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981.
982.
Rogers MW Kennedy R Palmer S Pawar M Reising M Martinez KM Simuni T Zhang Y MacKinnon CD 《Journal of neurophysiology》2011,106(2):915-924
People with Parkinson's disease (PD) frequently have difficulties with generating anticipatory postural adjustments (APAs) for forward propulsion and lateral weight transfer when initiating gait. This impairment has been attributed to deficits in motor planning and preparation. This study examined the preparation of APAs prior to an imperative cue to initiate forward stepping. A startling acoustic stimulus (SAS) was used to probe the state of preparation of the APA in eight PD (off medication) and seven matched control subjects. Subjects performed visually cued trials involving a pre-cue light instructing them to prepare to step, followed 3.5 s later by a go-cue light to rapidly initiate stepping. In random trials, a SAS (124 dB) was presented at -1,500, -1,000, -500, -250, -100, or 0 ms before the go-cue. Subjects also performed self-initiated steps. Ground reaction forces (GRFs), center of pressure (CoP) changes, and electromyographic (EMG) signals were recorded. The SAS triggered APAs in 94 ± 11% (PD) and 96 ± 8% (control) of trials at latencies 89 ± 4 ms (PD) and 97 ± 3 ms (control) earlier than Control trials. The temporal profile of APA preparation was similar between groups. However, peak EMG, GRF, and mediolateral CoP amplitudes were reduced in PD. SAS-evoked APAs at 0 ms matched Control trial APAs and were enhanced compared with self-initiated stepping. These results demonstrate that people with mild to moderate PD can plan and prepare the appropriate APA sequence prior to the expected cue to initiate gait; however, the prepared APAs are underscaled in magnitude. 相似文献
983.
984.
Zeiger RS Mauger D Bacharier LB Guilbert TW Martinez FD Lemanske RF Strunk RC Covar R Szefler SJ Boehmer S Jackson DJ Sorkness CA Gern JE Kelly HW Friedman NJ Mellon MH Schatz M Morgan WJ Chinchilli VM Raissy HH Bade E Malka-Rais J Beigelman A Taussig LM;CARE Network of the National Heart Lung Blood Institute 《The New England journal of medicine》2011,365(21):1990-2001
985.
986.
Creatinine reabsorption by the aged kidney 总被引:1,自引:1,他引:0
Carlos G. Musso Hernán Michelángelo Manuel Vilas Juliana Reynaldi Bernardo Martinez Luis Algranati Juan F. Macías Núñez 《International urology and nephrology》2009,41(3):727-731
Aim The handling of renal creatinine in human beings has classically been described as the result of two particular physiological
processes: glomerular filtration and proximal tubular secretion. However, there are particular physiological situations in
which tubular creatinine reabsorption has been documented, such as in the case of healthy newborns and premature babies. We
performed a prospective study in order to evaluate if there is tubular creatinine reabsorption in healthy elderly people.
Patients and method We studied prospectively nine healthy volunteers, four of them young (20–33 years old) and the remaining five, old (65–73 years
old). Since creatinine is secreted in the proximal tubules, and its secretion can be completely blocked by cimetidine administration,
a creatinine clearance with cimetidine reliably represents the glomerular filtration rate. Therefore, if the ratio creatinine
clearance (Ccr)/creatinine clearance with cimetidine (CcrWC) is higher than one, this would indicate net creatinine secretion,
whereas a ratio lower than one would indicate a net renal creatinine tubular reabsorption; a ratio equal to one indicates
creatinine filtration. Finally, the Ccr, CcrWC, and Ccr/CcrWC ratios were compared between the young and old group.
Statistical tests Mann-Whitney and Wilcoxon tests were used.
