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41.
42.
Leslee J. Shaw Romalisa Miranda-Peats Piotr Slomka John Friedman Sean W. Hayes Daniel S. Berman Gary V. Heller Marcin Dada William E. Boden Paul Casperson Robert A. O’Rourke Ronald Schwartz William S. Weintraub David J. Maron Spencer King Koon Teo Pamela Hartigan 《Journal of nuclear cardiology》2006,13(5):685-698
Background Stress gated myocardial perfusion single photon emission computed tomography (gSPECT) is increasingly used before and after
intercurrent therapeutic intervention and is the basis for ongoing evaluation in the Department of Veterans Affairs clinical
outcomes utilizing revascularization and aggressive drug evaluation (COURAGE) trial.
Methods and Results The COURAGE trial is a North American multicenter randomized clinical trial that enrolled 2287 patients to aggressive medical
therapy vs percutaneous coronary intervention plus aggressive medical therapy. Three COURAGE nuclear substudies have been
designed. The goals of substudy 0 are to examine the diagnostic accuracy of the extent and severity of inducible ischemia
at baseline in COURAGE patients compared with patient symptoms and quantitative coronary angiography and to explore the relationship
between inducible ischemia and the benefit from revascularization when added to medical therapy. Substudy 1 will correlate
the extent and severity of provocative ischemia with the frequency, quality, and instability of recurrent symptoms in postcatheterization
patients. Substudy 2 (n _ 300) will examine the usefulness of sequential gSPECT monitoring 6 to 18 months after therapeutic
intervention. Together, these nuclear substudies will evaluate the role of gSPECT to determine the effectiveness of aggressive
risk-factor modifications, lifestyle interventions, and anti-ischemic medical therapies with or without revascularization
in reducing patients’ ischemic burdens.
Conclusions The unfolding of evidence on the application of gSPECT in trials such as COURAGE defines a new era for nuclear cardiology.
We hope the evidence that emerges from the COURAGE trial will further establish the role of nuclear imaging in the evidence-based
management of patients with stable coronary disease.
The COURAGE trial was supported by the Cooperative Studies Program of the Department of Veterans Affairs Office of Research
and Development in collaboration with the Canadian Institutes of Health Research. Unrestricted research grants were obtained
from Merck & Co; Pfizer Pharmaceuticals; Bristol-Myers Squibb Medical Imaging; Astellas Pharma; Kos Pharmaceuticals; Data
Scope; Astra Zeneca Pharmaceuticals; Astra-Zeneca-Canada; Schering-Plough Coorporation, Ltd; Sanofi-Aventis, Inc; First Horizon;
and GE Healthcare. All industrial funding for this trial was directed through the Department of Veterans Affairs. Additional
funding for this substudy was provided by grants to the Department of Veterans Affairs and Canadian Institutes of Health Research
from Astellas Pharma and Bristol-Myers-Squibb Medical Imaging. 相似文献
43.
Daniel P Potaczek Anetta Undas Magdalena Celinska-Lowenhoff Andrew Szczeklik 《Blood coagulation & fibrinolysis》2006,17(1):35-38
To evaluate whether the interleukin-6 (IL-6) -174 G/C polymorphism might alter the effects of micronized fenofibrate or simvastatin therapy on inflammatory markers, we measured IL-6, C-reactive protein, CD40 ligand, adhesion molecules, P-selectin and monocyte chemoattractant protein-1 in hypercholesterolemic patients both before and after a 30-day treatment. Serum IL-6 levels were significantly higher in patients with the GC or CC genotypes (P=0.04). The presence of the C allele was associated with greater absolute reduction of IL-6 levels (P=0.04) following fenofibrate treatment. There was no significant association between the -174 G/C IL-6 polymorphism and the effects of simvastatin treatment. A relationship between the -174 G/C IL-6 polymorphism and the anti-inflammatory action of fenofibrate reported might be useful in the optimization of the treatment regimen in patients receiving this class of drugs. 相似文献
44.
Background
In order to reduce systematic errors (such as language bias) and increase the precision of the summary treatment effect estimate, a comprehensive identification of randomised controlled trials (RCT), irrespective of publication language, is crucial in systematic reviews and meta-analyses. We identified trials in the German general health care literature. 相似文献45.
