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991.

Background  

Analysis of the chromosomal background upon which a mutation occurs can be used to reconstruct the origins of specific disease-causing mutations. The relatively common BRCA1 mutation, 1135insA, has been previously identified as a Norwegian founder mutation. We performed haplotype analysis of individuals from breast and ovarian cancer families from four different ethnic backgrounds who had been identified as carriers of the BRCA1: 1135insA mutation.  相似文献   
992.
研究了6种氯代萘磺酰胺衍生物对细菌脂多糖(LPS)诱导经卡西霉素A23187体外激活的巨噬细胞分泌肿瘤坏死因子(TNF)作用的影响。表明:将氯代萘磺酰胺的氨基接以亲水性不同长度碳链的胺基,所得衍生物可明显抑制LPS诱生TNF的作用;接以疏水性烷基,则可明显增强亚适剂量的LPS诱生TNF的作用,且碳链长度对化合物的作用强度有一定的影响。  相似文献   
993.
Summary— Early investigation of protein binding of a new drug is mandatory. The following questions have to be answered: is unbound fraction constant over tested concentrations? Which proteins are involved? What are the binding parameters? Can the drug compete with other therapeutic agents for the binding sites or in other words can drug displacements be predicted? What is the interindividual variability in protein binding? Is the binding stereoselective? All this information is necessary in predicting the pharmacokinetic behaviour of the drug and in assisting in the design of future pharmacokinetic protocols in phases II and III. The use of free drug concentration should also be considered when comparing the bioavailability of regular vs sustained release dosage forms of drugs exhibiting concentration-dependent binding and when studying concentration-effect relationships.  相似文献   
994.
Abnormal membrane physical properties of red cells in McLeod syndrome   总被引:1,自引:0,他引:1  
McLeod red cells (RBCs) lack Kx antigens and have weak expression of the Kell antigens. Individuals who carry the McLeod phenotype have acanthocytic RBCs and a compensated hemolytic state. To elucidate the role of the protein on which the Kx antigens reside in maintaining membrane deformability, the rheologic properties of McLeod RBCs were determined by ektacytometry. RBCs were obtained from normal individuals and from four patients with McLeod syndrome. Osmotic gradient deformability profiles of McLeod RBCs showed decreased whole cell deformability. Resealed ghosts from McLeod RBCs also showed decreased deformability, partly because of the decreased cell surface area and partly because of an intrinsic membrane stiffness in this syndrome. For the measurement of membrane mechanical stability, resealed ghosts were subjected to constant high shear stress in the ektacytomer, and deformability was recorded continuously as the deformable ghosts fragmented into rigid spherical vesicles. Membranes from McLeod RBCs showed a noticeable increase in mechanical stability. Acquired causes of acanthocytosis, such as liver disease, did not cause the rheologic abnormalities observed in McLeod cells. Other abnormalities noted in McLeod RBCs were decreased RBC potassium content and an increased number of dense RBCs, as determined by centrifugation on a discontinuous density gradient. The data indicate that McLeod RBCs are rigid and have decreased surface area and that their membranes are intrinsically rigid with increased mechanical stability. These abnormalities may account for the reduced RBC survival observed in McLeod syndrome. The protein that carries the Kx surface antigen seems to be required for the maintenance of the normal physical function of RBC skeletal proteins.  相似文献   
995.

Background

To control avian coccidiosis with drug-independent strategy effectively and safely, multivalent hyperimmune egg yolk immunoglobulin (IgY) was prepared and its ability to protect against Eimeria tenella infection was evaluated.

Methods

Hens were orally immunized with live oocysts of 5 species of Eimeria for six times, antibody titers in serum and yolk were monitored by indirect enzyme-linked immunosorbent assay. The specific IgY was isolated, purified and lyophilized. IgY powder was orally administrated as dietary supplement in newly hatched chicks at various dosages. Birds were orally challenged with 10000 sporulated oocysts of E. tenella at 10 days of age, weighed and killed at 8 days post challenge, and the protective effect was assessed.

Results

The averge yeid of IgY was 9.2 mg/ml yolk, the antibody titer of IgY reached to 1:163840 per mg with the purity up to 98%. Chickens fed IgY resulted in reduced mortality, increased body weight gain (BWG), reduced oocyst shedding, reduced caecal lesion score and increased anti-coccidial index. In terms of BWG and caecal lesion, IgY significantly enhanced the resistance of bird at ≥ 0.05% of IgY in the diet when compared with the challenged control group (P<0.05). No significant difference was observed at dosage ≥ 0.5% and 1.0% when BWG and caecal lesion were compared with the sodium salinomycin control group, respectively (P>0.05).

