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851.
c-kit+ precursors support postinfarction myogenesis in the neonatal, but not adult, heart 总被引:1,自引:0,他引:1
SA Jesty MA Steffey FK Lee M Breitbach M Hesse S Reining JC Lee RM Doran AY Nikitin BK Fleischmann MI Kotlikoff 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(33):13380-13385
We examined the myogenic response to infarction in neonatal and adult mice to determine the role of c-kit(+) cardiovascular precursor cells (CPC) that are known to be present in early heart development. Infarction of postnatal day 1-3 c-kit(BAC)-EGFP mouse hearts induced the localized expansion of (c-kit)EGFP(+) cells within the infarct, expression of the c-kit and Nkx2.5 mRNA, myogenesis, and partial regeneration of the infarction, with (c-kit)EGFP(+) cells adopting myogenic and vascular fates. Conversely, infarction of adult mice resulted in a modest induction of (c-kit)EGFP(+) cells within the infarct, which did not express Nkx2.5 or undergo myogenic differentiation, but adopted a vascular fate within the infarction, indicating a lack of authentic CPC. Explantation of infarcted neonatal and adult heart tissue to scid mice, and adoptive transfer of labeled bone marrow, confirmed the cardiac source of myogenic (neonate) and angiogenic (neonate and adult) cells. FACS-purified (c-kit)EGFP(+)/(αMHC)mCherry(-) (noncardiac) cells from microdissected infarcts within 6 h of infarction underwent cardiac differentiation, forming spontaneously beating myocytes in vitro; cre/LoxP fate mapping identified a noncardiac population of (c-kit)EGFP(+) myocytes within infarctions, indicating that the induction of undifferentiated precursors contributes to localized myogenesis. Thus, adult postinfarct myogenic failure is likely not due to a context-dependent restriction of precursor differentiation, and c-kit induction following injury of the adult heart does not define precursor status. 相似文献
852.
Tikhonoff V Staessen JA Kuznetsova T Thijs L Hasenkamp S Bäumer V Stolarz K Seidlerová J Filipovský J Nikitin Y Peleska J Kawecka-Jaszcz K Casiglia E Brand-Herrmann SM Brand E;European Project On Genes in Hypertension 《Journal of hypertension》2008,26(2):244-250
OBJECTIVE: Previous studies found significant association of hypertension and hypertension-related phenotypes with genetic variation in SAH (Spontaneously hypertensive rat-clone A-Hypertension-associated). We sought independent confirmation of these findings in the European Project On Genes in Hypertension. METHODS AND RESULTS: We randomly recruited 2603 relatives from 560 families and 31 unrelated subjects from six European populations (mean age 38.8 +/- 15.7 years; 52.1% women). We measured systolic/diastolic blood pressure (mean, 122.4/76.6 mmHg), body mass index (24.9 kg/m2), triceps skinfold (1.7 cm), waist-to-hip ratio (0.83 units), serum total and high-density lipoprotein (HDL) cholesterol (5.14 and 1.33 mmol/l), serum triglycerides (1.95 mmol/l) and blood glucose (4.90 mmol/l). We genotyped the G-1606A and -962del/ins polymorphisms. In all subjects, the allele frequencies were 11.8 and 29.5% for -1606A and -962del, respectively. Lewontin's D' was 0.97 (P < 0.0001). Haplotype frequencies were 58.8% for -1606G plus -962ins, 29.5% for -1606G plus -962del, and 11.7% for -1606A plus -962ins. Both before and after adjustment for covariates, none of the phenotype-genotype associations approached statistical significance. Our study had 80% power to detect on two-sided tests (P = 0.05), effect sizes of 1.8/1.3 mmHg for systolic/diastolic blood pressure, 0.52 kg/m2 for body mass index, 0.01 units for the waist-to-hip ratio, 0.96 mm for the triceps skinfold, 0.13 and 0.05 mmol/l for total and HDL cholesterol, 0.18 mmol/l for serum triglycerides, and 0.11 mmol/l for blood glucose. The family-based analyses did not reveal population stratification (P > or = 0.67). CONCLUSION: The evidence supporting an association of hypertension or hypertension-related phenotypes with the SAH gene remains equivocal in human studies. 相似文献
853.
