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71.
Tai TF Chiang CP Lin CP Lin CC Jeng JH 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(6):e55-e60
The cementodentinal tear is rarely detected by noninvasive procedures owing to its clinical picture simulating a root fracture or a periodontal or endodontic lesion. We present a case of complex cementodentinal tears in a 79-year-old woman who presented a repeated swelling at the labial mucosa of the left maxillary central incisor for 6 months. Periapical radiographs demonstrated a vertical radiolucent fracture line extending from the root apex along the mesial aspect of the root to near the middle portion of the root of the left maxillary central incisor. Because endodontic re-treatment failed to cure the disease, periapical surgery was performed, and 2 fractured U-shaped root fragments around the apical root surface were removed. Histologic examination showed that the 2 fractured root fragments were composed mainly of the dentin covered by a thin layer of the cementum and overlying periodontal ligament tissue, suggesting cementodentinal tears. A swelling recurred 8 months after the initial operation. Therefore, a second periapical surgery was performed. Although no obvious fracture line was observed around the root surface, the second surgery did not cure the disease, either. A persistent small swelling was noted at the alveolar mucosa of the affected tooth during the follow-up. We conclude that although a cementodentinal tear can be detected by a careful radiographic examination, its clinical outcome is not predictable by surgical removal only. 相似文献
72.
Cappellini MD Bejaoui M Agaoglu L Porter J Coates T Jeng M Lai ME Mangiagli A Strauss G Girot R Watman N Ferster A Loggetto S Abish S Cario H Zoumbos N Vichinsky E Opitz H Ressayre-Djaffer C Abetz L Rofail D Baladi JF 《Clinical therapeutics》2007,29(5):909-917
BACKGROUND: Iron chelation therapy (ICT) with deferoxamine (DFO), the current standard for the treatment of iron overload in patients with transfusion-dependent disorders such as beta-thalassemia, requires regular subcutaneous or intravenous infusions. This can lead to reduced quality of life and poor adherence, resulting in increased morbidity and mortality in iron-overloaded patients with beta-thalassemia. Deferasirox is an orally administered iron chelator that has been approved for use in the United States, Switzerland, and other countries. OBJECTIVE: This analysis was conducted to compare patient-reported outcomes (PROs) during receipt of DFO infusions or once-daily oral therapy with deferasirox (ICL670). METHODS: PROs were prospectively evaluated as part of a randomized, Phase III study comparing the efficacy and safety profile of DFO 20 to 60 mg/kg per day with those of deferasirox 5 to 30 mg/kg per day in patients (age > or =2 years) with beta-thalassemia who were receiving regular transfusions and had a liver iron concentration of > or =2 mg/g dry weight. PRO questionnaires were completed by patients or a parent or legal guardian at baseline, week 4, week 24, and end of study (EOS). Patients assessed their level of satisfaction with study treatment (very satisfied, satisfied, neutral, dissatisfied, or very dissatisfied) and rated its convenience (very convenient, convenient, neutral, inconvenient, or very inconvenient). Time lost from normal activities due to ICT in the previous 4 weeks was recorded using a single global assessment. At week 4, patients who had previous experience with DFO were asked to indicate their preference for treatment (ICT received before the study, ICT received during the study, no preference, or no response) and the reason for that preference. At EOS, all patients were asked if they would be willing to continue using the ICT they had received during the study. All study analyses were performed in all patients who received at least 1 dose of study medication. RESULTS: Five hundred eighty-six patients (304 females, 282 males; age range, 2-53 years) received treatment with DFO (n = 290) or deferasirox (n = 296). Significantly more patients treated with deferasirox reported being very satisfied or satisfied with treatment compared with those treated with DFO (week 4: 92.0% vs 50.4%, respectively; week 24: 89.6% vs 44.0%; EOS: 85.1% vs 38.7%; all, P < 0.001). At the same time points, the majority of those treated with deferasirox reported that treatment was very convenient or convenient compared with those treated with DFO (95.5% vs 21.3%, 91.7% vs 17.4%, and 92.7% vs 11.3%, respectively; all, P < 0.001). Among patients who had previously taken DFO and were randomized to receive deferasirox during the study, 96.9% reported a preference for deferasirox over DFO. At EOS, the proportion of patients indicating a willingness to continue study therapy was significantly greater in those receiving deferasirox than in those receiving DFO (85.8% vs 13.8%; P < 0.001). CONCLUSIONS: In this study, patient-reported satisfaction and convenience were significantly higher for the once-daily, oral ICT deferasirox than for DFO infusions. Among patients who had received DFO before the study, the majority indicated a preference for deferasirox over DFO. Most patients receiving deferasirox indicated that they would be willing to continue taking it. These results suggest that deferasirox had a positive impact on patients' daily lives. 相似文献
73.
