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81.
S.-H. Lhee Y.H. Jo B.Y. Kim B.M. Nam J.G. Nemeno S. Lee W. Yang J.I. Lee 《Transplantation proceedings》2013
Mesenchymal stem cells (MSCs) are multipotent stromal elements that can differentiate into a variety of cell types. MSCs are good sources of therapeutic cells for degenerative diseases. For these reason, many researchers have focused on searching for other sources of MSCs. To obtain MSCs for clinical use requires surgery of the donor that therefore can induce donor morbidity, since the common sources at present are bone marrow and adipose tissues. In this study, we investigated the existence of MSCs in postoperative discarded tissues. Subacromial bursal tissues were obtained from the shoulders of 3 injured patients. The cells from the bursa tissues were isolated through treatment with collagenase. The isolated cells were then seeded and expanded by serial passaging under normal culture system. To evaluate MSC characteristics of the cells, their MSC markers were confirmed by mRNA and protein expression. Multipotent ability was assessed using differentiation media and immunohistochemistry. Cells from the bursa expressed MSCs markers—CD29, CD73, CD90, and PDGFRB (platelet-derived growth factor receptor-beta). Moreover, as to their multipotency, bursal cells differentiated into adipocytes (fat cells), osteocytes (bone cells), and chondrocytes (cartilage cells). In summary, we showed that MSCs could be generated from the subacromial bursa, which is medical waste after surgery. 相似文献
82.
83.
Air-trapping zone surrounding sclerosing hemangioma of the lung 总被引:17,自引:0,他引:17
Nam JE Ryu YH Cho SH Lee YJ Kim HJ Lee DY Choe KO Kim SJ 《Journal of computer assisted tomography》2002,26(3):358-361
We present two cases of sclerosing hemangioma of the lung with a peculiar radiologic finding: an air-trapping zone surrounding the tumor. On microscopic examinations, the tumor was of the hemangiomatous subtype, and the radiolucent zone corresponded to enlarged alveoli with septal destruction. A possible mechanism in the production of an air-trapping zone around a sclerosing hemangioma is bleeding from the highly vascular tumor followed by expectoration in communication with an airway. We reviewed the literature on the air meniscus sign in sclerosing hemangioma and concluded that although it is not a common finding, it could be of help in the confident diagnosis of sclerosing hemangioma and in differentiating it from other benign tumors of the lung. 相似文献
84.
We investigated the therapeutic effect of topical Risedronate (RIS) on a mouse model of estrogen-deficient osteoporosis. Fourteen-week-old female mice were ovariectomized and assigned to 4 groups: SHAM-operated (SHAM), OVX mice treated with vehicle (OVX-V), OVX mice treated with 0.2% RIS (OVX-0.2% RIS), and OVX-mice treated with 0.02% RIS (OVX-0.02% RIS). Topical samples containing RIS were prepared in 10% (w/w) polyethylene glycol (PEG, MW 400) and 80 μg of sample was spread on the mice's mid-backs every 3 days for 5 weeks. Micro-CT analysis of femora demonstrated that OVX-0.2% RIS exhibited a 29% greater bone mineral density and 24% greater bone volume fraction than that of OVX-V group. Investigation of the trabecular bone in OVX-0.2% RIS revealed a 24% higher bone volume (BV/TV), 51% higher trabecular number (Tb.N), and 40% lower trabecular separation (Tb.Sp) compared to OVX-V mice. Additionally, bone phenotypes of tibiae were further confirmed by histological analysis. OVX-0.2% RIS group exhibited a 494% greater BV/TV, 464% less Tb.Sp, 81% greater active osteoclast surface (Oc.S/BS) and 26% less osteoclast number (N.Oc/BS) than that of OVX-V group. Collectively, these results indicated that topical delivery of RIS has powerful pharmaceutical effects on the prevention of osteoporosis and bone turnover. 相似文献
85.
