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161.
Glucose Ingestion Attenuates Interleukin-6 Release from Contracting Skeletal Muscle in Humans 总被引:8,自引:1,他引:8
Mark A. Febbraio Adam Steensberg Charlotte Keller Rebecca L. Starkie Henning B. Nielsen Peter Krustrup Peter Ott Niels H. Secher Bente K. Pedersen 《The Journal of physiology》2003,549(2):607-612
To examine whether glucose ingestion during exercise affects the release of interleukin-6 (IL-6) from the contracting limb, seven men performed 120 min of semi-recumbent cycling on two occasions while ingesting either 250 ml of a 6.4 % carbohydrate (GLU trial) or sweet placebo (CON trial) beverage at the onset of, and at 15 min intervals throughout, exercise. Muscle biopsies obtained before and immediately after exercise were analysed for glycogen and IL-6 mRNA expression. Blood samples were simultaneously obtained from a brachial artery and a femoral vein prior to and during exercise and leg blood flow was measured by thermodilution in the femoral vein. Net leg IL-6 release, and net leg glucose and free fatty acid (FFA) uptake, were calculated from these measurements. The arterial IL-6 concentration was lower ( P < 0.05 ) after 120 min of exercise in GLU, but neither intramuscular glycogen nor IL-6 mRNA were different when comparing GLU with CON. However, net leg IL-6 release was attenuated ( P < 0.05 ) in GLU compared with CON. This corresponded with an enhanced ( P < 0.05 ) glucose uptake and a reduced ( P < 0.05 ) FFA uptake in GLU. These results demonstrate that glucose ingestion during exercise attenuates leg IL-6 release but does not decrease intramuscular expression of IL-6 mRNA. 相似文献
162.
Bruce Guthrie Tom Love Rebecca Kaye Margaret MacLeod Jim Chalmers 《The British journal of general practice》2008,58(550):311-317
BACKGROUND: The Shipman Inquiry recommended mortality rate monitoring if it could be 'shown to be workable' in detecting a future mass murderer in general practice. AIM: To examine the effectiveness of cumulative sum (CUSUM) charts, cross-sectional Shewhart charts, and exponentially-weighted, moving-average control charts in mortality monitoring at practice level. DESIGN OF STUDY: Analysis of Scottish routine general practice data combined with estimation of control chart effectiveness in detecting a 'murderer' in a simulated dataset. METHOD: Practice stability was calculated from routine data to determine feasible lengths of monitoring. A simulated dataset of 405,000 'patients' was created, registered with 75 'practices' whose underlying mortality rates varied with the same distribution as case-mix-adjusted mortality in all Scottish practices. The sensitivity of each chart to detect five and 10 excess deaths was examined in repeated simulations. The sensitivity of control charts to excess deaths in simulated data, and the number of alarm signals when control charts were applied to routine data were estimated. RESULTS: Practice instability limited the length of monitoring and modelling was consequently restricted to a 3-year period. Monitoring mortality over 3 years, CUSUM charts were most sensitive but only reliably achieved >50% successful detection for 10 excess deaths per year and generated multiple false alarms (>15%). CONCLUSION: At best, mortality monitoring can act as a backstop to detect a particularly prolific serial killer when other means of detection have failed. Policy should focus on changes likely to improve detection of individual murders, such as reform of death certification and the coroner system. 相似文献
163.
