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91.
The aim of the present study was to evaluate the correlation amongst left ventricular (LV) functional parameters estimated by gated single photon emission tomography (GSPET) and two-dimensional (2D) M-mode, echocardiography (ECHOC). GSPET was performed in a single day stress/rest protocol by using either technetium-99m methoxy-isobutyl-isonitrile ((99m)Tc-MIBI) or technetium-99m tetrofosmin ((99m)Tc-myoview) in 36 consecutive patients, 21 males and 15 females; mean age 57.6+/-11.8 y, range 32-82 y. The various LV parameters studied were: ejection fraction (EF), end systolic volume (ESV), end diastolic volume (EDV), stroke volume (SV) and LV mass (LVM). The GSPET data were reconstructed using an automatic algorithm employing filtered back projection (FBP) and further analyzed by Emory cardiac (EC) toolbox versions EO-00369 and EO-00733 for the quantitative determinations of these parameters. All patients underwent ECHOC within 1-2 h of the post-stress data acquisition of GSPET. Our results showed that the LV volumes and the LVM showed good correlation (r=0.749 to 0.952, P=0.01). These values could thus be used interchangeably. The assessment of these parameters by GSPET therefore does not seem to be affected by the dose of the radioactivity administered as the dose of the (99m)Tc-labeled myocardial agents for acquiring rest study was approximately four times higher than that for the stress study. Our results also showed that the mean +/- SD values of the volumes and the EF of the LV evaluated by the two techniques, differed significantly except significant correlations for ESV, EDV and LVEF were observed between the two methods: r=0.574 to 0.954; 0.347 to 0.952 and 0.516 to 0.876 respectively. On the other hand, a wide disagreement was observed in estimating the LVM by the two techniques. The LVM measurements by 2D ECHOC were approximately double the values estimated by GSPET. Despite the large disagreement, a small correlation (r=0.33, P=0.05) was observed for LVM between the two techniques. In conclusion, although we observed a good correlation for LV volumes and LVM between the GSPET and the ECHOC techniques, yet these two techniques cannot be used interchangeably.  相似文献   
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The authors report a case of congenital clubfoot in a one-year-old male child, in which an accessory soleus muscle was noted intraoperatively, running anteromedially to the Achilles tendon and with a distinct insertion on the postero-medial aspect of the calcaneus. Correction of the varus and equinus of the hindfoot could only be achieved after cutting the tendon of the accessory soleus muscle at its insertion on the calcaneus.  相似文献   
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PURPOSE: To estimate gender- and age-specific prevalence of myopia and identify risk indicators for myopia in a population-based sample of Latino adults aged 40 years and older in La Puente, California. METHODS: Noncycloplegic automated refraction with supplemental standardized subjective refraction was performed for presenting visual acuity worse than 20/20. Potential risk indicators for myopia were evaluated by questionnaire and clinical examination. The gender- and age-specific prevalence of spherical equivalent myopia in phakic eyes was calculated. Multiple logistic regression identified independent risk indicators for myopia. RESULTS: Refractive error was analyzed for the worse eye of 5927 of 6357 participating Latinos. The overall prevalence of myopia < or = -1.0 D was 16.8%, and of high myopia < or = -5.0 D, 2.4%. When participants were stratified by age, myopia initially decreased with age and then increased in the oldest groups in association with nuclear opacification. Risk indicators for myopia were: oldest and youngest age groups, presence of diabetes mellitus, high acculturation, high school or higher education, and birth in the United States. The latter two were also predictors of high myopia. CONCLUSIONS: Risk indicators for myopia in adult Latinos include higher education, birth in the United States, high acculturation, and diabetes. The burden of myopia in older Latinos exceeds that in African Americans and non-Hispanic whites in the United States.  相似文献   
