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41.
Summary Insulin autoantibodies, like islet cell antibodies, are found not only in the sera of newly diagnosed Type 1 (insulin-dependent) diabetic patients and their relatives, but also in patients with other autoimmunities who do not develop diabetes. Insulin autoantibodies are oligo/monoclonal and frequently binding-site restricted. As determinant selection is genetically determined, we questioned whether certain polymorphisms of insulin autoantibodies, identified by their binding site on the insulin molecule, could better discriminate for Type 1 diabetes, which is also HLA determined. First, we raised monoclonal antibodies to human insulin by classic fusion methods in order to determine the range of antibody polymorphism, and identified five distinct types by their binding profiles to a panel of insulin variants, using an enzyme-linked immunosorbent assay. Two of these polymorphisms, type A and type B, were subsequently found in insulin autoantibody positive human sera using the same panel of insulin variants, and successfully distinguished diabetes-related from diabetes-unrelated individuals. Thus, the type B polymorphism was responsible for binding in 60% of 41 insulin autoantibody positive individuals with polyautoimmune disease but no personal or family history of diabetes (diabetes unrelated), but in only 2% of a group which comprised 17 newly-diagnosed insulin autoantibody positive Type 1 diabetic patients, 19 insulin autoantibody positive discordant twins of Type 1 diabetes and six insulin autoantibody positive healthy siblings of Type 1 diabetic patients (diabetes related) (p<0.01). Isolation of the type A polymorphism alone reduced the proportion of false negatives in the insulin autoantibody test for diabetes relatedness from 49% to 20% without diminishing its specificity. Thus, insulin autoantibody polymorphisms are more discriminating than the nominal antibody, due possibly to linkage between immune response genes determining response to the type A epitope on the one hand, and susceptibility to Type 1 diabetes on the other. 相似文献
42.
Tayyaba?AfsarEmail author Muhammad?Rashid?Khan Suhail?Razak Shafi?Ullah Bushra?Mirza 《BMC complementary and alternative medicine》2015,15(1):136
Background
Inflammation and pain underlies several pathological conditions. Synthetic drugs used for the management of these conditions carry severe toxic effects. Globally efforts are ongoing to introduce novel medicinal plants to develop effective, economic and innocuous drugs. The current study was aimed at investigating the antipyretic, anti-inflammatory and analgesic activity of methanol extract of A. hydaspica aerial parts (AHM) and its active fraction. Furthermore identification and isolation of polyphenolic compounds was carried out to identify the active principles.Methods
Yeast induced pyrexia, Paw edema, acetic acid-induced writhing and hot plate test were carried out in vivo. HPLC-DAD analysis and combination of different chromatographic techniques, involving vacuum liquid chromatography (VLC) and flash chromatography (FC) were carried out for chemical characterization. The structural heterogeneity of flavanols was characterized by ESI- MS, 1H NMR, 13C NMR and 2D NMR spectroscopic analyses, and also by comparison with reported literature.Results
Oral administration of A. hydaspica methanol extract (AHM) and A. hydaspica ethyl acetate fraction (AHE), showed dose and time dependent decrease in body temperature in yeast induced pyrexia, comparable to standard, Paracetamol. AHM and AHE (150 mg/kg) significantly (p?<?0.001) inhibit pain sensation in various pain models, i.e. acetic acid induced writhing and hot plate test. Similarly AHM and AHE demonstrated an anti-inflammatory effect in carrageenan-induced paw edema in rats and 150 mg/kg dose being distinctly more effective (91.92% inhibition). When studied on prostaglandin E2 (PGE2) induced edema in rats, AHM and AHE showed maximum inhibition of edema at 150 mg/kg after 4 h. HPLC chromatogram of AHM revealed the presence of gallic acid, catechin, rutin and caffeic acid. Chromatographic separation and structure characterization of AHE, has led to the identification of three flavan-3-ol derivative including 7-O-galloyl catechin, +catechin and methyl gallate, which have been reported for the first time in A. hydaspica.Conclusion
These results revealed that the presence of bioactive compounds in A. hydaspica might be responsible for the pharmacological activities, confirming the indigenous utility of A. hydaspica against inflammatory disorders.43.
