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81.
Evidence for direct action of human biosynthetic (recombinant) GM-CSF on erythroid progenitors in serum-free culture 总被引:1,自引:0,他引:1
The biologic activity of human biosynthetic granulocyte-monocyte colony stimulating factor (GM-CSF) was investigated in serum-free culture of erythroid progenitors derived from adult peripheral blood. The morphology of erythroid bursts and the cloning efficiency of BFU-E under serum-free conditions were similar to those observed in dishes with fetal bovine serum (FBS). For these experiments, progenitor cells were partially purified by Ficoll-Paque density centrifugation, adherence to a plastic surface, and complement-mediated cytotoxicity of Leu-1+ elements. For some studies, blastlike cells were harvested directly from 6-day-old semisolid cultures. In serum-free culture of the light-density cell fraction, biosynthetic erythropoietin (Ep) was sufficient for formation of pure and mixed erythroid colonies whereas GM-CSF was required for granulocyte-monocytic colonies. When adherent and Leu-1+ cells were removed, or when in vitro differentiated blast cells were used as a source of progenitors, neither Ep or GM-CSF alone induced colony formation. In dishes supplemented with both growth factors, erythroid bursts were detected. Although the presence of GM- CSF alone did not induce formation of any colony or clusters, BFU-E were recorded when Ep was added 8 days later, suggesting that BFU-E could be maintained. Terminal maturation of the resulting erythroid bursts was delayed by 8 days. These results provide evidence that GM- CSF acts directly on early erythroid progenitors. Furthermore, they suggest that both Ep and GM-CSF are necessary to start the differentiation process. 相似文献
82.
83.
Morteza Izadi Mozhgan Fazel Seyed Hassan Saadat Mohammad Hassan Nasseri Mojtaba Ghasemi Hossein Dabiri Reza Safi Aryan Ali Akbar Esfahani Ali Ahmadi Davood Kazemi-Saleh Mohammad Hassan Kalantar-Motamed Saeed Taheri 《Methodist DeBakey Cardiovascular Journal》2012,8(2):42-46
It has been shown that cytomegalovirus (CMV) is present in coronary atherosclerotic plaques, but the clinical rele-vance of this presence remains to be elucidated. In this study we sought to examine CMV infection in atherosclerosis patients defined by different methods and to identify the clinical significance of CMV replication in the atherosclerotic plaques. The study included 105 consecutive patients who were admitted to our department and underwent coronary artery bypass grafting (CABG) surgical interventions. Coronary atherosclerotic specimens as well as 53 specimens from the mamillary artery of these same patients were analyzed. Enzyme-linked immunosorbent assay (ELISA) and poly-merase chain reaction (PCR) methods were used for evaluations. The CMV PCR test result was positive for 28 (26.7%) of patients with coronary artery atherosclerosis. After adjusting for other risk factors, coronary artery disease patients with a history of acute coronary syndrome were more likely to be positive for CMV PCR test (P=0.027; odds ratio: 4.2; 95% CI: 1.18-15.0). They were also more likely to have a positive family history for cardiovascular diseases (CVD). This study confirms previous evidence about the replication of CMV virus in the atherosclerotic plaques of coronary arteries and brings clinical significance to this observation by showing a higher prevalence of acute coronary syndromes in those patients with CMV-infected plaques. Our study also suggests a familial vulnerability to CMV replication in the coronary artery walls. 相似文献
84.
M Tavassoli S Javadi R Firozi F Rezaei AR Khezri M Hadian 《Iranian Journal of Parasitology》2012,7(4):110-115
Background
We tried to investigate the hair contamination of pet dogs and farm sheepdog with Toxocara eggs in terms of the different sex and age groups in north-west of Iran (Urmia and its suburbs).Methods
Hair samples were collected from a total of 138 pet and farm sheepdogs from November 2008 to June 2009 in Urmia City and the suburb (West Azerbaijan-Iran) and examined for the presence of T. canis eggs.Results
T. canis eggs found in 60 samples altogether (pet and shepherd dogs) showed a contamination rate of 36.2%. The number of observed T. canis eggs in each microscope field was varied from 1 to > 400. The age of the dog was found a significant factor to influence the prevalence and intensity of contamination, with 82% of all the eggs recovered from puppies (six months and younger). Additionally, the numbers of eggs in farm sheepdogs were significantly higher than pet dogs (P<0.05).Conclusion
This report shows that direct contact with T. canis infected dogs, particularly puppies from shepherd dogs, may pose a serious hazard to human. Besides, as they may harbor a considerable number of eggs on their hair, they can contaminate the soil and the environment. 相似文献85.
