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41.
Twelve patients with preasthma (PA) and 27 bronchial asthma (BA) patients were examined for the effect of magnesium sulphate aerosol on bronchial sensitivity and reactivity to acetylcholine (ACC) and graded physical exercise (GPE) as well as on bronchial patency recorded by general plethysmography and pneumotachography. Inhalation of the drug was established to exert no bronchodilatory action but reduced, as compared with placebo, nonspecific hyperreactivity of the bronchial tree and blocked the ACC induced increment of histamine in the exhaled air condensate. The data obtained allow bronchial smooth muscles and mast cells to be regarded as targets for magnesium sulphate. The drug properties discovered may serve a prerequisite for its use in the combined treatment of BA patients and those with PA.  相似文献   
42.
43.
In this article, we present evidence that sialic acid-containing surface components play a role in the regulation of erythropoiesis. A 1- hr exposure of mouse bone marrow cells to high concentrations of neuraminidase reduced erythroid colony formation. Coculture of 10(6) untreated thymocytes with neuraminidase-treated bone marrow cells restored erythroid colony growth. Neuraminidase-treated thymocytes retained their ability to suppress erythroid colony formation by untreated marrow cells, but lost their ability to enhance erythroid colony formation. Continuous exposure to low concentrations of neuraminidase enhanced erythroid bone marrow cell colony growth in response to a suboptimal dose of erythropoietin.  相似文献   
44.
Epileptic spasms were defined by the International League Against Epilepsy Task Force on Classification and Terminology in 2001 as a specific seizure type. Epileptic spasms without hypsarrhythmia have been described in some series of patients, occurring either in infancy or childhood. More prolonged epileptic spasms without hypsarrhythmia were previously defined as a different seizure type, and referred to as “tonic spasm seizures”. Here, we present a 5‐year‐old boy who started having epileptic spasms without hypsarrhythmia at 8 months of age, effectively treated with oxcarbazepine. With the withdrawal of medication, epileptic spasms returned. Video‐EEG monitoring revealed high‐voltage slow waves superimposed by low‐voltage fast activity, followed by an electrodecremental phase and a burst of asymmetric fast activity, time‐locked to clinical tonic spasm seizures. Brain MRI showed left temporal atrophy with temporal pole grey/white matter junction blurring and ictal PET‐CT showed left basal frontal hypermetabolism. Seizures were refractory to several AEDs and vigabatrin was introduced with seizure cessation. Despite efforts to classify epileptic spasms, these are still considered as part of the group of unknown seizure types. In some cases, a focal origin has been suggested, leading to the term “periodic spasms” and “focal spasms”. In this case, epileptic spasms without hypsarrhythmia, associated with tonic spasms, may be a variant of focal spasms and might be considered as an epileptic syndrome. [Published with video sequence]  相似文献   
45.
A macrophage-derived inhibitor of early hematopoietic progenitors (colony-forming unit-spleen, CFU-A) called stem cell inhibitor was found to be identical to macrophage inflammatory protein-1 alpha (MIP-1 alpha). We investigated the effect of MIP-1 alpha on the earliest stem cells that sustain long-term hematopoiesis in vivo in a competitive bone marrow repopulation assay. Because long-term reconstituting (LTR) stem cells are normally quiescent, an in vivo model was first developed in which they are triggered to cycle. A first 5-fluorouracil (5-FU) injection was used to eliminate later progenitors, causing the LTR stem cells, which are normally resistant to 5-FU, to enter the cell cycle and become sensitive to a second 5-FU injection administered 5 days later. Human MIP-1 alpha administered from day 0 to 7 was unable to prevent the depletion of the LTR stem cells by the second 5-FU treatment, as observed on day 7 in this model, suggesting that the LTR stem cells were not prevented from being triggered into cycle despite the MIP-1 alpha treatment. However, the MIP-1 alpha protocol used here did substantially decrease the number of more mature hematopoietic progenitors (granulocyte-macrophage colony-forming cells [CFC], burst- forming unit-erythroid, CFCmulti, and preCFCmulti) recovered in the bone marrow shortly after a single 5-FU injection. In vitro, MIP-1 alpha had no inhibitory effect on the ability of these progenitors to form colonies. This study confirms the in vivo inhibitory effect of MIP- 1 alpha on subpopulations of hematopoietic progenitors that are activated in myelodepressed animals. However, MIP-1 alpha had no effect on the long-term reconstituting stem cells in vivo under conditions in which it effectively reduced all later progenitors.  相似文献   
46.