Results As expected, creatinine clearance in the elderly was significantly lower than in the young [Ccr: 74.4 ml/min (47.9–100.9)
(old) vs. 153.8 ml/min (108.3–199.2) (young), p = 0.014]. Similarly, the creatinine clearance with cimetidine (CcrWC) was significantly lower in the elderly compared to
the young [CcrWC: 81.8 ml/min (69.2–94.5) (old) vs. 122.5 ml/min (82.6–162.4) (young), p = 0.028]. The ratio of Ccr/CcrWC was 0.9 in the elderly vs. 1.26 in the young (p = 0.014), indicating net creatinine reabsorption in the elderly and net creatinine secretion in the young.
Conclusion Our findings indicate that there seems to be a net reabsorption of creatinine in the renal tubules of healthy old persons. 相似文献
987.
Jose A. Morales‐Garcia Rosario Luna‐Medina Ana Martinez Angel Santos Ana Perez‐Castillo 《Journal of neuroscience research》2009,87(16):3687-3696
Kainic acid (KA)‐induced status epilepticus (SE) is a well‐characterized model of excitotoxic neuronal injury. Excitotoxicity results from activation of specific glutamate receptors, with resultant elevation of intracellular Ca2+. The CA1 and CA3 subregions of the hippocampus are especially vulnerable to KA, and this pattern of neuronal injury resembles that occurring in patients with temporal lobe epilepsy. Calcium plays an essential role in excitotoxicity, and accordingly calcium channel inhibitors have been shown to have protective effects in various experimental models of epilepsy and brain injury. Moreover, they also potentiate the antiseizure efficacy of conventional antiepileptic drugs. This study was undertaken to determine whether NP04634, a novel compound, reported as a non‐L‐type voltage‐sensitive calcium channel (VSCC) inhibitor, could prevent the entrance in SE and the neuronal loss evoked by intraperitoneal injection of KA. Our results show that intragastrical administration of NP04634 reduced the percentage of rats that entered SE after KA injection, increased the latency of SE entry, and significantly reduced the mortality of rats that entered SE. Also, NP04634 prevented the loss of hippocampal CA1 and CA3 pyramidal neurons and reduced the gliosis induced by KA. These results point to a potential anticonvulsant and neuroprotective role for NP04634. © 2009 Wiley‐Liss, Inc. 相似文献
988.
Holger Honig MD Angelo Antonini MD Pablo Martinez‐Martin MD Ian Forgacs FRCP Guy C. Faye FRCP Thomas Fox MD Karen Fox MD Francesca Mancini MD Margherita Canesi MD Per Odin MD PhD K. Ray Chaudhuri MD FRCP DSc 《Movement disorders》2009,24(10):1468-1474
Switching from oral medications to continuous infusion of levodopa/carbidopa gel reduces motor complications in advanced Parkinson's disease (PD), but effects on nonmotor symptoms (NMSs) are unknown. In this prospective open‐label observational study, we report the effects of intrajejunal levodopa/carbidopa gel infusion on NMS in PD based on standard assessments utilizing the nonmotor symptoms scale (NMSS) along with the unified Parkinson's disease rating scale (UPDRS 3 motor and 4 complications) and quality of life (QoL) using the Parkinson's disease questionnaire (PDQ‐8). Twenty‐two advanced PD patients (mean age 58.6 years, duration of disease 15.3 years) were followed for 6 months. A statistically significant beneficial effect was shown in six of the nine domains of the NMSS: cardiovascular, sleep/fatigue, attention/memory, gastrointestinal, urinary, and miscellaneous (including pain and dribbling) and for the total score of this scale (NMSST) paralleling improvement of motor symptoms (UPDRS 3 motor and 4 complications in “best on” state) and dyskinesias/motor fluctuations. In addition, significant improvements were found using the Parkinson's disease sleep scale (PDSS) and the PDQ‐8 (QoL). The improvement in PDQ‐8 scores correlated highly significantly with the changes in NMSST, whereas a moderately strong correlation was observed with UPDRS changes. This is the first demonstration that a levodopa‐based continuous dopaminergic stimulation is beneficial for NMS and health‐related quality of life in PD in addition to the reduction of motor fluctuations and dyskinesias. © 2009 Movement Disorder Society 相似文献
989.
