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21.
Hage FG Karakus G Luke WD Suwanjutah T Burri MV Nanda NC Aqel RA 《Echocardiography (Mount Kisco, N.Y.)》2008,25(7):784-789
Alcohol-induced septal ablation (AISA) is an accepted treatment for hypertrophic cardiomyopathy (HCM) patients with left ventricular (LV) outflow obstruction who are unresponsive to medical therapy. As left atrial (LA) enlargement has been correlated with increased morbidity and mortality in HCM, we assessed LA volumes and ejection fraction (EF) prior to and after AISA using real time three-dimensional (3D) transthoracic echocardiography (TTE) in 12 patients (9 women; mean age 52 ± 15 years; 11 Caucasian). All patients underwent successful AISA with no complications and their resting left ventricular outflow gradients decreased from 40.5 ± 22.2 to 9.1 ± 17.6 mmHg (P < 0.001) while their gradients with provocation decreased from 126.2 ± 31.7 to 21.8 ± 28.0 mmHg (P < 0.001). All patients showed improvements in their New York Heart Association (NYHA) functional class. Both the LA end-systolic (45.2 ± 12.9 to 37.2 ± 13.7 ml, P < 0.0001) and end-diastolic (79.6 ± 18.9 to 77.1 ± 18.6 ml, P = 0.001) volumes decreased after AISA. The LA EF increased from 43.1 ± 9.0 to 52.5 ± 8.8% (P = 0.001). The increase in LA EF correlated with the decrease in the resting left ventricular outflow gradient (R =−0.647, P = 0.03). In conclusion, 3D echocardiography can be utilized to follow LA function after AISA for HCM. AISA results in clinical improvement in patients with HCM and in improvement of LA EF that is correlated with the decrease in the left ventricular outflow gradient. 相似文献
22.
Platelet-derived growth factor C induces liver fibrosis, steatosis, and hepatocellular carcinoma 总被引:16,自引:0,他引:16
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Campbell JS Hughes SD Gilbertson DG Palmer TE Holdren MS Haran AC Odell MM Bauer RL Ren HP Haugen HS Yeh MM Fausto N 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(9):3389-3394
Members of the platelet-derived growth factor (PDGF) ligand family are known to play important roles in wound healing and fibrotic disease. We show that both transient and stable expression of PDGF-C results in the development of liver fibrosis consisting of the deposition of collagen in a pericellular and perivenular pattern that resembles human alcoholic and nonalcoholic fatty liver disease. Fibrosis in PDGF-C transgenic mice, as demonstrated by staining and hydroxyproline content, is preceded by activation and proliferation of hepatic stellate cells, as shown by collagen, alpha-smooth muscle actin and glial fibrillary acidic protein staining and between 8 and 12 months of age is followed by the development of liver adenomas and hepatocellular carcinomas. The hepatic expression of a number of known profibrotic genes, including type beta1 TGF, PDGF receptors alpha and beta, and tissue inhibitors of matrix metalloproteinases-1 and -2, increased by 4 weeks of age. Increased PDGF receptor alpha and beta protein levels were associated with activation of extracellular regulated kinase-1 and -2 and protein kinase B. At 9 months of age, PDGF-C transgenic mice had enlarged livers associated with increased fibrosis, steatosis, cell dysplasia, and hepatocellular carcinomas. These studies indicate that hepatic expression of PDGF-C induces a number of profibrotic pathways, suggesting that this growth factor may act as an initiator of fibrosis. Moreover, PDGF-C transgenic mice represent a unique model for the study of hepatic fibrosis progressing to tumorigenesis. 相似文献
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E. Burri D. Cisternas A. Villoria A. Accarino A. Soldevilla J.‐R. Malagelada F. Azpiroz 《Neurogastroenterology and motility》2013,25(4):339-e253
Background Using an experimental model of colonic gas infusion, we previously showed that the abdominal walls adapt to its content by an active phenomenon of abdominal accommodation. We now hypothesized that abdominal accommodation is a physiological phenomenon, and aimed to confirm that it can be induced by ingestion of a meal; a secondary aim was to determine whether the response to gut filling is region‐specific. Methods In healthy subjects (n = 24) a nutrient test meal was administered until tolerated at a rate of 50 mL min?1. Electromyographic (EMG) activity of the anterior wall (upper and lower rectus, external and internal oblique) was measured via four pairs of surface electrodes, and EMG activity of the diaphragm via intraluminal electrodes on an esophageal tube. To address the secondary aim, the response to gastric filling was compared with that induced by colonic filling (1440 mL 30 min?1 anal gas infusion; n = 8). Key Results Participants tolerated 927 ± 66 mL of meal (450–1500 mL). Meal ingestion induced progressive diaphragmatic relaxation (EMG reduction by 16 ± 2%; P < 0.01) and selective contraction of the upper abdominal wall (24 ± 2% increase in activity of the upper rectus and external oblique; P < 0.01 for both), with no significant changes in the lower rectus (4 ± 2%) or internal oblique (5 ± 3%). Colonic gas infusion induced a similar response, but with an overall contraction of the anterior wall. Conclusions & Inferences Meal ingestion induces a metered and region‐specific response of the abdominal walls to accommodate the volume load. Abnormal abdominal accommodation could be involved in postprandial bloating. 相似文献
26.
