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32.
Dr. Michèle Gue BS Jean Fioramonti DS Jacques Frexinos MD M. Alvinerie BS Lionel Bueno DS 《Digestive diseases and sciences》1987,32(12):1411-1417
The effects of acoustic stress (AS) on gastrointestinal motility and their prevention by previous treatment with naloxone, phentolamine, propranolol, muscimol, and diazepam were investigated in intact and vagotomized fasted dogs fitted with chronically implanted strain gauges on the antrum at 10 cm from pylorus and on the jejunum at 70 and 140 cm from the pylorus. These effects were compared to those produced by intracerebroventricular administration of ovine corticotropin releasing factor (oCRF). Beginning 40–50 min after the occurrence of a gastric migrating motor complex (MMC), a 1-hr hearing of prerecorded intense music through earpieces (<100 dB) delayed the occurrence of the next gastric MMC observed after 2.8±1.2 hr, while jejunal MMC were still present at a normal frequency. During AS, heart rate and plasma cortisol were significantly increased by 32.7 and 215%, respectively, 10–15 min after the beginning of hearing. The AS-induced lengthening of the gastric MMC cycle as well as cortisol increase were abolished after previous administration of diazepam (0.5 mg/kg intramuscular) or muscimol (10 g/kg intravenous), while they were still present after naloxone (0.1 mg/kg intravenous), phentolamine (0.2 mg/kg intravenous), or propranolol (0.1 mg/kg intravenous). CRF administered intracerebroventricularly (100 ng/kg) also delayed the occurrence of gastric MMC without affecting jejunal motility, and this effect was not antagonized by previous treatment with diazepam or muscimol. Both the effects of AS and CRF were abolished after bilateral thoracic vagotomy. These results suggest that the selective inhibition of gastric motility induced by noise in dog is due to the CNS release of CRF which affects, in turn, the vagal output to the stomach. The suppressive action of diazepam or GABA agonist on noise-induced gastric hypomotility may be related to blockade of the AS-induced CRF release. 相似文献
33.
Samiran Upadhyaya Achyut Konwar Devasish Chowdhury Neelotpal Sen Sarma 《RSC advances》2020,10(43):25408
Water-borne adhesives have immense importance in cellulose-based materials, where their durability, handling, and strength remain to be a major concern. The present work demonstrates the development of three water-borne adhesives, namely, poly(1-vinyl-2-pyrrolidone-co-acrylic acid), poly(acrylonitrile-co-acrylic acid), and poly(1-vinyl-2-pyrrolidone-co-acrylonitrile-co-acrylic acid) applicable for cellulose-based materials. These acrylic-acid based adhesives were characterized by Fourier-transform infra-red spectroscopy, thermogravimetric analysis, X-ray diffraction, gel permeation chromatography, and universal testing machine. The synthesized polymer adhesives can be stored in the powder form for a longer period, thus utilizing less space. In order to use as adhesives, suitable formulations can be prepared in water. The adhesives show thermal stability up to 300 °C. Our studies show that poly(1-vinyl-2-pyrrolidone-co-acrylonitrile-co-acrylic acid) showed higher lap shear strength (ASTM D-906) than commercially available adhesives. In addition, these adhesives, being fluorescent in nature, can be detected under UV light and thus are applicable for the detection of fractured joints of any specimen. This property also helps in anti-counterfeiting applications, thus adding further to their utility.Synthesis and application of a water-borne fluorescent acrylic adhesive, which can be stored as a powder for long-term use. 相似文献
34.
Gabriele?Donati Maria?Ilaria?Moretti Olga?Baraldi Alessandra?Spazzoli Irene?Capelli Giorgia?Comai Antonio?Marchetti Maria?Sarma Rita?Mancini Gaetano?La MannaEmail author 《BMC nephrology》2016,17(1):193
Background
Immunoglobulin light chains are classified as middle molecule uremic toxins able to interact with B lymphocyte membranes leading to the activation of transmembrane signaling. The ensuing impairment of neutrophil function can contribute to the chronic inflammation state of uremic patients, and the increased risk of bacterial infections or vascular calcifications. The aim of this crossover observational study was to assess the difference in free light chain removal by three different hemodialysis filters in patients not affected by multiple myeloma.Methods
Free light chain removal was compared in the polymethylmethacrylate (PMMA) membrane Filtryzer BK-F, the polyphenylene HFR17 filter and the conventional polysulfone filter F7HPS. Twenty chronic hemodialysis patients were enrolled: mean age was 67.7?±?17.0 years, M/F?=?14/6, dialysis vintage (months) 25.5?±?32.0. The patients were randomized into two groups of treatment lasting 6 weeks each. The dialysis sessions checked were the midweek sessions and the blood was drawn at times 0, 120’ and 240’. Kappa (k) and lambda (λ) light chain levels, β2microglobulin (β2M), C reactive protein (CRP) and albumin were checked.Results
K light chain levels were 345.0?±?100.0 mg/L, λ light chains were 121.4?±?27.0 mg/L. The values of k light chains at times 120’ and 240’ were significantly lower with PMMA and HFR17 than those obtained with F7. The reduction ratio per session (RRs) for k light chains was 44.1?±?4.3% with HFR17, 55.3?±?3.4% with PMMA, 25.7?±?8.3% with F7 (p?=?0.018). The RRs for λ light chains was 30.3?±?2.9% with HFR17, 37.8?±?17.3% with PMMA, 14.0?±?3.9% with F7 (p?=?0.032). As to β2M, RRs was 42.4?±?3.2% with HFR17 vs. 33.9?±?2.8% with PMMA vs. 6.3?±?1.9% with F7 (p?=?0.022). The three filters tested showed no differences in CRP or albumin levels.Conclusion
In terms of light chain and β2M removal, the PMMA and on-line HFR filters are similar and both are significantly more effective than the F7 filter in chronic dialysis patients.Trial registration
The present trial was registered retrospectively (NCT02950389, 31/10/2016).35.