A. Loupy C. Suberbielle-Boissel G. S. Hill C. Lefaucheur D. Anglicheau J. Zuber F. Martinez E. Thervet A. Méjean D. Charron J. P. Duong van Huyen P. Bruneval C. Legendre D. Nochy 《American journal of transplantation》2009,9(11):2561-2570
This study describes clinical relevance of subclinical antibody-mediated rejection (SAMR) in a cohort of 54 DSA-positive kidney transplant recipients receiving a deceased donor. In 3 months screening biopsies, 31.1% of patients met the criteria of SAMR. A total of 48.9% had an incomplete form of SAMR (g+/ptc+/C4d-negative) whereas 20% had no humoral lesions. Patients with SAMR at 3 months had at 1 year: a higher C4d score, ptc score, and arteriosclerosis score, higher rate of IFTA (100% vs. 33.3%, p < 0.01) and a higher rate of transplant glomerulopathy (43% vs. 0%, p = 0.02) compared to patients without 3-month SAMR. Patients with SAMR at 3 months exhibited at 1 year a higher class II MFImax-DSA and a lower mGFR compared to patients without SAMR (39.2 ± 13.9 vs. 61.9 ± 19.2 mL/min/1.73 m2 respectively, p < 0.01). The group of patients with C4d-negative SAMR at 3 months developed more ptc and IFTA lesions, and lower GFR at 1 year in comparison to biopsies without humoral lesions. SAMR is a frequent entity in KTR with preexisting DSAs and promotes subsequent GFR impairment and development of chronic AMR. C4d-negative SAMR patients displayed an intermediate course between the no-SAMR group and the C4d+ SAMR group. Screening biopsies may be useful to recognize patients more likely to develop SAMR. 相似文献
990.
Jorge Berlanga‐Acosta Jorge Gavilondo‐Cowley Pedro López‐Saura Tania González‐López María D Castro‐Santana Ernesto López‐Mola Gerardo Guillén‐Nieto Luis Herrera‐Martinez 《International wound journal》2009,6(5):331-346
Chemotaxis, mitogenesis, motogenesis and cytoprotection are common cellular events involved in both tumourigenesis and tissue repair, which appear amplified upon growth factors exposure. Epidermal growth factor (EGF) promotes these events in epithelial and mesenchymal cells through the binding to a specific tyrosine kinase receptor. In experimental oncology settings, EGF does not initiate malignant transformation but exhibits ‘tumour promotion’. These observations have raised doubts on the clinical use of EGF despite solid demonstrations of efficacy in experimental conditions and clinical trials. The results of a Pubmed and Bioline investigation on EGF clinical uses and preclinical safety data are presented here. EGF topical administration has been used since 1989 to enhance the healing process of a variety of peripheral tissues wounds (16 clinical reports), as well as its intravenous, oral and rectal administration for gastrointestinal damages (11 clinical reports). EGF therapeutic efficacy and excellent tolerability seem demonstrated. Lack of long‐term adverse effects is highlighted in those studies with 6, 12 and 24 months of patients follow‐up. Although post‐treatment follow‐up may fall short for malignant growth, there are no reports on evidences linking EGF clinical use with cancer. A multicentre, nationwide survey in Cuba, 15 years after randomly using silver sulphadiazine with EGF or not in burn victims yielded that cancer incidence was comparable between EGF‐treated and control subjects and that such incidence rate does not differ from the age‐matched national incidence for those 15‐year period. All the animal species subjected to long‐term EGF systemic administration exhibit dose‐dependent and reversible epithelial organs hyperplasia with no changes in cells phenotypic differentiation. Histotypic pre‐malignant markers were not identified. The results emerged from co‐carcinogenesis studies and from transgenic mice over‐expressing EGF are conflicting and indicate that EGF overexposure, either innate or postnatal, may not be sufficient to transform cells. The ability of EGF to heal injured tissues in life‐threatening scenarios or to assist in preventing physical and social disability advocates for its clinical use under a rational medical risk/benefit balance. 相似文献