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991.
McDowell A Valanne S Ramage G Tunney MM Glenn JV McLorinan GC Bhatia A Maisonneuve JF Lodes M Persing DH Patrick S 《Journal of clinical microbiology》2005,43(1):326-334
Although two phenotypes of the opportunistic pathogen Propionibacterium acnes (types I and II) have been described, epidemiological investigations of their roles in different infections have not been widely reported. Using immunofluorescence microscopy with monoclonal antibodies (MAbs) QUBPa1 and QUBPa2, specific for types I and II, respectively, we investigated the prevalences of the two types among 132 P. acnes isolates. Analysis of isolates from failed prosthetic hip implants (n = 40) revealed approximately equal numbers of type I and II organisms. Isolates from failed prosthetic hip-associated bone (n = 6) and tissue (n = 38) samples, as well as isolates from acne (n = 22), dental infections (n = 8), and skin removed during surgical incision (n = 18) were predominately of type I. A total of 11 (8%) isolates showed atypical MAb labeling and could not be conclusively identified. Phylogenetic analysis of P. acnes by nucleotide sequencing revealed the 16S rRNA gene to be highly conserved between types I and II. In contrast, sequence analysis of recA and a putative hemolysin gene (tly) revealed significantly greater type-specific polymorphisms that corresponded to phylogenetically distinct cluster groups. All 11 isolates with atypical MAb labeling were identified as type I by sequencing. Within the recA and tly phylogenetic trees, nine of these isolates formed a cluster distinct from other type I organisms, suggesting a further phylogenetic subdivision within type I. Our study therefore demonstrates that the phenotypic differences between P. acnes types I and II reflect deeper differences in their phylogeny. Furthermore, nucleotide sequencing provides an accurate method for identifying the type status of P. acnes isolates. 相似文献
992.
5-Hydroxytryptamine (5-HT; serotonin)-containing neurones contribute to reflex activation of parasympathetic outflow in a number of species, but the 5-HT receptors mediating these effects have yet to be fully determined. The present experiments demonstrate that central 5-HT7 receptors are involved in the vagal bradycardia evoked during the cardiopulmonary reflex, baroreflexes and the chemoreflex, as well as other autonomic changes caused by these reflexes. The experiments examined the effects of the selective 5-HT7 receptor antagonists SB-269970 and SB-656104 on these reflexes. For the cardiopulmonary reflex, when compared to time-matched vehicle control experiments, intracisternal application of SB-269970 (30–300 μg kg−1 , i.c. ) dose-dependently attenuated the evoked bradycardia. At the highest dose, SB-269970 also attenuated the reflex hypotension and sympathoinhibition. The structurally different 5-HT7 receptor antagonist SB-656104 (100 μg kg−1 , i.c. ) similarly attenuated the reflex bradycardia and hypotension. SB-269970 (100 μg kg−1 , i.c. ) also attenuated the bradycardias evoked by electrical stimulation of aortic nerve afferents and the baroreflex evoked by the pressor response to phenylephrine (3–25 μg kg−1 , i.v. ). The gain of the baroreflex was also significantly attenuated (0.15 ± 0.06 versus 0.34 ± 0.06 ms mmHg−1 ). Finally, SB-269970 (100 μg kg−1 , i.c. ) significantly attenuated both the bradycardia and sympathoexcitation evoked by the chemoreflex. These data indicate that central 5-HT7 receptors play an important facilitatory role in the reflex activation of vagal outflow to the heart. 相似文献
993.
