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951.
952.
Yan B Parsons M McKay S Campbell D Infeld B Czajko R Davis SM 《Cerebrovascular diseases (Basel, Switzerland)》2005,19(4):234-238
BACKGROUND: Although acute decreases in total cholesterol (TC) are well documented in myocardial infarction, previous stroke studies have produced conflicting results. The timing of lipid estimation in ischemic stroke is becoming important with recent trial results indicating the benefits of statins. We therefore aimed to determine the optimal time for lipid measurements after stroke. We hypothesized that TC would acutely decrease after stroke and return to baseline by 12 weeks. METHODS AND RESULTS: We performed a prospective, observational study of 50 patients (age 68.5 +/- 11.2 years) who presented with acute ischemic stroke. Of these, 22 (44%) were HMG-CoA reductase (statin) na?ve, 15 (30%) had already been on statins and 13 (26%) were commenced on statins. Of the 50 patients, 38 (76%) completed 12 weeks of follow-up, 5 died, and 7 were lost to follow-up. Fasting lipid profile (TC, low-density lipoprotein, high-density lipoprotein, triglyceride) was measured <48 h, 4 weeks and 12 weeks following ictus. In patients who were statin na?ve, there was a significant increase in TC at the week 12 evaluation. CONCLUSIONS: Cholesterol levels in acute stroke are an unreliable measure of lipid status. Initiation of statins should ideally be based on measurements taken 12 weeks after stroke. 相似文献
953.
Salvador R Peña A Menon DK Carpenter TA Pickard JD Bullmore ET 《Human brain mapping》2005,24(2):144-155
We analyzed the properties of the logarithm of the Rician distribution leading to a full characterization of the probability law of the errors in the linearized diffusion tensor model. An almost complete lack of bias, a simple relation between the variance and the signal-to-noise ratio in the original complex data, and a close approximation to normality facilitated estimation of the tensor components by an iterative weighted least squares algorithm. The theory of the linear model has also been used to derive the distribution of mean diffusivity, to develop an informative statistical test for relative lack of fit of the ellipsoidal (or spherical) model compared to an unrestricted linear model in which no specific shape is assumed for the diffusion process, and to estimate the signal-to-noise ratios in the original data. The false discovery rate (FDR) has been used to control thresholds for statistical significance in the context of multiple comparisons at voxel level. The methods are illustrated by application to three diffusion tensor imaging (DTI) datasets of clinical interest: a healthy volunteer, a patient with acute brain injury, and a patient with hydrocephalus. Interestingly, some salient features, such as a region normally comprising the basal ganglia and internal capsule, and areas of edema in patients with brain injury and hydrocephalus, had patterns of error largely independent from their mean diffusivities. These observations were made in brain regions with sufficiently large signal-to-noise ratios (>2) to justify the assumptions of the log Rician probability model. The combination of diffusivity and its error may provide added value in diagnostic DTI of acute pathologic expansion of the extracellular fluid compartment in brain parenchymal tissue. 相似文献
954.
955.
Clinically important outcomes in low back pain 总被引:8,自引:0,他引:8
Four important domains directly related to low back pain are: pain intensity, low-back-pain-specific disability, patient satisfaction with treatment outcome, and work disability. Within each of the domains, different questionnaires have been proposed. This chapter focuses on validated and widely used questionnaires. Details of the background and the measurement properties, and of the minimally clinically important change (MCIC) using these questionnaires, are described. The MCIC can be estimated using various methods and there is no consensus in the literature on what the most appropriate technique is. This chapter focuses primarily on two adequate and frequently used methods for estimating the MCIC. We argue that the MCIC should not be considered as a fixed value and that the MCIC values presented in this chapter are used as indications. For patients with subacute or chronic low back pain, the MCIC for pain on a visual analogue scale (VAS) should at least be 20mm and for acute low back pain it seems reasonable to suggest that the MCIC should at least be at the level of approximately 35mm. If a numerical rating scale (NRS) is used it seems reasonable to suggest that the MCIC should at least be 3.5 and 2.5 for patients with acute and chronic low back pain, respectively. For functional disability as measured with the Roland Disability Questionnaire it seems reasonable that the MCIC should at least be 3.5 points, whereas an MCIC of at least 10 points when the Oswestry Disability Index is used. For global perceived effect, we argue that the MCIC is most appropriately defined in terms of at least 'much improved' or 'very satisfied', instead of including 'slightly improved'. Finally, we argue that, from the point of view of cost effectiveness, every day of earlier return to work is important. The exact value for the MCIC can be determined, taking into account the aim of the measurement, the initial scores, the target population and the method used to assess MCIC. 相似文献
956.
957.
Clinical applications of 99mTc-sestamibi scintimammography 总被引:2,自引:0,他引:2
Taillefer R 《Seminars in nuclear medicine》2005,35(2):100-115
Mammography is the imaging modality of choice in detection of early, nonpalpable breast cancer. However, scintimammography may prove to be a very useful adjunct to a nondiagnostic or difficult mammography. Future prospective studies will have to be designed so that the specific clinical applications of scintimammography will be well defined. To be clinically relevant, each niche where scintimammography is potentially indicated should be clearly evaluated and incorporated into an algorithm of investigation of breast cancer, taking into consideration the relative advantages and limitations of scintimammography. Special care to obtain high-quality scintimammographic studies is mandatory. Because poor quality studies may be the major drawback, the nuclear medicine community should remind the lesson learned from radiologic mammography. Furthermore, it is also hoped that significant improvement in the scintigraphic equipment and data acquisition will be seen in a very near future to have more widespread clinical diagnostic applications of scintimammography. 相似文献
958.
Lea RG Hannah LT Redmer DA Aitken RP Milne JS Fowler PA Murray JF Wallace JM 《Pediatric research》2005,57(4):599-604
Most intrauterine growth restriction cases are associated with reduced placental growth. Overfeeding adolescent ewes undergoing singleton pregnancies restricts placental growth and reduces lamb birth weight. We used this sheep model of adolescent pregnancy to investigate whether placental growth restriction is associated with altered placental cell proliferation and/or apoptosis at d 81 of pregnancy, equivalent to the apex in placental growth. Adolescent ewes with singleton pregnancies were offered a high or moderate level of a complete diet designed to induce restricted or normal placental size at term, respectively. Bromodeoxyuridine (Brd-U) was administered to H and M ewes 1 h before slaughter. Placental tissues were examined for a) Brd-U (immunohistochemistry) and b) apoptosis regulatory genes by in situ hybridization, Northern analyses (bax, mcl-1), immunohistochemistry, and Western analyses (bax). Quantification was carried out by image analysis. Total placentome weights were equivalent between groups. Brd-U predominantly localized to the trophectoderm and was significantly lower in the H group. Bax and mcl-1 mRNA were localized to the maternal-fetal interface. Bax protein was significantly increased in the H group and predominant in the uninuclear fetal trophectoderm. These observations indicate that reduced placental size at term may be due to reduced placental cell proliferation and possibly increased apoptosis occurring much earlier in gestation. 相似文献
959.
960.
Duplications of the alimentary tract are rare anomalies that have been reported to occur all along the gastrointestinal tract. Of the various alimentary tract duplications, pyloric duplications are extremely rare. We report the case of a 3-day-old neonate who was antenatally diagnosed as having a cystic mass in the abdomen and who presented with vomiting on the 2nd day of life. At operation, a duplication cyst of the pylorus was removed successfully and a pyloroantrectomy performed. 相似文献