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41.
M Ben Farhat F Maatouk F Betbout M Ayari H Brahim M Souissi K Sghairi H Gamra 《European heart journal》1992,13(12):1658-1664
Normal gestation is associated with a hyperdynamic adaptive state. The circulatory changes represent an additional burden on the cardiovascular system of women with rheumatic mitral stenosis (MS). Life-threatening complications can occur in pregnant women with severe MS. We successfully performed percutaneous balloon mitral valvotomy (PMV) in eight pregnant patients (mean age 28 +/- 6.9 years, range 21-38 years). Pregnancy mean age was 24.6 +/- 6.5 weeks. Five patients were in NYHA functional class III and three patients were in class IV. Emergency PMV seemed to be life saving to both mother and foetus in one case. All patients but one had pliable valves. PMV was achieved using the double balloon transseptal technique. To protect the foetus from radiation, the patient's pelvic-abdominal area was shielded and left ventriculography was not performed. The total mean time of PMV was 72 +/- 19 min and that of fluoroscopy was 16.6 +/- 7.8 min. Gorlin's mitral valve area increased from 0.83 +/- 0.15 to 2.4 +/- 0.34 cm2 and the cardiac index from 3.1 +/- 0.77 to 4.2 +/- 0.79 l.min-1.m-2. Left atrium pressure decreased from 29 +/- 10 to 14 +/- 5 mmHg and mitral valve gradient from 21 +/- 7 to 6 +/- 3 mmHg. There were no complications or residual MS. At a mean follow-up of 13.2 +/- 9.4 months, all patients were in NYHA class I and had a normal course of pregnancy. The eight women delivered healthy full-term babies. At 1-25 months post-partum follow-up, the eight infants had shown normal growth and development.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
42.
Naughton BJ Saltzman S Ramadan F Chadha N Priore R Mylotte JM 《Journal of the American Geriatrics Society》2005,53(1):18-23
OBJECTIVES: To improve outcomes for cognitively impaired and delirious older adults. DESIGN: Pretest, posttest. SETTING: A university-affiliated hospital. PARTICIPANTS: Physicians and nurses in the emergency department (ED) and on an acute geriatric unit (AGU). INTERVENTION: Multifactorial and targeted to the processes of care for cognitively impaired and delirious older adults admitted to medicine service from the ED. MEASUREMENTS: Prevalence of delirium, admission to AGU, psychotropic medication use, hospital length of stay. RESULTS: Patient characteristics did not differ between baseline and the two outcome cohorts 4 and 9 months postintervention. Prevalence of delirium was 40.9% at baseline, 22.7% at 4 months (P<.002), and 19.1% at 9 months (P<.001). More delirious patients were admitted to the AGU than to non-AGU units at 4 months (P<.01) and 9 months (P<.01). Postintervention medication use in the hospital differed from baseline. Antidepressant use was greater at 4 months (P<.05). Benzodiazepine and antihistamine use were lower at 9 months (P>.01). Antidepressant and neuroleptic use were higher (P<.02) and antihistamine use was lower (P<.02) at 4 months on the AGU than for the baseline group. Benzodiazepine (P<.01) and antihistamine (P<.05) use were lower at 9 months. Each case of delirium prevented saved a mean of 3.42 hospital days. CONCLUSION: A multifactorial intervention designed to reduce delirium in older adults was associated with improved psychotropic medication use, less delirium, and hospital savings. 相似文献
43.
Nass RD Aiba T Tomaselli GF Akar FG 《Nature clinical practice. Cardiovascular medicine》2008,5(4):196-207
In an attempt to compensate for compromised hemodynamics in heart failure, neurohumoral mechanisms are activated that trigger fundamental changes in gene expression and in protein processing, trafficking and post-translational regulation, resulting in myocyte hypertrophy. Unfortunately, over time these changes become maladaptive, predisposing to myocyte loss, chamber dilatation, interstitial hyperplasia and intercellular uncoupling. Intrinsic and peripheral responses to mechanical dysfunction alter the expression and function of key ion channels and calcium-handling proteins, thereby remodeling the cellular action potential and the intracellular calcium transient. This electrophysiological remodeling renders the heart more vulnerable to ventricular arrhythmias that underlie sudden cardiac death. In this Review, we consider key ventricular ionic changes that are associated with heart failure, with the intention of identifying molecular targets for antiarrhythmic therapy. 相似文献
44.
