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Japanese yew is a widely used ornamental plant. However, most people are unaware that it is also a poisonous plant. It has potent cardiac toxicities that can lead to sudden cardiac death. A 37-year-old female patient presented to the emergency room with altered mental status and sustained ventricular tachycardia (VT). Electrocardiogram (ECG) after cardioversion showed profound QRS prolongation and ST-segment elevation suggestive of either hyperkalaemia, acute myocardial ischaemia, or Brugada syndrome. Her electrolytes and coronary angiography were normal. After improvement of the patient's mental status, she admitted that she has been consuming Japanese yew from her yard for several months. Few hours later, QRS duration normalised, but mild ST-segment elevation persisted in the right pre-cordial leads, making it more suspicious for Brugada syndrome. However, a procainamide challenge test and electrophysiology study failed to induce typical Brugada pattern ECG and VT. The absence of coronary artery disease and electrolytes disturbances points toward the fact that her arrhythmia and ECG changes are secondary to yew intoxication. The patient was monitored for a few days. She was haemodynamically stable and has not had any arrhythmia. This case highlights the importance of public awareness of severe toxicity from Japanese yew or other yew plants. Yews contain taxines that are responsible for the ECG abnormalities due to its inhibitory effect on the cardiac sodium and calcium channels. They cause conduction abnormalities, VT, and ST-segment elevation that can resemble acute myocardial infarction, hyperkalaemia, and Brugada syndrome.  相似文献   
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Background

Human induced pluripotent stem cells offer perspectives for cell therapy and research models for diseases. We applied this approach to the normal and pathological erythroid differentiation model by establishing induced pluripotent stem cells from normal and homozygous sickle cell disease donors.

Design and Methods

We addressed the question as to whether these cells can reach complete erythroid terminal maturation notably with a complete switch from fetal to adult hemoglobin. Sickle cell disease induced pluripotent stem cells were differentiated in vitro into red blood cells and characterized for their terminal maturation in terms of hemoglobin content, oxygen transport capacity, deformability, sickling and adherence. Nucleated erythroblast populations generated from normal and pathological induced pluripotent stem cells were then injected into non-obese diabetic severe combined immunodeficiency mice to follow the in vivo hemoglobin maturation.

Results

We observed that in vitro erythroid differentiation results in predominance of fetal hemoglobin which rescues the functionality of red blood cells in the pathological model of sickle cell disease. We observed, in vivo, the switch from fetal to adult hemoglobin after infusion of nucleated erythroid precursors derived from either normal or pathological induced pluripotent stem cells into mice.

Conclusions

These results demonstrate that human induced pluripotent stem cells: i) can achieve complete terminal erythroid maturation, in vitro in terms of nucleus expulsion and in vivo in terms of hemoglobin maturation; and ii) open the way to generation of functionally corrected red blood cells from sickle cell disease induced pluripotent stem cells, without any genetic modification or drug treatment.Key words: human induced pluripotent stem cells, terminal maturation, erythropoietic differentiation  相似文献   
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Background

Bioengineered skin substitutes are increasingly considered as a useful option for the treatment of full thickness burn injury. Their viability following grafting can be enhanced by seeding the skin substitute with late outgrowth endothelial progenitor cells (EPCs). However, it is not known whether autologous EPCs can be obtained from burned patients shortly after injury.

Methods

Late outgrowth EPCs were isolated from peripheral blood sampled obtained from 10 burned patients (extent 19.6 ± 10.3% TBSA) within the first 24 h of hospital admission, and from 7 healthy subjects. Late outgrowth EPCs were phenotyped in vitro.

Results

In comparison with similar cells obtained from healthy subjects, growing colonies from burned patients yielded a higher percentage of EPC clones (46 versus 17%, p = 0.013). Furthermore, EPCs from burned patients secreted more vascular endothelial growth factor (VEGF) into the culture medium than did their counterparts from healthy subjects (85.8 ± 56.2 versus 17.6 ± 14 pg/mg protein, p = 0.018). When injected to athymic nude mice 6 h after unilateral ligation of the femoral artery, EPCs from both groups of subjects greatly accelerated the reperfusion of the ischaemic hindlimb and increased the number of vascular smooth muscle cells.

Conclusions

The present study supports that, in patients with burns of moderate extension, it is feasible to obtain functional autologous late outgrowth EPCs from peripheral blood. These results constitute a strong incentive to pursue approaches based on using autotransplantation of these cells to improve the therapy of full thickness burns.  相似文献   
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Purpose

To examine the incidence of secondary primary malignancies in patients with renal cortical neoplasms.

Methods

Between January 1989 and July 2010, 3647 patients underwent surgery at our institution for a renal cortical neoplasm and were followed through 2012. Occurrence of other malignancies was classified as antecedent, synchronous, or subsequent. All patients with antecedent malignancies (n = 498) and a randomly selected half of those with synchronous malignancies (n = 83) were excluded. The expected number of second primaries was calculated by multiplying Surveillance, Epidemiology, and End Results Program incidence rates of renal cortical neoplasms by person-years at risk within categories of age, sex, and year of diagnosis. The standardized incidence ratio (SIR) was calculated as observed cancers divided by expected incidence of the cancer, with approximation to the exact Poisson test used to obtain confidence intervals (CI) and p values.

Results

Of 3066 patients with renal cortical neoplasms, 267 had a second primary cancer; the five most common in men were prostate, colorectal, bladder, lung, and non-Hodgkin’s lymphoma; the five most common in women were breast, colorectal, lung, endometrium, and thyroid. Men demonstrated higher than expected thyroid cancer rate (SIR 5.0; 95 % CI 1.83–10.88, p = 0.002), and women had higher than expected rates of stomach cancer (SIR 5.0; 95 % CI 1.61–11.67, p = 0.004) and thyroid cancer (SIR 4.62; 95 % CI 1.69–10.05, p = 0.003).

Conclusions

The incidence of certain types of second malignancies may be higher in patients after diagnosis of renal cortical neoplasms compared to the general population. These observations can inform clinical follow-up in kidney cancer survivorship and future research studies.
  相似文献   
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