Haran Sivapalan 《International review of psychiatry (Abingdon, England)》2013,25(3):285-288
The portrayal of self-medication and drug use was studied in three films by Martin Scorsese: Raging Bull (1980), Goodfellas (1990) and The Departed (2006). Self-medication using nicotine in Raging Bull, cocaine in Goodfellas and sedatives in The Departed, exhibit mixed portrayals of the self-medication hypothesis. The temporal aspects of the hypothesis and credibility of character psychopathology show variation between the films. Across all films, the selection of particular drugs of choice for certain symptom clusters is consonant with that detailed in the self-medication hypothesis put forward by Khantzian. 相似文献
27.
Water permeability changes studied by 17O nuclear magnetic resonance during differentiation of Friend leukemia cells.
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N Haran Z Malik A Lapidot 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(7):3363-3366
Water permeability of Friend leukemia cells was studied by 17O nuclear magnetic resonance during differentiation induced by dimethyl sulfoxide (Me2SO). While in noninduced cells water permeability was essentially constant during the growth period, in the Me2SO-induced cells there were two distinct periods at which the water permeability was increased by at least an order of magnitude. These periods correspond to approximately one doubling time and 6 days of growth. This change in water permeability is not due to direct interaction of Me2SO with the membrane but must be ascribed to structural changes in the membrane during the course of differentiation. 相似文献
28.
The aim of the study was to explore the effects of 12 weeks daily krill oil supplementation on fasting serum triglyceride (TG) and lipoprotein particle levels in subjects whose habitual fish intake is low and who have borderline high or high fasting serum TG levels (150–499 mg/dL). We hypothesized that Krill oil lowers serum TG levels in subjects with borderline high or high fasting TG levels. To test our hypothesis 300 male and female subjects were included in a double-blind, randomized, multi-center, placebo-controlled study with five treatment groups: placebo (olive oil) or 0.5, 1, 2, or 4 g/day of krill oil. Serum lipids were measured after an overnight fast at baseline, 6 and 12 weeks. Due to a high intra-individual variability in TG levels, data from all subjects in the four krill oil groups were pooled to increase statistical power, and a general time- and dose-independent one-way analysis of variance was performed to assess efficacy. Relative to subjects in the placebo group, those administered krill oil had a statistically significant calculated reduction in serum TG levels of 10.2%. Moreover, LDL-C levels were not increased in the krill oil groups relative to the placebo group. The outcome of the pooled analysis suggests that krill oil is effective in reducing a cardiovascular risk factor. However, owing to the individual fluctuations of TG concentrations measured, a study with more individual measurements per treatment group is needed to increase the confidence of these findings. 相似文献
29.
Recent studies have demonstrated that the serotonergic and noradrenergic systems are functionally and anatomically linked and both systems have been implicated as contributors to the regulation of the phasic release of LH. Consequently, perturbations within the serotonergic system could secondarily affect noradrenergic system activity and result in a loss of phasic LHRH secretion. In the present studies we examined the effects of p-chlorophenylalanine (PCPA) on LH surges and the associated changes which occur in hypothalamic serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) concentrations. We also evaluated the effects of this drug on norepinephrine (NE) and dopamine (DA) initial concentrations, rate constants and turnover rates in the medial preoptic area (MPN), suprachiasmatic nuclei (SCN), paraventricular nuclei (PVN) and median eminence (ME). Seven days after ovariectomy, rats received estradiol (E2) capsules (day 0) and on day 1 some animals also received PCPA (250 mg/kg b. wt., i.p.) while the remainder served as controls. LH surges occurred in control animals but not in PCPA-treated rats on days 2, 3 and 4. PCPA produced a significant decline in 5-HT and 5-HIAA concentrations in all microdissected hypothalamic regions at 09.00 and 15.00 h on day 2. In control rats, there were no significant changes in initial concentrations of NE in the MPN, PVN and ME between 09.00 and 15.00 h with the exception of the SCN where a slight decline had occurred by 15.00 h. NE rate constants and turnover rates increased during the afternoon in controls in the MPN, SCN and ME and declined in the PVN concomitant with LH surges. PCPA had variable effects in suppressing NE initial concentrations depending upon the hypothalamic area studied and the time of day. More importantly, the drug abolished the diurnal rhythm in rate constants observed in controls and consequently, neither the MPN, SCN nor ME showed any increase in NE turnover rates in the afternoon of day 2. In contrast, a significant decline in rate constants and turnover rates occurred in the PVN of both control and PCPA-treated rats during the afternoon of day 2. DA initial concentrations declined in controls between 09.00 and 15.00 h in the MPN and ME but not in the SCN or PVN.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
30.
Chris F. Maher Donald G. Cave Mano V. Haran 《The Australian & New Zealand journal of obstetrics & gynaecology》1994,34(4):389-392
Summary: The Caesarean section rate in consecutive years was decreased from 20.5% to 11.1% of total public deliveries (p< 0.0001). On retrospective analysis the emergency Caesarean section rate decreased from 10.9% to 6.0% (p < 0.0001) and elective Caesarean section rate from 9.6% to 5.1% (p<0.0001) in consecutive years. Interventions which have accounted for the decrease were 3-fold. Firstly, vaginal birth after Caesarean delivery was encouraged, secondly, the active management of labour and thirdly, extensive, regular peer review were introduced as unit policy. The decrease in the Caesarean section rate was not achieved at the expense of the fetus as judged by perinatal mortality rates and 5-minute Apgar scores of less than 7. 相似文献