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Management of complete external third nerve palsy is a challenge to a strabismologist; as four of six extra-ocular muscles are affected, it leaves eye in fixed hypotropic and exotropic position (Srivastava et al., 2004). Although numerous surgical procedures have been described, none has been found to be ideal for all cases. Horizontal supramaximal recession-resection procedure may work in cases having some function of medial rectus (Harley, 1980). In cases of complete external palsy, anchoring of globe to periosteum of medial orbital wall using different structures has been described (Villasenor Solares et al., 2000; Bicas, 1991; Salazar-Leon et al., 1998), as recession-resection may result in large residual deviation and/or eye drifts back to abducted position due to unopposed lateral rectus action (Von Noorder, 1996). These anchoring procedures are with associated problems of skin incision, thigh surgery or loss of superior oblique function (Villasenor Solares et al., 2000; Bicas, 1991; Salazar-Leon et al., 1998). We describe a new and safe technique for management of complete external third nerve palsy by anchoring insertion of medial rectus to medial wall periosteum, posterior to posterior lacrimal crest, along with supra maximal recession of lateral rectus.  相似文献   
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N-(4-hydroxyphenyl)retinamide (4-HPR), a synthetic retinoid is under clinical evaluation as a therapeutic agent in a variety of cancers. Its mechanism(s) of action involves multiple overlapping pathways that still remain unclear. In glioma cells its mechanism of action is not well elucidated. Here, we show that 4-HPR and not all-trans retinoic acid and 9-cis retinoic acid effectively induce apoptosis in glioma cells. 4-HPR-induced apoptosis is associated with hydroperoxide production and loss of mitochondrial membrane potential (Delta Psi(m)). Ultrastructural changes further indicate 4-HPR-induced mitochondrial swelling, endoplasmic reticulum (ER) dilation as well as close proximity of mitochondria and ER. As suggested by dilated ER, 4-HPR treatment increased the free cytosolic Ca(2+) as well as mitochondrial Ca(2+). Chelation of extracellular Ca(2+) by EGTA did not prevent Ca(2+) elevation, thus suggesting involvement of intracellular calcium stores in the release. Buffering of intracellular calcium by BAPTA-AM did not prevent 4-HPR-induced apoptosis; however, blocking the release of Ca(2+) from ER by heparin inhibited apoptosis, indicating the role of depletion of Ca(2+) from ER stores in apoptosis. 4-HPR treatment also resulted in an increase in Bax levels along with its translocation to mitochondria that promote mitochondrial membrane permeabilization. 4-HPR-induced apoptosis was further associated with the release of cytochrome c and apoptosis-inducing factor (AIF) from mitochondria to cytosol and nucleus, respectively, along with caspase-3 and caspase-7 activation. However, AIF nuclear translocation, peripheral chromatin condensation and apoptosis were not completely prevented by general caspase inhibitors, thus suggesting involvement of a caspase-dependent and caspase-independent pathway in 4-HPR-induced apoptosis. Taken together, these results suggest the role of mitochondrial-mediated pathway and ER stress as a key event in 4-HPR-induced apoptosis in glioma cells.  相似文献   
100.
Experiments were conducted with a cationic lipid-formulated pDNA vaccine (VCL-AB01) to evaluate the models used to determine biodistribution, persistence and the potential for integration (into genomic DNA) of plasmid DNA-based vaccines. Mice were injected with a high-dose volume of 50 microL unilaterally containing approximately 1.33 x 10(13) plasmid copy numbers (PCN) or a low-dose volume of 20 microL bilaterally ( approximately 5.3 x 10(12) PCN). Rabbits were injected bilaterally with a 0.5 mL ( approximately 1.33 x 10(14) PCN) volume. Injection site muscle tissue was harvested two days, one month, and two months postinjection for the low-dose murine and rabbit models and two days and two months postinjection for the high-dose murine model. Total DNA was extracted and analyzed by real-time quantitative PCR for sequences specific to the injected pDNA. The geometric mean PCN/microg of total DNA from the high and low dose models were compared to determine if injection volume impacts clearance and/or persistence. Results from these studies showed that PCN clearance over two months was similar in mice injected with 20 microL and rabbits injected with 0.5 mL, but PCN clearance was slower in mice injected with similar PCN in 50 microL (1.33 x 10(13) PCN) compared to 20 microL (5.3 x 10(12) PCN). Persistence at two months in the rabbit and low-dose murine models was comparable, with geometric mean of 5.22 x 10(3) PCN/microg of total DNA for the low-dose volume murine model and 2.81 x 10(3)/microg DNA for the rabbit model. Interanimal variability in persistence was not impacted by dose volume.  相似文献   
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