Elissa R. Engel Adrienne Hammill Denise Adams Roderic J. Phillips Michael Jeng Megha M. Tollefson Ionela Iacobas Deborah Schiff Shoshana Greenberger Michael Kelly Ilona Frieden Nibal Zaghloul Beth Drolet Amy Geddis Dov Goldenberg Kiersten Ricci 《Pediatric blood & cancer》2023,70(4):e30215
Background
Capillary lymphatic venous malformations (CLVM) and associated syndromes, including Klippel–Trenaunay syndrome (KTS) and congenital lipomatous overgrowth, vascular malformation, epidermal nevi, skeletal, and spinal syndrome (CLOVES), are underrecognized disorders associated with high morbidity from chronic pain, recurrent infections, bleeding, and clotting complications. The rarity of these disorders and heterogeneity of clinical presentations make large-scale randomized clinical drug trials challenging. Identification of PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha [gene]) mutations in CLVM has made targeted medications, such as sirolimus, attractive treatment options. The aim of this study was to investigate the safety and efficacy of sirolimus therapy in CLVM.Procedure
A combined prospective and retrospective cohort of pediatric and young adult patients with CLVM treated with sirolimus was evaluated for disease response, including symptom improvement, quality of life (QOL), and radiologic response. Sirolimus dosing regimens and toxicities were also assessed.Results
Twenty-nine patients with CLVM, including KTS and CLOVES, were included. Ninety-three percent of patients reported improved QOL, and 86% had improvement in at least one symptom. Most significantly, improvement was noted in 100% of patients with bleeding and 89% with thrombotic complications with corresponding decreases in mean D-dimer (p = .008) and increases in mean fibrinogen (p = .016). No patients had progressive disease on sirolimus. Most common side effects included neutropenia, lymphopenia, infection, and aphthous ulcers/stomatitis. No toxicities were life-threatening, and none required long-term discontinuation of sirolimus.Conclusion
Sirolimus appears to be effective at reducing complications and improving QOL in patients with CLVM and associated syndromes. In this patient cohort, sirolimus was well tolerated and resulted in few treatment-related toxicities. 相似文献74.
BACKGROUND AND PURPOSE: The goal of this study was to examine the reliability and validity of measurements obtained with the Alberta Infant Motor Scale (AIMS) for evaluation of preterm infants in Taiwan. SUBJECTS: Two independent groups of preterm infants were used to investigate the reliability (n=45) and validity (n=41) for the AIMS. METHODS: In the reliability study, the AIMS was administered to the infants by a physical therapist, and infant performance was videotaped. The performance was then rescored by the same therapist and by 2 other therapists to examine the intrarater and interrater reliability. In the validity study, the AIMS and the Bayley Motor Scale were administered to the infants at 6 and 12 months of age to examine criterion-related validity. RESULTS: Intraclass correlation coefficients (ICCs) for intrarater and interrater reliability of measurements obtained with the AIMS were high (ICC=.97-.99). The AIMS scores correlated with the Bayley Motor Scale scores at 6 and 12 months (r=.78 and.90), although the AIMS scores at 6 months were only moderately predictive of the motor function at 12 months (r=.56). CONCLUSION AND DISCUSSION: The results suggest that measurements obtained with the AIMS have acceptable reliability and concurrent validity but limited predictive value for evaluating preterm Taiwanese infants. 相似文献
75.
