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21.
Bone-marrow regeneration after chemo- and radiotherapy-induced aplasia can be monitored by serum levels of myeloperoxidase (MPO), lysozyme (LYS) and lactoferrin (LF). In 10 patients with leukemia, serum measurements were performed before and after bone-marrow transplantation. Bone-marrow regeneration was suggested by increments in serum MPO and LYS 5 and 4 days prior to the increase in mononuclear cells (Mono) and 10 and 9 d before the increase in polymorphonuclear leukocytes (PMN) in the peripheral blood. LF started to rise 4.5 d before detectable circulating PMNs. 2 patients with early relapses of leukemia post transplantation are shown to display atypical patterns of serum MPO and LYS. We conclude that serum measurements of MPO, LYS and LF may be used as early and sensitive means to monitor bone-marrow activity during hematological regeneration. However, the findings also strongly support the earlier proposal that MPO alone may be used to reflect myeloid activity in the bone-marrow in general.  相似文献   
22.
The significance of white blood cells in the ejaculate remains a matter of controversy. Several authors have suggested that such cells are important in the modulation of an antisperm antibody response, i.e. a predominance of suppressor/cytotoxic to helper/inducer T cells may prevent the development of antisperm antibodies. In order to examine this relationship further we have documented the white blood cell types, with emphasis on the T-lymphocyte populations, in the ejaculates of men from infertile couples with and without antisperm antibodies; the latter group was divided further into two groups--vasovasostomized men and idiopathic men. All seven of the men without antisperm antibodies had a predominance of suppressor/cytotoxic T cells to helper/inducer T cells in the ejaculate. However, only in some of the men with antibodies was there a predominance of T-helper/inducer cells. It is clear that the relationship between antisperm antibodies and seminal leucocytes is therefore not as straightforward as has been proposed.  相似文献   
23.
Modafinil is a new drug used in the treatment of narcolepsy. Its administration in mice induced a dose-dependent increase in locomotor activity. The effects of modafinil were compared with those of dexamphetamine on three tests that assessed the anxiety level (drugs were used at doses which induced a roughly similar stimulation of locomotor activity). Dexamphetamine increased the latency of exploration of a white compartment, increased thigmotaxis in an open-field and decreased the time spent in the open arms of an elevated plus-maze. None of these responses was significantly modified by modafinil. We conclude that modafinil does not share the anxiogenic effects of dexamphetamine.  相似文献   
24.
We report on a male patient with Pick disease who had shown severe white matter atrophy and dilatation of the lateral ventricle in the frontal lobe from an early stage. Upon admission to our hospital 2 years after disease onset, the patient showed apathy, and MRI revealed severe atrophy of the cortex and white matter of the frontal lobe. He died at age 74, 11 years after disease onset. Autopsy revealed severe atrophy of the frontal and temporal lobes, severe loss of white matter in the frontal lobe, dilatation of the lateral ventricles, and cortical thinning. Histopathological examination showed severe loss of myelinated fibers in the frontal white matter and severe neuronal loss with gliosis in the frontal and temporal cortices. Many Pick bodies were seen. Our patient had a rare case of Pick disease predominantly affecting the frontal lobe with severe involvement of the white matter from an early stage. This case suggests that myelinated fibers in the white matter as well as cerebral neurons are primarily affected in Pick disease.  相似文献   
25.
We investigated whether structural white matter abnormalities, in the form of disruption of axonal coherence and integrity as measured with diffusion tensor imaging (DTI), constitute an underlying pathological mechanism of idiopathic dystonia (ID), independent of genotype status. We studied seven subjects with ID: all had cervical dystonia as their main symptom (one patient also had spasmodic dysphonia and two patients had concurrent generalized dystonia, both DYT1‐negative). We compared DTI MR images of patients with 10 controls, evaluating differences in mean diffusivity (MD) and fractional anisotropy (FA). ID was associated with increased FA values in the thalamus and adjacent white matter, and in the white matter underlying the middle frontal gyrus. ID was also associated with increase in MD in adjacent white matter to the pallidum and putamen bilaterally, left caudate, and in subcortical hemispheric regions, including the postcentral gyrus. Abnormal FA and MD in patients with ID indicate that abnormal axonal coherence and integrity contribute to the pathophysiology of dystonia. These findings suggest that ID is not only a functional disorder, but also associated with structural brain changes. Impaired connectivity and disrupted flow of information may contribute to the impairment of motor planning and regulation in dystonia. © 2006 Movement Disorder Society  相似文献   
26.
