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Background

Although uncommon in teenagers and young adults, cancer is the leading cause of non-accidental death in those aged 15–24 years. A prolonged period to cancer diagnosis in this cohort is reported and thought to be a consequence of the rarity of cancer in this age group, together with the complexity of presenting symptoms. Although diagnostic delay is perceived to be a problem for teenagers and young adults with cancer, little research has focused on their use of primary care services.

Aim

To determine how often teenagers and young adults consult, their reasons for doing so, and how often potential oncological symptoms (‘alert’ symptoms) appear.

Design and setting

Retrospective audit of consultations over 1 year. Three general medical practices in Scotland.

Method

Medical records were examined for 2326 teenagers and young adults. Date of birth, sex, and free-text relating to the consultation were recorded and coded according to an agreed coding system; symptoms of potential oncological significance were coded as alert symptoms.

Results

A total of 1659 teenagers and young adults (71.3% of registered patients) attended their GP at least once. Females attended more frequently than males (P<0.001), and older females more frequently than younger females (P<0.001). Males exhibited no association between consultation frequency and age. The main reasons for consultation were pregnancy/contraception (15.8%) and infection (15.7%). Alert symptoms were uncommon, (reported in 4.0% of all consultations; 276 alert symptoms in 179 patients), and were not associated with age or sex. The most common alert symptoms were unexplained pain (34.8%), unexplained fatigue (14.5%), and lumps (13.4%). Two benign tumours were detected.

