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61.
Although Cholesteryl Ester Transfer Protein (CETP) mediates the transfer of cholesteryl esters and triglycerides between lipoprotein particles and thus plays a crucial role in reverse cholesterol transport, the association of variations in the CETP gene with acute myocardial infarction (MI) remains unclear. In this study we examined whether common genetic variation in the CETP gene is related to early‐onset non‐fatal MI risk in a population‐based case‐control study from western Washington State. Genotyping for the CETP ?2708 G/A, ?971 A/G, ?629 A/C, Intron‐I TaqI G/A and exon‐14 A/G (I405V) SNPs was performed in 578 cases with first acute non‐fatal MI and in 666 demographically similar controls, free of clinical cardiovascular disease, identified randomly from the community. In‐person interviews and non‐fasting blood specimens provided data on coronary heart disease risk factors. In men, there was little evidence for an association between single SNPs and MI risk, but in women the age‐ and race‐adjusted OR was found to be significant in 4 out of the 5 CETP single variants. Haplotype analysis revealed two haplotypes associated with MI risk among men. As compared to men homozygous for the most common haplotype D (?2708 G, ?971 G, ?629 C, TaqI G and exon‐14 A), the fully‐adjusted multiplicative model identified haplotype G (?2708 G, ?971 A, ?629 A, TaqI G and exon‐14 G) was associated with a 4.0‐6.0‐fold increased risk of MI for each additional copy; [95%CI 2.4–14.8] and haplotype B (?2708 G, ?971 G, ?629 A, TaqI A and exon‐14 A) showed a significant decreased risk for early onset MI [OR = 0.18; 95%CI 0.04 – 0.75]. An evolutionary‐based haplotype analysis indicated that the two haplotypes associated with the MI risk are most evolutionarily divergent from the other haplotypes. Variation at the CETP gene locus is associated with the risk of early‐onset non‐fatal MI. This association was found to be independent of HDL‐C levels. These data and the sex‐specific findings require confirmation in other populations.  相似文献   
62.
The current study analyzes the rearrangement pattern of immunoglobulin H (IgH), T-cell receptor (TCR)-gamma, and TCR-beta genes in a group of 80 non-Hodgkin's lymphomas (NHL) of different histologic subtypes (43 B-cell and 37 T-cell types). The sensitivity and specificity provided by polymerase chain reaction amplification of these loci are evaluated. The association between the proliferation index and the presence of the so-called "aberrant" or "dual" rearrangements is also considered. Ninety-one percent of B-cell NHL showed IgH gene monoclonality, and 21% also exhibited a monoclonal pattern in one of the TCR genes. Among T-cell NHL, the sensitivity of the study was 65% for the TCR-gamma gene and 46% for the TCR-beta gene. The total sensitivity was 76%, amplifying both loci. IgH gene aberrant rearrangements were observed in 16% of T-cell neoplasms. A substantial percentage of dual rearrangements were detected in precursor and mature B- and T-cell NHL. B-cell NHL showed a tendency toward higher values of proliferation when aberrant rearrangements were present; however, this trend was not significant. Furthermore, in the case of T-cell NHL there was a significant negative association between these two variables.  相似文献   
63.
Primary myeloid sarcoma of the testicle with t(15;17)   总被引:1,自引:0,他引:1  
The first case of acute promyelocytic leukemia presenting as a solitary testicular mass (myeloid sarcoma) that relapsed in the contralateral testicle is described. The neoplastic cells strongly expressed chloroacetate esterase, myeloperoxidase, CD33, CD43, and weakly, CD117. The presence of many azurophil granules and Auer rods was detected by electron microscopy. Translocation (15;17)(q22;q21.1) was revealed by cytogenetics and was verified by fluorescence in situ hybridization. Contralateral testicle is a favorite site for recurrence in a subset of testicular myeloid sarcomas. Subclassification of all cases of myeloid sarcoma ought to be attempted.  相似文献   
64.
Voluntary and forced exercise decrease morbidity and mortality in laboratory animals. Caloric restriction has similar effects on health and unique benefits on life span. Nonetheless, in most experiments, animals do not have access to physical activity and are fed ad libitum (AL). We hypothesized that with regular access to either unlimited running wheel exercise (EX) or limited physical activity (PA), key biomarkers of health would be enhanced enough to counter some consequences of a sedentary AL lifestyle. This 16-month study compared body weight, tumor number and size, tissue lesions, oxidative stress, and reactive stress in (1) sedentary animals with no access to physical activity (SED); (2) animals with access to hour-long, twice weekly activity in a large box (PA); and (3) animals with access every other day to a running wheel (EX). At the end of the study, EX body weight was 8-9% lower than PA and SED. In addition, EX had no kidney lesions versus 50% in PA and SED, and had smaller tumor size (10+/-2 vs. 14+/-4 and 30+/-4 mm). Exhaustive exercise lowered glutathione/oxidized glutathione ratio in EX and PA, but in SED, the ratio was depressed even in resting animals. In all treatments, prolactin (PRL) levels were lower in resting animals than in acutely exercised animals. In conclusion, EX had the most favorable health biomarkers while SED had the least. PA did not confer gross health benefits different than the SED group, but was biochemically more similar to EX animals.  相似文献   
65.
