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31.
ObjectiveFrom data in the literature, we hypothesized that high vascular resistance values in the uterine arteries at the end of the first trimester would increase adverse pregnancy outcomes and therefore might be accompanied by changes in VEGF/VEGFR1 immunoreactivities.Study designIn our university hospital 82 women (Study I n = 62 and Study II n = 20) were divided into two groups according to their uterine vascular resistance values. Uterine vascular resistance values were measured in the 10–13th weeks of gestation by color-Doppler ultrasonography. Women were divided into low and high vascular resistance groups. In the prospective follow-up study (Study I) the data of the pregnancy outcome were recorded. In cross-sectional study (Study II), VEGF and VEGFR1 immunoreactivities were measured on the tissue samples from women who underwent termination of pregnancy.ResultsIn the high vascular resistance group (PI > 2.3), the probability of adverse pregnancy outcome was significantly higher (40.0% vs. 12.8%). No differences in VEGF and VEGFR1 immunoreactivities were observed between groups. In both groups, intense VEGF immunoreactivity was observed in the maternal glandular epithelium and in the decidual cells. Weak reactivity was observed in the villous trophoblast. VEGFR1 immunoreactivity was intense in all regions.ConclusionsOur data suggest that high vascular resistance values in the first trimester are independent from VEGF/VEGFR1 immunoreactivities and markedly increase the probability of adverse pregnancy outcomes. This may be used for early screening of pregnant women in the first trimester.  相似文献   
32.
Dysregulation of neuropeptides may play an important role in aging‐induced impairments. Among them, pituitary adenylate cyclase‐activating polypeptide (PACAP) is a potent cytoprotective peptide that provides an endogenous control against a variety of tissue‐damaging stimuli. We hypothesized that the progressive decline of PACAP throughout life and the well‐known general cytoprotective effects of PACAP lead to age‐related pathophysiological changes in PACAP deficiency, supported by the increased vulnerability to various stressors of animals partially or totally lacking PACAP. Using young and aging CD1 PACAP knockout (KO) and wild type (WT) mice, we demonstrated pre‐senile amyloidosis in young PACAP KO animals and showed that senile amyloidosis appeared accelerated, more generalized, more severe, and affected more individuals. Histopathology showed age‐related systemic amyloidosis with mainly kidney, spleen, liver, skin, thyroid, intestinal, tracheal, and esophageal involvement. Mass spectrometry‐based proteomic analysis, reconfirmed with immunohistochemistry, revealed that apolipoprotein‐AIV was the main amyloid protein in the deposits together with several accompanying proteins. Although the local amyloidogenic protein expression was disturbed in KO animals, no difference was found in laboratory lipid parameters, suggesting a complex pathway leading to increased age‐related degeneration with amyloid deposits in the absence of PACAP. In spite of no marked inflammatory histological changes or blood test parameters, we detected a disturbed cytokine profile that possibly creates a pro‐inflammatory milieu favoring amyloid deposition. In summary, here we describe accelerated systemic senile amyloidosis in PACAP gene‐deficient mice, which might indicate an early aging phenomenon in this mouse strain. Thus, PACAP KO mice could serve as a model of accelerated aging with human relevance. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
33.
IgG has the longest survival time in the circulation of the Ig classes and the lowest fractional catabolic rate. The neonatal Fc receptor (FcRn) plays an important role in regulating these processes. Recently, we have cloned the bovine neonatal Fc receptor (bFcRn) alpha chain and detected its expression in various epithelial cells which are mediating IgG secretion. However, its function in IgG homeostasis has not been investigated. In the current study, we analyzed the binding affinity of bovine and human IgGs to bFcRn using surface plasmon resonance and by in vitro radioreceptor binding assays. As human IgG binds stronger to the bFcRn, than bovine IgG at pH 6, we subsequently analyzed its catabolism in normal and transchromosomic calves that produce human Igs. Pharmacokinetic studies showed that human IgG had approximately 33 days serum half-life both in normal and transchromosomic calves, which is more than two times longer than its bovine counterpart. We also demonstrate FcRn expression in endothelial cells and in the kidney which are supposed to be involved in IgG metabolism. These data suggest that bFcRn is involved in IgG homeostasis in cattle and furthermore, that the transchromosomic calves producing human Igs can effectively protect their human IgGs which have implications for successful large-scale production of therapeutic antibodies.  相似文献   
