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1.
Bone morphogenetic protein (BMP) is a potent induction factor for new bone formation including heterotopic chondro-ossification in soft tissues. The immunohistochemical reaction for BMP was studied in 23 cases of pleomorphic adenoma of salivary gland by using a monoclonal antibody produced by hybridoma technique. Positive BMP immunoreactivity was seen in 87% of tumours. Immunohistochemical expression of BMP was observed in modified myoepithelial cells (88% cases), luminal tumour cells of tubulo-ductal structures (78% cases) and chondroid cells in hyaline tissue (22% cases). The authors concluded that the simultaneous presence of glycosaminoglycans as matrix substance and S-100 protein for calcium signalling are associated with BMP-mediated cellular activity of modified myoepithelial cells in the formation of chondroid structures in pleomorphic adenomas of the salivary glands.  相似文献   
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Nivolumab and pembrolizumab are humanized IgG4 monoclonal antibodies against programmed cell death 1 (PD-1). Although these agents are effective in treating advanced melanoma, non-small-cell lung carcinoma, and other types of cancers, various adverse events have been reported. Cutaneous adverse events are particularly prevalent and, while granulomatous/sarcoid-like reactions are uncommon, they are increasingly recognized as immune-related adverse events associated with immune checkpoint inhibitors. Herein, we report two cases of granulomatous/sarcoid-like reaction with foreign material, mimicking metastatic malignancy after PD-1 inhibitor treatment. Clinicians should be aware of the existence of cutaneous lesions and perform biopsy if needed to prevent misdiagnosis and unnecessary adjustments to immunotherapy.  相似文献   
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Abstract: We present a case of severe exacerbation of hepatitis after short‐term corticosteroid therapy for chronic inflammatory demyelinating polyneuropathy (CIPD) with “latent” chronic hepatitis B showing no HBV‐related antigens and antibodies. After corticosteroid pulse therapy for CIPD, the patient had severe exacerbation of hepatitis twice. Although she did not show any hepatitis B virus (HBV)‐related antigens or antibodies, sequences of HBV were detected in serum and liver by a nested polymerase chain reaction. A sequence analysis of HBV at the second exacerbation showed that the G‐to‐A point mutation at nucleotide 1896 that converted codon 28 from tryptophan (TGG) to a stop codon (TAG) in the precore region resulted in amino acid change, which has been frequently observed in fulminant hepatitis and severe hepatitis in Japan.  相似文献   
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Aquaporins are water channel proteins which enable rapid water movement across the plasma membrane. Aquaporin-5 (AQP5) is the major aquaporin and is expressed on the apical membrane of salivary gland acinar cells. We examined the effects of repeated administration of pilocarpine, a clinically useful stimulant for salivary fluid secretion, and isoproterenol (IPR), a stimulant for salivary protein secretion, on the abundance of AQP5 protein in rat salivary glands by immunofluorescence microscopy and semi-quantitative immunoblotting. Unexpectedly AQP5 was decreased in pilocarpine-administered salivary glands, in which fluid secretion must be highly stimulated, implying that AQP5 might not be required for fluid secretion at least in pilocarpine-administered state. The abundance of AQP5, on the other hand, was found to be significantly increased in IPR-administered submandibular and parotid glands. To address the possible mechanism of the elevation of AQP5 abundance in IPR-administered animals, changes of AQP5 level in fasting animals, in which the exocytotic events are reduced, were examined. AQP5 was found to be decreased in fasting animals as expected. These results suggested that the elevation of cAMP and/or frequent exocytotic events could increase AQP5 protein. AQP5 expression seems to be easily changed by salivary stimulants, although these changes do not always reflect the ability in salivary fluid secretion.  相似文献   
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Whole-genome sequencing of non-H2S-producing Salmonella enterica serovar Typhimurium and S. enterica serovar Infantis isolates from poultry meat revealed a nonsense mutation in the phsA thiosulfate reductase gene and carriage of a CMY-2 β-lactamase. The lack of production of H2S might lead to the incorrect identification of S. enterica isolates carrying antimicrobial resistance genes.  相似文献   
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Cultured rat hepatocytes were used to study the effects of hormones on the production of apo A-I. In addition, we compared these effects with the production of albumin. Hepatocytes were isolated from normal adult rat livers and cultured in MEM, as nearly confluent monolayers. In the absence of hormones, apo A-I and albumin accumulated in the culture medium almost linearly for periods up to 24 h. The rates of accumulation of apo A-1 and albumin in the medium were 22 ng/mg cell protein per h and 1.2 μg/mg cell protein per h, respectively. During the incubations the cellular contents of apo A-1 remained constant.

Insulin stimulated the production of albumin at concentrations over 10−10 M, but inhibited the production of apo A-I at concentrations over 10−8 M. Dexamethasone showed no significant effects on albumin production but stimulated apo A-1 production at concentrations over 10−6 M. Glucagon inhibited the production of albumin and apo A-I dose-dependently at concentrations over 10−10 M. Thus, the production of albumin and apo A-1 are presumably controlled by different regulatory mechanisms.  相似文献   

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Objective To clarify the dose-related effects of direct hemoperfusion using a cytokine adsorbent column (CTR) on the mortality and inflammatory responses to endotoxin-induced shock in rats. Design Prospective and randomized study. Setting University research laboratory. Subjects Male Wistar rats. Interventions Forty-eight rats were injected intravenously with Escherichia coli endotoxin (15 mg/kg over 2 min), and then were randomly allocated to one of the following four groups (n = 12 per group): control group, treated without CTR for 120 min; quarter-dose treatment group, treated with CTR 0.25 ml for 120 min; half-dose treatment group, treated with CTR 0.50 ml; and full-dose treatment group, treated with CTR 1.0 ml. Measurements and results Hemodynamics and arterial blood gases were recorded, and mortality and plasma cytokine concentrations were calculated for the 8-h observation period. The mortality rates 8 h after endotoxin injection were 92%, 58%, 42% and 17% for the control column, quarter-dose, half-dose, and full-dose CTR groups, respectively. The increases in plasma cytokine concentrations were smaller in the half-dose and full-dose CTR treatment groups than in the endotoxemic group. Conclusions The present study showed that CTR treatment dose-dependently decreased the mortality rate and inhibited inflammatory responses in vivo. There was no supported funding in this study.  相似文献   
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