Conclusion

Supplementing newly hatched chicks with Eimeria-specific IgY represents a promising strategy to prevent avian coccidiosis.  相似文献   
996.
The safety of hydroquinone   总被引:2,自引:0,他引:2  
Hydroquinone is one of the most effective molecules for the treatment of hyperpigmentary disorders, with over 40 years of efficacy and safety data. Concerns over its safety have been raised because of the fact that it is a derivative of benzene and because of the long-term side-effects observed with cosmetic products containing high concentrations of hydroquinone. However, despite 40-50 years use of hydroquinone for medical conditions, there has not been a single documented case of either a cutaneous or internal malignancy associated with this drug. This article reviews the evidence for the safety of hydroquinone in the treatment of hyperpigmentation conditions.  相似文献   
997.

Background

Patients with ectopic pregnancy (EP) and low serum hCG concentrations and women with a pregnancy of unknown location (PUL) and plateauing serum hCG levels are commonly treated with systemic methotrexate (MTX). However, there is no evidence that treatment in these particular subgroups of women is necessary as many of these early EPs may resolve spontaneously. The aim of this study is whether expectant management in women with EP or PUL and with low but plateauing serum hCG concentrations is an alternative to MTX treatment in terms of treatment success, future pregnancy, health related quality of life and costs.

Methods/Design

A multicentre randomised controlled trial in The Netherlands. Hemodynamically stable patients with an EP visible on transvaginal ultrasound and a plateauing serum hCG concentration < 1,500 IU/L or with a persisting PUL with plateauing serum hCG concentrations < 2,000 IU/L are eligible for the trial. Patients with a viable EP, signs of tubal rupture/abdominal bleeding, or a contra-indication for MTX will not be included. Expectant management is compared with systemic MTX in a single dose intramuscular regimen (1 mg/kg) in an outpatient setting. Serum hCG levels are monitored weekly; in case of inadequately declining, systemic MTX is installed or continued. In case of hemodynamic instability and/or signs of tubal rupture, surgery is performed. The primary outcome measure is an uneventful decline of serum hCG to an undetectable level by the initial intervention. Secondary outcomes are (re)interventions (additional systemic MTX injections and/or surgery), treatment complications, health related quality of life, financial costs, and future fertility. Analysis is performed according to the intention to treat principle. Quality of life is assessed by questionnaires before and at three time points after randomisation. Costs are expressed as direct costs with data on costs and used resources in the participating centres. Fertility is assessed by questionnaires after 6, 12, 18 and 24 months. Patients' preferences will be assessed using a discrete choice experiment.

Discussion

This trial will provide guidance on the present management dilemmas in women with EPs and PULs with low and plateauing serum hCG concentrations.

Trial registration

Current Controlled Trials ISRCTN 48210491  相似文献   
998.
Parasitic worms of the genus Schistosoma excrete relatively large amounts of immunogenic glycoproteins (circulating cathodic antigen [CCA]) that contain polysaccharide side chains with the trisaccharide Lewis-x (L(ex)) as a repeating unit. These carbohydrates evoke high titers of specific IgM antibodies that cross-react with the repeating L(ex) units on the surface of granulocytes. Consequently this might lead, in the presence of complement, to lysis of the granulocytes. In the present study, this hypothesis was investigated using anti-CCA mouse monoclonal antibodies (MoAbs) and polyclonal antibodies purified from sera of infected humans. By flow cytometry, it was demonstrated that the mouse MoAbs directed against CCA strongly recognized the granulocytes. It could also be shown that these MoAbs, as well as anti- CCA IgM antibodies purified from infected human sera, caused lysis of granulocytes in a complement-dependent cytotoxicity assay. Sera from healthy controls or from patients with other helminth infections resulted in negligible granulocytotoxicity. These in vitro observed phenomena may explain the mild to moderate neutropenia that occurs in schistosomiasis patients.  相似文献   
999.
1000.
Regurgitation in infants is a common problem. Recent issues, such as the increased risk of sudden infant death in the prone sleeping position, the finding of persisting occult gastro-oesophageal reflux with feed thickeners, and the increasing awareness of the cost-benefit ratio of medications may challenge the currently recommended management approach. A round table was organized to elaborate on the impact of (i) the pro supine sleeping campaigns in relation to sudden infant death and (ii) advancement in medical treatment on therapeutic strategies in regurgitating infants. The participants were opinion leaders from Europe and North America (Belgium, Canada, France, UK, Italy, Switzerland and The Netherlands). The importance of parental reassurance is stressed. As a consequence of the supine sleeping campaigns aiming to decrease the incidence of sudden infant death syndrome, the "prone elevated sleeping position" is no longer advised as a first-line therapeutic approach, although it is still recommended in "complicated reflux". It is emphasized that milk thickeners are an adequate therapeutic tool for regurgitation, but not in reflux disease. According to the literature, the efficacy of (alginate-) antacids, although very popular in some countries, is questionable. These recommendations will be of interest to first-line paediatricians, since about 40% of their patients, according to the literature, present because of regurgitation.  相似文献   
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