Jung Min Hong Hae Kyu Kim Eun Soo Kim Hee Young Kim Nam Won Kim Ji Young Yoon 《Journal of anesthesia》2012,26(6):910-913
We report a case of a patient with a double-primary aortoenteric fistula with an abdominal aortic aneurysm. A 75-year-old man was taken to the operating room for the repair of an abdominal aortic aneurysm and a suspected aortoenteric fistula between the aorta and sigmoid colon. Sudden onset of massive bleeding through the nasogastric tube occurred after the induction of anesthesia. Surgical exploration confirmed an unexpected aortoduodenal fistula. Primary aortoenteric fistula is extremely rare and difficult to diagnose, and may cause fatal bleeding. The possibility of the presence of aortoenteric fistula, including multiple types, should be considered in the anesthetic management of abdominal aortic aneurysm. 相似文献
86.
Background
Lymph node metastases occur frequently in patients with papillary thyroid carcinoma (PTC), and the central compartment of the neck is the most frequently involved site. Some authors advocate prophylactic central neck dissection (CND) during total thyroidectomy. However, little is known about the effects of prophylactic unilateral CND in papillary thyroid microcarcinoma (PTMC) patients who undergo hemithyroidectomy. This study was designed to investigate the impact of prophylactic unilateral CND in this population. 相似文献87.
SW Park TN Kim JH Yoon TH Kim JM Chung UB Jeon W Lee 《International urology and nephrology》2012,44(5):1397-1402
Objectives
To establish the undisputed the value of washout rate for adrenal adenoma using delayed enhanced CT, we evaluated diagnostic performance of cut-off value and delayed time of washout rate by final pathologic diagnosis in a multicenter study.Methods
We reviewed the pathologic and clinical records of 244 patients underwent adrenalectomies at 5 university hospitals between 2005 and 2009. We calculated the mean Housfield units (HU) of adrenal lesion at non-enhancing CT, and early and delayed enhanced CT using the region of interest. We used ROC curves to determine the specificity and sensitivity of non-enhanced CT scans and the washout rate according to the various cut-off for adrenal adenomas.Results
We divided the patients into adrenal adenoma group (n?=?138) and non-adrenal adenoma group (n?=?106) based on final pathologic report. Using the unenhanced images with a threshold of 10 HU, the sensitivity was 45.7?%, and the specificity was 97.1?%. Using the 15-min-washout rate with a threshold of 55?%, the sensitivity was 93.9?%, and the specificity was 95.8?%.Conclusions
Regardless of various CT machines and protocols, a washout rate of 15-min-delayed CT was most useful in the diagnosis of adrenal adenomas due to the early inflow and outflow of contrast media in the tissues of adrenal adenomas. 相似文献88.
Nam TW Yoo CI Kim HT Kwon CH Park JY Kim YK 《Journal of bone and mineral metabolism》2008,26(6):551-560
The present study was undertaken to evaluate effects of quercetin, a major dietary flavonoid occurring in foods of plant origin,
on cell viability and migration of osteoblastic cells. Quercetin inhibited cell viability, which was largely attributed to
apoptosis, in a dose-and time-dependent manner in osteoblastic cells. Similar cytotoxicity of quercetin was observed in adipose
tissue-derived stromal cells. Quercetin exerted a protective effect against H2O2-induced cell death, whereas it increased TNF-α-induced cell death. Western blot analysis showed that quercetin induced activation
of ERK and p38, but not JNK. Quercetin-induced cell death was prevented by the ERK inhibitor PD98059, but not by inhibitors
of p38 and JNK. Quercetin increased Bax expression and caused depolarization of mitochondrial membrane potential, which were
inhibited by PD98059. Quercetin induced caspase-3 activation, and the quercetininduced cell death was prevented by caspase
inhibitors. Quercetin inhibited cell migration, and its effect was prevented by inhibitors of ERK and p38. Taken together,
these findings suggest that quercetin induces apoptosis through a mitochondria-dependent mechanism involving ERK activation
and inhibits migration through activation of ERK and p38 pathways. Quercetin may exert both protective and deleterious effects
in bone repair. 相似文献
89.