Background
Hadjelia truncata is a nematode that causes lesions in the gizzard lining of pigeons, which may even lead to death. The aim of this study was to introduce Alphitobius diaperinus as a new intermediate host for Hadjelia truncata.Methods
H. truncata infection was identified in a pigeon flock in Ahvaz City, Khuzestan Province, Iran by performing fecal examination and autopsy. Adult and larval stages of beetles were collected from the litter of pigeon houses, and identified morphologically. The beetle larvae were cultured in a medium, containing feces of the infected pigeons. Nematode larval stages from naturally and experimentally (culturally) infected adult beetles were fed to two groups of pigeonsResults
The collected beetles were identified as Alphitobius diaperinus. Average length and width of the adult beetles were 6.31 mm and 2.88 mm respectively. Infection rates of naturally and experimentally infected beetles with larval stages of the nematode were 66.2% and 45.1% respectively. The adult nematodes collected from gizzards of experimentally infected pigeons were identified as H. truncata. Nematode infection rates in pigeons after feeding the infective larvae collected from naturally and experimentally infected beetles were 44.7% and 32.5% respectively.Conclusion
A. diaperinus can serve as a natural intermediate host for H. truncata. 相似文献86.
Setarehbadi R Vatannejad A Vaisi-Raygani A Amiri I Esfahani M Fattahi A Tavilani H 《Systems biology in reproductive medicine》2012,58(5):263-267
Lipid components of spermatozoa have an important role in the functional activity of this cell. The protein, apolipoprotein E (apoE), has a central role in lipid transport. The aim of this study was to investigate the distribution of APOE genotypes, ?3?3, ?3?4, and ?2?3, and the corresponding alleles in fertile and infertile males, and to assess the semen parameters from the patients carrying the different alleles. In addition, the levels of cholesterol, phospholipid, and triacylglycerol in spermatozoa, isolated by PureSperm gradient and from seminal plasma in samples from infertile males was compared with respect to the APOE genotype. APOE genotypes were determined by PCR-RFLP on DNA extracted from peripheral blood leucocytes in 108 fertile and 107 infertile men. There was a significant difference between the distribution of APOE genotypes in fertile as compared to infertile males (χ(2)?=?9.1, df?=?2, p?=?0.011). The presence of genotype ?3?4 conferred a 3.82 risk factor for male infertility {Odds ratio?=?3.82 (1.46-10, p?=?0.006)}. Our findings showed that the distribution of APOE genotypes and alleles differed between fertile and infertile individuals and may be a risk factor for male infertility. We suggest that the effects of APOE genotypes may be linked to differences in the efficacy of the expressed apoE isoforms in promoting sperm maturation during epididymal transit. 相似文献
87.
Esfahani AN Hassani AH Farshchi P Morowati M Moatar F Karbassi A 《Bulletin of environmental contamination and toxicology》2012,88(6):850-857
A total of 48 water samples and 24 sediment samples were collected at four sampling stations along the wetland during four
seasons from 2009 to 2010 and analyzed by gas chromatograph–electron capture detector (GC–ECD). In water the total concentration
of OCPs was 0.33, 0.01, 0.1 and 0.07 mg/L in summer, autumn, winter and spring, respectively. The most frequent OCP compounds
detected were endrin and chlordane (0.08 and 0.07 mg/L), heaxachlorobenzene and chlordane (0.06, 0.02 mg/L), and chlordane
(0.07 mg/L) in summer, winter and spring, respectively. The maximum concentration of ΣOCPs was found in samples collected
from station 1 in summer (0.26 mg/L). In sediments the total concentrations of OCPs were 15.84 and 2.62 mg/g-dry weight (dw)
in summer and winter, respectively. Chlordane was the most frequently found OCP compound, followed by lindane, 9.92 and 2.47 mg/g-dry
weight (dw), respectively, in summer. While, lindane (2.52 mg/g-dw) and endosulfan I (0.1 mg/g-dw) were the highest OCP compounds
detected in winter. The results obtained in this study show that there still exist a variety of organochlorine pesticide residues
in the water and sediments from the Amir-kalaye wetland in Iran. 相似文献
88.
