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71.
We report here the generation of recombinant vesicular stomatitis virus (VSV) able to produce the suicide gene product thymidine kinase (TK) or cytokine interleukin 4 (IL-4). In vitro cells infected with the engineered viruses expressed remarkably high levels of biologically active TK or IL-4 and showed no defects in replication compared to the wild-type virus. Recombinant viruses retained their ability to induce potent apoptosis in a variety of cancer cells, while normal cells were evidently more resistant to infection and were completely protected by interferon. Significantly, following direct intratumoral inoculation, VSV expressing either TK or IL-4 exhibited considerably more oncolytic activity against syngeneic breast or melanoma tumors in murine models than did the wild-type virus or control recombinant viruses expressing green fluorescent protein (GFP). Complete regression of a number of tumors was achieved, and increased granulocyte-infiltrating activity with concomitant, antitumor cytotoxic T-cell responses was observed. Aside from discovering greater oncolytic activity following direct intratumoral inoculation, however, we also established that VSV expressing IL-4 or TK, but not GFP, was able to exert enhanced antitumor activity against metastatic disease. Following intravenous administration of the recombinant viruses, immunocompetent BALB/c mice inoculated with mammary adenocarcinoma exhibited prolonged survival against lethal lung metastasis. Our data demonstrate the validity of developing novel types of engineered VSV for recombinant protein production and as a gene therapy vector for the treatment of malignant and other disease.  相似文献   
72.
Chromosomes undergo dramatic morphological changes as cells advance through the cell cycle. Using powerful molecular and computational methods, several recent studies revealed an outstanding complexity of continuous structural changes accompanying cell cycle progression. In agreement with cell division being a fundamental cellular process, characteristic features of cell cycle stage‐specific genome structure are conserved from yeast to mouse. These studies further shine light on the critical roles that SMC complexes, already well known as fundamental regulators of chromosome topology, have in orchestrating structural dynamics throughout the cell cycle.  相似文献   
73.
Acute, subchronic and chronic effects of the P-9801091 plant mixture extract at a dose of 20 mg/kg body mass were assessed in serum of healthy CBA/HZg mice at 24 hours, 7 days, 3 months and 6 months of treatment (experimental group), and compared with the values obtained in the control group of untreated healthy CBA/HZg mice. The P-9801091 plant mixture extract is an antihyperglycemic preparation containing Myrtilli folium (Vaccinium myrtillus L.), Taraxaci radix (Taraxacum officinale Web.), Cichorii radix (Cichorium intybus L.), Juniperi fructus (Juniperus communis L.), Centaurii herba (Centaurium umbellatum Gilib.), Phaseoli fructus sine semine (Phaseolus vulgaris L.), Millefolii herba (Achillea millefolium L.), Mori folium (Morus nigra L.), Valerianae radix (Valeriana officinalis L.) and Urticae herba et radix (Urtica dioica L). Toxic effect of the P-9801091 plant mixture extract was assessed by the following biochemical parameters: urea, creatinine, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and cholesterol. Also, histopathological examination of the kidneys, liver, spleen, pancreas, testes and lungs was performed. Results of biochemical testing performed at specified time points generally showed no statistically significant differences from control values, with the only exception of the catalytic concentration of AST in the experimental group measured on day 7, which was significantly increased as compared with the control group (p<0.05). Pathohistological examination including characteristic organ and tissue structure, and parenchyma relationship to the adjacent blood vessels and connective tissue in the examined organs revealed no major pathologic changes.  相似文献   
74.
Six female patients with encephalitis, mean age 36.5 (17-60) years, were admitted to the hospital during the 2000-2001 influenza A (H1N1) epidemic in the Osijek--Baranja County. In three (50.0%) patients, the manifestation of encephalitis occurred on day 4 or 5, and in two (33.3%) patients within 24-48 hours of the onset of influenza symptoms. The disease manifestations included headache, elevated body temperature, generalized fatigue, and consciousness disturbance through coma. Three (50.0%) patients had grand mal seizures. Pathologic electroencephalography findings were recorded in all six (100%) patients, whereas computed tomography showed cerebral edema in three (50.0%) patients. Elevated levels of hepatic enzymes and peripheral blood leukopenia were found in two (33.3%) patients in whom encephalitis developed early upon the onset of influenza. One (16.6%) of these patients died, whereas permanent sequels remained in the other two (33.3%) patients.  相似文献   
75.
