,54(7):1594-1610.e11
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73.
Wallich R Jahraus O Stehle T Tran TT Brenner C Hofmann H Gern L Simon MM 《European journal of immunology》2003,33(3):708-719
Vaccination with recombinant outer surface protein A (OspA) from Borrelia burgdorferi provides excellent antibody-mediated protection against challenge with the pathogen in animal models and in humans. However, the bactericidal antibodies are ineffective in the reservoir host, since OspA is expressed by spirochetes only in the vector, but rarely, if at all, in mammals. Using an artificially generated immune serum (anti-10(8) spirochetes) with high protective potential for prophylactic and therapeutic treatment, we have now isolated from an expression library of B. burgdorferi (strain ZS7) three novel genes, zs7.a36, zs7.a66 and zs7.a68. All three genes are located, together with ospA/B, on the linear plasmid lp54, and are expressed in vitro and in ticks. At least temporarily two of them, ZS7.A36 and ZS7.A66, are also expressed during infection. The respective natural antigens are poorly immunogenic ininfected normal mice but elicited antibodies in Lyme disease patients. We show that recombinant preparations of ZS7.A36, ZS7.A66 and ZS7.A68 induce functional antibodies in rabbits capable of protecting immunodeficient mice against subsequent experimental infection. These findings suggest that all three recombinant antigens represent potential candidates for a "second generation" vaccine to prevent and/or cure Lyme disease. 相似文献
74.
A. Schuster A. Hofmann D. Reinhardt 《Journal of molecular medicine (Berlin, Germany)》1993,71(3):208-213
Summary To evaluate whether pertussis induces the development of allergy, a prospective study was performed in 25 children aged 0.8–12.2 years. The patients underwent allergy diagnostics during pertussis infection and at a follow-up visit 8–14 months later. Diagnostic criteria included the medical history of the patients and their families, a modified skin prick test, measurement of serum IgE and radio-allergosorbent test screening for specific sensitizations. At the time of pertussis, serum IgE concentration in the study group was 62+ 30 kU/ml. At the follow-up visit, there was a significant increase in serum IgE to 137 ± 51 kU/ml, which was also significantly higher than IgE in an age-matched control group. Children at a significantly higher risk for developing IgE increase or new allergic sensitizations were those with a family history of allergy or potentially allergic disease in their personal history. Our results indicate that pertussis may induce IgE production in affected children.Abbreviation SPT
skin prick test
Dedicated to Prof. Dr. N. Zöllner on the occasion of his 70th birthday 相似文献
75.
Detection of Borrelia burgdorferi sensu lato in lesional skin of patients with erythema migrans and acrodermatitis chronica atrophicans by ospA-specific PCR. 总被引:3,自引:4,他引:3
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S E Moter H Hofmann R Wallich M M Simon M D Kramer 《Journal of clinical microbiology》1994,32(12):2980-2988
The aim of this study was to develop a sensitive and specific PCR for the detection of Borrelia burgdorferi DNA. The plasmid-located gene coding for the outer surface protein A (OspA [31-kDa protein]) was used as a target. Nucleotide sequence information from different B. burgdorferi ospA genotypes was used to design primers homologous to different genotypes. The sensitivity of the nested PCR differed from 1 fg to 1 pg of borrelial DNA, depending on the strain analyzed. No cross-reactions with DNA from spirochetes other than B. burgdorferi or with human DNA were observed. A total of 22 skin biopsy samples from patients with erythema migrans (EM [n = 10]) or acrodermatitis chronica atrophicans (ACA [n = 12]) were examined for the presence of B. burgdorferi by nested PCR. Of 22 biopsies, 80% from EM patients and 92% from ACA patients were positive by PCR amplification. By comparison, 50% of the EM patients had elevated B. burgdorferi-specific immunoglobulin M (IgM) and/or IgG antibody levels as tested by enzyme-linked immunosorbent assay (ELISA) using purified B. burgdorferi flagella as antigen. A total of 33% of ACA patients had elevated IgM titers, and all had high IgG titers in their sera. Only 30% of specimens from patients with EM and none from patients with ACA were positive by culture. All culture-positive specimens were also positive by PCR. Thus, the sensitivities of the PCR were 80 and 92%, respectively, for patients with EM and ACA on the basis of the clinical and histopathological diagnoses of Lyme disease. From these results, we conclude that PCR is a suitable method to detect B. burdorferi sensu lato DNA in skin biopsy samples and could be applied as an additional diagnostic tool. 相似文献
76.