Results of four years' studies from a number of hospitals in Kenya have shown that nosocomial infections in burns units are due to Methicillin Resistant Staphylococcus aureus (MRSA). Through chromosomal DNA and plasmid DNA, the stain is highly resistant to sulphonamide ointment and other antibiotics. 90% of patients admitted in burns units get colonized or infected with MRSA. The strain prolongs the duration of patients in hospitals. The burns degenerate to second and third degree burns, thereby necessitating skin grafting. The environment has been found to be contaminated with this strain with some staff members having chronic throat infections. Minocycline was found to be effective in treating the infected staff members. Cleaning this environment with Sodium dichloroisocyanurate (precepts)/Sodium hypochlorite (JIK) reduced drastically the mechanical transmission of bacteria in the units. The duration of stay of the patient was reduced. This shows that MRSA which is spread in government and private hospitals can cheaply be controlled by the proper use of disinfectants, antiseptics, and use of effective antibiotics when necessary.  相似文献   
66.
Rare monogenic forms of Parkinson's disease (PD) are promoting our understanding of the molecular pathways involved in the common, non-Mendelian forms of the disease. Here, we focus on PARK7, an autosomal recessive form of early-onset parkinsonism caused by mutations in the DJ-1 gene. We first review the genetics of this form and the rapidly expanding knowledge about the structure and biochemical properties of the DJ-1 protein. We also discuss how DJ-1 dysfunction might lead to neurodegeneration, and the implications of this novel piece of information for the pathogenesis of the common PD forms. Although much work remains to be done to clarify the biology of DJ-1, its proposed activity as a molecular chaperone and/or as oxidative sensor appear intriguing in the light of the current theories on the pathogenesis of PD.  相似文献   
67.
68.
Antimicrobial susceptibility and frequency of occurrence of clinical blood isolates in Sfax-Tunisia (1993-1998). The choice of antimicrobial therapy for the treatment of bacteremia is often empirical and based on the knowledge of susceptibility profiles of the most common bacteria causing such infections. This study determines the bacterial etiology of bacteremic episodes and antimicrobial susceptibility patterns recorded at a teaching hospital, from January 1993 to December 1998. We collected 2979 strains responsible for bacteremia. Gram negative bacteria were predominant (60%). The organisms recovered most frequently were Staphylococcus aureus (18.9%), Escherichia coli (14.7%), Klebsiella pneumoniae (14%) and Pseudomonas aeruginosa (7.6%). The incidence of resistance to methicillin were 17.4% for Staphylococcus aureus and 26.8% for coagulase negative Staphylococcus. No resistance to glycopeptides was observed among the enterococci and staphylococci studied. 27.7% of enterobacteriaceae were resistant to third generation cephalosporins. Imipenem was the most active agent against gram negative bacteria. To carry out a surveillance of bacteremic episodes occurring at every hospital, it is necessary to provide valuable information which should be the basis for effective empiric therapy.  相似文献   
69.
The most important aspect of diminished ovarian reserve is the associated decline in reproductive potential. Assessment of ovarian reserve is mainly based on measurement of early follicular phase follicle stimulating hormone (FSH) concentration. The objective of this study was to report the identification of a group of 12 infertile women initially diagnosed as having unexplained or anovulatory infertility, who had a normal baseline hormonal profile and did not respond to repeated ovarian stimulation with gonadotrophins. All developed ovarian failure within a relatively short time span. Non-response to ovarian stimulation was defined by failure to achieve development of follicles >12 mm and failure to raise oestradiol concentration >350 pmol/l in two successive cycles of human menopausal gonadotrophin (HMG) doses of up to five ampoules per day for 5-8 days. Within a mean of 9 months following the failed attempts of ovarian stimulation the mean day 3 FSH concentrations rose from 5.4 +/- 2.7 IU/l to 53.5 +/- 19.7 IU/l. In these patients, day 3 FSH concentration failed to indicate the low ovarian reserve manifested only by lack of clinical response to treatment with gonadotrophins which was the first sign of impending ovarian failure. We conclude that women with normal early follicular phase serum FSH concentrations who do not respond to ovarian stimulation by HMG are at risk of developing ovarian failure within several months.   相似文献   
70.
The dose-response characteristics of dieldrin-mediated enhancementof liver tumour formation in CF-1 mice were analysed, usingexisting tumour data from chronic feeding studies at six levelsof continuous exposure, involving a total of > 1500 animals.The dose-response relationship can be expressed as: Dx x Tx= D0 x T0 = constant, where T0 = the median liver tumour inductionperiod in control CF-1 mice, Tx = the median liver tumour inductionperiod in dieldrin-treated mice at a dose level Dx, D0 = thebackground dose equivalent for the induction of ‘spontaneous’liver tumours, Dx = the sum of background dose (D0) and actualdieldrin dose (x). The relationship, which is a Druckrey equation(D x Tn = constant) where n = 1, indicates that: (i) the velocityof liver tumour development is proportional to the daily doselevel (Dx), (ii) the total tumourigenic dose is constant acrossall doses, (iii) the effects of dieldrin on the neo-plasticprocess in mouse liver are essentially irreversible and cumulative,and (iv) there is no evidence for a threshold level. However,when x «D0, the actual contribution of dieldrin to tumourformation is expected to be negligible.  相似文献   
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