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991.
Sutcliffe AG Saunders K McLachlan R Taylor B Edwards P Grudzinskas G Leiberman B Thornton S 《Fertility and sterility》2003,79(3):512-516
OBJECTIVE: To investigate the possibility that children born after ICSI were at increased risk for neurodevelopmental delay. DESIGN: Retrospective case-control study. SETTING: IVF clinic. PATIENT(S): Fifty-eight singleton children born after ICSI and 38 normally conceived singleton children (controls), matched for relevant sociodemographic characteristics, from Australia and 208 case-patients and 221 controls from the United Kingdom. MAIN OUTCOME MEASURE(S): Antenatal and perinatal, and sociodemographic characteristics; physical health, including congenital abnormalities; and neurodevelopment by using the Griffiths scales of mental development. RESULT(S): Eighty-five percent of case-patients and 96% controls were assessed at a mean age of 13 months. Neurodevelopmental scores were similar in all children. Perinatal outcome was similar, apart from more caesarean sections in the case-patients. Rates of congenital anomalies were similar (5.6% among case-patients vs. 5.7% among controls). Children from fathers with oligozoospermia showed no extra problems. Children born after ICSI in the United Kingdom and Australia were similar. CONCLUSION(S): Children conceived after ICSI did not differ from their naturally conceived peers in physical health or development at ages up to 15 months. 相似文献
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995.
The placebo needle, is it a valid and convincing placebo for use in acupuncture trials? A randomised, single-blind, cross-over pilot trial 总被引:4,自引:0,他引:4
The issue of what constitutes an effective and realistic acupuncture placebo control has been a continuing problem for acupuncture research. In order to provide an effective placebo, the control procedure must be convincing, visible and should mimic, in all respects, apart from a physiological effect, the real active treatment. The 'Streitberger' needle might fulfil these criteria and this paper reports on a validation study. This was a single-blind, randomised, cross-over pilot study. Patients were drawn from the orthopaedic hip and knee, joint replacement waiting list. Intervention consisted of either 2 weeks of treatment with real acupuncture followed by 2 weeks on placebo, or vice versa. The prime outcome was a needle sensation questionnaire and there was a range of secondary outcomes. Thirty-seven patients were randomised and completed treatment. Groups were well balanced at baseline. No significant differences between groups or needle types were found for any of the sensations measured. Most patients were unable to discriminate between the needles by penetration; however, nearly 40% were able to detect a difference in treatment type between needles. No major differences in outcome between real and placebo needling could be found. The fact that nearly 40% of subjects did not find that the two interventions were similar, however, raises some concerns with regard to the wholesale adoption of this instrument as a standard acupuncture placebo. Further work on inter-tester reliability and standardisation of technique is highly recommended before we can be confident about using this needle in further studies. 相似文献
996.
Ponec M Weerheim A Lankhorst P Wertz P 《The Journal of investigative dermatology》2003,120(4):581-588
Culturing of normal human keratinocytes at the air-liquid interface results in the formation of fully differentiated epidermis under in vitro conditions. Although the reconstructed epidermis shows a close resemblance to native tissue, there are still some differences in the stratum corneum lipid profile and intercellular lipid organization. As ceramides belong to one of the major stratum corneum lipid classes, the aim of this study was to characterize this fraction in more detail. For this purpose, individual ceramide fractions were isolated by column chromatography and characterized by a combination of nuclear magnetic resonance spectroscopy, high-performance thin-layer chromatography, and gas chromatography. The results of this study show that in both the native and reconstructed human epidermis the extractable ceramide fraction contains, in addition to the well known acylceramides (EOS, EOH), a new acylceramide in which the omega-O-acylhydroxyacid is amide-linked to phytosphingosine (EOP). The same three sphingoid base moieties (S, P, H) are also found in ceramides with amide-linked nonhydroxy and alpha-hydroxyacids. Whereas the same types of ceramides were present in both tissues, some differences in their fatty acid profiles have been found. In reconstructed epidermis the content of linoleic acid in all three acylceramides fraction was significantly lower; the ceramide(NS) fraction was enriched in short fatty acids and the ceramide(AS) fraction was enriched in long chain alpha-hydroxyacids. These differences together with a lower content of free fatty acids may explain the differences between native and reconstructed tissue in stratum corneum lipid organization observed earlier by X-ray diffraction. 相似文献
997.
