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31.
Identification of a Thymidylate Synthase Gene within the Genome of Chilo Iridescent Virus 总被引:1,自引:0,他引:1
The thymidylate synthase (TS, EC 2.1.1.45) is essential for the de novo synthesis of dTMP in pro- and eucaryotic organisms. Consequently it plays a major role in the replication of the DNA genome of a cell or a DNA virus. The gene encoding the TS of Chilo iridescent virus (CIV) was identified by nucleotide sequence analysis of the viral genome and was mapped within the EcoRI CIV DNA fragments G and R. Computer assisted analysis of the DNA nucleotide sequence between the genome coordinates 0.482 and 0.489 revealed an open reading frame (ORF) of 885 nucleotides. This ORF was found to encode a polypeptide of 295 amino acid residues (33.9 kDa) that showed significant homologies to known TS of different species including mammals, plants, fungi, protozoa, bacteria, and DNA viruses. The highest amino acid homologies were found between the CIV-TS and the TS of herpesvirus ateles (54.0%), Saccharomyces cerevisiae (51.8%), herpesvirus saimiri (51.0%), rhesus monkey rhadinovirus (50.7%), mouse (50.5%), rat (50.2%), varicella-zoster virus (50.2%), equine herpesvirus 2 (50.0%), and the human TS (48.4%). The CIV-TS contains six amino acid domains that are highly conserved in the TS of other species. Within these domains the major amino acid residues are present for which a functional role has been reported. The CIV-TS was found to be more closely related to the TS of eucaryotes than to the TS of procaryotes indicating the phylogenetic origin of the CIV-TS gene. The identification of a TS gene in the genome of CIV is the first report of a viral TS that is not encoded by a herpesvirus or a bacteriophage. 相似文献
32.
Objective
Human pandemic influenza H1N1 virus as the cause of febrile respiratory infection ranging from self-limited to severe illness has spread globally during 2009. Signs and symptoms of upper and lower respiratory tract involvement, fever, sore throat, rhinitis, myalgia, malaise, headache, chills and fatigue are common. In this article we report the clinical presentation of Influenza A (H1N1) in our hospitalized children.Methods
Between September and October 2009, all children requiring hospitalization for suspected H1N1 infection were transferred to Pediatric Infectious Diseases ward. For all patients the throat swab was taken for PCR testing to confirm or exclude the diagnosis of H1N1 Influenza A. Case patients consisted of H1N1-positive patients. Age, sex, symptoms, signs, laboratory data, CXR changes, details of therapy, duration of admission and patient outcome were documented.Findings
Twenty patients were H1N1 positive. Mean age of the patients was 65.50±9.8 months. Fever and coughs were with 55% the most commonly reported symptoms. Other presentations included vomiting (55%), abdominal pain (25%), cyanosis and dyspnea (5%), body ache (40%), rhinorrhea (80%), sore throat (35%), head stiffness (5%) and loss of conciousness (5%). The median temperature of the patients was 38.5°C. Chest X-Ray changes were noted in 13 out of 20 patients (65%). Mean leukocyte and platelet was 6475 and 169000 respectively. Seventeen (85%) patients were treated with Oseltamivir, 3 patients received adjuvant antibiotics. The mean duration of admission was 3 days. Three patients required intensive care support and all of them expired due to superinfection.Conclusion
Our data confirm that the presentation of influenza in children is variable and 2009 H1N1 influenza may cause leucopenia and thrombocytopenia. 相似文献33.
The family Herpesviridae comprises at least 100 herpesviruses. Numerous human and animal pathogenic herpesviruses have been identified so far, including Cercopithecine herpesvirus 1 (CeHV-1). This virus is a member of the subfamily Alphaherpesvirinae and is the most hazardous herpesvirus to man. CeHV-1 is also known as B-virus or monkey B virus and as Herpesvirus simiae. In order to gain more genetic information, the viral DNA polymerase (DPOL) gene was identified using polymerase chain reaction (PCR) and DNA nucleotide sequence analysis. The deduced amino acid sequence contains the motifs and signatures that are typical for the B-family of DPOLs. The DPOL gene of CeHV-1 was found to be a suitable target for the specific and rapid identification of the Cercopithecine herpesvirus 1 infection by PCR technology. Comparative analysis of the DNA sequences of the DPOL gene loci of CeHV-1, Human herpesvirus 1 and 2 (HHV-1 and HHV-2), and other herpesviruses was carried out for determination of unique genomic regions of the individual DPOL genes. A primer set of 12 primers was used for screening the DNA of CeHV-1, HHV-1, and HHV-2 by detailed PCR. It was found that six out of twelve primer combinations are able to detect specifically the CeHV-1 genome without cross reactivity with the genome of HHV-1 and/or HHV-2. The specificity of the individual amplified DNA fragments was confirmed by DNA nucleotide sequence analysis. The results of these studies indicate that the six primer combinations of the specific CeHV-1 DPOL primer set is the method of choice for a rapid, precise and specific identification of a CeHV-1 infection by PCR. Due to the fact that this specific CeHV-1 DPOL primer set does not amplify any DNAs of HHV-1 or HHV-2 genome this technology is stressing and can be successfully used unlimited and more credible in all laboratories with PCR technical facility routinely for detection of a CeHV-1 infection in vivo or in vitro.The GenBank Accession No. of the sequence of DNA polymerase gene of Cercopithecine herpesvirus 1 (CeHV-1) reported in this study is AY568415, DPOL protein ID AAT67222; nuclear phosphoprotein ID AAT67223 相似文献
34.