Mohammad Khalid Parvez Deepak Sehgal Shiv Kumar Sarin Seemi Farhat Basir Shahid Jameel 《World journal of gastroenterology : WJG》2006,12(19)
AIM: To evaluate the in vitro anti-HBV activity of recombinant human IFN-γ, alone and in combination with lamivudine.METHODS: A recombinant baculovirus-HBV/HepG2 culture system was developed which could support productive HBV infection in vitro. Expression of HBsAg and HBeAg in infected HepG2 culture medium was detected by commercial enzyme immunoassays. HBV DNA replication intermediates were detected in infected cells by Southern hybridization and viral DNA load was determined by dot hybridization.RESULTS: IFN-γ at 0.1 to 5 μg/L efficiently down regulated HBsAg expression in transduced HepG2 cells.At 5 μg/L, IFN-γ also suppressed HBV DNA replication in these cells. While treatment with a combination of lamivudine and IFN-γ showed no additive effect,sequential treatment first with lamivudine and then IFN-γ was found to be promising. In this culture system the best HBV suppression was observed with a pulse of 2 μmol/L lamivudine for two days, followed by 1 μg/L IFN-γ for another four days. Compared to treatment with lamivudine alone, the sequential use of 0.2 μmol/L lamivudine for two days, followed by 5 μg/L IFN-γ for six days showed a 72% reduction in HBV cccDNA pool.CONCLUSION: This in vitro study warrants further evaluation of a combination of IFN-γ and lamivudine,especially in IFN-α non-responder chronic hepatitis B patients. A reduced duration of lamivudine treatment would also restrict the emergence of drug-resistant HBV mutants. 相似文献
45.
Nadim El-Awar Anh Nguyen Khalid Almeshari Moheeb Alawami Fadi Alzayer Maha Alharbi Nori Sasaki Paul I. Terasaki 《Human immunology》2013
Donor-specific antibodies (DSA) in sera of sensitized transplant patients are often produced against the specific epitopes on mismatched HLA antigens. In this study, we selected sera from 30 kidney transplant patients with DSA and AMR to define DQ epitopes. Using adsorption and elution assays, we identified 18 antibody reaction patterns to define 6 new epitopes and to confirm 12 previously defined epitopes. In one patient case, one mismatched antigen produced 3 different antibodies and, in another, antibodies were produced against the alpha and beta chains of the same antigen. For some sera, a single epitope can explain reactions for 27 of the 29 DQ beads in the single antigen panel. 相似文献
46.
Aymen Mouelhi Mounir Sayadi Farhat Fnaiech Karima Mrad Khaled Ben Romdhane 《Computers in biology and medicine》2013,43(12):2263-2277
Manual assessment of estrogen receptors′ (ER) status from breast tissue microscopy images is a subjective, time consuming and error prone process. Automatic image analysis methods offer the possibility to obtain consistent, objective and rapid diagnoses of histopathology specimens. In breast cancer biopsies immunohistochemically (IHC) stained for ER, cancer cell nuclei present a large variety in their characteristics that bring various difficulties for traditional image analysis methods. In this paper, we propose a new automatic method to perform both segmentation and classification of breast cell nuclei in order to give quantitative assessment and uniform indicators of IHC staining that will help pathologists in their diagnostic. Firstly, a color geometric active contour model incorporating a spatial fuzzy clustering algorithm is proposed to detect the contours of all cell nuclei in the image. Secondly, overlapping and touching nuclei are separated using an improved watershed algorithm based on a concave vertex graph. Finally, to identify positive and negative stained nuclei, all the segmented nuclei are classified into five categories according to their staining intensity and morphological features using a trained multilayer neural network combined with Fisher's linear discriminant preprocessing. The proposed method is tested on a large dataset containing several breast tissue images with different levels of malignancy. The experimental results show high agreement between the results of the method and ground-truth from the pathologist panel. Furthermore, a comparative study versus existing techniques is presented in order to demonstrate the efficiency and the superiority of the proposed method. 相似文献
47.
Amy L. Schneider Candace T. Myers Alison M. Muir Sophie Calvert Alice Basinger M. Scott Perry Lance Rodan Katherine L. Helbig Chelsea Chambers Kathleen M. Gorman Mary D. King Sandra Donkervoort Ariane Soldatos Carsten G. Bnnemann Nino Spataro Elisabeth Gabau Montserrat Arellano Gerarda Cappuccio Nicola Brunetti‐Pierri Elsa Rossignol Fadi F. Hamdan Jacques L. Michaud Christopher Balak Heather C. Mefford Ingrid E. Scheffer 《Epilepsia》2021,62(1):e13-e21
Chromosome 1q41‐q42 deletion syndrome is a rare cause of intellectual disability, seizures, dysmorphology, and multiple anomalies. Two genes in the 1q41‐q42 microdeletion, WDR26 and FBXO28, have been implicated in monogenic disease. Patients with WDR26 encephalopathy overlap clinically with those with 1q41‐q42 deletion syndrome, whereas only one patient with FBXO28 encephalopathy has been described. Seizures are a prominent feature of 1q41‐q42 deletion syndrome; therefore, we hypothesized that pathogenic FBXO28 variants cause developmental and epileptic encephalopathies (DEEs). We describe nine new patients with FBXO28 pathogenic variants (four missense, including one recurrent, three nonsense, and one frameshift) and analyze all 10 known cases to delineate the phenotypic spectrum. All patients had epilepsy and 9 of 10 had DEE, including infantile spasms (3) and a progressive myoclonic epilepsy (1). Median age at seizure onset was 22.5 months (range 8 months to 5 years). Nine of 10 patients had intellectual disability, which was profound in six of nine and severe in three of nine. Movement disorders occurred in eight of 10 patients, six of 10 had hypotonia, four of 10 had acquired microcephaly, and five of 10 had dysmorphic features, albeit different to those typically seen in 1q41‐q42 deletion syndrome and WDR26 encephalopathy. We distinguish FBXO28 encephalopathy from both of these disorders with more severe intellectual impairment, drug‐resistant epilepsy, and hyperkinetic movement disorders. 相似文献
48.