Nasir K Tandri H Rutberg J Tichnell C Spevak P Crossan J Baughman KL Kasper EK Tomaselli GF Berger R Calkins H 《Pacing and clinical electrophysiology : PACE》2003,26(10):1955-1960
Treatment of arrhythmogenic right ventricular dysplasia (ARVD) is mostly based on the prevention of sudden cardiac death that results from arrhythmias. A clinical history suggestive of ARVD requires careful evaluation including electrophysiological study. The potential ability to identify those patients who will have inducible VT with electrophysiological study will enable better risk stratification and selection of vulnerable patients for electrophysiologically guided therapy. The purpose of the study was to evaluate the predictive ability of signal-averaged electrocardiography (SAECG) to predict inducibility of VT in patients with ARVD. The patient population consisted of 31 ARVD patients diagnosed with McKenna's criteria who underwent electrophysiological study. Electrophysiological study was considered positive if sustained monomorphic VT was induced. The sensitivity, specificity, and predictive accuracy of various SAECG criteria for inducibility of sustained monomorphic VT were also calculated. Twenty-one patients had inducible VT. The filtered QRS duration (fQRS), duration of signal <40 uV (LAS40), and root mean square voltage in the last 40 ms of QRS duration (RMS40) in ARVD patients induced versus noninduced were 122 +/- 21 and 103 +/- 8 ms (P=0.007), 45 +/- 20 and 28 +/- 14 ms (P=0.02), 19 +/- 19 and 32 +/- 22 uV (0.03), respectively. The ejection fractions were comparable in both groups. fQRS duration > or =110 ms had sensitivity of 91%, specificity of 90%, and a total predictive accuracy of 90% in predicting inducibility of VT in these patients. Filtered QRS duration on SAECG is predictive of electrophysiological study outcome in ARVD. Further studies will be needed to determine if SAECG results can predict the development of ventricular arrhythmias during follow-up. 相似文献
998.
Safety studies done with neotame, a sweetener with intense taste, demonstrate that changes in bodyweight (BW) and BW gain (BWG) are due to reduced food consumption (FC) rather than toxicity. When offered a choice, rats preferred basal diet to diet with relatively low concentrations of neotame. When no choice was available, rats ate less as concentrations increased, demonstrating reduced palatability. Changes in dietary concentrations of neotame resulted in changes in FC. The maximum tolerable doses (MTDs) in rats, dogs, and mice were due to decreases in BWG secondary to poor palatability of diets when neotame concentrations exceeded approximately 35,000 ppm. Concentrations were increased as animals grew to maintain constant dosing on a "mg/kg bw/day" basis. Food conversion efficiency (FCE) was not changed in rats during periods of active growth. The only consistent findings across safety studies were reductions in BW, BWG, and FC with no dose-response in rats, mice, and dogs. In definitive safety studies, there were no adverse findings related to neotame treatment from clinical observations, physical examinations, water consumption, or clinical pathology evaluations; nor was there morbidity, mortality, organ toxicity, macroscopic or microscopic postmortem findings. Analysis of data from long-term studies in Sprague-Dawley rats support the conclusion that changes in FC alone can cause the observed changes in BWG in neotame studies when changes are scaled allometrically [Regul. Toxicol. Pharmacol. (2003)]. Consequently, BW parameters are not appropriate endpoints for setting no-observed-effect levels (NOELs) for neotame. 相似文献
999.
Horne MK Figg WD Arlen P Gulley J Parker C Lakhani N Parnes H Dahut WL 《Pharmacotherapy》2003,23(3):315-318
STUDY OBJECTIVE: To evaluate the frequency of venous thromboembolism (VTE) in patients with advanced androgen-independent prostate cancer who were treated with docetaxel alone or in combination with thalidomide. DESIGN: Retrospective analysis of a randomized phase II trial. SETTING: National Institutes of Health clinical research center. PATIENTS: Seventy men, aged 50-80 years, with advanced androgen-independent prostate cancer. INTERVENTION: Each patient received either intravenous docetaxel 30 mg/m2/week for 3 consecutive weeks, followed by 1 week off, or the combination of continuous oral thalidomide 200 mg every evening plus the same docetaxel regimen. This 4-week cycle was repeated until there was evidence of excessive toxicity or disease progression. MEASUREMENTS AND MAIN RESULTS: None of 23 patients who received docetaxel alone developed VTE, whereas 9 of 47 patients (19%) who received docetaxel plus thalidomide developed VTE (p=0.025). CONCLUSION: The addition of thalidomide to docetaxel in the treatment of prostate cancer significantly increases the frequency of VTE. Clinicians should be aware of this potential complication when adding thalidomide to chemotherapeutic regimens. 相似文献
1000.
We report here a pancreatic cancer drug therapy utility of a gene involved in Down's syndrome. Single Minded 2 gene (SIM2) from Down's Syndrome Critical Region was expressed in pancreatic cancer-derived cell lines as well as in tumor tissues, but not in the normal pancreas. A related member of the SIM family, SIM1, did not show similar specificity. Inhibition by antisense technology of one of the isoforms of SIM2, the short-form (SIM2-s) expression in the CAPAN-1 pancreatic cancer cell line, caused a pronounced growth inhibition and induced cell death through apoptosis. The specificity of antisense was inferred from inhibition of SIM2-s mRNA but not the related members of SIM family. In view of the high mortality rate of pancreatic cancer patients, these findings have important implications for the future of pancreatic cancer treatment. 相似文献