Narendra Battula Dimitrios Tsapralis David Mayer John Isaac Paolo Muiesan Robert P Sutcliffe Simon Bramhall Darius Mirza Ravi Marudanayagam 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(2):157-163
Objectives: Isolated intrahepatic recurrence is noted in up to 40% of patients following curative liver resection for colorectal liver metastases (CLM). The aims of this study were to analyse the outcomes of repeat hepatectomy for recurrent CLM and to identify factors predicting survival.Methods: Data for all liver resections for CLM carried out at one centre between 1998 and 2011 were analysed.Results: A total of 1027 liver resections were performed for CLM. Of these, 58 were repeat liver resections performed in 53 patients. Median time intervals were 10.5 months between the primary resection and first hepatectomy, and 15.4 months between the first and repeat hepatectomies. The median tumour size was 3.0 cm and the median number of tumours was one. Six patients had a positive margin (R1) resection following first hepatectomy. There were no perioperative deaths. Significant complications included transient liver dysfunction in one and bile leak in two patients. Rates of 1-, 3-and 5-year overall survival following repeat liver resection were 85%, 61% and 52%, respectively, at a median follow-up of 23 months. R1 resection at first hepatectomy (P = 0.002), a shorter time interval between the first and second hepatectomies (P = 0.02) and the presence of extrahepatic disease (P = 0.02) were associated with significantly worse overall survival.Conclusions: Repeat resection of CLM is safe and can achieve longterm survival in carefully selected patients. A preoperative knowledge of poor prognostic factors helps to facilitate better patient selection. 相似文献
44.
Keith J Roberts Georgina Blanco Jonathan Webber Ravi Marudanayagam Robert P Sutcliffe Paolo Muiesan Simon R Bramhall John Isaac Darius F Mirza 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(9):814-821
Objectives
Total pancreatectomy (TP) is associated with significant morbidity and mortality. The severity of postoperative diabetes and existence of ‘brittle diabetes’ are unclear. This study sought to identify quality of life (QoL) and diabetes-specific outcomes after TP.Methods
Patients who underwent TP were matched for age, sex and duration of diabetes with patients with type 1 diabetes. General QoL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) core quality of life questionnaire QLQ-C30 and the PAN26 tool. Diabetes-specific outcomes were assessed using the Problem Areas in Diabetes (PAID) tool and an assessment of diabetes-specific complications and outcomes.Results
A total of 123 patients underwent TP; 88 died (none of diabetic complications) and two were lost to follow-up. Of the remaining 33 patients, 28 returned questionnaires. Fourteen general and pancreas-specific QoL measurements were all significantly worse amongst the TP cohort (QLQ-C30 + PAN26). However, when diabetes-specific outcomes were compared using the PAID tool, only one of 20 was significantly worse. HbA1c values were comparable (P = 0.299), as were diabetes-related complications such as hypoglycaemic attacks and organ dysfunction.Conclusions
Total pancreatectomy is associated with impaired QoL on general measures compared with that in type 1 diabetes patients. Importantly, however, there was almost no significant difference in diabetes-specific outcomes as assessed by a diabetes-specific questionnaire, or in diabetes control. This study does not support the existence of ‘brittle diabetes’ after TP. 相似文献45.