34.
Casali P  Pal Z  Xu Z  Zan H 《Trends in immunology》2006,27(7):313-321
Somatic hypermutation (SHM) underlies the generation of a diverse repertoire of high-affinity antibodies. It is effected by a two-step process: (i) DNA lesions initiated by activation-induced cytidine deaminase (AID), and (ii) lesion repair by the combined intervention of DNA replication and repair factors that include mismatch repair (MMR) proteins and translesion DNA synthesis (TLS) polymerases. AID and TLS polymerases that are crucial to SHM, namely polymerase (pol) theta, pol zeta and pol eta, are induced in B cells by the stimuli that are required to trigger this process: B-cell receptor crosslinking and CD40 engagement by CD154. These polymerases, together with MMR proteins and other DNA replication and repair factors, could assemble to form a multimolecular complex ("mutasome") at the site of DNA lesions. Molecular interactions in the mutasome would result in a "polymerase switch", that is, the substitution of the high-fidelity replicative pol delta and pol epsilon with the TLS pol theta, pol eta, Rev1, pol zeta and, perhaps, pol iota, which are error-prone and crucially insert mismatches or mutations while repairing DNA lesions. Here, we place these concepts in the context of the existing in vivo and in vitro findings, and discuss an integrated mechanistic model of SHM.  相似文献   
35.
Gene therapy is a promising strategy for the treatment of several inherited and acquired human diseases. Several vector platforms exist for the delivery of therapeutic nucleic acids into cells. Vectors based on viruses are very efficient at introducing gene constructs into cells, but their use has been associated with genotoxic effects of vector integration or immunological complications due to repeated administration in vivo. Non-viral vectors are easier to engineer and manufacture, but their efficient delivery into cells is a major challenge, and the lack of their chromosomal integration precludes long-term therapeutic effects. Transposable elements are non-viral gene delivery vehicles found ubiquitously in nature. Transposon-based vectors have the capacity of stable genomic integration and long-lasting expression of transgene constructs in cells. Molecular reconstruction of Sleeping Beauty, an ancient transposon in fish, represents a cornerstone in applying transposition-mediated gene delivery in vertebrate species, including humans. This review summarizes the state-of-the-art in the application of transposable elements for therapeutic gene transfer, and identifies key targets for the development of transposon-based gene vectors with enhanced efficacy and safety for human applications.  相似文献   
36.
To analyse the sensitivity and role of somatosensory and motor evoked potentials (EP) in patients with a first episode of clinically isolated optic neuritis (ON) in predicting the development and course of multiple sclerosis (MS), 27 patients with ON underwent EP and magnetic resonance imaging (MRI) examinations at presentation. Follow-up MRI scans were also performed (mean: 20, range: 4-48 months). It was found that 2/27 patients did not fulfill the MRI (McDonald) and clinical criteria of MS upon follow-up and also had normal EP results. Abnormal EP results were found in 6/27 patients and all of them had follow-up MRI results fulfilling the revised McDonald criteria of MS; 4/6 patients in this group were also diagnosed as clinically definitive MS. The majority, 19/27 patients had normal EP results, but went on to develop MS based on follow-up MRI results and McDonald criteria. Of these patients, however, only 3/19 converted to clinically definitive MS as well. The baseline MRI was abnormal in similar proportions (4/6 and 12/19) in these last two groups of patients. Thus, abnormal EP examinations at the first episode of ON can be considered as a predictive factor only for the earlier clinical conversion to MS - in this respect, however, being more sensitive than the initial MRI - and as such they may contribute to the delineation of the patient group who may benefit from early immunomodulatory treatment. They do not however have a predictive value for the development of MS itself as diagnosed by the McDonald criteria.  相似文献   
37.

