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981.
982.
Luis Fernando Sousa Filho Paula P. Menezes Dayanne Valéria Soares Santana Bruno S. Lima Shanmugan Saravanan Grace Kelly M. Almeida José Evaldo R. Menezes Filho Marta M.B. Santos Adriano Antunes S. Araújo Evaleide Diniz de Oliveira 《Ultrasound in medicine & biology》2018,44(2):359-367
Cyclodextrins (CDs) have been widely used as a promising alternative in the formation of inclusion complexes with poorly soluble molecules. From this perspective, the present study aimed to study the inclusion complexes of diosmin in β-cyclodextrin, chemically quantify the diosmin-in-gel preparation and analyze the stability of the gels. Furthermore, we evaluated the effect of therapeutic pulsed ultrasound (TPU) in association with the gel–diosmin complex on the parameters of muscle damage and oxidative stress in rats. Serum creatine kinase (CK) levels were used as an indicator of skeletal muscle injury. Lipid peroxidation (thiobarbituric acid-reactive substances [TBARS]) and superoxide dismutase and catalase activities were used as indicators of oxidative stress. The results obtained indicated that the inclusion complex obtained by co-evaporation had the highest complexation efficiency and stability; there was no change in the features of diosmin on incorporation into the Carbopol gel. Additionally, a significant (p?<0.05) decrease was observed in CK levels (TPU?plus gel-diosmin: 178.4?±?85.3?U/L) relative to the untreated group (527.8?±?46.1?U/L). Levels of TBARS were lower in the TPU?plus gel-diosmin group (0.008?±?0.0004?nmol malondialdehyde/mg protein, p?<0.05) compared with the untreated group (0.081?±?0.011?nmol malondialdehyde/mg protein, p?<0.05, n?=?6). Catalase activity did not statistically significantly differ between the treatment groups, and superoxide dismutase activity was lower in the diosmin-treated group (0.320?±?0.11?U/mg protein) compared with the untreated group (0.983?±?0.40?U/mg protein). These results suggest that TPU in association with the diosmin–gel complex is effective in reducing muscle damage and oxidative stress after mechanical trauma. 相似文献
983.
Modification of splenic stiffness on acoustic radiation force impulse parallels the variation of portal pressure induced by transjugular intrahepatic portosystemic shunt 下载免费PDF全文
984.
Elidiane Rusch Milena F Bovi Elaine C Martinelli Mariana SA Garcia-Gomes Claudia MC Mori Daniele S Martins Adriano B Carregaro 《Journal of the American Association for Laboratory Animal Science》2021,60(3):349
This study assessed the exploratory behavioral responses in BALB/c mice inoculated with Ehrlich ascitic carcinoma after 3 consecutive days of treatment with morphine or methadone. Fifty-three female mice, 60 ± 10 d old, were used. Seven days after intraperitoneal tumor inoculation (2 × 106 cells), the animals were randomized into 7 groups: morphine 5 mg/kg (MO5), morphine 7.5 mg/kg (MO7.5), morphine 10 mg/kg (MO10), methadone 2.85 mg/kg (ME2.85), methadone 4.3 mg/kg (ME4.3), methadone 5.7 mg/kg (ME5.7), and 0.9% NaCl (Saline) (n = 7). Drug treatments were administered subcutaneously every 6 h for 3 d. The animals were evaluated for analgesia using the mouse grimace scale (MGS) and for general activity using the open field test. The MGS was performed before tumor inoculation (day 0), on day 7 at 40, 90, 150, 240, and 360 min after drug injection, and on days 8 and 9 at 40, 150, 240, and 360 min after drug injection. The open field test was performed before tumor inoculation (day 0), on day 7 after inoculation at 40, 90, 150, 240, and 360 min after drug injection, and on days 8 and 9 after inoculation at 40, 150, and 360 min after drug injection. MGS results indicated that administration of morphine promoted analgesia for up to 240 min. Conversely, methadone reduced MGS scores only at 40 min. All tested doses promoted a significant dose-dependent increase in the total distance traveled and the average speed, and increase that was markedly pronounced on days 8 and 9 as compared with day 7. The frequencies of rearing and self-grooming decreased significantly after morphine or methadone administration. Despite the difference in analgesia, both drugs increased locomotion and reduced the frequency of rearing and self-grooming as compared with the untreated control animals.Ehrlich carcinoma is a well-known transplantable tumor in which cells from mammary adenocarcinoma are inoculated subcutaneously or intraperitoneally, and grow into either solid or ascitic tumors, respectively.6,8 This tumor is considered to cause