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We systematically reviewed the existing evidence to determine whether a relationship exists between infection with human herpesvirus 6 (HHV-6) and multiple sclerosis (MS) and, if so, to define the strength of that relationship. The following terms were used in searches of the Entrez-PubMed database (1966-2009): human herpes virus 6, HHV 6, demyelination, multiple sclerosis, pathogenesis, diagnosis, serology, cerebrospinal fluid, IgG antibodies, IgM antibodies, PCR, and lymphoproliferative techniques. Study quality was assessed using the criteria proposed by Moore and Wolfson and by the classification criteria used by the Canadian Task Force on the Periodic Health Examination. Studies were categorized both by experimental technique and by quality (high [A], intermediate [B], and low [C]) as determined by the Moore and Wolfson criteria. Overall, 25 (41%) of 61 studies, 15 (60%) of which were classified as A quality, reached a statistically significant result. According to the Canadian Task Force classification, all studies were categorized as evidence of quality II-1. Limitations of the available experimental techniques and perspectives for future research are discussed. The current review supports the need for further, objective, evidence-based examination of the relationship between HHV-6 infection and multiple sclerosis.  相似文献   
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AIMS: This study evaluates if a computed tomography (CT) scan is useful to assess the olfactory loss in sinonasal disease, and if a preoperative CT scan has a predictive value for the long-term outcome regarding olfaction. METHODS: Thirty-one patients with nasal polyposis were included. Olfactory function was assessed with the 'Sniffin' Sticks' test and subjective perception recorded with a visual analogue scale. CT scans were assessed with the Lund-Mackay system and the Damm nasal segmentation. Patients were retested after endoscopic sinus surgery in a follow-up appointment at least 1 year later. RESULTS: Disease in the upper meatus and the posterior portion of the middle meatus strongly affects olfactory function. Lund-Mackay scores were significantly correlated with preoperative olfactory test results. Preoperative subjective ratings had a significant correlation only with present disease in the anterior upper meatus. Postoperative results were significantly decreased. Their relative percentage change was correlated only with the preoperative presence of disease in the anterior upper meatus. No correlation was found between the Lund-Mackay score and the postoperative olfactory results. CONCLUSIONS: Olfactory dysfunction in nasal polyposis is strongly related to specific obstructed nasal areas. A CT scan has no predictive value for the long-term surgical outcome regarding olfaction.  相似文献   
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OBJECTIVE: The aim of this study was to examine the effect of the number of averaged responses on the measurement of transiently evoked otoacoustic emissions (TEOAEs). METHODS: The study was performed on the background of a universal newborn hearing screening program implemented in Iaso Maternity Hospital. Two groups of full-term newborns with normal otoacoustic emissions were studied. The first group included 58 newborns (115) ears, in which 260 low-noise samples, provided by the default setting of the equipment used (ILO88), were presented. The second group included 58 newborns (113) ears, in which 20-50 averaged responses were presented, until the "pass" criteria would be met. Statistical comparison between the following parameters recorded during TEOAE measurement was performed: Overall response, signal-to-noise ratios, reproducibility (whole and partial), stimulus intensity, stimulus stability, input noise, noise rejection level and duration of testing. RESULTS: Statistically significant differences were found in most of these parameters, except for overall response, stimulus intensity and noise rejection level. CONCLUSIONS: Although a smaller number of clicks is usually sufficient to obtain a "pass" in newborn hearing screening programs, the quality of recording of TEOAEs is significantly improved by increasing the number of averaged low-noise responses.  相似文献   
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Wine has been part of human culture for 6,000 years, serving dietary and socioreligious functions. Its production takes place on every continent, and its chemical composition is profoundly influenced by enological techniques, the grape cultivar from which it originates, and climatic factors. In addition to ethanol, which in moderate consumption can reduce mortality from coronary heart disease by increasing high-density lipoprotein cholesterol and inhibiting platelet aggregation, wine (especially red wine) contains a range of polyphenols that have desirable biological properties. These include the phenolic acids (p-coumaric, cinnamic, caffeic, gentisic, ferulic, and vanillic acids), trihydroxy stilbenes (resveratrol and polydatin), and flavonoids (catechin, epicatechin, and quercetin). They are synthesized by a common pathway from phenylalanine involving polyketide condensation reactions. Metabolic regulation is provided by competition between resveratrol synthase and chalcone synthase for a common precursor pool of acyl-CoA derivatives. Polymeric aggregation gives rise, in turn, to the viniferins (potent antifungal agents) and procyanidins (strong antioxidants that also inhibit platelet aggregation). The antioxidant effects of red wine and of its major polyphenols have been demonstrated in many experimental systems spanning the range from in vitro studies (human low-density lipoprotein, liposomes, macrophages, cultured cells) to investigations in healthy human subjects. Several of these compounds (notably catechin, quercetin, and resveratrol) promote nitric oxide production by vascular endothelium; inhibit the synthesis of thromboxane in platelets and leukotriene in neutrophils, modulate the synthesis and secretion of lipoproteins in whole animals and human cell lines, and arrest tumour growth as well as inhibit carcinogenesis in different experimental models. Target mechanisms to account for these effects include inhibition of phospholipase A2 and cyclo-oxygenase, inhibition of phosphodiesterase with increase in cyclic nucleotide concentrations, and inhibition of several protein kinases involved in cell signaling. Although their bioavailability remains to be fully established, red wine provides a more favourable milieu than fruits and vegetables, their other dietary source in humans. J. Clin. Lab. Anal. 11:287–313, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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Bone morphogenetic proteins (BMPs) are a group of growth factors with dual functions in cancer development and progression. Recently, certain tumor‐promoting roles have been identified for selected antagonists/inhibitors (BMPIs) of this developmental pathway. A recent focus on the implication of BMP in colorectal cancer progression has emerged, mainly due to the presence of inactivating mutations in several members of the canonical signaling cascade. However, the detailed expression profiles of BMPIs remain largely unknown. Based on our previous work, whereby three specific BMPIs, gremlin‐1 (GREM1), high‐temperature requirement A3 (HTRA3) and follistatin (FST) were collectively overexpressed in desmoplastic cocultures of colorectal cancer (CRC), here, we undertook an immunohistochemical approach to describe the patterns of their expression in CRC patients. Two major characteristics described the BMPI expression signature: First, the synchronous and coordinated stromal and epithelial overexpression of individual BMPIs in desmoplastic lesions, which demonstrated that all three of them contribute to increasing levels of BMP antagonism in such areas. Second, the presence of microenvironmental polarity in the BMPI pattern of expression, which was indicated through the preferential expression of HTRA3 in the stromal, and the parallel FST/GREM1 expression in the epithelial component of the investigated sections. In addition, expression of HTRA3 in the epithelial compartment of the tumors demonstrated a significant predictive power to discriminate between tumor‐budding‐bearing and tumor‐budding‐free desmoplastic microenvironments. Together, these findings contribute to the understanding of signaling dynamics of BMP antagonism in the colorectal cancer desmoplastic invasion front.  相似文献   
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