Background
Intrahepatic segmental portal vein thrombosis after living-related liver transplantation (LRLT) is uncommon. The cause remains unclear.Methods
After providing written informed consent, 25 recipients receiving LRLT at our institution from January 2011 to September 2013 were enrolled in this study. We performed triphase computerized tomographic (CT) study of the liver graft of each recipient 1 month after LRLT. The patencies of hepatic artery, portal vein, and hepatic vein were evaluated in detail. The triphase CT scans of the liver of each donor before transplantation also were reviewed. Thrombosis of the intrahepatic segmental portal vein was defined as the occlusion site of the portal vein being intrahepatic. Extrahepatic portal vein thrombosis was excluded in this study.Results
Among the 25 patients, 2 (8%) developed thrombosis of intrahepatic segmental portal vein. One 47-year-old man received LRLT for hepatitis B viral infection–related liver cirrhosis (Child-Pugh class C) with 3 hepatocellular carcinomas (total tumor volume <8 cm). Another 53-year-old man received LRLT for alcoholic liver cirrhosis (Child-Pugh class C). Both had developed progressive jaundice and cholangitis 1 month after surgery. Intrahepatic biliary stricture was found on the follow-up magnetic resonance images. However, liver triphase CT study demonstrated occlusion of intrahepatic portal vein of segment 8 in each patient. Radiologic interventions and balloon dilatation therapy via percutaneous transhepatic biliary drainage route improved the symptoms and signs of cholangitis and obstructive jaundice for both.Conclusions
Thrombosis of intrahepatic segmental portal vein is not common but is usually associated with complications of intrahepatic bile duct. Early detection is important, and follow-up CT study of liver is suggested. 相似文献76.
Background
Despite recent advances in preoperative diagnostic imaging and operative techniques, biliary variation of the donor still remains a challenge in the procurement of graft. The supraportal right bile duct (BD) variant including presentation as trifurcation is a potential trap for injuring the remnant bile duct of donor.Methods
Before living/related-donor liver transplantation (LRLT), cholangiogram with magnetic resonance images of each donor was performed as a routine. After exploration of the donor before hilar dissection, intraoperative chloangiography (IOC) was routinely performed. Among the supraportal right bile duct variants, if the preoperative cholangiography showed a suspected trifurcation of the bile duct, we then performed 3 sessions of IOC during liver graft procurement, including prior to hilar dissection, before the division of bile ducts and after the division. We reviewed the cholangiogram and the postoperative laboratory data of a consecutive series of 25 donors of LRLT.Results
There was no division injury of the remnant bile duct of all of the donors.Conclusions
Repeated IOC is suggested as a routine for variants of supraportal right bile ducts especially trifurcation pattern in graft procurement to avoid the injury of donor remnant bile ducts. 相似文献77.
Hepatocellular carcinoma (HCC) is one of the most frequent and fatal human cancers worldwide and its development and prognosis are intimately associated with chronic infection with hepatitis B virus (HBV). The identification of genetic mutations and molecular mechanisms that mediate HBV-induced tumorigenesis therefore holds promise for the development of potential biomarkers and targets for HCC prevention and therapy. The presence of HBV pre-S gene deletions in the blood and the expression of pre-S deleted proteins in the liver tissues of patients with chronic hepatitis B and HBV-related HCC have emerged as valuable biomarkers for higher incidence rates of HCC development and a higher risk of HCC recurrence after curative surgical resection, respectively. Moreover, pre-S deleted proteins are regarded as important oncoproteins that activate multiple signaling pathways to induce DNA damage and promote growth and proliferation in hepatocytes, leading to HCC development. The signaling molecules dysregulated by pre-S deleted proteins have also been validated as potential targets for the prevention of HCC development. In this review, we summarize the clinical and molecular implications of HBV pre-S gene deletions and pre-S deleted proteins in HCC development and recurrence and highlight their potential applications in HCC prevention and therapy. 相似文献
78.
