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121.
The nasolacrimal duct in association with the lacrimal puncta, lacrimal canaliculi and lacrimal sac functions to collect and drain the tear film into the nasal cavity at the inferior nasal meatus where a fold of nasal mucosa, the so-called valve of Hasner, prevents mucous from entering the nose. High-resolution computed tomography demonstrated air inside the sac and nasolacrimal duct in approximately 29.3% of healthy patients suggesting that the system is not completely competent and that air and secretions might reach the precorneal film. 相似文献
122.
Soraia C. Abreu Mariana A. Antunes Júlia C. de Castro Milena V. de Oliveira Elga Bandeira Debora S. Ornellas Bruno L. Diaz Marcelo M. Morales Débora G. Xisto Patricia R.M. Rocco 《Respiratory physiology & neurobiology》2013,187(2):190-198
We compared the effects of bone marrow-derived mononuclear cells (BMMCs) and mesenchymal stromal cells (MSCs) on airway inflammation and remodeling and lung mechanics in experimental allergic asthma. C57BL/6 mice were sensitized and challenged with ovalbumin (OVA group). A control group received saline using the same protocol. Twenty-four hours after the last challenge, groups were further randomized into subgroups to receive saline, BMMCs (2 × 106) or MSCs (1 × 105) intratracheally. BMMC and MSC administration decreased cell infiltration, bronchoconstriction index, alveolar collapse, collagen fiber content in the alveolar septa, and interleukin (IL)-4, IL-13, transforming growth factor (TGF)-β and vascular endothelial growth factor (VEGF) levels compared to OVA-SAL. Lung function, alveolar collapse, collagen fiber deposition in alveolar septa, and levels of TGF-β and VEGF improved more after BMMC than MSC therapy. In conclusion, intratracheal BMMC and MSC administration effectively modulated inflammation and fibrogenesis in an experimental model of asthma, but BMMCs was associated with greater benefit in terms of reducing levels of fibrogenesis-related growth factors. 相似文献
123.
Caruso RA Cicciarello R Gagliardi ME Albiero F Costa G Fedele F Cavaliere R Finocchiaro G Mesiti M Cavallari V 《Ultrastructural pathology》2008,32(4):153-159
A primary invasive micropapillary carcinoma of the breast in a 46-year-old woman is reported. Histologically, it was composed predominantly of papillary tumor cell clusters without fibrovascular cores, surrounded by a clear space. Tumor cells were positive for cytokeratin (CK) 7, estrogen receptor (ER), and progesterone receptor (PR), but negative for p53, CK 20, CD34, c-Erb-B2, CK5, epidermal growth factor receptor (EGFR), vimentin, and c-kit. MUC1 expression was found at the reversed apical membrane of neoplastic cell clusters. Accordingly, electron microscopy showed the lack of basement membrane and presence of microvilli at the basal surface of the tumor cells. Moreover, ultrastructural examination revealed single tumor cell death characterized by patchy condensations of chromatin throughout the nucleus. These nuclear alterations were associated with the occurrence of empty cytoplasmic vacuoles, conferring a necrosis-like phenotype to this cell death. Alternative programmed cell deaths are reviewed and their morphologic distinction is discussed. 相似文献
124.
125.
The role of protein kinase C (PKC) in the steroidogenic action of angiotensin II (AII) was investigated by depletion of endogenous PKC using prolonged incubation with phorbol ester and direct measurement of PKC in isolated rat adrenal glomerulosa cells. PKC activity was measured by incorporation of 32P from [gamma 32P]ATP into histone in the presence of cytosolic and detergent-solubilized membrane fractions purified by diethylaminoethyl cellulose chromatography. Basal PKC activity was higher in cytosol than in membranes (1,000 +/- 57 and 413 +/- 14 pmol P incorporated/mg.min, respectively). After incubation of the cells with AII for 5, 15, 30, and 60 min, PKC activity in the cytosol decreased by 5, 18, 25, and 27%, respectively, while in the membrane there was a transient increase of 15% at 15 min returning to basal by 60 min. Incubation of the cells with 100 nM 12-O-tetradecanoylphorbol-13-acetate (TPA) resulted in transient translocation of PKC activity to the membrane (15 min) which was followed by a 64% decrease in total cellular enzyme activity after 3 h. In PKC-depleted cells, the aldosterone response to ACTH was increased by 25% but AII-stimulated steroidogenesis was unchanged. In contrast, in cells in which PKC was translocated to the membrane by a 15 min preincubation with TPA, aldosterone response to AII was enhanced by 40%, while the response to ACTH was reduced by 30%; under these conditions membrane PKC levels rapidly returned to basal. However, the changes in aldosterone response were still evident when addition of AII or ACTH was delayed for up to 30 min after removal of TPA, indicating a persistent modification in the cell membrane secondary to PKC activation. Aldosterone responses to potassium were not altered by preincubation of the cells with TPA. The inactive phorbol ester analog, 4 alpha-hydroxyphorbol-12,13-dibutyrate, had no effect on the steroid responses to either stimulus. The small but significant translocation of PKC activity from cytosol to membrane after treatment of rat adrenal glomerulosa cells with AII suggests that AII activates PKC. However, the fact that aldosterone responses to AII are potentiated during TPA-induced PKC translocation to the membrane suggests that AII and phorbol esters do not share the same mechanism of action in the regulation of steroidogenesis.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
126.
