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1.
Certification represents the first line of defense against fruit tree viruses. For certification or surveys dealing with large number of samples, ELISA is still considered the technique of choice and requires a continuous supply of good quality antibodies. Prune dwarf virus (PDV) is among the major viruses affecting stone fruits; it belongs to the genus Ilarvirus named so for its isometric labile particles. Recombinant DNA technology was investigated for production of PDV antiserum to avoid labile virus purification and virus maintenance problems. The PDV coat protein gene (CP) was cloned into a protein expression bacterial plasmid vector which allowed a good level of expression of up to 2mg native protein/L culture. The recombinant PDV CP was injected into rabbits and the crude antiserum was successfully used in indirect ELISA at dilutions of up to 1:5000 to detect PDV in infected leaf samples. Similar results were obtained in dot blot immunoassays (DBIA). The antibodies were used in double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) and results were comparable to a reference commercial kit. The crude antiserum was efficiently used for coating ELISA plates, thereby reducing test costs.  相似文献   
2.
We are currently facing an obesity pandemic, with worldwide obesity rates having tripled since 1975. Obesity is one of the main risk factors for the development of non-communicable diseases, which are now the leading cause of death worldwide. This calls for urgent action towards understanding the underlying mechanisms behind the development of obesity as well as developing more effective treatments and interventions. Appetite is carefully regulated in humans via the interaction between the central nervous system and peripheral hormones. This involves a delicate balance in external stimuli, circulating satiating and appetite stimulating hormones, and correct functioning of neuronal signals. Any changes in this equilibrium can lead to an imbalance in energy intake versus expenditure, which often leads to overeating, and potentially weight gain resulting in overweight or obesity. Several lines of research have shown imbalances in gut hormones are found in those who are overweight or obese, which may be contributing to their condition. Therefore, this review examines the evidence for targeting gut hormones in the treatment of obesity by discussing how their dysregulation influences food intake, the potential possibility of altering the circulating levels of these hormones for treating obesity, as well as the role of short chain fatty acids and protein as novel treatments.  相似文献   
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Sea urchin metallothionein sequence: key to an evolutionary diversity.   总被引:10,自引:3,他引:10       下载免费PDF全文
The metallothioneins (MTs) constitute a diverse family of proteins, which are enriched in cysteines and bind heavy metals. The amino acid sequence of sea urchin MT has been obtained from its mRNA sequence and compared with MT sequences of various sources. A largely conserved sequence of 10 amino acids, the "central segment," is located near the center of the MT molecules of Neurospora, yeast, and Drosophila and the center of putative domains in mammalian and sea urchin MTs. The sea urchin carboxyl-terminal-half MT resembles the mammalian 9-cysteine amino-terminal MT domain I, both in the presence of this central segment and in the relative placement of cysteine residues. Conversely, the sea urchin amino-terminal-half MT, containing 11 cysteines, resembles the mammalian carboxyl-terminal MT domain II in its exclusive enrichment in vicinal cysteines. The reversed order of these sea urchin and mammalian MT halves appears to be just one aspect of a diversity based on the elaboration of structures containing the central segment. Still another variation in this diversity is the duplication of the central segment, apparent in Drosophila and crab MTs.  相似文献   
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Pure hair and nail ectodermal dysplasia (PHNED) is a rare genetic disorder characterized by hypotrichosis or complete alopecia, as well as nail dystrophy. Mutations in the type II hair keratin gene KRT85 and the HOXC13 gene on chromosome 12q have recently been identified in families with autosomal‐recessive PHNED. In the present study, we have analyzed a consanguineous Syrian family with an affected girl having complete alopecia and nail dystrophy since birth. The family clearly showed linkage to chromosome 12q13.13–12q14.3, which excluded the KRT85 gene. Sequencing of another candidate gene HOXC13 within the linkage interval identified a homozygous frameshift mutation (c.355delC; p.Leu119Trpfs*20). Expression studies in cultured cells revealed that the mutant HOXC13 protein mislocalized within the cytoplasm, and failed to upregulate the promoter activities of its target genes. Our results strongly suggest crucial roles of the HOXC13 gene in the development of hair and nails in humans.  相似文献   
7.