Search for relationships among the hemolytic, phospholipolytic, and neurotoxic activities of snake venoms
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T.-W. Jeng R. A. Hendon H. Fraenkel-Conrat 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(2):600-604
Several snake venom neurotoxins are larger and more complex than the well-studied group of postsynaptic toxins exemplified by alpha-bungarotoxin. Several of these, exemplified by beta-bungarotoxin, show phospholipase A2 activity (phosphatide 2-acylhydrolase, EC 3.1.1.4) when tested in the presence of detergents. The high hemolytic activity of crotoxin, the neurotoxin of Crotalus durissus terrificus, in the presence of lecithin has been attributed to this activity. The phospholipase A2 activity of several snake venom proteins has now been compared under the physiological conditions of the hemolysis tests.It appears that only the basic component of crotoxin, B, is enzymatically active, and that its activity is not inhibited by component A under these conditions, or in the presence of deoxycholate. Phosphatidylserine is found to be digested more readily than egg white phosphatidylcholine; and also causes hemolysis in conjunction with much lower levels of crotoxin. In neither case is calcium required or stimulating.Phospholipase from Crotalus adamanteus, which is not neurotoxic, digests phosphatidylcholine more rapidly than does crotoxin, but phosphatidylserine more slowly; yet it is slightly less active than crotoxin in the hemolysis test with phosphatidylcholine, and much less with phosphatidylserine. The digestion of several phospholipids by either enzyme fails to release the expected protons in the absence of detergents at 37 degrees .beta-Bungarotoxin, highly neurotoxic, has negligible phospholipase A2 activity in the absence of detergents, and is almost nonhemolytic in conjunction with all phospholipids tested.Binding studies with (125)I-labeled compounds show that rabbit erythrocytes and ghosts have much greater affinity for crotoxin than for beta-bungarotoxin and do not bind Crotalus adamanteus phospholipase. The crotoxin complex is split in the course of binding, with only component B, the hemolytic component, becoming bound. It appears that the role of component A may be to diminish the nonspecific binding tendency of component B.Our data appear to be consistent with the concepts that affinity to membranes, particularly to specific sites on synaptic membranes, is the critical requirement for beta type neurotoxicity, and that this property, at least in some instances, has evolved from phospholipase A2 enzymes, but does not necessarily require retention and expression of enzymatic activity. 相似文献
79.
Glucagon-like peptide 1 (GLP-1) is a potent insulinotropic hormone currently under study as a therapeutic agent for type 2 diabetes. Since an understanding of the molecular mechanisms leading to high-affinity receptor (R) binding and activation may facilitate the development of more potent GLP-1R agonists, we have localized specific regions of GLP-1R required for binding. The purified N-terminal fragment (hereafter referred to as NT) of the GLP-1R produced in either insect (Sf9) or mammalian (COS-7) cells was shown to bind GLP-1. The physical interaction of NT with GLP-1 was first demonstrated by cross-linking ((125)I-GLP-1/NT complex band at approximately 28 kDa) and secondly by attachment to Ni(2+)-NTA beads. The GLP-1R NT protein attached to beads bound GLP-1, but with lower affinity (inhibitory concentration (IC(50)): 4.5 x 10(-7) M) than wild-type (WT) GLP-1R (IC(50): 5.2 x 10(-9)M). The low affinity of GLP-1R NT suggested that other receptor domains may contribute to GLP-1 binding. This was supported by studies using chimeric glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 receptors. GIP(1-151)/GLP-1R, but not GIP(1-222)/GLP-1R, exhibited specific GLP-1 binding and GLP-1-induced cAMP production, suggesting that the region encompassing transmembrane (TM) domain 1 through to TM3 was required for binding. Since it was hypothesized that certain charged or polar amino acids in this region might be involved in binding, these residues (TM2-TM3) were analyzed by substitution mutagenesis. Five mutants (K197A, D198A, K202A, D215A, R227A) displayed remarkably reduced binding affinity. These studies indicate that the NT domain of the GLP-1R is able to bind GLP-1, but charged residues concentrated at the distal TM2/extracellular loop-1 (EC1) interface (K197, D198, K202) and in EC1 (D215 and R227) probably contribute to the binding determinants of the GLP-1R. 相似文献
80.
Massive pulmonary embolism is an uncommon complication of multiple myeloma treated with thalidomide-dexamethasone regimen. In 2006, multiple myeloma was diagnosed in a 72-year-old man, who received thalidomide-dexamethasone therapy. In January 2007, echocardiography and computerized tomography identified massive pulmonary embolism in the pulmonary arteries and a deep vein thrombus of the right leg. The patient also had an elevated concentration of B-type natriuretic peptide. After heparinization and warfarin therapy, the patient's condition improved. This is the first report of a patient with a rare complication of pulmonary embolism from thalidomide-treated multiple myeloma. 相似文献