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101.
Several indices are available to assess left ventricular (LV) function. Although ejection fraction (EF) is widely used, it has many limitations. An assessment of LV longitudinal function should be therefore provided as it precedes the impairment of EF. In this context, speckle tracking derived global longitudinal strain is the gold standard but S’ velocity of mitral annulus (by pulsed tissue Doppler) and mitral annular plane systolic excursion (by M-mode) represent more than simple surrogates. LV diastolic assessment should be oriented not to the simple classification of transmitral patterns (E/A ratio and E velocity deceleration time) but to non-invasive estimation of LV filling pressures. This can be mainly obtained from E/e’ ratio, with additional calculation of other measurements such as pulmonary flow atrial reverse velocity, systolic pulmonary arterial pressure and left atrial volume index. This comprehensive assessment could also be useful to differentiate heart failure with reduced and preserved EF in particular. 相似文献
102.
STAT3 mediates hepatic hepcidin expression and its inflammatory stimulation 总被引:17,自引:0,他引:17 下载免费PDF全文
Verga Falzacappa MV Vujic Spasic M Kessler R Stolte J Hentze MW Muckenthaler MU 《Blood》2007,109(1):353-358
Hepcidin is a key iron-regulatory hormone produced by the liver. Inappropriately low hepcidin levels cause iron overload, while increased hepcidin expression plays an important role in the anemia of inflammation (AI) by restricting intestinal iron absorption and macrophage iron release. Its expression is modulated in response to body iron stores, hypoxia, and inflammatory and infectious stimuli involving at least in part cytokines secreted by macrophages. In this study we established and characterized IL6-mediated hepcidin activation in the human liver cell line Huh7. We show that the proximal 165 bp of the hepcidin promoter is critical for hepcidin activation in response to exogenously administered IL6 or to conditioned medium from the monocyte/macrophage cell line THP-1. Importantly, we show that hepcidin activation by these stimuli requires a STAT3 binding motif located at position -64/-72 of the promoter. The same STAT binding site is also required for high basal-level hepcidin mRNA expression under control culture conditions, and siRNA-mediated RNA knockdown of STAT3 strongly reduces hepcidin mRNA expression. These results identify a missing link in the acute-phase activation of hepcidin and establish STAT3 as a key effector of baseline hepcidin expression and during inflammatory conditions. 相似文献
103.
Marco A. Arruda MD PhD Vincenzo Guidetti MD Federica Galli PhD Regina C.A.P. Albuquerque MD MSci Marcelo E. Bigal MD PhD 《Headache》2010,50(6):973-980
(Headache 2010;50:973‐980) Background.— Migraine aggregates within families. Nonetheless the familial aggregation of chronic daily headaches (CDH) and of episodic headaches of different frequencies has been very poorly studied. Accordingly herein we test the hypothesis that frequency of primary headaches aggregates in the family. Methods.— Sample consisted of 1994 children (5‐12 years) identified in the population. Validated questionnaires were used to interview the parents. Crude and adjusted prevalences of low‐frequency (1‐4 headache days/month), intermediate‐frequency (5‐9 days/month), high‐frequency (10‐14 headache days/month), and CDH (15 or more headache days/month) in children were calculated as a function of headaches in the mother. Results.— Frequency of headaches in the mother predicted frequency of headaches in the children; when the mother had low frequency headaches, the children had an increased chance to have low or intermediate headache frequency (relative risk = 1.4, 1.2‐1.6) but not CDH. When the mother had CDH, risk of CDH in the children was increased by almost 13‐fold, but the risk of infrequent headaches was not increased. In multivariate models, headaches in the children were independently predicted by headaches in the mother (P < .001); headache frequency in the children was also predicted by frequency in the mother (P < .001). Conclusions.— Frequency of headaches in children is influenced by frequency of headaches in the mother and seems to aggregate in families. Future studies should focus on the determinants of headache aggregation, including genetic and non‐genetic factors. 相似文献
104.