Background

The unpredictable nature of the potentially devastating impact of 2009 pH1N1 influenza pandemic highlights the need for pandemic preparedness planning, where modeling studies could be most useful for simulations of possible future scenarios.

Methods

A compartmental model with pre-symptomatic and asymptomatic influenza infections is proposed which incorporates age groups as well as intervention measures such as age-specific vaccination, in order to study spread of influenza in a community.

Results

We derive the basic reproduction number and other effective reproduction numbers under various intervention measures. For illustration, we make use of the Pneumonia and Influenza (P&I) mortality data and vaccination data of the very young (age 0-2) and the very old (age >64) during 2004-2005 Taiwan winter influenza season to fit our model and to compute the relevant reproduction numbers. The reproduction number for this winter flu season is estimated to be slightly above one (~1.0001).

Conclusions

Comparatively large errors in fitting the P&I mortality data of the elderly (>64) were observed shortly after winter school closings in January, which may indicate the impact of younger, more active age groups transmitting influenza to other age groups outside of the school settings; in particular, to the elderly in the households. Pre-symptomatic infections seemed to have little effect on the model fit, while asymptomatic infection by asymptomatic infectives has a more pronounced impact on the model fit for the elderly mortality, perhaps indicating a larger role in disease transmission by asymptomatic infection. Simulations indicate that the impact of vaccination on the disease incidence might not be fully revealed in the change (or the lack thereof) in the effective reproduction number with interventions, but could still be substantial. The estimated per contact transmission probability for susceptible elderly is significantly higher than that of any other age group, perhaps highlighting the vulnerability of the elderly due to close contacts with their caretakers from other age groups. The relative impact of targeting the very young and the very old for vaccination was weakened by their relative inactivity, thus giving evidence of the lack of impact of vaccinating these two groups on the overall transmissibility of the disease in the community. This further underscores the need for morbidity-based strategy to prevent elderly mortality.  相似文献   
47.
48.
The paper describes a syphilitic lesion of the stomach in a man who for the first time consulted therapeutist and gastroenterologist with symptoms similar to stomach tumors. A possible infection took place during diagnostic fibrogastroscopy (FGS). Reiterated FGS did not permit endoscopists to suspect syphilis. The data of roentgenography fell into the pattern of stomach cancer. After additional examination with performance of specific seroreactions, an early latent syphilis was diagnosed. The treatment resulted in full clinico-serologic regression of the disease. A timely detection of syphilitic stomach lesion is a great problem if clinical manifestations are estimated separately from anamnestic data.  相似文献   
49.
To define the immunological functions of tumor necrosis factor (TNF) in Candida albicans infection, TNF/lymphotoxin (LT)-alpha double-deficient mice were assessed for susceptibility to systemic or gastrointestinal infection and parameters of innate and adaptive Th immunity. When compared to wild-type mice, TNF/LT-alpha-deficient mice were more susceptible to either type of infection caused by virulent or low- virulence C. albicans cells. Susceptibility to infection correlated with impaired development of protective Th1 responses, in spite of the production of bioactive IL-12. The occurrence of predominant Th2 responses was associated with both impaired antifungal effector functions of neutrophils and a defective expression of co-stimulatory molecules on macrophages. All functions were improved upon administration of recombinant TNF-alpha, also resulting in increased resistance to infection. These findings indicate that the protective effect of TNF-alpha in candidiasis relies on the induction of antifungal Th1 responses, possibly occurring through stimulation of antifungal effector functions and co-stimulatory activities of phagocytic cells.   相似文献   
50.
This article considers the processes of light propagation and scattering in biological tissues. The results obtained made it possible to estimate basic signal parameters and their dependence on various optical parameters with respect to the laser Doppler flowmeter and laser Doppler microscope. We also developed a new method to determine the indicatrix asymmetry of single and multiple light scattering by a suspension of oriented spheroidal particles that simulated erythrocytes in a shear flow. It was found that the angular dependence of the asymmetry index provides infonnation on the shape and orientation of particles. In addition, we obtained single scattering indicatrices, which may improve the accuracy of computer simulation of light scattering by blood.  相似文献   
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