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991.
Lisa DiAndreth Nandita Krishnan Jessica L. Elf Sarah Cox Carla Tilchin Munei Nthulana 《AIDS care》2020,32(6):744-748
ABSTRACTIn South Africa, high attrition rates throughout the care continuum present major barriers to controlling the HIV epidemic. Mobile health (mHealth) interventions may provide innovative opportunities for efficient healthcare delivery and improving retention in care. In this formative research, we interviewed 11 patients and 28 healthcare providers in North West Province, South Africa, to identify perceived benefits, concerns and suggestions for a future mHealth program to deliver HIV Viral Load and CD4 Count test results directly to patients via mobile phone. Thematic analysis found that reduced workload for providers, reduced wait times for patients, potential expanded uses and patient empowerment were the main perceived benefits of an mHealth program. Perceived concerns included privacy, disseminating distressing results through text messages and patients’ inability to interpret results. Participants felt that an mHealth program should complement face-to-face interactions and educational information to interpret results is needed. Providers identified logistical considerations and suggested protocols be developed. An mHealth program to deliver HIV test results directly to patients could mitigate multiple barriers to care but needs to be tested for efficacy. Concerns identified by patients and providers must be addressed in designing the program to successfully integrate with health facility workflow and ensure its sustainability. 相似文献
992.
Inhaled Rho kinase inhibitors are potent and selective vasodilators in rat pulmonary hypertension 总被引:3,自引:0,他引:3
Nagaoka T Fagan KA Gebb SA Morris KG Suzuki T Shimokawa H McMurtry IF Oka M 《American journal of respiratory and critical care medicine》2005,171(5):494-499
We have found in chronically hypoxic rats that acute intravenous administration of the Rho kinase inhibitor Y-27632 nearly normalizes the pulmonary hypertension (PH) but has no pulmonary vascular selectivity. In this study, we tested if oral or inhaled Y-27632 would be an effective and selective pulmonary vasodilator in hypoxic PH. Although acute oral Y-27632 caused a marked and sustained decrease in mean pulmonary arterial pressure (MPAP), it also decreased mean systemic arterial pressure (MSAP). In contrast, 5 minutes of inhaled Y-27632 decreased MPAP without reducing MSAP. The hypotensive effect of inhaled Y-27632 on hypoxic PH was greater than that of inhaled nitric oxide, and the effect lasted for at least 5 hours. Inhaled fasudil, another Rho kinase inhibitor, caused selective MPAP reductions in monocrotaline-induced PH and in spontaneous PH in fawn-hooded rats, as well as in chronically hypoxic rats. These results suggested that inhaled Y-27632 was more effective than inhaled nitric oxide as a selective pulmonary vasodilator in hypoxic PH, and that Rho kinase-mediated vasoconstriction was also involved in the other models of PH. Inhaled Rho kinase inhibitors might be useful for acute vasodilator testing in patients with PH, and future work should evaluate their efficacy in the long-term treatment of PH. 相似文献
993.
Characterization of primitive hematopoietic cells from patients with dyskeratosis congenita 总被引:1,自引:0,他引:1
Goldman FD Aubert G Klingelhutz AJ Hills M Cooper SR Hamilton WS Schlueter AJ Lambie K Eaves CJ Lansdorp PM 《Blood》2008,111(9):4523-4531
Dyskeratosis congenita (DC) is an inherited bone marrow (BM) failure syndrome associated with mutations in telomerase genes and the acquisition of shortened telomeres in blood cells. To investigate the basis of the compromised hematopoiesis seen in DC, we analyzed cells from granulocyte colony-stimulating factor mobilized peripheral blood (mPB) collections from 5 members of a family with autosomal dominant DC with a hTERC mutation. Premobilization BM samples were hypocellular, and percentages of CD34+ cells in marrow and mPB collections were significantly below values for age-matched controls in 4 DC subjects. Directly clonogenic cells, although present at normal frequencies within the CD34+ subset, were therefore absolutely decreased. In contrast, even the frequency of long-term culture-initiating cells within the CD34+ DC mPB cells was decreased, and the telomere lengths of these cells were also markedly reduced. Nevertheless, the different lineages of mature cells were produced in normal numbers in vitro. These results suggest that marrow failure in DC is caused by a reduction in the ability of hematopoietic stem cells to sustain their numbers due to telomere impairment rather than a qualitative defect in their commitment to specific lineages or in the ability of their lineage-restricted progeny to execute normal differentiation programs. 相似文献
994.