Gholamreza Hashemi Tabar Alireza Haghparast Hassan Borji 《Comparative clinical pathology》2012,21(4):429-432
Diagnosis of hydatidosis is based on immunodiagnostic methods along with radiological and ultrasound examinations. A great number of immunological assays have been developed for detection of anti-hydatid cyst antibodies. The principal intermediate host of Echinococcus granulosus in most endemic regions of the world is sheep. Antibodies to various antigens are detectable in the sera of some, but not all infected sheep. The objective of the present study was to develop a specific and simple antigen-based ELISA method for diagnosis of hydatidosis in sheep with different (hydatid fluid, protoscolices, and whole body of E. granulosus) antigens. A total of 100 sera were collected from sheep with hydatidosis proven by inspection of hydatid-infested livers and lungs of the sheep slaughtered in Mashhad abattoir. Hydatid fluid and protoscolex were isolated from livers or lungs of sheep with hydatid cyst in sterile conditions. Whole body of E. granulosus was isolated from intestine of infected dogs. Sera samples were examined by ELISA with different antigens. The results of antibody detection by indirect ELISA, using different antigens, showed that the hydatid fluid was the most effective antigen of those assessed for detection of infection with hydatidosis in sheep. Findings of this study indicated that antibody detection assay is a sensitive approach for diagnosis of hydatid cyst in sheep. 相似文献
35.
The transmembrane domains (TMDs) of dengue virus type-1 M protein (DENV-1M) were reported to form cation-selective channels in artificial lipid bilayers. We further explored this observation using the two-electrode voltage clamp (TEVC) method on the Xenopus laevis oocytes expressing DENV PrM and M proteins. Using myc epitope tagged M proteins, M was first shown to adopt its predicted native topology in mammalian cells when expressed on its own. The recombinant proteins were then successfully expressed on the surface of Xenopus oocytes. Using influenza A M2 (Inf A/M2) protein as a control, we measured the conductance of oocytes expressing DENV proteins under hyperpolarized or low-pH conditions. Inf A/M2 showed pH-dependent, amantadine-sensitive channel activity that was consistent with previously published reports. However, no activity was detected for DENV proteins. We conclude that DENV PrM and M proteins do not show pH-activated ion channel activity. 相似文献
36.
Hassanpour G Mohebali M Raeisi A Abolghasemi H Zeraati H Alipour M Azizi E Keshavarz H 《Parasitology research》2011,108(6):1519-1523
The transmission of malaria by blood transfusion was one of the first transfusion-transmitted infections recorded in the world.
Transfusion-transmitted malaria may lead to serious problems because infection with Plasmodium falciparum may cause rapidly fatal death. This study aimed to compare real-time polymerase chain reaction (real-time PCR) with rapid
diagnostic test (RDT) and light microscopy for the detection of Plasmodium spp. in blood transfusion, both in endemic and non-endemic areas of malaria disease in Iran. Two sets of 50 blood samples
were randomly collected. One set was taken from blood samples donated in blood bank of Bandar Abbas, a city located in a malarious-endemic
area, and the other set from Tehran, a non-endemic one. Light microscopic examination on both thin and thick smears, RDTs,
and real-time PCR were performed on the blood samples and the results were compared. Thin and thick light microscopic examinations
of all samples as well as RDT results were negative for Plasmodium spp. Two blood samples from endemic area were positive only with real-time PCR. It seems that real-time PCR as a highly sensitive
method can be helpful for the confirmation of malaria infection in different units of blood transfusion organization especially
in malaria-endemic areas where the majority of donors may be potentially infected with malaria parasites. 相似文献
37.
Elahe Tajbakhsh Gholamreza Nikbakht Borujeni Hassan Momtaz 《Comparative clinical pathology》2011,20(6):635-638
Bovine immunodeficiency virus (BIV), a member of the lentivirus subfamily of retroviridae, was originally isolated from a dairy cow with persistent lymphocytosis, lymphoid hyperplasia, and prevascular cuffing in
the brain. Serological studies indicated that BIV has worldwide distribution, but its prevalence in Iran is not clearly known.