Objectives:

To explore the spectrum of pathologies diagnosed in prostatic biopsies of Saudi men, and test whether the frequency of diagnosing the malignant fraction has been changed over the last 15 years, and assess the association between chronic inflammation (CI) with both benign prostatic hyperplasia (BPH) and cancer (PCa), and investigate the histological findings of cases presented with acute urinary retention (AUR) clinically.

Methods:

This is a retrospective cohort study including all prostatic biopsies accessed in the files in the Surgical Pathology Laboratory of King Fahd University Hospital, Alkhobar, Kingdom of Saudi Arabia over 15 years (1999-2013) for Saudi men. Age, procedure indication, and final diagnoses were retrieved and slides were reviewed.

Results:

There were 360 cases included in this study with a median age of 65 year-old. The BPH comprised the most (64.7%), while PCa accounted for 89 cases, 13.5% of which were incidental. Most cases of both BPH and PCa were diagnosed in the seventh decade. The frequency of diagnosing PCa did not show a solid rise or fall over time. Chronic inflammation is more related to BPH than to PCa. Only CI showed a significant statistical association with AUR.

Conclusion:

Prostatic diseases show a stable trend over time. While CI is a common dominator for both BPH and PCa, it is associated more with BPH. Among all histological findings, only CI is related to the clinical presentation of AUR.The spectrum of prostatic diseases is a common health concern all over the world. While benign prostatic hyperplasia (BPH) is the most frequent urologic diagnosis in elderly males worldwide, affecting approximately one third of males in their 60’s,1,2 prostatic carcinoma (PCa) is the second most common cause of cancer-related death in males after lung cancer.3 The disease represents clear racial and national differences, with its highest incidence in blacks in the West, and lowest in Asian males.4 Recently, there has been a rising trend for PCa in populations that are thought to be of low risk.5 Furthermore, the relationship between chronic inflammation (CI) and presence and progression of both BPH and PCa is controversial.6-9 On the other hand, acute urinary retention (AUR), which is the most frequent emergency in urology, is mostly developed in a background of BPH.10 Whether other pathologies, such as CI and infarction increase the risk of this complication is debated.11-13 In this work, we retrospectively reviewed the whole spectrum of prostatic pathologies diagnosed in our center during the last 15 years, including prostatic intraepithelial neoplasia (PIN) and atypical small acinar proliferation (ASAP), and study various diseases in relation to age of diagnosis, explore the change in trend of diagnosing PCa over a period witness an increase in screening and gradual westernization of lifestyle, test the relationship between CI and both BPH and PCa, and also, we investigate the role of different biopsy findings in relation to the clinical presentation with AUR.  相似文献   
8.
Solute carrier family 22 member 5 (SLC22A5) encodes a sodium‐dependent ion transporter responsible for shuffling carnitine across the plasma membrane. This process provides energy for the heart, among other organs allowing beta‐oxidation of fatty acids. Mutations in SLC22A5 result in primary carnitine deficiency (PCD), a disorder that manifests with cardiac, skeletal, or metabolic symptoms. We hereby describe two novel mutations in SLC22A5 in two Lebanese families associated exclusively with a cardiac phenotype. The frequency of the cardiac, metabolic and skeletal symptoms in PCD patients remains undefined. All the reported eight PCD patients belonging to five different Lebanese families have an exclusive cardiac phenotype. Carnitine levels appear to be directly linked to the type and position of the mutation and the severity of the phenotypic presentation does not seem to be associated with serum carnitine levels. A comprehensive review of 61 literature‐reported PCD cases revealed an exclusive cardiac manifestation frequency at 62.3% with a very low likelihood of simultaneous occurrence of cardiac and metabolic manifestation.  相似文献   
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10.
Angiogenesis has a significant pathogenic role in liver damage-associated hepatitis C virus infection. We evaluated whether chronic hepatitis C (CHC) is associated with elevated levels of angiogenesis marker (vascular endothelial growth factor) and whether it is modulated by therapy. Vascular endothelial growth factor (VEGF) mRNA was determined in the 36 CHC patients included in this study before therapy and 12 weeks after receiving antiviral combination therapy, pegylated interferon alpha-2b plus ribavirin, compared to 20 healthy controls. CHC patients showed elevated baseline VEGF level before and during treatment, but it was decreased in responder group, indicating a shift toward an “anti-angiogenic” process in CHC patients. In conclusion, this suggests that VEGF mRNA level could be useful as non-invasive, base markers of response to therapy.  相似文献   
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