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31.

Cardiovascular diseases are a growing problem in developing countries; therefore, there is an ongoing intensive search for new approaches to treat these disorders. Currently, cellular therapies are focused on healing the damaged heart by implanting stem cells modified with pro-angiogenic factors. This approach ensures that the introduced cells are capable of fulfilling the complex requirements of the environment, including the replacement of the post-infarction scar with cells that are able to contract and promote the formation of new blood vessels that can supply the ischaemic region with nutrients and oxygen. This study focused on the genetic modification of human skeletal muscle cells (SkMCs). We chose myoblast cells due to their close biological resemblance to cardiomyocytes and the placental growth factor (PlGF) gene due to its pro-angiogenic potential. In our in vitro studies, we transfected SkMCs with the PlGF gene using electroporation, which has previously been proven to be efficient and generate robust overexpression of the PlGF gene and elevate PlGF protein secretion. Moreover, the functionality of the secreted pro-angiogenic proteins was confirmed using an in vitro capillary development assay. We have also examined the influence of PlGF overexpression on VEGF-A and VEGF-B, which are well-known factors described in the literature as the most potent activators of blood vessel formation. We were able to confirm the overexpression of VEGF-A in myoblasts transfected with the PlGF gene. The results obtained in this study were further verified in an animal model. These data were able to confirm the potential therapeutic effects of the applied treatments.

  相似文献   
32.
Use of spectroscopic probes for detection of reactive oxygen species   总被引:2,自引:0,他引:2  
The detection and quantitation of reactive oxygen species (ROS) receives a great deal of interest because of their importance in a wide range of physiological and pathogenic events. Probe-assisted spectroscopy (electron spin resonance, spectrophotometry, fluorescence and luminescence) is the main tool for this application. This review discusses the properties of spectroscopic probes most commonly used for ROS detection and highlights their limitations in cellular systems. These include poor stability of some probes and/or products that may be subjected to cellular metabolism and lack of specificity in their reactions with oxidants or reductants. Additional problems often arise from undesired reactions of the probes and from their non-homogeneous distribution in the studied system, production of ROS by the probes themselves, perturbation of the systems under investigation by the probes, and artifacts due to the presence of ROS in the reaction medium. The limits imposed by these difficulties on the precise evaluation of the amounts and rates of formation of ROS are discussed critically.  相似文献   
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The clinical specimens received from patients hospitalized in Department of Thoracic Surgery between 1997 and 2001 were microbiologically examined. The main specimen for microbiological examination was pleural fluid (median 34%). The frequency of specimens from bronchial tree increased significantly (from 4% to 26%) with concurrent decrease of sputum (from 29% to 6%). Among isolated pathogens, Gram negative rods were the most frequent (median 48%) and Pseudomonas sp. was the main pathogen among them. Occurrence of staphylococci was median 22% and Staphylococcus aureus, with a little decrease in analyzed period, was still the main Gram positive pathogen. Simultaneously the occurrence of MRSA in the last three years dropped three times. The number of isolations of yeasts have risen from 5.8% to 10.3%.  相似文献   
35.
Intracranial infectious aneurysms, or mycotic aneurysms, are rare infectious cerebrovascular lesions which arise through microbial infection of the cerebral arterial wall. Due to the rarity of these lesions, the variability in their clinical presentations, and the lack of population-based epidemiological data, there is no widely accepted management methodology. We undertook a comprehensive literature search using the OVID gateway of the MEDLINE database (1950–2009) using the following keywords (singly and in combination): “infectious,” “mycotic,” “cerebral aneurysm,” and “intracranial aneurysm.” We identified 27 published clinical series describing a total of 287 patients in the English literature that presented demographic and clinical data regarding presentation, treatment, and outcome of patients with mycotic aneurysms. We then synthesized the available data into a combined cohort to more closely estimate the true demographic and clinical characteristics of this disease. We follow by presenting a comprehensive review of mycotic aneurysms, highlighting current treatment paradigms. The literature supports the administration of antibiotics in conjunction with surgical or endovascular intervention depending on the character and location of the aneurysm, as well as the clinical status of the patient. Mycotic aneurysms comprise an important subtype of potentially life-threatening cerebrovascular lesions, and further prospective studies are warranted to define outcome following both conservative and surgical or endovascular treatment.  相似文献   
36.