Delphine S. Tuot Laura C. Plantinga Chi-yuan Hsu Regina Jordan Nilka Ríos Burrows Elizabeth Hedgeman Jerry Yee Rajiv Saran Neil R. Powe for the Centers for Disease Control Chronic Kidney Disease Surveillance Team 《Clinical journal of the American Society of Nephrology》2011,6(8):1838-1844
Summary
Background and objectives
Awareness of chronic kidney disease (CKD) among providers and patients is low. Whether clinical cues prompt recognition of CKD is unknown. We examined whether markers of kidney disease that should trigger CKD recognition among providers are associated with higher individual CKD awareness.Design, setting, participants, & measurements
CKD awareness was assessed in 1852 adults with an estimated GFR <60 ml/min per 1.73 m2 using 1999 to 2008 National Health and Nutrition Examination Survey data. CKD awareness was a “yes” answer to “Have you ever been told you have weak or failing kidneys?” Participants were grouped by distribution of the following abnormal markers of CKD: hyperkalemia, acidosis, hyperphosphatemia, elevated blood urea nitrogen, anemia, albuminuria, and uncontrolled hypertension. Odds of CKD awareness associated with each abnormal marker and groupings of markers were estimated by multivariable logistic regression.Results
Among individuals with kidney disease, only those with albuminuria had greater odds of CKD awareness (adjusted odds ratio, 4.0, P < 0.01) than those without. Odds of CKD awareness increased with each additional manifested clinical marker of CKD (adjusted odds ratio, 1.3, P = 0.05). Nonetheless, 90% of individuals with two to four markers of CKD and 84% of individuals with ≥5 markers of CKD were unaware of their disease.Conclusions
Although individuals who manifest many markers of kidney dysfunction are more likely to be aware of their CKD, their CKD awareness remains low. A better understanding of mechanisms of awareness is required to facilitate earlier detection of CKD and implement therapy to minimize associated complications. 相似文献105.
Carvalho CM Andrade MC Xavier SS Mangia RH Britto CC Jansen AM Fernandes O Lannes-Vieira J Bonecini-Almeida MG 《The American journal of tropical medicine and hygiene》2003,68(6):683-691
Severe chronic damage to the heart and gastrointestinal tract in patients with Chagas' disease are often observed 10-20 years after the acute phase. The course of long-lasting infection with the Colombian strain of Trypanosoma cruzi was studied in seven rhesus monkeys infected for 15-19 years. Subpatent parasitemia was detected in all studied animals, using hemoculture (two of seven), artificial xenodiagnosis (three of seven), and a polymerase chain reaction PCR (six of six). High titers of specific IgG antibody to T. cruzi persisted throughout the chronic phase of infection. Abnormal electrocardiographic (three of six) and echocardiographic (one of six) patterns detected in the T. cruzi-infected monkeys were possibly related to parasite-triggered myocardial damage. The results suggest that rhesus monkeys experimentally infected with T. cruzi, besides reproducing the acute phase of Chagas' disease, also develop chronic chagasic cardiomyopathy. 相似文献
106.
Giannattasio C Failla M Hennig M Hollweck R Laurent S Mallion JM Reid J Safar M Bond G Zanchetti A Mancia G 《Journal of hypertension》2005,23(3):557-562
INTRODUCTION: The European Lacidipine Study on Atherosclerosis (ELSA) has been planned to investigate the effect of reduction in office and ambulatory blood pressure by lacidipine versus atenolol on carotid artery wall thickness in mild to moderate essential hypertensive patients with no metabolic abnormalities. One prespecified sub-study of ELSA focused on measurements of arterial distensibility in the carotid as well as in the radial artery to determine the relationship of functional arterial properties with office versus ambulatory blood pressure (BP) values as well as the correspondence between functional and structural arterial alterations. METHODS: The sub-study was conducted on 124 patients recruited in four centres (Monza-Milan, Paris, Grenoble and Glasgow). BP was measured both by a mercury sphygmomanometer and by 24-h ambulatory monitoring. Common carotid artery wall thickness was measured by certified sonographers as described in the main study. Common carotid and radial artery distensibility were obtained by echotracking techniques, which allowed to relate changes in arterial diameter with systo-diastolic BP changes. RESULTS: Carotid artery wall distensibility showed (1) a negative correlation with office and more so 24-h average systolic BP (r = -0.45 and -0.58, P < 0.008 and 0.001) but not with office or 24-h diastolic BP) and (2) a negative correlation with the corresponding wall thickness (r = -0.47, P < 0.005). In contrast, at the radial artery level distensibility and thickness showed no correlation with each other and with BP. Carotid (but not radial) artery distensibility also correlated with ambulatory systolic BP variability but the correlation was lost after adjustment for age and mean BP values. CONCLUSION: These data suggest that stiffening of large elastic artery is reflected more by ambulatory than office BP elevations, systolic BP being much more important than diastolic. Alterations of large elastic arteries function is related to structural wall changes. Functional and structural properties of middle-size muscle arteries are independent of BP. 相似文献
107.