Rachael Goodman-Williams Rebecca Campbell Dhruv B. Sharma Steven J. Pierce Hannah Feeney Giannina Fehler-Cabral 《Journal of trauma & dissociation》2019,20(3):288-303
ABSTRACTHundreds of thousands of previously untested sexual assault kits (SAKs) have been uncovered in police property storage facilities across the United States, representing a national failure in institutional response to sexual assault. Faced with this discovery, jurisdictions must now decide if and how they should test these kits. Some stakeholders have suggested prioritizing kits for testing by victim, offender, or assault characteristics, based on the belief that these characteristics can predict the likely utility of DNA testing. However, little research has examined the empirical merits of such prioritization. To address this gap in the literature and inform SAK testing policies, we randomly sampled 900 previously untested SAKs from Detroit, MI. The sampled SAKs were submitted for DNA testing, and eligible DNA profiles were entered into Combined DNA Index System (CODIS), the federal DNA database. Police records associated with each SAK were coded for victim, offender, and assault characteristics, and logistic regression analyses were conducted to test whether these characteristics predict which SAKs yield DNA profiles that match (“hit”) to other criminal offenses in CODIS. Testing this sample of previously-untested SAKs produced a substantial number of CODIS hits, but few of the tested variables were significant predictors of CODIS hit rate. These findings suggest that testing all previously-unsubmitted kits may generate information that is useful to the criminal justice system, while also potentially addressing the institutional betrayal victims experienced when their kits were ignored. 相似文献
164.
James B. Harris MD Richard C. Ahrens MD Gary Milavetz PharmD Linda Annis Rebecca Ries BA Connie Hendricker RRT 《The Journal of allergy and clinical immunology》1990,85(6):1043-1049
Inhaled beta-agonists can produce bronchodilatation and reduce airway hyperreactivity in patients with asthma. Using these two measures, we compared inhaled bitolterol (three puffs, 1110 micrograms), albuterol (two puffs, 180 micrograms), and placebo administered by metered-dose inhaler in a blinded, crossover study of 40 subjects with chronic asthma. On each study day, subjects underwent histamine challenges at 1 1/2 hours before, and 1/2, 2, 4, 6, and 8 hours after inhaling one of the three test-drug treatments. Both drugs produced significant bronchodilatation at 30 minutes through 4 hours and significant effects on airway reactivity at 30 minutes through 2 hours (p less than 0.05). Bitolterol also produced small but significant bronchodilator effects at 6 hours and effects on airway reactivity at 4 hours (p less than 0.05). Effects of bitolterol on airway reactivity diminished significantly more slowly than effects of albuterol in subjects with baseline provocative concentration causing a 20% fall in FEV1 greater than or equal to 1.0 mg/ml of histamine (half-life of biologic effect 1.37 versus 0.92 hours; p less than 0.05) but not in subjects with baseline provocative concentration causing a 20% fall in FEV1 less than or equal to 1.0 mg/ml (half-life of biologic effect of 1.01 versus 1.00 hours; p greater than 0.05). 相似文献
165.
Tuluc M Horn A Inniss S Thomas R Zhang PJ Khurana JS 《Annals of clinical and laboratory science》2005,35(1):97-99
Glomus tumors are tumors of pericytic origin and are usually found in the distal extremities. Glomus tumors have rarely been reported in viscera. The authors report a glomus tumor of the colon that caused rectal bleeding in a 40-yr-old man and was biopsied and excised endoscopically. The histology and immunohistochemical profile of the tumor are described and the literature on visceral glomus tumors is reviewed. 相似文献
166.
167.
168.
Ethan M. Shevach Rebecca S. McHugh Ciriaco A. Piccirillo Angela M. Thornton 《Immunological reviews》2001,182(1):58-67
Summary: Depletion of the minor (∼10%) subpopulation of CD4+ T cells that co-expresses CD25 (interleukin (IL)-2 receptor α-chain) by thymectomy of neonates on the third day of life or by treatment of adult CD4+ T cells with anti-CD25 and complement results in the development of organ-specific autoimmunity. Autoimmune disease can be prevented by reconstitution of the animals with CD4+ CD25+ cells. CD4+ CD25+ -mediated protection of autoimmune gastritis does not require the suppressor cytokines IL-4, IL-10, or transforming growth factor (TGF)-β. Mice that express a transgenic T-cell receptor (TCR) derived from a thymectomized newborn that recognizes the gastric parietal cell antigen H/K ATPase all develop severe autoimmune gastritis very early in life. CD4+ CD25+ T cells are also powerful suppressors of the activation of both CD4+ and CD8+ T cells in vitro . Suppression is mediated by a cell contact-dependent, cytokine-independent T–T interaction. Activation of CD4+ CD25+ via their TCR generates suppressor effector cells that are capable of non-specifically suppressing the activation of any CD4+ or CD8+ T cell. Activation of suppressor effector function is independent of co-stimulation mediated by CD28/CTLA-4 interactions with CD80/CD86. We propose that CD4+ CD25+ T cells recognize organ-specific antigens, are recruited to sites of autoimmune damage where they are activated by their target antigen, and then physically interact with autoreactive CD4+ or CD8+ effector cells to suppress the development of autoimmune disease. 相似文献
169.