Prevalence of osteoporosis and reference data for lumbar spine and hip bone mineral density in a Korean population 总被引:1,自引:0,他引:1
Cui LH Choi JS Shin MH Kweon SS Park KS Lee YH Nam HS Jeong SK Im JS 《Journal of bone and mineral metabolism》2008,26(6):609-617
The aims of this study were to establish reference data for bone mineral density (BMD) at central skeletal sites using Lunar
dual-energy X-ray absorptiometry (DXA), and to estimate the age-and sex-specific prevalence of osteoporosis in a Korean population.
We performed a population-based, cross-sectional study. The subjects were 4148 (1810 men and 2338 women) Korean adults, aged
20–79 years. The BMD for central sites (lumbar spine, femoral neck, trochanter, and Ward’s triangle) were measured by DXA.
The standardized prevalence of osteoporosis among individual aged 50–79 years in lumbar spine, femoral neck, Ward’s triangle,
and trochanter was 40.1%, 12.4%, 28.4%, and 4.4% in women and 6.5%, 5.9%, 3.7%, and 1.6% in men, respectively. In women, peak
BMD occurred in the age range 40–49 years for the femoral neck and trochanter, 30–39 years for the lumbar spine, and 20–29
years for Ward’s triangle. In men, peak BMD values were observed at 20–29 years for all measured sites. This study establishes
a normative database for BMD at central skeletal sites using dualenergy X-ray absorptiometry and provides more reliable information
on the prevalence of osteoporosis in Korea. 相似文献
90.
Patricia A. Gonzales Trairak Pisitkun Jason D. Hoffert Dmitry Tchapyjnikov Robert A. Star Robert Kleta Nam Sun Wang Mark A. Knepper 《Journal of the American Society of Nephrology : JASN》2009,20(2):363-379
Normal human urine contains large numbers of exosomes, which are 40- to 100-nm vesicles that originate as the internal vesicles in multivesicular bodies from every renal epithelial cell type facing the urinary space. Here, we used LC-MS/MS to profile the proteome of human urinary exosomes. Overall, the analysis identified 1132 proteins unambiguously, including 177 that are represented on the Online Mendelian Inheritance in Man database of disease-related genes, suggesting that exosome analysis is a potential approach to discover urinary biomarkers. We extended the proteomic analysis to phosphoproteomic profiling using neutral loss scanning, and this yielded multiple novel phosphorylation sites, including serine-811 in the thiazide-sensitive Na-Cl co-transporter, NCC. To demonstrate the potential use of exosome analysis to identify a genetic renal disease, we carried out immunoblotting of exosomes from urine samples of patients with a clinical diagnosis of Bartter syndrome type I, showing an absence of the sodium-potassium-chloride co-transporter 2, NKCC2. The proteomic data are publicly accessible at http://dir.nhlbi.nih.gov/papers/lkem/exosome/.Urinary exosomes are small extracellular vesicles (<100 nm in diameter) that originate from the internal vesicles of multivesicular bodies (MVB) in renal epithelial cells, including glomerular podocytes, renal tubule cells, and the cells lining the urinary drainage system.1 Exosomes are released into the urine when the outer membrane of the MVB fuses with the apical plasma membrane of the epithelial cell.Exosomes can be recovered from the urine by differential centrifugation as a low-density membrane fraction. Exosome isolation can result in marked enrichment of low-abundance urinary proteins that have potential pathophysiologic significance. As a consequence, we and others have been working to define optimal conditions for their isolation and purification as a prelude to their use in biomarker discovery studies.1–3In this study, we thoroughly expanded the known proteome of human urinary exosomes by using a highly sensitive LC-MS/MS system, improved software for identification of peptide ions and a more elaborate data analysis strategy than in our previous study. In addition, we used a neutral loss scanning approach4 to investigate the phosphoproteome of human urinary exosomes. The study identified 1412 proteins including 14 phosphoproteins in human urinary exosomes. Overall, there are 177 proteins that are associated with diseases as judged by their presence on the Online Mendelian Inheritance in Man (OMIM) database, 34 of which are known to be associated with renal diseases. The potential clinical usefulness of urinary exosomes was demonstrated using the well-defined renal tubulopathy, Bartter syndrome type I, as an example. The rich information from the proteomic analysis also provides further insight into the biogenesis of urinary exosomes. 相似文献