Conclusion

A high proportion of teenagers and young adults consult their GP. Alert symptoms are uncommon and generally occur in isolation. More research is required to confirm these findings in a larger cohort and to examine how GPs respond to such alert symptoms.  相似文献   
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Familial amyloidotic polyneuropathy (FAP) is a monogenic disease caused by mutations in the transthyretin ( TTR ) gene. The phenotype of the most common TTR mutation, V30M, varies within and between populations. Oxidative stress and protein misfolding are cellular processes involved in the development of FAP. Because the mitochondria are important for both these processes, we investigated if mitochondrial haplogroups are related to age at onset of the disease in Swedish and French FAP patients. Mitochondrial haplogroup analysis was performed on 25 early-onset (below 40 years) and 29 late-onset (above 51 years) Swedish FAP patients. DNA from 249 Swedish individuals served as controls. In addition, 6 early-onset and 17 late-onset French FAP patients were examined with 25 French controls. The haplogroup distribution among late-onset Swedish and French cases was similar to that found in the general populations, whereas among early-onset cases a different haplogroup distribution was seen. The relatively rare haplogroup K was significantly more common among early-onset cases. Our findings substantiate the suggestion that a genetic component, still to be found, affecting mitochondrial function has an impact on the amyloid generating process in transthyretin amyloidosis.  相似文献   
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Objective To study the abortifacient activity of aqueous extract of Senna alata leaves in female Wistar rats.Methods Pregnant rats weighing 143.65 ± 13.11 g were completely randomized into 5 groups(A-E).Rats in group A(negative control) were orally administered,once daily with 0.5 ml of distilled water on days 10-18 post-coitum while those in groups B,C,D,and E were treated exactly like the negative control except they received the same volume containing 2.85 mg/kg body weight of mifepristone(group B,reference drug),250,500 and 1 000 mg/kg body weight of the extract respectively(groups C-E).Results Phytochemical screening of the extract showed positive results for saponins(1.22%),flavonoids(1.06%),cardiac glycosides(0.20%),cardenolides and dienolides(0.18%),phenolics(0.44%) and alkaloids(0.52%).Respiratory distress,salivation,diarrhoea,changes in the appearance of hair as well as maternal mortality were not observed at any time during the exposure period except in the mifepristone-treated animals where there was episode of diarrhoea and tiredness.The extract significantly reduced(P〈0.05) the number of life foetus,weight and survival ratio of the foetus,numbers of implantations and Corpora lutea,implantation index,progesterone,prolactin,estradiol,follicle stimulating and luteinizing hormones whereas the number of dead foetus,number and percentage of rats that aborted,percentage vaginal opening,resorption index,pre-and post-implantation losses increased significantly.In addition,mifepristone-treated animals produced resorption index that compared well with the distilled water control.There was also no dead or life foetus and serum progesterone concentration was increased in the animals treated with mifepristone.All cases of abortion were accompanied with vaginal bleeding.Although,the final weight of the rats increased significantly,the feed and water intake were not significantly altered in all the treatment groups.The weight of the uterus,uterine-body weight ratio,length of the right uterus horn and uterine cholesterol decreased significantly in all the treatment groups.The uterine alkaline phosphatase activity and glucose concentration increased in only the extract-treated animals whereas mifepristone decreased the uterine alkaline phosphatase activity and glucose content of the animals.Conclusion This study has provided evidence to the age-long claim of S.alata leaves in "washing the uterus".The abortifacient properties were most pronounced at 500 and 1 000 mg/kg body weight of the extract and were similar to the animals treated with 2.85 mg/kg body weight of mifepristone.Hormonal influence,changes in implantation site,estrogenicity and uterogenicity are suggested as possible mechanism of abortifacient activity of aqueous extract of S.alata leaves.Overall,the extract may be used as an abortifacient especially at 500 and 1 000 mg/kg body weight and therefore not safe for consumption as oral remedy during pregnancy.  相似文献   
55.
Avian influenza viruses of the H9 subtype cause significant losses to poultry production in endemic regions of Asia, Africa and the Middle East and pose a risk to human health. The availability of reliable and updated diagnostic tools for H9 surveillance is thus paramount to ensure the prompt identification of this subtype. The genetic variability of H9 represents a challenge for molecular-based diagnostic methods and was the cause for suboptimal detection and false negatives during routine diagnostic monitoring. Starting from a dataset of sequences related to viruses of different origins and clades (Y439, Y280, G1), a bioinformatics workflow was optimized to extract relevant sequence data preparatory for oligonucleotides design. Analytical and diagnostic performances were assessed according to the OIE standards. To facilitate assay deployment, amplification conditions were optimized with different nucleic extraction systems and amplification kits. Performance of the new real-time RT-PCR was also evaluated in comparison to existing H9-detection methods, highlighting a significant improvement of sensitivity and inclusivity, in particular for G1 viruses. Data obtained suggest that the new assay has the potential to be employed under different settings and geographic areas for a sensitive detection of H9 viruses.  相似文献   
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A thermostable nuclease homologue (NucM) in an animal-associated divergent clade of Staphylococcus aureus in sub-Saharan Africa has a highly divergent nucleotide sequence compared to those of the classical nuc1 and nuc2 genes of S. aureus. Its deduced amino acid sequences, tertiary structures, and nuclease activities, however, are similar.  相似文献   
59.
BackgroundCholera, a severe acute watery diarrhea caused by Vibrio cholerae is endemic in Nigeria with most cases occurring in the rural areas. In South West Nigeria, some individuals resort to alternative treatments such as Ogi-tutu, Psidium guajava and Vernonia amygdalina during infections. The effectiveness of these alternatives in the prevention and treatment of V. cholerae infection requires experimental investigation.ObjectiveThis study was designed to investigate the ameliorative effects of Ogi-tutu, Vernonia amygdalina and Psidium guajava on intestinal histopathology of experimental mice infected with V. cholerae.MethodsPreliminary investigation of in vitro vibriocidal activities of these alternatives were carried out using agar cup diffusion assay. For ameliorative effects, adult mice were inoculated with 100 µl (106 cells) of Vibrio cholerae and dosed at 0 h (immediate prevention) and 4 h (treatment of infection) and their intestines were histopathologically evaluated.ResultsThe histopathological changes were the same irrespective of the treated groups, but the lesions varied in extent and severity. The ameliorative effects in decreasing order were V. amygdalina > P. guajava > Ogi-tutu.ConclusionV. amygdalina gave the best ameliorative effects in the prevention and treatment of V. cholerae infection.  相似文献   
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