49.
David Landzberg Raul G. Nogueira Alhamza R. Al-Bayati Song Julia Kim Mehdi Bouslama Leonardo Pisani Catarina Perry da Camara Michael Frankel Fadi B. Nahab Nicolas Bianchi Diogo C. Haussen 《Journal of stroke and cerebrovascular diseases》2021,30(8):105823
Background and purposeThe baseline characteristics of patients with symptomatic carotid web (CaW) are unclear. We investigate demographic and cerebrovascular risk factors in patients with this overlooked stroke etiology.MethodsWe identified consecutive patients diagnosed with symptomatic CaW at a comprehensive stroke center from July 2014-December 2018. These patients were matched at a 1:4 ratio (based on age and NIHSS scores) to create a control group of acute ischemic stroke (AIS) patients with non-CaW etiologies from the local GetWithTheGuidelines stroke database.ResultsThirty patients with symptomatic CaW were compared to 120 AIS patients with non-CaW etiologies. Symptomatic CaW patients were more likely to be female (73.3 vs. 44.2%; p = 0.004) and black (86.7 vs. 64.2%; p = 0.02). Symptomatic CaWs patients had a fewer absolute number of modifiable cerebrovascular risk factors (1.7±1.1 vs. 2.5±1.2; p = 0.002), lower rates of hypertension (43.4 vs. 63.3%; p = 0.04), and a more favorable lipid profile with lower average LDL (89.5±30.3 vs. 111.2±43.7 mg/dL; p = 0.01) and higher average HDL (47.9±11.3 vs. 42.2±13.8 mg/dL; p = 0.01) as compared to strokes with non-CaW etiology. Symptomatic CaW patients were more likely to have a large vessel occlusion (80.0 vs. 51.7%; p = 0.005), despite similar e-ASPECTS between the groups (8.1±2.1 vs. 8.3±2.2; p = 0.30). On multivariable analysis, symptomatic CaW was an independent predictor of independence at discharge (OR 3.72; 95%CI 1.27–10.94).ConclusionA gender and racial predilection of symptomatic CaWs may exist as females and blacks were were found to be more likely affected. Symptomatic CaW patients have a more benign cerebrovascular risk factor profile corroborating the proposed mechanism of local stasis and thromboembolism. Despite presenting more commonly with LVO, symptomatic CaW was associated with good functional outcome, warranting further studies. 相似文献
50.
Fadi Seif Sanjay R. Patel Harneet Walia Michael Rueschman Deepak L. Bhatt Daniel J. Gottlieb Eldrin F. Lewis Susheel P. Patil Naresh M. Punjabi Denise C. Babineau Susan Redline Reena Mehra 《Journal of sleep research》2013,22(4):443-451
The objective of this study is to examine whether increasing obstructive sleep apnea (OSA) severity is associated with worsening endothelial function. The design is a cross‐sectional examination of the baseline assessment of a multi‐centre randomized controlled clinical trial examining the effects of oxygen, continuous positive airway pressure (CPAP) therapy or lifestyle modifications on cardiovascular biomarkers. Participants were recruited from cardiology clinics at four sites. Participants with an apnea–hypopnea index (AHI) of 15–50 and known cardio/cerebrovascular disease (CVD) or CVD risk factors were included. OSA severity indices [oxygen desaturation index (ODI), AHI and percentage of sleep time below 90% oxygen saturation (total sleep time <90)] and a measure of endothelium‐mediated vasodilatation [Framingham reactive hyperaemia index (F‐RHI) derived from peripheral arterial tonometry (PAT)] were assessed. The sample included 267 individuals with a mean AHI of 25.0 ± 8.5 SD and mean F‐RHI 0.44 ± 0.38. In adjusted models, the slope of the relationship between ODI and F‐RHI differed above and below an ODI of 24.6 (P = 0.04), such that above an ODI of 24.6 there was a marginally significant decline in the geometric mean of the PAT ratio by 3% [95% confidence interval (CI): 0%, 5%; P = 0.05], while below this point, there was a marginally significant incline in the geometric mean of the PAT ratio by 13% (95% CI: 0%, 27%; P = 0.05) per 5‐unit increase in ODI. A similar pattern was observed between AHI and F‐RHI. No relation was noted with total sleep time <90 and F‐RHI. There was evidence of a graded decline in endothelial function in association with higher levels of intermittent hypoxaemia. 相似文献