Archaeologists, in most cases, neglect animal bones and teeth, which present common material on archaeological sites. Analysis of archaeozoological material from Vucedol (Baden culture) and prehistoric cave site Vela spila on Korcula, has been applied to stress the importance of that material (especially single animal teeth) in archaeozoological samples. It is obvious that a higher percentage of single teeth influence the number of identified animal species on particular sites. One species were identified only by teeth. For the reconstruction of the environment and behavior of ancient peoples, every evidence obtained from sites is important, and because of that sieving must be part of every excavation.  相似文献   
76.
We determined the temporal stability of T wave alternans (TWA) during constant rate stimulation and the dependence of alternans on heart rate (HR) and beta-adrenergic stimulation. Although it is established that exercise can provoke microvolt-level TWA in patients at risk for reentrant ventricular arrhythmias, the mechanisms underlying TWA in humans are not well understood. Specifically, the temporal stability of alternans at any given HR and the influence of HR vs. sympathetic activation on alternans remain unclear. TWA was measured during prolonged fixed-rate atrial pacing at multiple cycle lengths (CLs) in 10 subjects referred for electrophysiological testing and in 14 additional subjects in whom atrial pacing was performed at identical pacing CLs with and without isoproterenol. During constant CL stimulation, TWA amplitude oscillated significantly over time (typically by 10 microV) in a quasiperiodic fashion with periodicity of approximately 2-3 min. Alternans amplitude was strongly dependent on HR but not on adrenergic stimulation. There was a patient-specific threshold HR over which alternans appeared. At higher HR, alternans amplitude increased and oscillations were less prominent. Adrenergic stimulation was required to produce TWA that was not already elicited by moderate elevation of HR in only 2 of 14 (14%) patients. In conclusion, TWA 1) fluctuates spontaneously over 2-3 min and 2) increases monotonically with increased HR (without a major adrenergic contribution in most patients). These data suggest that increased HR rather than sympathetic activation is responsible for arrhythmogenic microvolt-level TWA measured during exercise.  相似文献   
77.
78.
Hydrobiologia - Identifying the evolutionary and developmental bases of adaptive phenotypes is of central interest in evolutionary biology. Cichlid fishes have been a useful research model due to...  相似文献   
79.
Autoimmune thyroid diseases (AITD) are multifactorial endocrine diseases most frequently accompanied by Tg and TPO autoantibodies. Both antibodies have a higher prevalence in females and act under a strong genetic influence.To identify novel variants underlying thyroid antibody levels, we performed GWAS meta-analysis on the plasma levels of TgAb and TPOAb in three Croatian cohorts, as well as gender specific GWAS and a bivariate analysis.No significant association was detected with the level of TgAb and TPOAb in the meta-analysis of GWAS or bivariate results for all individuals. The bivariate analysis in females only revealed a genome-wide significant association for the locus near GRIN3A (rs4457391, P = 7.76 × 10?9). The same locus had borderline association with TPOAb levels in females (rs1935377, P = 8.58 × 10?8).In conclusion, we identified a novel gender specific locus associated with TgAb and TPOAb levels. Our findings provide a novel insight into genetic and gender differences associated with thyroid antibodies.  相似文献   
80.
In this study we reported the results for the first time of applying Polymerase Chain Reaction-Short Tandem Repeats (PCR-STR) method in the field of detection of aneuploidies for chromosomes 21 and 18 in Croatians. The aims of the study were: (I) validation of the diagnostic informativeness of 6 STR loci (D18S51, D18S858, D18S535, D21S1435, D21S1411, and D21S1414) in sample of 205 unrelated healthy individuals; (II) evaluation of diagnostic power of the PCR-STR method for those 6 microsatellites; (III) establishment protocol for use STRs as routine method for rapid prenatal detection of trisomy 21 and 18. DNA samples were amplified by fluorescence-based PCR reaction, subjected to electrophoresis in automated laser fluorescence DNA sequencer (ALFexpress). Results of our study were: (I) all 6 tested loci are informative (68-85% of heterozygous individuals); (II) comparison between PCR-STR method and conventional cytogenetics did not revealed any false positive or false negative results; (III) in prenatal screening of 105 samples of uncultured amniotic fluid 6 (5.7%) samples with chromosomal abnormalities were identified.  相似文献   
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