pain yet is widely used to determine the influence of drugs and other therapeutic substances on the inhibition of tumor growth.23,27,33 The ascitic form of Ehrlich carcinoma is characterized by a proinflammatory response induced by tumor cells in the peritoneum and increased vascular permeability.41 Tumor cells promote a progressive increase in the secretion of interleukin-1β (IL1β),16 monocyte chemoattractant protein-1 (MCP-1)54 and prostaglandin E2 (PGE-2),28 substances all related to the phenomenon of hyperalgesia.15Recognition and management of pain are an important component of international standards designed to ensure the welfare of research animals. These factors are closely related to the survival and quality of life.34,55 Although a test to directly measure pain in animals is currently unavailable, changes in behavioral patterns can indicate pain (for example, agitation, reduced ambulation, and changes in the sequence and frequency of self-grooming and vocalization).9 Opioid analgesics, such as morphine and methadone, although frequently regarded as the most effective treatment of cancer pain,12,38,53 tend to alter locomotor activity and exploratory behavior in mice.22,43,47 Although morphine alters behavioral patterns, it does not interfere with facial expression in the absence of pain.30Morphine is a potent opioid that acts mainly through the occupation of pre- and postsynaptic µ-opioid receptors, which modulate the perception of pain.52 Methadone has affinity for µ-receptors, is also an antagonist of N-methyl-D-Aspartate receptors (NMDA), and is considered an ideal treatment choice in cases of tolerance to morphine.20 The condition of cancer pain requires long-term analgesic treatment. However, some disagreement remains regarding the optimal doses and frequency of administration of morphine and methadone in mice, and few studies have evaluated the effects of these drugs on cancer pain in mice or the effect of long-term administration.35,39,43,46The current study aimed to evaluate the analgesic effect of morphine and methadone in BALB/c mice with Ehrlich ascitic carcinoma by observing the influence of these opioids on behavior. The hypothesis was that morphine and methadone would provide analgesia and mitigate pain-related behavioral changes in mice with Ehrlich ascitic carcinoma in a dose-dependent manner. 相似文献
985.
Comparison of behavioral,neuroprotective, and proinflammatory cytokine modulating effects exercised by (+)‐cis‐EC and (−)‐cis‐EC stereoisomers in a PTZ‐induced kindling test in mice 下载免费PDF全文
Paula Regina Rodrigues Salgado Diogo Vilar da Fonsêca Cynthia Germoglio Farias de Melo Fagner Carvalho Leite Adriano Francisco Alves Paula Benvindo Ferreira Márcia Regina Piuvezam Damião Pergentino de Sousa Reinaldo Nóbrega de Almeida 《Fundamental & clinical pharmacology》2018,32(5):507-515
Epoxy‐carvone (EC) has chiral centers that allow generation of stereoisomers, including (+)‐cis‐EC and (?)‐cis‐EC, whose effects in the kindling tests have never been studied. Accordingly, this study aims to comparatively investigate the effect of stereoisomers (+)‐cis‐epoxy‐carvone and (?)‐cis‐epoxy‐carvone on behavioral changes measured in scores, in the levels of cytokines (IL‐1β, IL‐6, and TNFα) and neuronal protection in the face of continuous treatment with pentylenetetrazol. Swiss mice were divided into five groups (n = 10), receiving vehicle, (+) – cis‐EC, (?) – cis‐EC (both at the dose of 30 mg/kg), and diazepam (4 mg/kg). Thirty minutes after the respective treatment was administered to the animals one subconvulsive dose of PTZ (35 mg/kg). Seven subconvulsives treatments were made on alternate days, in which each treatment several parameters were recorded. In the eighth treatment, the animals receiving the highest dose of PTZ (75 mg/kg) and were sacrificed for quantification of cytokines and histopathologic analysis. All drugs were administered by intraperitoneal route. In the kindling test, (+)‐cis‐EC and (?)‐cis‐EC reduced the average scores. The stereoisomer (+)‐cis‐EC decreased levels of proinflammatory cytokines IL‐1β, IL‐6, and TNFα, whereas comparatively (?)‐cis‐EC did not reduce IL‐1β levels. Histopathological analysis of the mice hippocampi undergoing this methodology showed neural protection for treated with (+)‐cis‐EC. The results suggest that the anticonvulsant effect of (+)‐cis‐EC possibly takes place due to reduction of proinflammatory cytokines involved in the epileptogenic process, besides neuronal protection, yet further investigation of the mechanisms involved is required. 相似文献
986.