Christos V Bourantas Nikolay P Nikitin Huan P Loh Elena I Lukaschuk Nassar Sherwi Ramesh de Silva Ann C Tweddel Mohamed F Alamgir Kenneth Wong Sanjay Gupta Andrew L Clark John GF Cleland 《Journal of cardiovascular magnetic resonance》2011,13(1):53
Background
Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) can provide unique data on the transmural extent of scar/viability. We assessed the prevalence of dysfunctional myocardium, including partial thickness scar, which could contribute to left ventricular contractile dysfunction in patients with heart failure and ischaemic heart disease who denied angina symptoms.Methods
We invited patients with ischaemic heart disease and a left ventricular ejection fraction < 50% by echocardiography to have LGE CMR. Myocardial contractility and transmural extent of scar were assessed using a 17-segment model.Results
The median age of the 193 patients enrolled was 70 (interquartile range: 63-76) years and 167 (87%) were men. Of 3281 myocardial segments assessed, 1759 (54%) were dysfunctional, of which 581 (33%) showed no scar, 623 (35%) had scar affecting ≤50% of wall thickness and 555 (32%) had scar affecting > 50% of wall thickness. Of 1522 segments with normal contractile function, only 98 (6%) had evidence of scar on CMR. Overall, 182 (94%) patients had ≥1 and 107 (55%) patients had ≥5 segments with contractile dysfunction that had no scar or ≤50% transmural scar suggesting viability.Conclusions
In this cohort of patients with left ventricular systolic dysfunction and ischaemic heart disease, about half of all segments had contractile dysfunction but only one third of these had > 50% of the wall thickness affected by scar, suggesting that most dysfunctional segments could improve in response to an appropriate intervention. 相似文献854.
Nikitin IuP Voevoda MI Simonova GI 《Vestnik Rossi?sko? akademii meditsinskikh nauk / Rossi?skaia akademiia meditsinskikh nauk》2012,(1):66-74
In Siberia and in the Far East region overall incidence of diabetes mellitus is somewhat lower than in the European part of the country, though these indices reduplicate on average in 10-15 years. The prevalence of both diabetes (both types) and metabolic syndrome among indigenous mongoloid population is lower than among Caucasian. 相似文献
855.
856.
Effects of topiramate on migraine frequency and cortical excitability in patients with frequent migraine 总被引:1,自引:0,他引:1
Artemenko AR Kurenkov AL Filatova EG Nikitin SS Kaube H Katsarava Z 《Cephalalgia : an international journal of headache》2008,28(3):203-208
We studied the excitability of the visual and motor cortex in 36 patients with frequent migraine without aura (30 women, mean age 38.6 ± 10.0 years) before and after treatment with topiramate (100 mg/day) using transcranial magnetic stimulation. Treatment with topiramate resulted in reduction of both headache frequency (12.0 ± 1.3 to 5.8 ± 3.2 migraine days per month; P = 0.004) and cortical excitability: motor cortex thresholds increased on the right side from 43.8 ± 7.5% to 47.7 ± 9.2% ( P = 0.049) and on the left side from 43.4 ± 7.0% to 47.2 ± 9.6% ( P = 0.047), and phosphene thresholds increased from 58.9 ± 11.1% to 71.2 ± 11.2% ( P = 0.0001). Reduction of headache frequency correlated inversely with an increase of visual thresholds and did not correlate with motor thresholds. The effect of topiramate in migraine prevention is complex and can not be explained simply by inhibition of cortical excitability. 相似文献
857.