In B-cell non-Hodgkin's lymphoma (NHL), as in other B-cell malignancies, clonal rearrangement of the third complementarity determining region (CDR III) of the immunoglobulin heavy chain gene (IgH) provides a useful marker for the detection of minimal residual disease (MRD) after treatment. To determine the clinical utility of IgH polymerase chain reaction (PCR), we analyzed peripheral blood (PB) and bone marrow (BM) samples from 25 patients with NHL with no PCR detectable chromosomal rearrangement who have undergone autologous bone marrow transplantation (ABMT). Patients with histologic bone marrow infiltration at the time of bone marrow harvest were selected for study since this provided us with diagnostic tissue samples. As an initial strategy DNA was amplified using consensus variable (VH) and joining (JH) region primers. In those cases failing to amplify using consensus region primers, PCR was performed using a panel of VH family-specific framework region 1 (FR1) primers. The clonal products were directly sequenced. From the V-N-D region nucleotide sequences, clone specific probes were constructed and used for subsequent detection of MRD. A clonal PCR product could be PCR amplified and directly sequenced in 18 (72%, 90% confidence intervals 54%-86%) of these 25 patients, 8 with diffuse and 10 with follicular NHL. Eight of these 18 patients have relapsed after ABMT. All had detectable lymphoma cells before relapse and the sequence of the CDR III region at the time of relapse was identical to that obtained at the time of ABMT. All 10 patients who remain in complete remission from 18 to 36 months after ABMT had eradication of PCR detectable lymphoma cells after ABMT, although in three patients PCR detectable MRD was detected early after ABMT. We conclude that sequencing and the use of patient specific IgH CDR III oligonucleotides probes provides a simple and highly reliable method to determine the specificity of the IgH PCR technique. The clinical utility of this technique is demonstrated by the finding that eradication of PCR detectable lymphoma cells in these patients is associated with decreased relapse after ABMT (P = .0002). 相似文献
994.
设计合成了21个1-[2-(取代苯基甲硫基)-2-(2,4-二氟苯基)乙基]-1H-1,2,4-三唑类化合物,其中19个为首次报道。体外抑菌试验表明:所有目标化合物对8种试验真菌均有不同程度的抗菌活性,其中化合物1,2,5对絮状表皮癣菌的活性为硫康唑的512倍以上;化合物5对白色念株菌的活性为硫康唑的32倍;化合物2对申克孢子丝菌的活性为硫康唑的32倍;化合物2,14对新型隐球菌的活性分别为硫康唑的64倍,32倍;化合物1,5对熏烟色曲菌的活性分别为硫康唑的16倍以上。 相似文献
995.
R Tessier N Charpak M Giron M Cristo ZF de Calume JG Ruiz-Peláez 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(9):1444-1450
Aims: This study tested the hypothesis that Kangaroo Mother Care creates a climate in the family, which enhances infants' performance on the developmental quotient scale.
Setting: The largest social security hospital in Colombia with a neonatal intensive care unit.
Subjects: At 12 months of corrected age, 194 families in the Kangaroo Mother Care group and 144 families in the Traditional Care group were available for analysis.
Interventions: Infants were kept 24 h/day in an upright position, in skin-to-skin contact until it was no longer tolerated by the infants. Babies in the Traditional Care were kept in incubators on the Minimal Care Unit until they satisfied the usual discharge criteria.
Outcome measures: The Home Observation for Measurement of the Environment (HOME), Father Involvement and Developmental Quotient (Griffiths) scores.
Results: 1) Kangaroo mothers created a more stimulating context and a better caregiving environment than mothers in the Traditional Care group; 2) this environment was positively correlated to father involvement and 3) the family environment of male infants was most improved by Kangaroo Mother Care.
Conclusion: Kangaroo Mother Care has a positive impact on home environment. The results also suggest, first, that both parents should be involved as direct caregivers in the Kangaroo Mother Care procedure and secondly, that this intervention should be directed more specifically at infants who are more at risk at birth. The Kangaroo Mother Care intervention could be an excellent means to ensure parents' mature involvement in the future of their children. 相似文献
Setting: The largest social security hospital in Colombia with a neonatal intensive care unit.
Subjects: At 12 months of corrected age, 194 families in the Kangaroo Mother Care group and 144 families in the Traditional Care group were available for analysis.