36.
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38.
Background
Rhabdomyolysis (RML) is a rare complication of bariatric surgery. A systematic review was performed to identify risk factors and patient outcomes in morbidly obese patients undergoing bariatric surgery who develop RML.Methods
A comprehensive search was performed between January 1990 and March 2012 using relevant MeSH terms. Studies were chosen based on predefined inclusion criteria. RML was defined as a creatine kinase of more than 1,000 IU/L. The parameters assessed included patient characteristics of the RML population, type of bariatric surgery performed, operating time, complications, presentation and diagnosis of RML.Results
Twenty-two studies were analysed which included 11 case reports, two case series, six prospective and three retrospective comparative studies. Overall 145 patients with RML were reported following bariatric surgery. Acute renal failure was found in 20 patients (14 %) and was significantly more likely to occur in patients with postoperative muscle pain (p?<?0.05). The mortality rate after renal failure was 25 % (n?=?5). In the comparative studies, 87 RML patients were compared with 325 non-RML patients. The RML patients were more likely to be male, had a greater mean body mass index (BMI) (52 vs 48 kg/m2, p?<?0.01) and underwent a longer operation (255 vs 207 min, p?<?0.01) compared to non-RML patients.Conclusions
Risk factors of developing RML following bariatric surgery include male gender, elevated BMI and prolonged operating time. Patients with a biochemical diagnosis of RML and postoperative myalgia after bariatric surgery are at increased risk of developing acute renal failure and mortality. These patients must be identified and treated promptly. 相似文献39.
Divyata R. Hingwala Chandrasekharan Kesavadas Bejoy Thomas Tirur R. Kapilamoorthy P. Sankara Sarma 《Annals of Indian Academy of Neurology》2013,16(2):229-233
Background:
The purpose of this study was to evaluate the difference in the occurrence of the various “traditional” imaging signs of intracranial hypertension (IIH) on magnetic resonance imaging (MRI) in patients with idiopathic (IIH) and secondary intracranial hypertension.Materials and Methods:
In a retrospective analysis, the MRI findings of 21 patients with IIH and 60 patients with secondary intracranial hypertension (41 with tumors; 19 with intracranial venous hypertension) were evaluated for the presence or absence of various “traditional” imaging signs of IIH (perioptic nerve sheath distention, vertical buckling of optic nerve, globe flattening, optic nerve head protrusion and empty sella) using the Fisher’s exact test. Odds ratios were also calculated. Statistical Package for the Social Sciences version 17.0 was used for statistical analysis. Subgroup analysis of the IIH versus tumors and IIH versus venous hypertension were performed.Results:
Optic nerve head protrusion and globe flattening were significantly associated with IIH. There was no statistically significant difference in the occurrence of rest of the findings. On subgroup analysis, globe flattening and optic nerve head protrusion occurred significantly more often in IIH than in tumors. However, there was no statistically significant difference in the occurrence of any of these findings in patients with IIH and venous hypertension.Conclusions:
IIH is a diagnosis of exclusion. While secondary causes of raised intracranial pressure (ICP) have obvious clinical findings on MRI, some conditions like cerebral venous thrombosis may have subtle signs and differentiating between primary and secondary causes may be difficult. In the absence of any evident cause of raised ICP, presence of optic nerve head protrusion or globe flattening can suggest the diagnosis of IIH. 相似文献40.
Laura Dwyer-Lindgren Ellen R. Squires Stephanie Teeple Gloria Ikilezi D. Allen Roberts Danny V. Colombara Sarah Katherine Allen Stanley M. Kamande Nicholas Graetz Abraham D. Flaxman Charbel El Bcheraoui Kristjana Asbjornsdottir Gilbert Asiimwe Ângelo Augusto Orvalho Augusto Baltazar Chilundo Caroline De Schacht Sarah Gimbel Carol Kamya Faith Namugaya Felix Masiye Cremildo Mauieia Yodé Miangotar Honoré Mimche Acácio Sabonete Haribondhu Sarma Kenneth Sherr Moses Simuyemba Aaron Chisha Sinyangwe Jasim Uddin Bradley H. Wagenaar Stephen S. Lim 《Population health metrics》2018,16(1):13