Barbara Wedel Rebecca R. Boyles James W. Putney Jr Gary S. Bird 《The Journal of physiology》2007,579(3):679-689
We have investigated the nature of the Ca2+ entry supporting [Ca2+ ]i oscillations in human embryonic kidney (HEK293) cells by examining the roles of recently described store-operated Ca2+ entry proteins, Stim1 and Orai1. Knockdown of Stim1 by RNA interference (RNAi) reduced the frequency of [Ca2+ ]i oscillations in response to a low concentration of methacholine to the level seen in the absence of external Ca2+ . However, knockdown of Stim1 did not block oscillations in canomical transient receptor potential 3 channel (TRPC3)-expressing cells and did not affect Ca2+ entry in response to arachidonic acid. The effects of knockdown of Stim1 could be reversed by inhibiting Ca2+ extrusion with a high concentration of Gd3+ , or by rescuing the knockdown by overexpression of Stim1. Similarly, knockdown of Orai1 abrogated [Ca2+ ]i oscillations, and this was reversed by use of high concentrations of Gd3+ ; however, knockdown of Orai1 did not affect arachidonic acid-activated entry. RNAi targeting 34 members of the transient receptor potential (TRP) channel superfamily did not reveal a role for any of these channel proteins in store-operated Ca2+ entry in HEK293 cells. These findings indicate that the Ca2+ entry supporting [Ca2+ ]i oscillations in HEK293 cells depends upon the Ca2+ sensor, Stim1, and calcium release-activated Ca2+ channel protein, Orai1, and provide further support for our conclusion that it is the store-operated mechanism that plays the major role in this pathway. 相似文献
170.
Light scattering from cervical cells throughout neoplastic progression: influence of nuclear morphology,DNA content,and chromatin texture 总被引:1,自引:0,他引:1
Drezek R Guillaud M Collier T Boiko I Malpica A Macaulay C Follen M Richards-Kortum R 《Journal of biomedical optics》2003,8(1):7-16
A number of noninvasive fiber optic optical technologies are under development for real-time diagnosis of neoplasia. We investigate how the light scattering properties of cervical cells are affected by changes in nuclear morphology, DNA content, and chromatin texture, which occur during neoplastic progression. We used a Cyto-Savant computer-assisted image analysis system to acquire quantitative nuclear features measurements from 122 Feulgen-thionin-stained histopathologic sections of cervical tissue. A subset of the measured nuclear features was incorporated into a finite-difference time-domain (FDTD) model of cellular light scattering. The magnitude and angular distribution of scattered light was calculated for cervical cells as a function of pathologic grade. The nuclear atypia strongly affected light scattering properties. The increased size and elevated DNA content of nuclei in high-grade lesions caused the most significant changes in scattering intensity. The spatial dimensions of chromatin texture features and the amplitude of refractive index fluctuations within the nucleus impacted both the angular distribution of scattering angles and the total amount of scattered light. Cellular scattering is sensitive to changes in nuclear morphology that accompany neoplastic progression. Understanding the quantitative relationships between nuclear features and scattering properties will aid in the development of noninvasive optical technologies for detection of precancerous conditions. 相似文献