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51.
H A Carrasco L Guerrero H Parada C Molina E Vegas R Chuecos 《International journal of cardiology》1990,28(1):35-41
To study the relationship of complex ventricular arrhythmias to the presence and extent of myocardial damage, 556 chronic chagasic patients were submitted to an extensive protocol, including left ventricular cineangiography and Holter monitoring, and properly classified according to clinical, electrocardiographic and hemodynamic findings. Stages of the clinical-hemodynamic classification corresponded to increasing degrees of myocardial damage, age, prevalence and complexity of ventricular arrhythmias. Myocardial damage (particularly left ventricular dilatation) was the most important clinical factor linked to the presence of complex ventricular arrhythmias. A clear difference in terms of ventricular function was found only when arrhythmias were grouped into simple (Lown grades I and II) and complex (grades III and IV) forms. It is recommended that any classification for chagasic patients must be based on signs of myocardial involvement, instead of clinical or electrocardiographic findings alone. Evaluation should include accurate determination of left ventricular myocardial function, along with the search for the presence of complex ventricular arrhythmias and abnormalities of conduction. 相似文献
52.
Funez MI Ferrari LF Duarte DB Sachs D Cunha FQ Lorenzetti BB Parada CA Ferreira SH 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(49):19038-19043
Previous work from our group showed that intrathecal (i.t.) administration of substances such as glutamate, NMDA, or PGE2 induced sensitization of the primary nociceptive neuron (PNN hypernociception) that was inhibited by a distal intraplantar (i.pl.) injection of either morphine or dipyrone. This pharmacodynamic phenomenon is referred to in the present work as “teleantagonism”. We previously observed that the antinociceptive effect of i.t. morphine could be blocked by injecting inhibitors of the NO signaling pathway in the paw (i.pl.), and this effect was used to explain the mechanism of opioid-induced peripheral analgesia by i.t. administration. The objective of the present investigation was to determine whether this teleantagonism phenomenon was specific to this biochemical pathway (NO) or was a general property of the PNNs. Teleantagonism was investigated by administering test substances to the two ends of the PNN (i.e., to distal and proximal terminals; i.pl. plus i.t. or i.t. plus i.pl. injections). We found teleantagonism when: (i) inhibitors of the NO signaling pathway were injected distally during the antinociception induced by opioid agonists; (ii) a nonselective COX inhibitor was tested against PNN sensitization by IL-1β; (iii) selective opioid-receptor antagonists tested against antinociception induced by corresponding selective agonists. Although the dorsal root ganglion seems to be an important site for drug interactions, the teleantagonism phenomenon suggests that, in PNNs, a local sensitization spreads to the entire cell and constitutes an intriguing and not yet completely understood pharmacodynamic property of this group of neurons. 相似文献
53.
54.
Laparoendoscopic single‐site (LESS) vs laparoscopic living‐donor nephrectomy: a systematic review and meta‐analysis
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Riccardo Autorino Luis Felipe Brandao Bashir Sankari Homayoun Zargar Humberto Laydner Oktay Akça Marco De Sio Vincenzo Mirone Shih‐Chieh J. Chueh Jihad H. Kaouk 《BJU international》2015,115(2):206-215
The aim of this study was to provide a systematic review and meta‐analysis of reports comparing laparoendoscopic single‐site (LESS) living‐donor nephrectomy (LDN) vs standard laparoscopic LDN (LLDN). A systematic review of the literature was performed in September 2013 using PubMed, Scopus, Ovid and The Cochrane library databases. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta‐analyses criteria. Weighted mean differences (WMDs) were used to measure continuous variables and odds ratios (ORs) to measure categorical ones. Nine publications meeting eligibility criteria were identified, including 461 LESS LDN and 1006 LLDN cases. There were more left‐side cases in the LESS LDN group (96.5% vs 88.6%, P < 0.001). Meta‐analysis of extractable data showed that LLDN had a shorter operative time (WMD 15.06 min, 95% confidence interval [CI] 4.9–25.1; P = 0.003), without a significant difference in warm ischaemia time (WMD 0.41 min, 95% CI –0.02 to 0.84; P = 0.06). Estimated blood loss was lower for LESS LDN (WMD ?22.09 mL, 95% CI –29.5 to –14.6; P < 0.001); however, this difference was not clinically significant. There was a greater likelihood of conversion for LESS LDN (OR 13.21, 95% CI 4.65–37.53; P < 0.001). Hospital stay was similar (WMD –0.11 days, 95% CI –0.33 to 0.12; P = 0.35), as well as the visual analogue pain score at discharge (WMD –0.31, 95% CI –0.96 to 0.35; P = 0.36), but the analgesic requirement was lower for LESS LDN (WMD –2.58 mg, 95% CI –5.01 to –0.15; P = 0.04). Moreover, there was no difference in the postoperative complication rate (OR 1.00, 95% CI 0.65–1.54; P = 0.99). Renal function of the recipient, as based on creatinine levels at 1 month, showed similar outcomes between groups (WMD 0.10 mg/dL, –0.09 to 0.29; P = 0.29). In conclusion, LESS LDN represents an emerging option for living kidney donation. This procedure offers comparable surgical and early functional outcomes to the conventional LLDN, with a lower analgesic requirement. However, it is more technically challenging than LLDN, as shown by a greater likelihood of conversion. The role of LESS LDN remains to be defined. 相似文献
55.