This paper presents an evaluation of the inhalation and ingestion doses from exposure to Rn and Rn progeny; an overview of the human and animal health-effects data; estimations of the cancer risks from Rn and Rn-progeny exposures; and suggested limits for Rn concentrations in drinking water and indoor air. We suggest that a rounded Rn-in-water concentration limit of 10,000 pCi/l can be supported by health-effects considerations alone, based on the conservative "tolerance dose" concept and other conservative assumptions regarding lung dose. A practical concentration limit (or action level) of 20,000 pCi/l has been derived by estimations of exposure distributions in the United States and in relation to current U.S. Environmental Protection Agency (EPA) standards for U-tailings-contaminated buildings. Research needed for resolution of the uncertainties in these estimates is suggested. We conclude that before a maximum contaminant level (MCL) for Rn in water can be firmly established, the broader issue of setting the MCL for Rn in indoor air must be addressed. 相似文献
77.
D. Hofmann H. Ecke M. Nietert und M. Langhans 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1987,372(1):849
Zusammenfassung In einer von der DFG unterstützten experimentellen Untersuchung wurde die Vorlast am proximalen Femur nach Implantation verschiedener zementfreier Hüftendoprothesen gemessen. Als Prüfkörper diente ein sogenannter Kunststoffnormfemur. Zuvor waren mit Hilfe der Spannungsoptik die optimalen Applikationspunkte für Dehnungsmessstreifen ermittelt worden. Von den 6 bisher untersuchten Prothesen hatten die PM-Prothese, die bitrochantere Prothese und die Rippensystem-Prothese die höchste Vorlast. Bei der MR-Prothese und der Müller Geradschaftprothese fiel eine gegensinnige Vorspannung auf, während die isoelastische Prothese nur eine geringe Vorlast erzeugte. 相似文献
78.
The metabolism and enterohepatic circulation of deoxycholic acid (DCA), a major secondary bile acid in humans, was simulated using a linear multicompartmental physiologic pharmacokinetic model. The model was similar to that previously reported and used to simulate the metabolism of cholic acid and chenodeoxycholic acid, but differed in two respects: (a) the input of newly formed DCA molecules originated from colonic absorption rather than from de novo hepatic biosynthesis and (b) a new type of transfer coefficient was proposed to describe the movement of DCA molecules from an insoluble, bound compartment to a soluble compartment. Simulations were performed to define the effect of varying fractional colonic absorption (from 0.1 to 0.6) as well as varying fractional formation of DCA from cholic acid (from 0.3 to 1). The simulations indicated that the exchangeable total DCA pool expanded up to 12-fold as fractional colonic absorption was increased from 0.1 to 0.6. The fractional turnover rate of the DCA pool showed a corresponding decrease. Increased conversion of cholic acid to DCA had an effect on DCA pool size that was similar to that resulting from increased colonic fractional absorption. So long as ileal absorption was efficient, the "soluble" colonic pool of DCA remained small relative to other organ pools, and the absorption of unconjugated DCA from the colon was less than 10% of the total DCA absorption from the ileum. It is proposed that the relatively large proportion of DCA in the biliary bile acids of white adults in the Western world as compared with that of most other mammals is attributable to (a) a high fractional absorption of DCA because of a diet relatively low in fiber, (b) the absence of hepatic 7-hydroxylation of DCA, and (c) effective competition by DCA conjugates for active transport by the terminal ileum. 相似文献
79.
Welmoed van Loon Heike Rssig Susen Burock Jrg Hofmann Julian Bernhard Elisabeth Linzbach Domenika Pettenkofer Christian Schnfeld Maximilian Gertler Joachim Seybold Tobias Kurth Frank P. Mockenhaupt 《Emerging infectious diseases》2021,27(7):1931
Within 5 weeks in 2021, B.1.1.7 became the dominant severe acute respiratory syndrome coronavirus 2 lineage at an outpatient testing site in Berlin, Germany. Compared with outpatients with wild-type virus infection, patients with B.1.1.7 had similar cycle threshold values, more frequent sore throat and travel history, and less frequent anosmia/ageusia. 相似文献
80.
Jrg Hofmann Stephanie Kramer Klaus R. Herrlinger Kathrin Jeske Martin Kuhns Sabrina Weiss Rainer G. Ulrich Detlev H. Krüger 《Emerging infectious diseases》2021,27(4):1232
We report molecular evidence of Tula virus infection in an immunocompetent patient from Germany who had typical signs of hantavirus disease. Accumulating evidence indicates that Tula virus infection, although often considered nonpathogenic, represents a threat to human health. 相似文献