Leonardo Osti Rocco Papalia Angelo Del Buono Francesco Leonardi Vincenzo Denaro Nicola Maffulli 《Knee surgery, sports traumatology, arthroscopy》2011,19(3):412-417
Purpose
To compare the outcomes of arthroscopic ACL reconstruction procedure in 20 middle-aged patients (12 men and 8 women) and 20 subjects younger than 30 years (control group) at a minimum post-operative follow-up of 24 months. 相似文献127.
Papalia R Franceschi F Del Buono A Zampogna B Maffulli N Denaro V 《Sports medicine and arthroscopy review》2011,19(4):342-347
In the operative management of rotator cuff disease, comparable functional results have been reported after open or mini-open repair and arthroscopic fixation. Surgical repair aims to re-establish an anatomical configuration of the tendon-bone construct for restoring its mechanical performance. Single row repair is the most commonly used technique, but recently some authors have proposed to re-establish the rotator cuff footprint with 2 rows of suture anchors ("double row" repair). In regard to imaging assessment, at time zero double row repair results being more anatomic and allows for structurally sound restoration of the rotator cuff footprint. However, this does not seem to translate into superior clinical outcomes for the double row repair when evaluating all different sizes of rotator cuff tears as a whole. The scientific basis for recommending single or double row repair as preferred treatment for patients with rotator cuff tear is questionable, as minimal differences have been measured on clinical and functional rating scales. 相似文献
128.
Recently, some studies have demonstrated the effectiveness of two latent variable approaches in which hand preferences are analysed using either latent class methods or latent class factor (LCF) methods. The main aims of this study are: (i) to establish whether these approaches are adequate for assessing footedness, (ii) to evaluate their appropriateness when hand and foot preferences are jointly analysed, and (iii) to measure the association between handedness and footedness based on the examined latent variable models. To this end, a dataset providing information about the limb used to perform ten hand actions and three foot movements by 2236 young Italian sportspeople is analysed. The first aim is pursued through an exploratory analysis of the observed foot preferences; according to this analysis, footedness patterns are adequately described by two latent levels of footedness. As far as the second aim is concerned, a confirmatory analysis of foot and hand preferences is carried out; the best fit to the dataset is obtained using a two-dimensional LCF model with four latent levels of handedness and two latent levels of footedness. Finally, the association between handedness and footedness resulting from the employed methods is remarkably lower than that registered in other studies. 相似文献
129.
Caitlin Stafford Todd D. Francone Peter W. Marcello Patricia L. Roberts Rocco Ricciardi 《Journal of gastrointestinal surgery》2018,22(3):503-507
Background
Treatment of left-sided colorectal anastomotic leaks often requires fecal stream diversion for prevention of further septic complications. To manage anastomotic leak, it is unclear if diverting ileostomy provides similar outcomes to Hartmann resection with colostomy.Methods
We identified all patients who developed anastomotic leak following left-sided colorectal resections from 1/2012 through 12/2014 using the American College of Surgeons National Surgical Quality Improvement Program. Then, we examined the risk of mortality and abdominal reoperation in patients treated with diverting ileostomy as compared to Hartmann resection.Results
There were 1745 patients who experienced an anastomotic leak in a cohort of 63,748 patients (3.7%). Two hundred thirty-five patients had a reoperation for anastomotic leak involving the formation of a diverting ileostomy (n = 77) or Hartmann resection (n = 158). There was no difference in mortality or abdominal reoperation in patients treated with diverting ileostomy (3.9, 7.8%) versus Hartmann resection (3.8, 6.3%) (p = 0.8).Conclusion
There was no difference in the outcomes of mortality or need for second abdominal reoperation in patients treated with diverting ileostomy as compared to Hartmann resection for left-sided colorectal anastomotic leak. Thus, select patients with left-sided colorectal anastomotic leaks may be safely managed with diverting ileostomy.130.
Chieh JJ Brevetti LS Scholz PM Graham AM Ciocca RG 《Journal of vascular surgery》2003,37(5):1094-1097
Takayasu aortitis (TA) is a chronic inflammatory disease predominantly seen in young Asian women. The disease is idiopathic and largely affects the aorta and its major branches. The basic pathologic changes in TA are fibrosis and subsequent occlusion of the large arteries. TA is classically termed "pulseless" disease, with manifestations during the occlusive stage including limb ischemia, renovascular hypertension, and heart failure. Arterial dilation and aneurysm are largely unappreciated manifestations of TA, but they occur in as many as 32% of affected patients. We report chronic "burned out" TA in a 23-year-old Hispanic woman with isolated aneurysms of the descending thoracic aorta, abdominal aorta, and common iliac arteries, without occlusive disease. 相似文献