Elen de Souza TOLENTINO Cleverson Soares TEIXEIRA Luciana Reis AZEVEDO-ALANIS Heitor Marques HONóRIO José Humberto DAMANTE 《Journal of applied oral science : revista FOB》2015,23(3):255-264
There are several age-related microscopic changes in the salivary glands, including the increase in the number of duct-like structures (DLS). However, the true origin and the phenotype of the DLS are not known.
Objective
To evaluate the phenotype and the cell proliferation index of the DLS of human sublingual glands.Material and Methods
Sixty sublingual glands obtained from human cadavers were divided into two groups - 0-30 and 61-90 years old. The phenotype was estimated by immunostaining for cytokeratin 19 (CK 19) and the S-100 protein as well as by the presence of mucin and glycogen. The cell proliferation index was determined by the Ki-67 antibody. The histochemical techniques used periodic acid-Schiff (PAS) and Alcian Blue. In each captured microscopic field, the DLS were counted to establish a percentage for the staining profile. The statistical analysis was accomplished using Student’s t-test, the Mann-Whitney test and Pearson’s correlation coefficient (p<0.05).Results
Comparing both groups, only CK 19 showed a statistically significant difference (p=0.033), with the strongest expression in the elderly group. There was no significant difference between PAS and Alcian Blue (p=0.270). In both groups, the immunostaining for CK 19 was stronger than that for S-100 (p=0.004;p<0.001), but there was no correlation between the two immunomarkers (ρ=-0.163; p=0.315). There was no immunostaining for Ki-67.Conclusions
DLS demonstrate a ductal phenotypic profile and do not present cell proliferation activity. DLS may represent a regressive process arising from acini or represent the result of metaplasia. 相似文献56.
Recent developments in neurofibromatoses and RASopathies: Management,diagnosis and current and future therapeutic avenues
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Katherine A. Rauen Susan M. Huson Emma Burkitt‐Wright D. Gareth Evans Said Farschtschi Rosalie E. Ferner David H. Gutmann C. Oliver Hanemann Bronwyn Kerr Eric Legius Luis F. Parada Michael Patton Juha Peltonen Nancy Ratner Vincent M. Riccardi Thijs van der Vaart Miikka Vikkula David H. Viskochil Martin Zenker Meena Upadhyaya 《American journal of medical genetics. Part A》2015,167(1):1-10
57.
Willingham SB Volkmer JP Gentles AJ Sahoo D Dalerba P Mitra SS Wang J Contreras-Trujillo H Martin R Cohen JD Lovelace P Scheeren FA Chao MP Weiskopf K Tang C Volkmer AK Naik TJ Storm TA Mosley AR Edris B Schmid SM Sun CK Chua MS Murillo O Rajendran P Cha AC Chin RK Kim D Adorno M Raveh T Tseng D Jaiswal S Enger PØ Steinberg GK Li G So SK Majeti R Harsh GR van de Rijn M Teng NN Sunwoo JB Alizadeh AA Clarke MF Weissman IL 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(17):6662-6667
CD47, a "don't eat me" signal for phagocytic cells, is expressed on the surface of all human solid tumor cells. Analysis of patient tumor and matched adjacent normal (nontumor) tissue revealed that CD47 is overexpressed on cancer cells. CD47 mRNA expression levels correlated with a decreased probability of survival for multiple types of cancer. CD47 is a ligand for SIRPα, a protein expressed on macrophages and dendritic cells. In vitro, blockade of CD47 signaling using targeted monoclonal antibodies enabled macrophage phagocytosis of tumor cells that were otherwise protected. Administration of anti-CD47 antibodies inhibited tumor growth in orthotopic immunodeficient mouse xenotransplantation models established with patient tumor cells and increased the survival of the mice over time. Anti-CD47 antibody therapy initiated on larger tumors inhibited tumor growth and prevented or treated metastasis, but initiation of the therapy on smaller tumors was potentially curative. The safety and efficacy of targeting CD47 was further tested and validated in immune competent hosts using an orthotopic mouse breast cancer model. These results suggest all human solid tumor cells require CD47 expression to suppress phagocytic innate immune surveillance and elimination. These data, taken together with similar findings with other human neoplasms, show that CD47 is a commonly expressed molecule on all cancers, its function to block phagocytosis is known, and blockade of its function leads to tumor cell phagocytosis and elimination. CD47 is therefore a validated target for cancer therapies. 相似文献
58.