de Silva R Loh H Rigby AS Nikitin NP Witte KK Goode K Bhandari S Nicholson A Clark AL Cleland JG 《The American journal of cardiology》2007,100(2):273-279
Our aim was to determine the prevalence, morbidity, and mortality associated with the presence of significant renal artery stenosis (RAS) in patients with chronic heart failure (HF), and to explore the use of angiotensin-converting enzyme (ACE) inhibitors and diuretics in this population during a 3-year follow-up period. We identified 97 patients with significant renal dysfunction (RD, defined as a calculated glomerular filtration rate of <60 ml/min) and 38 patients without RD, with ejection fractions of <40%. A stenosis of >50% using magnetic resonance angiography of the renal arteries was used to define significant RAS. Seventy-three (54%) patients had significant RAS of >or=1 artery. Mean follow-up time was 37.3 (+/- 7.9) months. Compared with patients with no significant RAS, these patients were on higher doses of diuretics, lower doses of ACE inhibitors, had prolonged hospital admissions, were admitted with exacerbation of HF, and had a higher mortality (p = 0.007 for mortality). In conclusion, RAS is common in patients with chronic HF, especially among patients with RD and is a predictor of a poor clinical outcome. Interventional trials on renal revascularization are underway that contain subsets of patients with HF that may provide evidence on how best to manage RAS in this setting. 相似文献
858.
The upper tentacle of the snail, bearing the olfactory organ, produces complex movements when the snail explores a new environment.
Tentacle trajectories were reconstructed in the presence and absence of odors using two simultaneous video recordings. Reconstructions
showed that in the absence of odor, snails constantly scanned the surrounding space with the extended tentacles. Presentation
of an odor elicited rapid flexion, independent of the odor concentration, accompanied by concentration-dependent tentacle
contractions. Activation of identified motoneuron MtC3 is known to elicit tentacle contraction. Recordings made in semi-intact
preparations showed that the dynamics and duration of the spike activity of MtC3 produced in response to odors correlated
with the degree of tentacle contraction in response to odors. These data suggest that the central motoneuron MtC3, which triggers
tentacle contraction, is involved in controlling the margins of the scanning field. Slow contraction or extension of the tentacle,
associated with the level of MtC3 activity, may operate to tune the snail's investigative behavior to the conditions of the
sensory environment.
__________
Translated from Zhurnal Vysshei Nervnoi Deyatel'nosti imeni I. P. Pavlova, Vol. 54, No. 5, pp. 655–665, September–October,
2004. 相似文献
859.
Potapov AA Iusupova MM Tenedieva VD Nikitin AG Nosikov VV 《Zhurnal voprosy ne?rokhirurgii imeni N. N. Burdenko》2012,76(3):90-95
The paper analyses the published data about association of polymorphic gene markers of different bioactive agents (interleukins, angiotensin convertase, catechol-O-methyltransferase, dopamine receptors etc.) with traumatic brain injury. Analysis of the entire pool of data concerning clinical and experimental studies of association of different polymorphic markers of candidate genes with outcome of traumatic brain injury allows to conclude that IL 1alpha and IL 1beta, IL 6, catechol-O-methyltransferase, angiotensin convertase, D2 dopamine receptors in fact play important role in neuroinflammatory response to injury and recovery of the brain ant its functions. Moreover presence or absence of certain polymorphic gene markers differentially influence separate pathogenetic mechanisms of brain injury (e.g., severity of brain edema, cerebral blood flow, cognitive functions). Consequently each of the investigated genes contributes in outcome after traumatic brain injury. 相似文献
860.
T. I. Arefieva T. L. Krasnikova A. V. Potekhina N. U. Ruleva P. I. Nikitin T. I. Ksenevich B. G. Gorshkov M. V. Sidorova Zh. D. Bespalova N. B. Kukhtina S. I. Provatorov E. A. Noeva E. I. Chazov 《Inflammation research》2011,60(10):955-964