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911.

Objective

To evaluate the effect of a physical activity programme in the aquatic environment with immersion up to the neck, of six weeks duration, on haemodynamic constants in pregnant women.

Methods

A six-week physical activity programme in the aquatic environment was carried out with a total of 46 pregnant women, who were distributed into an experimental group (n = 18), which participated in the programme, and a control group (n = 28), which followed routine care. In both groups different haemodynamic measurements were evaluated before and after the program.

Results

At the beginning of the programme the mean systolic blood pressure was similar between groups, but diastolic blood pressure was slightly higher in the experimental group. When the measurements at the last session were compared, arterial pressures (systolic, diastolic and mean) were significantly higher in the control group (p <.050). Similarly, the initial plasma volume values did not differ between groups, but after the intervention, the control group women showed a higher mean (p <.010). The fraction of sodium excretion (FENa) increased significantly in the experimental group, after the programme, with a mean three times higher (p <.050). Aldosterone plasma levels did not show significant differences between the groups in the different measurements.

Conclusion

A programme of swimming and immersion exercises in pregnant women contributes to hydrosaline balance, preventing an excessive increase in usual plasma volume during pregnancy and in the activity of the renin-aldosterone axis.  相似文献   
912.
The present work shows the synthesis of a new type of catanionic surfactant, ModCD14–BHD, which involves an anionic amphiphilic cyclodextrin and the cationic benzyl-n-hexadecyldimethylammonium (BHD). It is obtained from the simple association of the cationic surfactant benzyl-n-hexadecyldimethylammonium chloride (BHDC) and β-cyclodextrin (β-CD) monosubstituted with an alkenyl succinate group (Mod-β-CD14). ModCD14–BHD form unilamellar vesicles spontaneously in water, while the individual components (BHDC and Mod-β-CD14) do not. The vesicles were character-ized by dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and 1H NMR techniques. We suggest that the formation of an inclusion complex between some of the cyclodextrins units and the long hydrocarbon moiety of the cationic surfactant play a crucial role in the vesicles formation. Besides, some or the cavities are available to interact with an external guest. We think that the new surfactant molecule has properties that may lead to important applications in biomedical and pharmaceutical sciences.

Catanionic vesicles containing an anionic β-cyclodextrins derivative and a cationic surfactant.  相似文献   
913.
914.
Abstract

The effect of cisplatinum as a potential radiosensitizer in brain tumors is controversial. We examined the effect of the combination of cisplatinum with radiation compared to radiation alone in rabbits' brain. All rabbits were irradiated and cisplatinum was injected intravenously into part of them. Therapeutic doses of cisplatinum and irradiation were given. The rabbits were euthanised at different intervals according to protocol. The general clinical and neurological condition of the rabbits was unaffected\ and histopathological examination of the rabbit's brain was normal. The purpose of this study was to establish the effect of cisplatinum followed by cranial irradiation in therapeutic doses to the normal rabbit's brain. [Neurol Res 1996; 18: 454-456]  相似文献   
915.

Background

To compile an evaluation system (score) for post-treatment outcomes of midclavicular fractures, 172 patients were studied on average 15 months post-injury. As a control group 45?healthy volunteers were examined. The most relevant elements were filtered out for use in a new classification system, the Clavicle Score (CS).

Methods

The CS is based on a system of three partnered objective/subjective items as well as radiographic assessment of fracture healing. For the partnered items, subjective responses with the most significant correlation to the specific objective parameters were selected. Total score cutoff values (very good, good, moderate, poor) were established to keep interpretation simple. To validate the system, linear regression analysis was performed comparing the CS to two established assessment systems (Constant Score and the DASH Score).

Ergebnisse

The correlation coefficients R=0.756 (Constant) and R=0.687 indicated that the conclusions were comparable and therefore valid. The reliability coefficient Cronbach??s alpha was calculated at 0.8241, indicating high reliability.

Conclusion

The CS is a simple, valid and reliable instrument to assess outcomes post-midclavicular fracture.  相似文献   
916.
The role of sialylation in kidney biology is not fully understood. The synthesis of sialoglycoconjugates, which form the outermost structures of animal cells, requires CMP-sialic acid, which is a product of the nuclear enzyme CMAS. We used a knock-in strategy to create a mouse with point mutations in the canonical nuclear localization signal of CMAS, which relocated the enzyme to the cytoplasm of transfected cells without affecting its activity. Although insufficient to prevent nuclear entry in mice, the mutation led to a drastically reduced concentration of nuclear-expressed enzyme. Mice homozygous for the mutation died from kidney failure within 72 hours after birth. The Cmas(nls) mouse exhibited podocyte foot process effacement, absence of slit diaphragms, and massive proteinuria, recapitulating features of nephrin-knockout mice and of patients with Finnish-type congenital nephrotic syndrome. Although the Cmas(nls) mouse displayed normal sialylation in all organs including kidney, a critical shortage of CMP-sialic acid prevented sialylation of nephrin and podocalyxin in the maturing podocyte where it is required during the formation of foot processes. Accordingly, the sialylation defects progressed with time and paralleled the morphologic changes. In summary, sialylation is critical during the development of the glomerular filtration barrier and required for the proper function of nephrin. Whether altered sialylation impairs nephrin function in human disease requires further study.  相似文献   
917.
918.
919.
111In-labeled granulocytes were used to study the effects of histocompatibility factors on the migration of transfused granulocytes to infected sites. Fourteen alloimmunized and 20 nonalloimmunized patients received approximately 10(8) 111In-labeled granulocytes from ABO-compatible, non-HLA-matched donors, and scans were performed over known infected sites. All 14 alloimmunized patients had lymphocytotoxic antibody (LCTAb) and required HLA-matched platelet transfusions. Of the nonalloimmunized patients, 20/20 had positive scans at sites of infection. None of the 20 had LCTAb, 0/17 had a positive lymphocytotoxic crossmatch (LCTXM) with the donor, and 3/18 had a positive leukoagglutinin crossmatch (LAXM). Thus, histocompatibility testing was not found to be important in nonalloimmunized patients. In contrast, only 3/14 alloimmunized patients had positive scans at sites of infection (p = 0.00001 compared to nonalloimmunized patients). One of 3 had a positive LCTXM and 2/3 had a positive LAXM. Of the alloimmunized patients, 10/11 with negative scans had a positive LCTXM and 8/11 had a positive LAXM. Labeled granulocytes failed to reach sites of infection in 11/14 (78%) alloimmunized patients, demonstrating that histocompatibility factors can be of major importance in affecting the outcome of granulocyte transfusions. Granulocytes from random donors are unlikely to be effective in alloimmunized patients. The lack of an adequate crossmatching technique is a major problem limiting the ability to provide granulocyte transfusions for alloimmunized patients.  相似文献   
920.
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