Ulises Rodriguez-Prado Diego Emiliano Jimenez-Gonzalez Guillermina Avila Armando E. Gonzalez Williams Arony Martinez-Flores Carmen Mondragon de la Pe?a Rigoberto Hernandez-Castro Mirza Romero-Valdovinos Ana Flisser Fernando Martinez-Hernandez Pablo Maravilla Jose Juan Martinez-Maya 《The American journal of tropical medicine and hygiene》2014,91(6):1149-1153
We evaluated the genetic variation of Echinococcus G7 strain in larval and adult stages using a fragment of the mitochondrial cox1 gen. Viscera of pigs, bovines, and sheep and fecal samples of dogs were inspected for cystic and canine echinococcosis, respectively; only pigs had hydatid cysts. Bayesian inferences grouped the sequences in an E. canadensis G7 cluster, suggesting that, in Mexico, this strain might be mainly present. Additionally, the population genetic and network analysis showed that E. canadensis in Mexico is very diverse and has probably been introduced several times from different sources. Finally, a scarce genetic differentiation between G6 (camel strain) and G7 (pig strain) populations was identified.Echinococcus granulosus sensu lato (s.l.) includes species that cause cystic echinococcosis (CE), one of the most important and widespread parasitic zoonoses. Recent phylogenetic studies based on both mitochondrial and nuclear DNA genes show that E. granulosus s.l. consists of at least four valid species: E. granulosus sensu stricto (s.s.; genotypes G1–G3), E. equinus (G4), E. ortleppi (G5), and E. canadensis (G6–G10). Genotypes G6/G7 are closely related and referred to as camel and pig strains, respectively.1–3 The pig–dog cycle is mainly present in Mexico and maintains the G7 strain.4,5 Although there are isolated reports of E. oligarthrus in a wild cat,6
E. ortleppi (E. granulosus s.l.; G5) in a patient,7 and E. granulosus s.s. (G1) in a rural pig, there is no evidence that these species are maintained in Mexico.8 No data of CE caused by G7 have been documented in Mexican patients, although there is a high number of E. canadensis G7-infected patients in central Europe, pointing to the importance of this strain as a cause of human CE.9,10 There are only two genetic studies performed in samples from Mexico. Cruz-Reyes and others5 documented that G7 parasites of Mexican and Polish pig isolates showed similar patterns by restriction fragment length polymorphism (RFLP) of ribosomal DNA (rDNA) internal transcribed spacer 1 (ITS1) and random amplified polymorphic DNA (RAPD) techniques, and although polymerase chain reaction (PCR) -sequencing analysis of mitochondrial cox1 gen fragment was performed, no polymorphism data were reported. Sharma and others11 identified two variants (A and B) inside of the G6/G7 group consisting of samples from Mexico and Argentina using five nuclear markers (elongation factor 1α, transforming growth factor-β receptor kinase, thioredoxin peroxidase, calreticulin, and ezrin-radixin-moesin-like protein). Because some local slaughter records from northern Mexico indicate the presence of Echinococcus spp. in livestock animals,5 the objective of this study was to investigate if parasites in pigs and dogs correspond to G7 and if so, describe its genetic variation.Infected animals were identified in the municipal slaughterhouse of Calera, Zacatecas (north central Mexico), where farm and backyard livestock animals coming from the whole state and other surrounding states were included. For this purpose, viscera from 387 pigs, 243 bovines, and 32 sheep were inspected for the larval stage of Echinococcus. Nine pigs (six pigs from Zacatecas, two pigs from Aguascalientes, and one pig from Morelos) were found infected, and hydatid cysts were obtained under aseptic conditions. After cyst contents were aspirated and centrifuged, aliquots were examined under microscopy to confirm the presence of protoscolices, and pellets were kept in 70% ethanol at −20°C until DNA extraction. Each cyst from each animal was considered as an isolate.Based on the presence of the parasites