BACKGROUND: The etiology of bipolar disorder (BD) and schizophrenia is very complex. Polymorphic variants of genes encoding enzymes of the monoaminergic may be involved in development of BD and schizophrenia. Therefore, we examined the prevalence of 1958G>A polymorphism of MTHFD1 gene, encoding trifunctional folate enzyme 5,10-methylenetetrahydrofolate dehydrogenase, 5,10-methenyltetrahydrofolate cyclohydrolase and 10-formyltetrahydrofolate synthetase (MTHFD1), and 2756A>G variant of methionine synthase (MTR) gene in patients with BD (n=200), schizophrenia (n=200) and in controls (n=300). OBJECTIVE: We investigated the genotypic and allelic frequencies of MTHFD1 1958G>A (R653Q) and MTR 2756A>G (D919G) gene polymorphisms in a group of bipolar (n=200) and schizophrenic patients (n=200), as well as in controls (n=300). METHODS: The distributon of genotypes in all groups was tested for deviation from Hardy-Weinberg equilibrium (HWE). The Pearson's chi-square (chi) test and Fisher's exact test were applied to assess differences in the genotypic and allelic (respectively) distribution between groups of patients and controls. MAIN RESULTS: We found that MTHFD1 1958AA or 1958AG genotypes constitute risk factors for development of bipolar disorder type I (BDI) or schizophrenia with odds ratios (OR)=1.743 (95% CI=1.211-2.508; P=0.0027; P (corr)=0.0054) and 2.667 (95% CI=1.845-3.854; P=0.0001; P (corr)=0.0002), respectively. In the same groups, the MTR 2756GG or 2756AG genotypes also constitute significant risk factors in occurrence of BDI and schizophrenia with OR=1.621 (95% CI=1.130-2.326; P=0.0086; P (corr)=0.0172) and 1.556 (95% CI=1.085-2.232; P=0.0160; P (corr)=0.032), respectively. Gender classification of patients indicated significant association only of MTHFD1 1958A allele with BDI and schizophrenia in the male patients OR=1.838 (95% CI=1.114-3.031; P=0.0166; P (corr)=0.0332) and OR=3.964 (95% CI=2.358-6.663; P=0.0001 P (corr)=0.0002), respectively. CONCLUSION: Since MTHFD and MTR genes are located in 14q24 and 1q43 loci, our findings support the significance of chromosomes 14q and 1q in etiopathogenesis of bipolar disorder and schizophrenia.  相似文献   
37.
Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. This tumor typically expresses KIT, and has KIT or PDGFRA activating mutation. In this study we evaluated 89 GISTs diagnosed in Northern Norway during a 30-year period. KIT exons 8, 9, 11, 13, and 17 were analyzed by PCR amplification and direct sequencing. Subsequently PDGRA exons 12, 14, and 18 were evaluated in KIT wild-type cases. KIT mutations were found in 66 cases (75%), and PDGFRA mutations in 9 cases (10%). Most common were KIT exon 11 mutations, with 58 cases. Tumors with Kit exon 11 point mutations had a significantly better prognosis than those with deletions. There were five KIT exon 9 duplications, three exon 13 point mutations, and one point mutation in exon 17. There were nine PDGFGRA mutations: seven in exon 18 and two in exon 12. All but one PDGFRA mutant GISTs were gastric tumors with epithelioid morphology, and these tumors were on average smaller than those with KIT mutations. KIT and PDGFRA wild type was found in 15% of cases. Analysis of KIT and PDGFRA mutations is of significance for treatment with tyrosine kinase inhibitors, and may also have value when assessing the biological potential of GIST.  相似文献   
38.
Familial Mediterranean Fever (FMF) is a disease with an autosomal recessive inheritance affecting inhabitants of the Mediterranean Sea basin area. It is the most prevalent fever-inflammatory syndrome manifested by fever episodes, serositis and rash. The symptoms regress spontaneously and between recurrent attacks of fever the child is healthy. Amyloidosis is the most serious complication. A case of a 8 year-old boy, a son of Armenian immigrants, with recurrent pleuritis is presented.  相似文献   
39.
Diabetes mellitus (DM) is a heterogeneous group of disorders whose common trait is chronic hyperglycemia. Gestational diabetes mellitus (GDM) is one of the subtypes of DM that manifests during pregnancy. It is believed that 2%–5% of pregnancies worldwide are complicated with GDM, with the prevalence having significantly increased over the last decade. While the pathogenesis of the disease remains largely unknown, GDM is believed to be a result of interactions between genetic, epigenetic, and environmental factors. Linkage and association studies, including those that are genome-wide, have allowed us to identify complex genetic and epigenetic mechanisms that lead to the development of GDM. Multiple common variants in candidate genes such as potassium inwardly rectifying channel subfamily J, member 11 (KCNJ11), glucokinase (GCK), or hepatocyte nuclear factor 1α (HNF1A) have been found to increase the disease risk. In this review, we provide a detailed overview of the current knowledge concerning the influence of genetics and epigenetics on the development of GDM.  相似文献   
40.
Growth deficiency is one of the most frequent causes of referral to Endocrinology Outpatient Clinic. IGF-1 (insulin-like growth factor 1) deficiency is one of the rarest causes of short stature. In 2009 in Poland a therapeutic programme was set up for children with severe primary IGF-1 deficiency. The authors present the data of three first polish patients qualified for the rhIGF-1 (recombinant human insulin-like growth factor 1) - mecasermin. The authors conclude that the treatment with rhIGF-1 significantly improves growth velocity in patients with IGF-1 deficiency. During two years of mecasermin treatment no serious side effects were noted.  相似文献   
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