Claessen BE Caixeta A Henriques JP Piek JJ 《Expert review of cardiovascular therapy》2010,8(10):1363-1374
The introduction of drug-eluting stents has led to a marked reduction of restenosis, which is a major limitation of percutaneous coronary intervention for coronary artery disease. The next-generation Xience V? (Abbott Vascular, CA, USA) everolimus-eluting stent was designed to address the limitations of first-generation drug-eluting stents. The cobalt-chromium stent platform with an open-cell design offers excellent deliverability. Moreover, the combination of a thin fluoropolymer eluting the antirestenotic drug everolimus provides both an effective suppression of neointimal tissue and rapid re-endothelialization above and between stent struts in preclinical studies. Large randomized clinical trials comparing the everolimus-eluting stent with the Taxus Express? and Liberté? (Boston Scientific, MA, USA) paclitaxel-eluting stents have shown reduced rates of repeat revascularization, myocardial infarction and stent thrombosis at 1-year follow-up with the everolimus-eluting stent. However, we will have to await long-term (5-year) data from these randomized clinical trials with the everolimus-eluting stent to determine whether the observed benefit is robust. Furthermore, data are currently limited the clinical performance of the everolimus-eluting stent relative to drug-eluting stents other than the Taxus Express and Liberté paclitaxel-eluting stents, although a large number of trials are now being conducted to address these questions. In this article, we provide a comprehensive overview of (pre)clinical studies with the everolimus-eluting stent. 相似文献
987.
Human dental pulp stem cells expressing STRO‐1, c‐kit and CD34 markers in peripheral nerve regeneration 下载免费PDF全文
Gianluca Carnevale Alessandra Pisciotta Massimo Riccio Laura Bertoni Sara De Biasi Lara Gibellini Alessio Zordani Gian Maria Cavallini Giovanni Battista La Sala Giacomo Bruzzesi Adriano Ferrari Andrea Cossarizza Anto de Pol 《Journal of tissue engineering and regenerative medicine》2018,12(2):e774-e785
Peripheral nerve injuries are a commonly encountered clinical problem and often result in long‐term functional defects. The application of stem cells able to differentiate in Schwann cell‐like cells in vitro and in vivo, could represent an attractive therapeutic approach for the treatment of nerve injuries. Further, stem cells sources sharing the same embryological origin as Schwann cells might be considered a suitable tool. The aim of this study was to demonstrate the ability of a neuroectodermal subpopulation of human STRO‐1+/c‐Kit+/CD34+ DPSCs, expressing P75NTR, nestin and SOX‐10, to differentiate into Schwann cell‐like cells in vitro and to promote axonal regeneration in vivo, which led to functional recovery as measured by sustained gait improvement, in animal rat model of peripheral nerve injury. Transplanted human dental pulp stem cells (hDPSCs) engrafted into sciatic nerve defect, as revealed by the positive staining against human nuclei, showed the expression of typical Schwann cells markers, S100b and, noteworthy, a significant number of myelinated axons was detected. Moreover, hDPSCs promoted axonal regeneration from proximal to distal stumps 1 month after transplantation. This study demonstrates that STRO‐1+/c‐Kit+/CD34+ hDPSCs, associated with neural crest derivation, represent a promising source of stem cells for the treatment of demyelinating disorders and might provide a valid alternative tool for future clinical applications to achieve functional recovery after injury or peripheral neuropathies besides minimizing ethical issues. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
988.