AIM: To investigate efficacy and safety of cetuximab combined with two chemotherapy regimens in patients with unresectable metastatic colorectal cancer (mCRC). METHODS: Randomized patients received cetuximab with 5-fluorouracil (5-FU), folinic acid (FA) and oxaliplatin (FOLFOX) 6 (arm A, n = 74) or 5-FU, FA and irinotecan (FOLFIRI) (arm B, n = 77). KRAS mutation status was determined retrospectively in a subset of tumors (n = 117). RESULTS: No significant difference was found between treatment arms A and B ... 相似文献
108.
109.
Menno van Gameren Maarten Witsenburg Johanna J M Takkenberg Derize Boshoff Luc Mertens Anton M van Oort Dani?l de Wolf Matthias Freund Narayanswani Sreeram Regina B?kenkamp Melle D Talsma Marc Gewillig 《European heart journal》2006,27(22):2709-2715
AIMS: Stenting has become an established interventional cardiology procedure for congenital heart disease. Although most stent procedures are completed successfully, complications may occur. This multicentre study evaluated early complications after stenting in patients with congenital heart disease, including potential risk factors. METHODS AND RESULTS: In this combined Dutch-Belgian retrospective study, 309 consecutive patients had undergone 366 catheterizations and received 464 stents in 13 different anatomical positions (418 sites). Seventy-two stenting-related complications (19%) occurred, of which 24 (5.7%) were major. Seven procedure-related deaths were documented (2.3%). Stent malpositioning and embolization were most common (7.7%). The use of non-premounted stents tended to be associated with higher complication rates. Centre inexperience with stenting and stenting of native vs. post-surgical stenosis tended to be associated with increased major complication rates. CONCLUSION: After stenting, complications are common for congenital heart disease. The vast diversity of stenotic sites combined with relatively small patient populations makes these procedures sensitive to complications. Combining operator experience may reduce the risks of stenting in congenital heart disease. The availability of premounted stents for greater vessel diameters will likely reduce incidences of stent migration and embolization. 相似文献
110.
Krücken J Dkhil MA Braun JV Schroetel RM El-Khadragy M Carmeliet P Mossmann H Wunderlich F 《Infection and immunity》2005,73(1):436-443
Testosterone induces a lethal outcome in otherwise self-healing blood-stage malaria caused by Plasmodium chabaudi. Here, we examine possible testosterone effects on the antimalaria effectors spleen and liver in female C57BL/6 mice. Self-healing malaria activates gating mechanisms in the spleen and liver that lead to a dramatic reduction in trapping activity, as measured by quantifying the uptake of 3-mum-diameter fluorescent polystyrol particles. However, testosterone delays malaria-induced closing of the liver, but not the spleen. Coincidently, testosterone causes an approximately 3- to 28-fold depression of the mRNA levels of nine malaria-responsive genes, out of 299 genes tested, only in the liver and not in the spleen, as shown by cDNA arrays and Northern blotting. Among these are the genes encoding plasminogen activator inhibitor (PAI1) and hydroxysteroid sulfotransferase (STA2). STA2, which detoxifies bile acids, is suppressed 10-fold by malaria and an additional 28-fold by testosterone, suggesting a severe perturbation of bile acid metabolism. PAI1 is protective against malaria, since disruption of the PAI1 gene results in partial loss of the ability to control the course of P. chabaudi infections. Collectively, our data indicate that the liver rather than the spleen is a major target organ for testosterone-mediated suppression of resistance against blood-stage malaria. 相似文献