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61.
14-3-3 sigma:, a target gene of the p53 tumour suppressor protein, has been shown to regulate the cell cycle at the G2/M checkpoint. Recent studies have demonstrated that 14-3-3 sigma is downregulated by hypermethylation of the CpG island in several types of cancer. In this study, we investigated the expression and methylation status of 14-3-3 sigma in human salivary gland adenoid cystic carcinoma (ACC) and mucoepidermoid carcinoma (MEC). Immunohistochemical analysis revealed that the positive expression rate of 14-3-3 sigma in ACC (one out of 14) was markedly lower than that in MEC (ten out of 10). Since most of the ACCs carried the wild-type p53 protein, downregulation of 14-3-3 sigma in ACC may not be due to the dysfunction of p53 pathway. Microdissection-methylation-specific PCR revealed that frequent hypermethylation of the 14-3-3 sigma gene was observed in ACC when compared to that in MEC. In cultured-ACC cells, we confirmed the downregulation of 14-3-3 sigma via hemimethylation of the gene by sequencing analysis after sodium bisulphite treatment. Furthermore, re-expression of 14-3-3 sigma in the ACC cells was induced by the treatment with DNA demethylating agent, 5-aza-2'-deoxycytidine. Irradiation apparently induced the enhanced expression of 14-3-3 sigma and G2/M arrest in normal salivary gland cells; however, in the ACC cells, neither induction of 14-3-3 sigma nor G2/M arrest was induced by irradiation. These results suggest that downregulation of 14-3-3 sigma might play critical roles in the neoplastic development and radiosensitivity of ACC.  相似文献   
62.
The effect of carbofuran insecticide on certain metabolites and enzymes of protein and carbohydrate metabolism was evaluated in liver and muscle tissues of the freshwater fish, Clarias batrachus during exposure and following cessation of exposure. Thirty-six fish were exposed to 7.66mg of carbofuran/l for 6 days. After 6 days, 18 fish were transferred into carbofuran-free water for 6 days (recovery period) in order to study the recovery response. Eighteen fish were kept in clean water as controls. Liver and muscle tissues were isolated from exposed, recovery and control fish at the end of 1, 3 and 6 days in each condition, and used for the estimation of protein, amino acids, ammonia, glycogen, aminotransaminases, glycogen phosphorylase (a and ab) and glutamate dehydrogenase. Total protein showed a delayed decrease in liver and muscle tissues but recovered by the end of the recovery period. Free amino acid content was affected little in liver, but was elevated in muscle, and ammonia levels were elevated in both tissues throughout the exposure period, and ammonia levels in liver remained elevated during recovery. Glycogen content of liver declined substantially, and rebounded after transfer of fish into clean water. The activity levels of alanine aminotransaminase, aspartate aminotransaminase, glutamate dehydrogenase and glycogen phosphorylase a were found to increase in both tissues during the exposure period. The glycogen phosphorylase ab activity in liver was suppressed on exposure to carbofuran. The enzymes exhibited different recovery pattern in liver and muscle tissues of C. batrachus. The patterns of effect of carbofuran on intermediary metabolism suggest avenues to determine the mechanisms by which such effects occur.  相似文献   
63.
Prevalence of endometriosis in malignant epithelial ovary tumours   总被引:7,自引:0,他引:7  
OBJECTIVE: To determine the prevalence of ovarian endometriosis in malignant epithelial ovarian tumours. STUDY DESIGN: A retrospective analysis of 160 malignant and 23 borderline ovarian tumours during the period 1995-2001. RESULTS: Fourteen (7.7%) of the tumours contained endometriosis. This affected 22% of the endometrioid and 10.8% of the mixed adenocarcinomas. The mean age of the ovarian endometriosis patients was 43+/-13 range 26-70 years. The incidence in borderline tumours 13% (3/23) was higher than that in ovarian cancer 6.9% (11/160) (P>0.05). Eight (57%) of cases were classified as atypical and six (43%) as typical endometriosis. Nine cases were FIGO (International Federation of Gynaecology and Obstetrics) stage I and 5 stage III. CONCLUSIONS: Both malignant and borderline ovarian tumours are associated with ovarian endometriosis. In addition, atypical endometriosis was found associated with endometrioid and mixed epithelial ovarian tumours.  相似文献   
64.
Zinc in CSF of patients with febrile convulsion   总被引:2,自引:0,他引:2  
OBJECTIVE: This prospective study was carried out from July-December 1999 to see the status of zinc in CSF of children with febrile convulsion and to compare this to that of control. METHODS: Forty-two cases of febrile convulsion and 30 controls (fever without convulsion) were enrolled into the study. CSF zinc was estimated by atomic absorption spectrophotometry (AAS) in Atomic Energy Center, Dhaka and compared between the two groups. RESULTS: The mean zinc level in CSF in the study sample was 40.19mgm/L and that in control was 74.98mgm/L. This difference was statistically significant (p<0.001). CONCLUSION: The study concludes that a significantly lower of zinc exists in CSF of children with febrile. However no relationship was found between CSF zinc status with age, sex, degree & duration of fever and time of lumbar puncture after convulsion.  相似文献   
65.