Larijani B Esfahani EN Amini P Nikbin B Alimoghaddam K Amiri S Malekzadeh R Yazdi NM Ghodsi M Dowlati Y Sahraian MA Ghavamzadeh A 《Acta medica Iranica》2012,50(2):79-96
Stem cells are undifferentiated cells with the ability of proliferation, regeneration, conversion to differentiated cells and producing various tissues. Stem cells are divided into two categories of embryonic and adult. In another categorization stem cells are divided to Totipotent, Multipotent and Unipotent cells.So far usage of stem cells in treatment of various blood diseases has been studied (such as lymphoblastic leukemia, myeloid leukemia, thalassemia, multiple myeloma and cycle cell anemia). In this paper the goal is evaluation of cell therapy in treatment of Parkinson's disease, Amyotrophic lateral sclerosis, Alzheimer, Stroke, Spinal Cord Injury, Multiple Sclerosis, Radiation Induced Intestinal Injury, Inflammatory Bowel Disease, Liver Disease, Duchenne Muscular Dystrophy, Diabetes, Heart Disease, Bone Disease, Renal Disease, Chronic Wounds, Graft-Versus-Host Disease, Sepsis and Respiratory diseases. It should be mentioned that some disease that are the target of cell therapy are discussed in this article. 相似文献
89.
In vitro evaluation of prothrombin complex concentrates in a thrombin generation assay, using DAPA and purified components of the prothrombinase complex, demonstrated significant levels of coagulant- active "phospholipid replacing" activity. Quantification of this activity showed a significant correlation (r = 0.8747, p less than 0.01) with thrombogenicity measured in vivo in a stasis model in rabbits. Extracted lipid material retained full phospholipid replacing activity in the vitro assay. Thin-layer chromatographic characterization confirmed the presence of phospholipids with known coagulant activity in vitro. In vivo, the extracted material was nonthrombogenic but augmented the thrombogenicity of purified factor Xa. Substitution of a synthetic coagulant-active phospholipid (phosphatidylcholine-phosphatidylserine lipid vesicles) for the extracted phospholipid produced a similar augmentation of a factor-Xa- induced thrombogenicity in vivo. It is concluded that the coagulant- active phospholipid content of prothrombin complex concentrates is a major determinant of thrombogenicity but requires the presence of activated clotting factors for its expression in vivo. 相似文献
90.
Drug-induced thrombocytopenia is associated with increased binding of IgG to platelets both in vivo and in vitro 总被引:3,自引:0,他引:3
Kelton JG; Meltzer D; Moore J; Giles AR; Wilson WE; Barr R; Hirsh J; Neame PB; Powers PJ; Walker I; Bianchi F; Carter CJ 《Blood》1981,58(3):524-529
Thrombocytopenia is a common serious adverse effect of drug treatment. A variety of in vitro diagnostic techniques to confirm the diagnosis are available, but the majority lack sufficient sensitivity to detect all cases of drug-induced thrombocytopenia. We studied 19 patients with suspected drug-induced thrombocytopenia and demonstrated that platelet- associated IgG (PAIgG) was elevated in all at the time of thrombocytopenia, and PAIgG returned to normal levels as the thrombocytopenia resolved. In the majority of patients, the platelet count rapidly returned to normal after the drug was discontinued; however, in six patients, the thrombocytopenia persisted well beyond the period of time that the offending drug would be expected to be cleared from the blood. In 13 patients, serum obtained after recovery was used to identify the drug responsible for the thrombocytopenia in an in vitro assay. In all cases, the addition of the drug historically associated with the thrombocytopenic episode was associated with an increased binding of IgG to control platelets. For uncertain reasons, the concentration of drug required to increase the in vitro binding of IgG to test platelets was often more than the concentration usually achieved in vivo. Wider application of these techniques may provide better understanding of the clinical characteristics and mechanisms responsible for drug-induce thrombocytopenia. 相似文献