Identification of a fibrin-independent platelet contractile mechanism regulating primary hemostasis and thrombus growth 总被引:1,自引:0,他引:1
A fundamental property of platelets is their ability to transmit cytoskeletal contractile forces to extracellular matrices. While the importance of the platelet contractile mechanism in regulating fibrin clot retraction is well established, its role in regulating the primary hemostatic response, independent of blood coagulation, remains ill defined. Real-time analysis of platelet adhesion and aggregation on a collagen substrate revealed a prominent contractile phase during thrombus development, associated with a 30% to 40% reduction in thrombus volume. Thrombus contraction developed independent of thrombin and fibrin and resulted in the tight packing of aggregated platelets. Inhibition of the platelet contractile mechanism, with the myosin IIA inhibitor blebbistatin or through Rho kinase antagonism, markedly inhibited thrombus contraction, preventing the tight packing of aggregated platelets and undermining thrombus stability in vitro. Using a new intravital hemostatic model, we demonstrate that the platelet contractile mechanism is critical for maintaining the integrity of the primary hemostatic plug, independent of thrombin and fibrin generation. These studies demonstrate an important role for the platelet contractile mechanism in regulating primary hemostasis and thrombus growth. Furthermore, they provide new insight into the underlying bleeding diathesis associated with platelet contractility defects. 相似文献
995.
996.
997.
Tasaka S Richer SE Mizgerd JP Doerschuk CM 《American journal of respiratory and critical care medicine》2002,166(1):53-60
This study tested the hypothesis that very late antigen (VLA)-4 mediates CD18-independent neutrophil emigration into the airspaces induced by either Streptococcus pneumoniae, a stimulus that induces primarily CD18-independent neutrophil emigration, or Escherichia coli, toward which only 20-30% of the total number of neutrophils emigrate through CD18-independent pathways. In wild-type (WT) mice, VLA-4 expression was less on neutrophils that emigrated into the airspaces than on circulating neutrophils. Vascular cell adhesion molecule-1 (VCAM-1) mRNA, the major endothelial cell ligand for VLA-4, increased more in E. coli than in S. pneumoniae pneumonia. VCAM-1 protein expression was not detected in capillaries, the major site of neutrophil emigration. Neutrophil emigration during E. coli or S. pneumoniae pneumonia was similar in mice given antibodies against both CD18 and VLA-4 compared with mice given the anti-CD18 antibody and a control antibody. However, in hematopoietically reconstituted mice with both WT and CD18-deficient neutrophils in their blood, the migration of CD18-deficient neutrophils in response to S. pneumoniae was slightly but significantly less in animals pretreated with the anti-VLA-4 antibody than in those receiving a control antibody. These data suggest that VLA-4 plays a small role in CD18-independent neutrophil emigration, but the majority of CD18-independent neutrophil emigration induced by bacteria in the lungs occurs through VLA-4-independent mechanisms. 相似文献
998.
999.
Granot Z Silverman E Friedlander R Melamed-Book N Eimerl S Timberg R Hales KH Hales DB Stocco DM Orly J 《Endocrine research》2002,28(4):375-386
The Steroidogenic Acute Regulatory (StAR) protein is a mitochondrial protein required for the transport of cholesterol substrate to the P450scc enzyme located in the inner mitochondrial membranes of steroid producing cells. This study suggests that the acute regulation of the rodent StAR gene in the ovary is mediated by two factors, C/EBPbeta and GATA-4. Once translated, the StAR precursor protein is either imported into the mitochondria, or it is rapidly degraded in the cytosol. We predicted that in order to perpetuate StAR activity cycles, imported StAR should turn over rapidly to avoid a potentially harmful accumulation of the protein in sub-mitochondrial compartments. Pulse-chase experiments in metabolically labeled cells showed that: (a) the turnover rate of mature mitochondrial StAR protein (30 kDa) is much faster (t(1/2) = 4-5 h) than that of other mitochondrial proteins; (b) dissipation of the inner membrane potential (-delta psi) by carbonyl cyanide m-chlorophenylhydrazone (mCCCP) accelerates the mitochondrial degradation of StAR; (c) unexpectedly, the mitochondrial degradation of StAR is inhibited by MG132 and lactacystin, but not by epoxomicin. Furthermore, StAR degradation becomes inhibitor-resistant two hours after import. Therefore, these studies suggest a bi-phasic route of StAR turnover in the mitochondria. Shortly after import, StAR is degraded by inhibitor-sensitive protease(s) (phase I), whereas at later times, StAR turnover proceeds to completion through an MG132-resistant proteolytic activity (phase II). Collectively, this study defines StAR as a unique protein that can authentically be used to probe multiple proteolytic activities in mammalian mitochondria. 相似文献
1000.
Sarah Liskowich Kathryn Walker Nicolas Beatty Peter Kapusta Shari McKay Vivian R. Ramsden 《Canadian family physician Médecin de famille canadien》2015,61(7):e324-e330