Bioactive glasses of the system SiO2-Na2O-CaO-P2O5 have been prepared by the normal melting and annealing technique. The elastic moduli, attenuation, Vickers hardness, fracture toughness and fracture surface energy have been obtained using the known method at room temperature. The temperature dependence of elastic moduli and attenuation measurements have been extended over a wide range of temperature from 150 to 500 K. The SiO2 content dependence of velocities, attenuation, elastic moduli, and other parameters show an interesting observation at 45 wt% of SiO2 by exhibiting an anomalous behaviour. A linear relation is developed for Tg, which explores the influence of Na2O on SiO2-Na2O-CaO-P2O5 bioactive glasses. The measured hardness, fracture toughness and fracture surface energy show a linear relation with Young's modulus. It is also interesting to note that the observed results are functions of polymerisation and the number of non-bridging oxygens (NBO) prevailing in the network with change in SiO2 content. The temperature dependence of velocities, attenuation and elastic moduli show the existence of softening in the glass network structure as temperature increases.  相似文献   
66.
Among 42 extracts, prepared from 14 medicinal plants used in Vietnamese traditional medicine to treat malaria, 24 were found to have antiplasmodial activity by inhibiting the growth of the chloroquine-resistant Plasmodium falciparum strain FCR-3 with EC(50) values less than 10 microg/ml. Each medicinal plant possessed at least one active extract. The methanol extract of Coscinium fenestratum had the strongest antiplasmodial activity with EC(50) value of 0.5 microg/ml. Activity-guided fractionation led to identification of berberine as the major active constituent.  相似文献   
67.
68.
The study focuses on children less than 5 years old and explores the epidemiological profile and correlates of drowning as a challenge to child survival in Bangladesh. Two data sources from Bangladesh, a cohort of 8,070 children followed for 2 years in a rural area and a nation-wide survey conducted in 1996-97 have been used. In addition, a systematic review of the literature has been conducted spanning the past two decades for analysis of drowning in children. Seventy drowning deaths were reported in the cohort and 726 deaths were reported in the national survey. Verbal autopsy and semi-structured interviews were conducted on all deaths. Drowning accounted for 43% of deaths in the cohort and 20% of deaths in 1-4-year-old children in the national survey. Most drowning deaths were in 12-23 month old children from falling into ditches and ponds. Communities provided valuable insights on possible interventions to reduce deaths due to drowning. Drowning is a newly recognized challenge for Bangladesh. Considerable research and programmatic work is required to understand the nature of the problem and develop appropriate interventions. This paper calls on aid agencies to create opportunities for drowning research and action in their work plans for the country.  相似文献   
69.
Fifty consecutive younger patients (< or = 40 years) with coronary artery disease, who underwent coronary angiography in National Institute of Cardiovascular Diseases were evaluated clinically and coronary risk factors were analyzed and compared with those of fifty older patients with coronary artery disease. Mean age of younger and older patients were 37.31 and 54.58 years respectively and myocardial infarction was the most common presenting complain in both the groups. Smoking and family history of premature coronary artery disease were more common in younger patients but the older patients were more diabetic and hypertensive. Central obesity and dyslipidemia did not vary between the two groups. Fifty percent of younger patients had one or two modifiable risk factors where sixty four percent of older patients had three or more modifiable risk factors. Forty four percent younger patients had hypercholesterolemia but a majority of patients had either isolated hypertriglyciredemia or decrease high density lipoprotein cholesterol or both with normal total cholesterol level but the total cholesterol and high density lipoprotein cholesterol index were more than 4.5. Younger patients had more number of normal coronary or single vessel diseases but older group had more number of triple vessel diseases. So the higher incidence of non-insulin dependent diabetes mellitus with central obesity suggesting insulin resistance along with unique profile of dyslipidemia, higher incidence of smoking and familial predisposition of premature coronary artery disease may be responsible for higher incidence of coronary artery disease at a premature younger age in this population.  相似文献   
70.
Grover P  Banu BS  Devi KD  Begum S 《Toxicology》2001,167(3):191-197
DNA damage induced by Mercuric chloride (HgCl2) in leucocytes of Wistar albino male rats has been studied in vivo. The comet assay or the alkaline single cell gel electrophoresis (SCGE) assay was used to measure the DNA damage. The rats were administered orally with doses ranging from 0.0054, 0.0108, 0.0216, 0.0432 to 0.0864 mg/kg body weight (b.wt.) of HgCl2. The assay was performed on whole blood at 24, 48, 72 h, 1st and 2nd week. The reason leucocytes were used was to reflect biomarker studies in humans. A significant increase in mean comet tail length indicating DNA damage was observed at all time intervals with HgCl2 except in 2nd week post treatment when compared to controls. The mean comet tail length revealed a clear dose dependent increase from 0.0054 to 0.0432 mg/kg b.wt. A maximum increase in mean comet tail length was observed at 0.0432 mg/kg b.wt. 24 h after treatment. From 48 h post treatment, the mean comet tail lengths of all the doses gradually decreased and by week 2 of post treatment, they had approached control levels, pointing to repair of the damaged DNA. These findings suggest that the comet assay is a highly sensitive technique to study DNA damage caused by metals.  相似文献   
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