深部脑白质缺血影像表现与MTHFR基因多态性关系的探讨   总被引:1,自引:0,他引:1  
目的:探讨MTHFR的纯合突变TT型基因是否为诱发皮层下深部脑白质缺血的危险因子,并证实皮层下深部脑白质缺血影像表现与MTHFR基因C/T多态性的关系。资料与方法:选择影像表现符合皮层下深部脑白质缺血诊断标准者30例,对照组30例为影像表现正常者,运用多聚酶链反应-限制性内切酶片段长度多态性技术(PCR-RFLP)检测两组MTHFR基因多态性。结果:采用χ^2检验,得出MTHFR基因纯合突变TT型在病变组与对照组比较差异有显著性(χ^2=5.0794,P<0.05),病变组TT型较对照组显著升高,说明MTHFR的纯合突变TT型可能是诱发深部脑白质缺血的危险因素。运用成组设计两样本比较的秩和检验,得出TT型和非TT型患者在影像表现的分级程度上有差别,携带TT型基因者影像表现分级重。结论:MTHFR纯合突变TT型基因是深部脑白质缺血发病的危险因子,且TT型基因与深部脑白质缺血的易感性和影像表现呈明显正相关。  相似文献   
27.
Tissue microarrays (TMA) consist of up to 1000 cylindrical tissue cores from different donor paraffin blocks relocated into one recipient block, allowing for efficient histopathological studies by fluorescence in situ hybridization, RNA in situ hybridization or immunohistochemistry. On the background of the increasing interest of the TMA technique in cancer research and the suggestion of its application also in studies of non‐neoplastic intracranial disorders, the technique was applied to pathologic white matter in AD brains. Eight cases with AD and concomitant white matter pathology were neuropathologically diagnosed on whole brain coronal slides. The TMA technique was used to grade severity of white matter pathology and to quantify small vessels with traditional staining and immunohistochemical markers. These measurements were compared with the whole brain neuropathological assessment. The technique produced good results with preserved tissue structures as confirmed by the whole brain evaluation. Severity of white matter pathology evaluated on the TMA cores correlated negatively with small vessel quantities, and statistically significant differences in vessel quantities paralleled different grades of white matter pathology. It is concluded that the TMA technique could be further utilized in studies of dementing disorders, and may have its advantages in large, clinically well‐characterized materials (e.g. in quantitative mapping of white matter changes).  相似文献   
28.
Abstract: Previously it has been found that rat small bowel crypt cell hyperplasia occurred several weeks after pinealectomy. To determine if this effect was longer-lasting (because of the possible role of the pineal in bowel malignancy) the crypt cell proliferation rate was determined in rat small bowel and colon 6 months after pinealectomy, using a stathmokinetic technique. Although the hyperproliferative effect of pinealectomy was well maintained in the small bowel crypts after 6 months, the hyper proliferative effect in the colonic crypts was much less marked. There is no obvious explanation for these findings, although it is possible that regional differences in levels of gut neuropeptides or melatonin are involved. The mechanism of the effect of pinealectomy on the crypts remains unexplained—in particular, why the effect is so prolonged.  相似文献   
29.
As an avian embryo grows within a eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat. A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure the cardiogenic ballistic movement of the egg or ballistocardiogram. (BCG). In this context, there is interest in using an electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system. Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs, indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of the velocity of egg movements.  相似文献   
30.
抗白色念珠菌鸡卵黄抗体(IgY)的研制   总被引:4,自引:0,他引:4  
目的:观察鸡蛋黄中抗体的产量、纯度、来源及稳定性。方法:应用白色念珠菌作为抗原免疫25周龄Leghorn鸡,通过改良水溶法(WD)提取蛋黄中抗体IgY,双紫外光测定抗体含量,SDS-APGE电泳检测抗体纯度,Western blot免疫印迹法测定该抗体来源,ELISA检测热处理后的抗体活性。结果:抗体含量13mg/ml蛋黄液,抗体纯度达到95%,Western blot免疫印迹证明该抗体与鸡血清中的IgG具有相同的分子量和抗原性。ELISA检测热处理后的抗体活性,其具有良好的热稳定性。结论:鸡蛋黄内含有丰富的抗体,通过WD水溶提取法可得到高产量,高纯度的特异性抗体IgY,证明其来源于鸡血清中的IgG,对热具有高度稳定性。  相似文献   
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