Volkmer JP Sahoo D Chin RK Ho PL Tang C Kurtova AV Willingham SB Pazhanisamy SK Contreras-Trujillo H Storm TA Lotan Y Beck AH Chung BI Alizadeh AA Godoy G Lerner SP van de Rijn M Shortliffe LD Weissman IL Chan KS 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(6):2078-2083
Current clinical judgment in bladder cancer (BC) relies primarily on pathological stage and grade. We investigated whether a molecular classification of tumor cell differentiation, based on a developmental biology approach, can provide additional prognostic information. Exploiting large preexisting gene-expression databases, we developed a biologically supervised computational model to predict markers that correspond with BC differentiation. To provide mechanistic insight, we assessed relative tumorigenicity and differentiation potential via xenotransplantation. We then correlated the prognostic utility of the identified markers to outcomes within gene expression and formalin-fixed paraffin-embedded (FFPE) tissue datasets. Our data indicate that BC can be subclassified into three subtypes, on the basis of their differentiation states: basal, intermediate, and differentiated, where only the most primitive tumor cell subpopulation within each subtype is capable of generating xenograft tumors and recapitulating downstream populations. We found that keratin 14 (KRT14) marks the most primitive differentiation state that precedes KRT5 and KRT20 expression. Furthermore, KRT14 expression is consistently associated with worse prognosis in both univariate and multivariate analyses. We identify here three distinct BC subtypes on the basis of their differentiation states, each harboring a unique tumor-initiating population. 相似文献
59.
Tolentino ES Centurion BS Tjioe KC Casaroto AR Tobouti PL Frederigue Junior U Lara VS Damante JH Sant'ana E Gonçales ES 《Oral surgery, oral medicine, oral pathology and oral radiology》2012,113(6):e40-e45
Juvenile ossifying fibroma (JOF) is a rare fibro-osseous neoplasm, defined as a variant of the ossifying fibroma that arises within the craniofacial bones. Two subgroups, juvenile psammomatoid ossifying fibroma (PsJOF) and juvenile trabecular ossifying fibroma, have been delineated by their histology. PsJOF occurs predominantly in the sinonasal and orbital bones. This work reports on 2 cases of extensive PsJOF in the body of the right mandible as well as reviews the literature regarding the radiographic and histologic features, treatment, and prognosis of PsJOF of the jaws. 相似文献
60.
Marques DN da Mata AD Silveira JM Marques JR Amaral JP Guilherme NF 《Clinical oral investigations》2012,16(1):155-163
The objective of this study is to compare salivary hydrogen peroxide (HP) release kinetics and potential toxicity of systemic
exposure of four different whitening products. A double-blind, randomized controlled trial was conducted in a Portuguese dental
faculty clinic. Two hundred forty volunteers were randomized to eight intervention groups. Participants were randomly assigned
to receive active or placebo applications of one of four different products: Opalescence 10% PF™ (OPL), Vivastyle? 10%™ (VS10%),
Vivadent Paint On Plus™ (PO+), and Trés White Supreme™ (TWS). Saliva collection was obtained by established methods at different
times. The HP salivary content was determined by a photometric method. Salivary HP variations, total amount of salivary HP,
and counts of subjects above the safe daily HP dose were the main outcome measures. All whitening systems significantly released
HP to the saliva when compared to placebo, and all showed different release kinetics. The adaptable tray system (TWS) presented
a risk increase of 37% [20–54%, 95% confidence interval] when compared to the other systems. The use of an adaptable tray
whitening system with higher concentration of HP increases the toxicity potential. 相似文献