Dnyanesh N Tipre James J Fox Daniel P Holt Gilbert Green Jianhua Yu Martin Pomper Robert F Dannals Frank M Bengel 《Journal of nuclear medicine》2008,49(7):1189-1195
The sympathetic nervous system of the heart plays a key role in the pathophysiology of various cardiac diseases. Small-animal models are valuable for obtaining further insight into mechanisms of cardiac disease and therapy. To determine the translational potential of cardiac neuronal imaging from rodents to humans, we characterized the rat sympathetic nervous system using 3 radiotracers that reflect different subcellular mechanisms: (11)C-meta-hydroxyephedrine (HED), a tracer of neuronal transport showing stable uptake and no washout in healthy humans; (11)C-phenylephrine (PHEN), a tracer of vesicular leakage and intraneuronal metabolic degradation with initial uptake and subsequent washout in humans; and (11)C-epinephrine (EPI), a tracer of vesicular storage with stable uptake and no washout in humans. METHODS: We used a small-animal PET system to study healthy male Wistar rats at baseline, after desipramine (DMI) pretreatment (DMI block), and with DMI injection 15 min after tracer delivery (DMI chase). The rats were kept under general isoflurane anesthesia while dynamic emission scans of the heart were recorded for 60 min after radiotracer injection. A myocardial retention index was determined by normalizing uptake at 40 min to the integral under the arterial input curve. Washout rates were determined by monoexponential fitting of myocardial time-activity curves. RESULTS: At baseline, HED showed high myocardial uptake and sustained retention, EPI showed moderate uptake and significant biphasic washout, and PHEN showed moderate uptake and monoexponential washout. The average (+/- SD) left ventricular retention index for HED, PHEN, and EPI was 7.38% +/- 0.82%/min, 3.43% +/- 0.45%/min, and 4.24% +/- 0.59%/min, respectively; the washout rate for HED, PHEN, and EPI was 0.13% +/- 0.23%/min, 1.13% +/- 0.35%/min, and 0.50% +/- 0.24%/min, respectively. The DMI chase resulted in increased washout only for HED. DMI block decreased myocardial uptake of all tracers by less than 90%. CONCLUSION: Kinetic profiles of HED in the rat myocardium were similar to those of HED in humans, suggesting comparable neuronal transport density. Unlike in humans, however, significant washout of EPI and faster washout of PHEN were encountered, consistent with high intraneuronal metabolic activity, high catecholamine turnover, and reduced vesicular storage. This evidence of increased neuronal activity in rodents has implications for translational studies of cardiac neuronal biology in humans. 相似文献
46.
47.
Age-related bone loss has been associated with high levels of marrow adipogenesis. Estrogens (E2) are known to regulate the differentiation of marrow precursors into osteoblasts, however, their role in bone marrow adipogenesis
remain unknown. E2 regulate adipocyte differentiation in subcutaneous and visceral fat through interaction with other nuclear receptors. This
interaction has not been assessed in bone marrow adipocytes in vivo. In this study, we compared two groups of animals, young
and old, after either oophorectomy (OVX) or oophorectomy plus E2 (OVX + E2) replacement. We found that absence of E2 was associated with higher levels of PPARγ and lower levels of Sirt1 most significantly in the old group. In addition, old
mice responded better to E2 replacement in terms of reducing adipogenesis and PPARγ expression as well as increasing levels of Sirt1 expression. Our
findings represent a new understanding of the role of E2 in age-related bone loss, which could be mediated through the regulation of Sirt1 expression within the bone marrow. In addition,
this evidence suggests that old individuals may show a better response to E2 administration in terms of reverting the high levels of marrow fat seen in age-related bone loss. 相似文献
48.
49.
Eric Y. T. Chan Daniel K. Ng Chung-hong Chan Ka-li Kwok Pok-yu Chow Josephine M. Cheung Suk-yu Leung 《Sleep & breathing》2009,13(1):59-63
Background and objective The purpose of this study is to assess whether Chinese children with high apnea–hypopnea index (AHI) are sleepier by a modified Epworth Sleepiness Scale (ESS).
Materials and methods Records were retrospectively reviewed. We included children who were between 3 and 12 years old, admitted for overnight polysomnogram
because of suspected obstructive sleep apnea syndrome (OSAS). A modified ESS was used to assess excessive daytime sleepiness
(EDS) of the children.
Results One hundred ninety-two Chinese children were included. Children with high AHI, defined as AHI > 5.0, were sleepier than children with AHI less than or equal
to 5. After adjustment by age, gender, and obesity, children with high AHI remained significantly sleepier. Modified ESS was
significantly correlated with AHI (rho = 0.124, 95% CI = 0.004–0.281). Modified ESS score of >8 was the best cutoff point
with the sensitivity and specificity of 0.29 and 0.91, respectively. The odds ratio of children with modified ESS > 10 having
high AHI was 4.231 (95%CI = 1.248 to 14.338) and children with modified ESS > 8 had the highest odds ratio, 4.295(95%CI = 1.66
to 11.1), of having high AHI.
Conclusion
Chinese children with high AHI appear to be sleepier than children with low AHI. Children with suspected OSAS and high modified ESS,
i.e., ESS > 8, had significantly higher odds ratio of having high AHI. Increased sleepiness is a specific but not a sensitive
symptom in snoring children with high AHI. Screening for EDS in snoring children may help us identify those with high AHI
and prioritize the management of those children.
All authors worked and the study was carried out in Kwong Wah Hospital in Hong Kong. There was no conflict of interest and
no specific source of funding for the study. 相似文献