Interventions: Infants were kept 24 h/day in an upright position, in skin-to-skin contact until it was no longer tolerated by the infants. Babies in the Traditional Care were kept in incubators on the Minimal Care Unit until they satisfied the usual discharge criteria.
Outcome measures: The Home Observation for Measurement of the Environment (HOME), Father Involvement and Developmental Quotient (Griffiths) scores.
Results: 1) Kangaroo mothers created a more stimulating context and a better caregiving environment than mothers in the Traditional Care group; 2) this environment was positively correlated to father involvement and 3) the family environment of male infants was most improved by Kangaroo Mother Care.
Conclusion: Kangaroo Mother Care has a positive impact on home environment. The results also suggest, first, that both parents should be involved as direct caregivers in the Kangaroo Mother Care procedure and secondly, that this intervention should be directed more specifically at infants who are more at risk at birth. The Kangaroo Mother Care intervention could be an excellent means to ensure parents' mature involvement in the future of their children. 相似文献
996.
997.
The relationship between the hemorrhagic and antithrombotic properties of low molecular weight heparin in rabbits 总被引:4,自引:0,他引:4
We have compared the hemorrhagic and antithrombotic effects of a low molecular weight (LMW) heparin fraction and standard heparin in rabbits. Similar LMW heparin fractions have antithrombotic effects when tested in animals, but their hemorrhagic effects relative to standard heparin have not been established. Standard porcine mucosal heparin (mol wt 15,000 daltons) was depolymerized by nitrous acid to a low molecular weight fraction (mol wt 4600 daltons). Using equal USP units, the standard and Dep LMW heparin were compared in vitro, ex vivo, and in vivo. In vitro, when diluted in rabbit plasma, the Dep LMW heparin at equivalent anti-Xa activity showed less prolongation of thrombin clotting times or activated partial thromboplastin times. Ex vivo, platelets from rabbits treated with the Dep LMW heparin showed less inhibition of collagen-induced aggregation. The relative hemorrhagic properties of the two heparins were compared in vivo in rabbits using a sensitive blood loss assay, and the antithrombotic properties were compared in a thrombin-induced venous stasis model. By using an optimal threshold heparin dose in each test system, it was possible to demonstrate that equal USP units of Dep LMW heparin caused less blood loss but showed greater antithrombotic activity than standard heparin. 相似文献
998.
999.
Amy E. Ramage Angela R. Laird Simon B. Eickhoff Ashley Acheson Alan L. Peterson Douglas E. Williamson Michael J. Telch Peter T. Fox 《Human brain mapping》2013,34(12):3392-3399
Posttraumatic stress disorder (PTSD) has a well‐defined set of symptoms that can be elicited during traumatic imagery tasks. For this reason, trauma imagery tasks are often employed in functional neuroimaging studies. Here, coordinate‐based meta‐analysis (CBM) was used to pool eight studies applying traumatic imagery tasks to identify sites of task‐induced activation in 170 PTSD patients and 104 healthy controls. In this way, right anterior cingulate (ACC), right posterior cingulate (PCC), and left precuneus (Pcun) were identified as regions uniquely active in PTSD patients relative to healthy controls. To further characterize these regions, their normal interactions, and their typical functional roles, meta‐analytic connectivity modeling (MACM) with behavioral filtering was applied. MACM indicated that the PCC and Pcun regions were frequently co‐active and associated with processing of cognitive information, particularly in explicit memory tasks. Emotional processing was particularly associated with co‐activity of the ACC and PCC, as mediated by the thalamus. By narrowing the regions of interest to those commonly active across multiple studies (using CBM) and developing a priori hypotheses about directed probabilistic dependencies amongst these regions, this proposed model—when applied in the context of graphical and causal modeling—should improve model fit and thereby increase statistical power for detecting differences between subject groups and between treatments in neuroimaging studies of PTSD. Hum Brain Mapp 34:3392–3399, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
1000.