Objective

To explore the predictive value of parameters derived from diffusion-weighted imaging (DWI) and contrast-enhanced (CE)-MRI at different time-points during neoadjuvant chemotherapy (NACT) in breast cancer.

Methods

Institutional review board approval and written, informed consent from 42 breast cancer patients were obtained. The patients were investigated before and at three different time-points during neoadjuvant chemotherapy (NACT) using tumour diameter and volume from CE-MRI and ADC values obtained from drawn 2D and segmented 3D regions of interest. Prediction of pathologic complete response (pCR) was evaluated using the area under the curve (AUC) of receiver operating characteristic analysis.

Results

There was no significant difference between pathologic complete response and non-pCR in baseline size measures (p?>?0.39). Diameter change was significantly different in pCR (p?<?0.02) before the mid-therapy point. The best predictor was lesion diameter change observed before mid-therapy (AUC?=?0.93). Segmented volume was not able to differentiate between pCR and non-pCR at any time-point. The ADC values from 3D-ROI were not significantly different from 2D data (p?=?0.06). The best AUC (0.79) for pCR prediction using DWI was median ADC measured before mid-therapy of NACT.

Conclusions

The results of this study should be considered in NACT monitoring planning, especially in MRI protocol designing and time point selection.

Key Points

? Mid-therapy diameter changes are the best predictors of pCR in neoadjuvant chemotherapy. ? Volumetric measures are not strictly superior in therapy monitoring to lesion diameter. ? Size measures perform as a better predictor than ADC values.
  相似文献   
38.
Abstract In the highly coordinated programme of gene expression during keratinocyte proliferation and differentiation, ·5 integrin and keratins 1 and 10 (K1/K10) may play important regulatory roles. We were interested in seeing whether, in continuously growing, immortalized HaCaT keratinocytes, similar to normal keratinocytes, the expression of ·5 integrin and K1/K10 was related to cell proliferation and differentiation. After release from cell quiescence the expression of ·5 integrin, both at the mRNA and protein levels, was upregulated in the cells. At the same time, K1/K10 mRNA and protein expression decreased dramatically, while the mRNA for D1 cyclin became detectable, and the cells became highly proliferative. These findings indicate that ·5 integrin and K1/K10 are involved in the regulation of HaCaT proliferation and differentiation, as in normal keratinocytes. However, HaCaT cells are different from normal keratinocytes in their ability to lose K1/K10 expression. There is no evidence that the expression of K1/K10 can be reversed in normal keratinocytes. This ability of dedifferentiation might be a unique feature of HaCaT cells and may be a key component of their immortalized nature. We also found that serum factors regulate mRNA expression of ·5 integrin and K1, but not of K10, in HaCaT cells. This information could be relevant to the understanding of normal epidermal differentiation. Received: 28 August 2000 / Revised: 27 October 2000 / Accepted: 3 February 2001  相似文献   
39.
TASK-3 (KCNK9 or K2P9.1) channels are thought to promote proliferation and/or survival of malignantly transformed cells, most likely by increasing their hypoxia tolerance. Based on our previous results that suggested mitochondrial expression of TASK-3 channels, we hypothesized that TASK-3 channels have roles in maintaining mitochondrial activity. In the present work we studied the effect of reduced TASK-3 expression on the mitochondrial function and survival of WM35 and A2058 melanoma cells. TASK-3 knockdown cells had depolarized mitochondrial membrane potential and contained a reduced amount of mitochondrial DNA. Compared to their scrambled shRNA-transfected counterparts, they demonstrated diminished responsiveness to the application of the mitochondrial uncoupler [(3-chlorophenyl)hydrazono]malononitrile (CCCP). These observations indicate impaired mitochondrial function. Further, TASK-3 knockdown cells presented reduced viability, decreased total DNA content, altered cell morphology, and reduced surface area. In contrast to non- and scrambled shRNA-transfected melanoma cell lines, which did not present noteworthy apoptotic activity, almost 50 % of the TASK-3 knockdown cells exhibited strong Annexin-V-specific immunofluorescence signal. Sequestration of cytochrome c from the mitochondria to the cytosol, increased caspase 3 activity, and translocation of the apoptosis-inducing factor from mitochondria to cell nuclei were also demonstrated in TASK-3 knockdown cells. Interference with TASK-3 channel expression, therefore, induces caspase-dependent and -independent apoptosis of melanoma cells, most likely via causing mitochondrial depolarization. Consequently, TASK-3 channels may be legitimate targets of future melanoma therapies.  相似文献   
40.
Pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38) and its receptors have been shown in the spinal dorsal horn, on capsaicin-sensitive sensory neurons and inflammatory cells. The role of PACAP in central pain transmission is controversial, and no data are available on its function in peripheral nociception. Therefore, the aim of the present study was to analyze the effects of locally or systemically administered PACAP-38 on nocifensive behaviors, inflammatory/neuropathic hyperalgesia and afferent firing. Intraplantar PACAP-38 (0.2 nmol) injection inhibited carrageenan-evoked inflammatory mechanical allodynia, mild heat injury-induced thermal hyperalgesia, as well as nocifensive behaviors in the early and late phases of the formalin test in rats. However, the above dose did not alter basal mechanical or heat thresholds. In mice, PACAP-38 (0.2 nmol/kg s.c.) significantly diminished acetic acid-induced abdominal contractions, but exerted no effect on sciatic nerve ligation-induced neuropathic mechanical hyperalgesia. In contrast, local PACAP-38 injection markedly increased rotation-induced afferent firing in the inflamed rat knee joint clearly demonstrating a peripheral sensitization in this organ. These actions were blocked by VPAC1/VPAC2 receptor antagonist pretreatment, but were not altered by PAC1 receptor antagonism. This paper presents the first data for the peripheral actions of PACAP-38 on nociceptive transmission mediated by VPAC receptors. These effects seem to be divergent depending on the mechanisms of nociceptor activation and the targets of PACAP actions. In acute somatic and visceral inflammatory pain models, PACAP exerts anti-nociceptive, anti-hyperalgesic and anti-allodynic effects. It has no significant peripheral role in traumatic mononeuropathy, but induces mechanical sensitization of knee joint primary afferents.  相似文献   
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