Pharmacokinetics and safety of intravenous voriconazole in children after single- or multiple-dose administration 下载免费PDF全文
Walsh TJ Karlsson MO Driscoll T Arguedas AG Adamson P Saez-Llorens X Vora AJ Arrieta AC Blumer J Lutsar I Milligan P Wood N 《Antimicrobial agents and chemotherapy》2004,48(6):2166-2172
We conducted a multicenter study of the safety, tolerability, and plasma pharmacokinetics of the parenteral formulation of voriconazole in immunocompromised pediatric patients (2 to 11 years old). Single doses of 3 or 4 mg/kg of body weight were administered to six and five children, respectively. In the multiple-dose study, 28 patients received loading doses of 6 mg/kg every 12 h on day 1, followed by 3 mg/kg every 12 h on day 2 to day 4 and 4 mg/kg every 12 h on day 4 to day 8. Standard population pharmacokinetic approaches and generalized additive modeling were used to construct the structural pharmacokinetic and covariate models used in this analysis. In contrast to that in adult healthy volunteers, elimination of voriconazole was linear in children following doses of 3 and 4 mg/kg every 12 h. Body weight was more influential than age in accounting for the observed variability in voriconazole pharmacokinetics. Elimination capacity correlated with the CYP2C19 genotype. Exposures were similar at 4 mg/kg every 12 h in children (median area under the concentration-time curve (AUC), 14,227 ng. h/ml) and 3 mg/kg in adults (median AUC, 13,855 ng. h/ml). Visual disturbances occurred in 5 (12.8%) of the 39 patients and were the only drug-related adverse events that occurred more than once. No withdrawals from the study were related to voriconazole. We conclude that pediatric patients have a higher capacity for elimination of voriconazole per kilogram of body weight than do adult healthy volunteers and that dosages of 4 mg/kg may be required in children to achieve exposures consistent with those in adults following dosages of 3 mg/kg. 相似文献
989.
de Moura Almeida A Cotrim HP Barbosa DB de Athayde LG Santos AS Bitencourt AG de Freitas LA Rios A Alves E 《World journal of gastroenterology : WJG》2008,14(9):1415-1418
AIM:To evaluate the sensitivity and specificity of abdominal ultrasound (US) for the diagnosis of hepatic steatosis in severe obese subjects and its relation to histological grade of steatosis. METHODS: A consecutive series of obese patients, who underwent bariatric surgery from October 2004 to May 2005, was selected. Ultrasonography was performed in all patients as part of routine preoperative time and an intraoperative wedge biopsy was obtained at the beginning of the bariatric surgery. The US and histological findings of steatosis were compared, considering histology as the gold standard. RESULTS: The study included 105 patients. The mean age was 37.2 ± 10.6 years and 75.2% were female. The histological prevalence of steatosis was 89.5%. The sensitivity and specificity of US in the diagnosis of hepatic steatosis were, respectively, 64.9% (95% CI: 54.9-74.3) and 90.9% (95% CI: 57.1-99.5). The positive predictive value and negative predictive value were, respectively, 98.4% (95% CI: 90.2-99.9) and 23.3% (95% CI: 12.3-39.0). The presence of steatosis onUS was associated to advanced grades of steatosis on histology (P = 0.016). CONCLUSION: Preoperative abdominal US in our series has not shown to be an accurate method for the diagnosis of hepatic steatosis in severe obese patients. Until another non-invasive method demonstrates better sensitivity and specificity values, histological evaluation may be recommended to these patients undergoing bariatric surgery. 相似文献
990.
Tonelli AR Khalife WT Cao M Young VB 《The American journal of the medical sciences》2008,335(6):504-506
Coccidioidomycosis is endemic in the southwestern United States, resulting in 100,000 infections annually. The majority of these infections are asymptomatic or manifest as community-acquired pneumonia. In rare cases, patients can present with a mononuclear-cell predominant pyopneumothorax. The presence of spherules in tissue specimens is pathognomonic of this condition. A 72-year-old man born in Arizona with a heavy smoking history, presented with a 1-month history of weakness, night sweats, exertional dyspnea, and left pleuritic chest pain. The physical examination was remarkable for decreased breath sounds and dullness to percussion at the left lung base. His initial laboratory examination showed leukocytosis, eosinophilia, and elevated C-reactive protein. Computed tomography of the chest revealed a left lower lobe infiltrate, a cavity with air-crescent sign and hydropneumothorax. The pleural fluid was sampled and revealed an eosinophilic exudate with normal pH. Bacterial and fungal cultures of the pleural fluid were negative. Biopsy of the cavity wall showed chronic inflammation, fungal hyphae, and rare spherule-like structures. The surgical specimen culture grew Coccidioides immitis. Complement fixation for coccidioidomycosis performed on a serum sample was positive at a titer of 1:2 but a latex agglutinin test was negative. The patient was diagnosed with chronic fibrocavitary pneumonia with pyopneumothorax secondary to C. immitis infection and discharged on itraconazole for 1 year. Coccidioidomycosis can present in a variety of forms and should be part of the differential diagnosis in patients presenting with cavitation, air-crescent sign, eosinophilic pleural effusion, and hyphae and spherules on the tissue specimen. Chronic fibrocavitary pneumonia should be especially considered in patients who lived in endemic areas and have risk factors such as diabetes mellitus or pulmonary fibrosis related to smoking. 相似文献