previously identified in Calera''s slaughterhouse, a rural community located in the central area of Zacatecas at 22°55′ N, 102°48′ W was selected to look for the adult stage of this parasite. For this search, all dogs (60) present in the community were sampled one time for feces after obtaining verbal consent from the owner; samples were used to identify taeniid eggs by the Faust technique, antigens in stool samples (copro-antigens) by enzyme-linked immunosorbent assay (ELISA; CpAg ELISA), and DNA by Copro-PCR. The CpAg ELISA was performed as described by Allan and others12 and Moro and others.13 For Copro-PCR, only positive samples by CpAg ELISA were analyzed using JB3 and JB4 primers to amplify a cox1 gen fragment.14 Coprological analysis of dogs showed that 11 samples were positive by CpAg ELISA (18.3%); only 2 of these samples had taeniid tapeworms (3.4%), and 3 of 11 samples yielded products of approximately 450 bp. All amplicons obtained of hydatid cysts and fecal samples were purified, sequenced on both strands, submitted to GenBank (accession numbers ), and compared with several mitochondrial DNA sequences of cox1. Dogs positive for taeniid eggs or antigens were purged and treated with praziquantel at 30 mg/kg and arecoline bromide at 2 mg/kg. The protocol was previously approved by the Ethics and Research Committees of the General Hospital “Dr. Manuel Gea Gonzalez”; government and health authorities of the municipality and community also authorized our study.All sequences were subjected to the Basic Local Alignment Search Tool (BLAST) search in the GenBank database; multiple alignments were performed with the CLUSTAL W and MUSCLE programs, KF734649-KF73466015,16 with manual adjusted in MEGA program v517 to determine the appropriate model of molecular evolution in the Modeltest 3.7 program.18 The phylogenetic reconstruction using Bayesian inference was performed with Mr Bayes 3.2.1 program.19 Unrooted haplotype networks were created using NETWORK 4.611 software and nested according to the rules in median-joining networks.20 An analysis of genetic diversity within and between populations was performed using DnaSPv421 and included nucleotide diversity (π), haplotype polymorphism (θ), genetic differentiation index (FST), and Tajima''s D test. Analysis of molecular variance (AMOVA) was used to examine the population genetic structure between populations by ΦST as the genetic fixation index (analogous to FST) obtained by ARLEQUIN software.22After multiple alignments, all sequences of larval and adult stages showed 98% or higher identity with E. canadensis, whereas the Bayesian phylogenetic tree and the haplotype network inference grouped these sequences in the E. canadensis G7 cluster. Sequences for cox1 of E. canadensis from Africa, Asia, Europe, Latin America, and North America deposited in the GenBank databases (N = 58) as well as our sequences (accession numbers ) were analyzed. The results for π and θ were 0.0118 and 0.718, and the result of Tajima''s D test was −2.1885 (P < 0.01). Genetic differentiation indexes between different paired sequences of E. canadensis genotypes are shown in KF734649-KF734660Population A Population B FST AMOVA References ΦST SS VC Percent G6 G7 0.031 0.085 1.640 0.060 8.5 30–38 G6 G8 0.893 0.937 37.767 5.395 93.7 G6 G10 0.624 0.613 15.798 0.726 61.3 G7 G8 0.783 0.760 27.250 4.315 76.0 30,31,39,40 G7 G10 0.359 0.336 8.722 0.532 33.6 G8 G10 0.882 0.881 40.025 5.991 88.1 30,34,36,39 Mexico (G7) Europe (G7) 0.201 0.179 3.494 0.259 17.9 30,31,40,41 Latin America (G7) Europe (G7) 0.146 0.113 2.461 0.138 11.3 Latin America (G7) Africa (G6) 0.147 0.154 3.334 0.171 15.4 31,33,35 Latin America (G7) Asia (G6) 0.156 0.126 2.722 0.144 12.6 30,31 Latin America (G7) Africa–Asia (G6) 0.151 0.205 3.833 0.180 20.6 30,31,33,35 Europe (G7) Africa (G6) 0.047 0.043 0.727 0.022 4.3 30,33,35,40,41 Europe (G7) Asia (G6) 0.061 0.019 0.472 0.024 9.1 30,40,41 Europe (G7) Africa-Asia (G6) 0.042 0.060 0.650 0.233 6.0 30,33,35,40,41