In this investigation, we report the detection of proviral DNA sequence of BIV in 300 blood samples of cattle and 150 blood
samples of sheep by polymerase chain reaction (PCR) using oligonucleotiode primers specific for the gag gene region of the virus. Blood samples of cattle and sheep were taken from Chaharmahal Bakhtiary province, Iran. According
to the PCR results, infection rate in the cattle and sheep population were 60% and 30%, respectively. This is the first report
for the presence of BIV in cattle and sheep population of Chaharmahal Bakhtiary province. 相似文献
38.
Nazanin Ebrahimi Gholamreza Asadikaram Abbas Mohammadi Yunes Jahani Mina Moridi Mohammad Masoumi 《Archives of Medical Science》2021,17(3):613
IntroductionEndothelin-1 (ET-1) is the most potent among all vasoconstrictors, and its association with cardiovascular diseases has been reported before. Our aim was to investigate the association of ET-1 plasma level and its gene polymorphisms (rs5370 and rs10478694) with hypertension and coronary atherosclerosis (CA).Material and methodsThis study was carried out on 128 women and 132 men, who were divided into 4 groups: hypertensive without atherosclerosis (H+A–); hypertensive with atherosclerosis (H+A+); non-hypertensive with atherosclerosis (H–A+); and non-hypertensive without atherosclerosis (control group). Endothelin-1 plasma levels were measured by ELISA, and gene polymorphisms were detected by polymerase chain reaction – restriction fragment length polymorphism (PCR-RFLP) methods. Coronary artery diseases (CAD) were then defined based on angiography data.ResultsThe ET-1 plasma level was significantly higher in the H+A+ group in comparison with the other groups, especially H+A–. Comparing people with CA and those without it, the highest frequency level of the T allele of rs5370 was found in people with CA. Significantly higher frequencies of the 3A allele were detected in hypertensive patients in comparison with non-hypertensive individuals, when analyzing rs10478694.ConclusionsEndothelin-1 plasma level shows a direct association with the risk of CA development. The T allele of rs5370 can be regarded as a risk factor for CA development. The 3A allele of rs10478694 can be associated with the risk of hypertension; therefore, it can be concluded that ET-1 and its gene polymorphisms play an important role in CA development and hypertension observed in the south-eastern populations of Iran. 相似文献
39.
Jamal Gharekhani Gholamreza Tavoosidana Hesamedin Akbarein 《Comparative clinical pathology》2014,23(5):1203-1207
The aim of this study was to determine the seroprevalence of Neospora caninum infection in dogs and cattle from Hamedan province (West of Iran). Blood samples were collected from 1,046 cattle and 270 dogs in this area. Cattle and dog samples were tested and analyzed using ELISA and IFAT, respectively. IgG-antibodies to N. caninum were found in 27 and 17.4 % of dogs and cattle samples, respectively. In cattle study, The association between infection and type of cattle was statistically significant (P?=?0.004). Also, significant statistical differences were observed regarding to stray canids presence in farm (P?0.0001), and abortion history (P?0.001), unlike to age (P?=?0.195) and breed (P?=?0.077). In dog study, there was statistical differences among age groups (P?0.001) and type of dogs (P?0.001) opposite to gender (P?=?0.112). This study is the first report of N. caninum infection in dogs and cattle from west of Iran. There is both horizontal and vertical transmission of N. caninum in this area, and the presence of stray dogs may be a risk factor for N. caninum infection in cattle. N. caninum is an important factor in the economic losses of the cattle breeding in Hamedan province. Therefore, further investigations and designing control strategies for improving management in cattle farms is highly recommended. 相似文献
40.
Mohammad Ashrafzadeh Takhtfooladi Gholamreza Jahanshahi Amir Sotoudeh Amirali Jahanshahi 《Comparative clinical pathology》2014,23(5):1237-1240
This study evaluated the effects of N-acetylcysteine as a scavenger of radical oxygen species on myocardial injury as a remote organ after skeletal muscle ischaemia–reperfusion. Twenty male Wistar rats were allocated randomly into two experimental groups: ischaemia–reperfusion and ischaemia–reperfusion?+?N-acetylcysteine. All animals underwent 2 h of ischaemia by occlusion of the femoral artery followed by 24 h of reperfusion. Rats treated with N-acetylcysteine were given an intravenous dose of 150 mg/kg, immediately before reperfusion. After the reperfusion period, animals were euthanized and hearts harvested for histopathological analysis under light microscopy. In the ischaemia–reperfusion group, tissues showed histological changes with interstitial oedema, neutrophil infiltration and adhesion of neutrophils to the endothelium, haemorrhage and coagulative necrosis. Histopathologically, there was a significant difference (P?0.05) between the two groups. The administration of N-acetylcysteine significantly decreased myocardial injury induced by skeletal muscle ischaemia–reperfusion according to our histological findings. 相似文献