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991.
Dog spontaneously develop prostate cancer (PC) like humans. Because most dogs with PC have a poor prognosis, they could be used as a translational model for advanced PC in humans. Stem cell‐derived 3‐D organoid culture could recapitulate organ structures and physiology. Using patient tissues, a human PC organoid culture system was established. Recent study has shown that urine cells also possess the characteristic of stem cells. However, urine cell‐derived PC organoids have never been produced. Therefore, we generated PC organoids using the dog urine samples. Urine organoids were successfully generated from each dog with PC. Each organoid showed cystic structures and resembled the epithelial structures of original tissues. Expression of an epithelial cell marker, E‐cadherin, and a myofibloblast marker, α‐SMA, was observed in the urine organoids. The organoids also expressed a basal cell marker, CK5, and a luminal cell marker, CK8. CD49f‐sorted basal cell organoids rapidly grew compared with CD24‐sorted luminal cell organoids. The population of CD44‐positive cells was the highest in both organoids and the original urine cells. Tumors were successfully formed with the injection of the organoids into immunodeficient mice. Treatment with a microtubule inhibitor, docetaxel, but not a cyclooxygenase inhibitor, piroxicam, and an mTOR inhibitor, rapamycin, decreased the cell viability of organoids. Treatment with a Hedgehog signal inhibitor, GANT61, increased the radiosensitivity in the organoids. These findings revealed that PC organoids using urine might become a useful tool for investigating the mechanisms of the pathogenesis and treatment of PC in dogs.  相似文献   
992.
Recent clinical trials indicated that the intensive glycemic control do not reduce cardiovascular disease mortality among diabetic patients, challenging a significance of the strict glycemic control in diabetes management. Furthermore, retrospective analysis of the Action to Control Cardiovascular Risk in Diabetes study demonstrated a significant association between hypoglycemia and mortality. Here, we systematically reviewed the drug-induced hypoglycemia, and also the underlying clinical factors for hypoglycemia in patients with diabetes. The sulfonylurea use is significantly associated with severe hypoglycemia in patients with type 2 diabetes. The use of biguanide (approximately 45%-76%) and thiazolidinediones (approximately 15%-34%) are also highly associated with the development of severe hypoglycemia. In patients treated with insulin, the intensified insulin therapy is more frequently associated with severe hypoglycemia than the conventional insulin therapy and continuous subcutaneous insulin infusion. Among the underlying clinical factors for development of severe hypoglycemia, low socioeconomic status, aging, longer duration of diabetes, high HbA1c and low body mass index, comorbidities are precipitating factors for severe hypoglycemia. Poor cognitive and mental functions are also associated with severe hypoglycemia.  相似文献   
993.
994.
A pancreatic tumor was suspected on the abdominal ultrasound of a 72-year-old man. Abdominal computed tomography showed pancreatic enlargement as well as a diffuse, poorly enhanced area in the pancreas; endoscopic ultrasound-guided fine needle aspiration biopsy and endoscopic retrograde cholangiopancreatography failed to provide a definitive diagnosis. Based on the trend of improvement of the pancreatic enlargement, the treatment plan involved follow-up examinations. Later, he was hospitalized with an alveolar hemorrhage and rapidly progressive glomerulonephritis; he tested positive for myeloperoxidase-anti-neutrophil cytoplasmic antibody(ANCA) and was diagnosed with ANCArelated vasculitis, specifically microscopic polyangiitis. It appears that factors such as thrombus formation caused by the vasculitis in the early stages of ANCArelated vasculitis cause abnormal distribution of the pancreatic blood flow, resulting in non-uniform pancreatitis. Pancreatic lesions in ANCA-related vasculitis are very rare. Only a few cases have been reported previously. Therefore, we report our case and a review of the literature.  相似文献   
995.
Cysticercosis caused by infection with embryonated eggs of Taenia solium is an important cause of neurological disease worldwide. On the basis of mitochondrial DNA analysis, T. solium is divided into 2 (African/American and Asian) genotypes. Glycoproteins (GPs) in cyst fluid purified from the 2 genotypes of T. solium were characterized and compared with the recombinant chimeric T. solium-Ag1V1/Ag2 protein (Rec-Ag1V1/Ag2) as serodiagnostic antigens. Immunoblot analysis revealed that banding patterns of GPs differed between the 2 genotypes because of posttranslation modification, especially glycosylation. The comparison of native GPs with Rec-Ag1V1/Ag2 by enzyme-linked immunosorbent assay demonstrated that there was no statistical difference in sensitivity. In addition, the conservation of the genes encoding Ag1V1 and Ag2 in T. solium worldwide was verified. These results indicate that Rec-Ag1V1/Ag2 has great potential for usefulness in serodiagnosis as an alternative to native antigens.  相似文献   
996.
BACKGROUND: Nitric oxide (NO) produced by endothelial NO synthase (eNOS) is thought to effect an anti-inflammatory response, but its mechanism is still unknown. METHODS: eNOS transgenic (eNOS-TG) mice and their littermate controls (C57/BL6) were used to clarify the role of NO derived from eNOS. Bleomycin hydrochloride (1 U/body/day) or PBS was injected intraperitoneally. RESULTS: Subpleural fibrotic changes and hydroxyproline content in the eNOS-TG mice were significantly reduced compared with those of the wild-type (WT) mice by day 56. Administration of N(omega)-nitro-L-arginine methyl ester, a potent inhibitor of NO synthase, worsened the fibrotic response in bleomycin-treated eNOS-TG mice. Gelatinolytic activity in lung homogenates, corresponding to metalloproteinase-9 (MMP-9), was significantly increased in bleomycin-injured WT mice on day 14. In contrast, the level of tissue inhibitor of metalloproteinases-1 (TIMP-1), an endogenous MMP-9 inhibitor, was increased in the bleomycin-treated eNOS-TG mice compared with WT. Immunohistochemical analysis demonstrated that MMP-9 and TIMP-1 were strongly expressed in inflammatory cells, including subpleural fibrotic lesions. CONCLUSION: These data suggested that eNOS overexpression attenuates bleomycin-induced lung injury by ameliorating the MMP-9/TIMP-1 balance.  相似文献   
997.
In almost all eukaryotes, mitochondrial (mt) genes are transmitted to progeny mainly from the maternal parent. The most popular explanation for this phenomenon is simple dilution of paternal mtDNA, because the paternal gametes (sperm) are much smaller than maternal gametes (egg) and contribute a limited amount of mitochondria to the progeny. Recently, this simple explanation has been challenged in several reports that describe the active digestion of sperm mtDNA, down-regulation of mtDNA replication in sperm, and proteolysis of mitochondria triggered by ubiquitination. In this investigation, we visualized mt nucleoids in living sperm by using highly sensitive SYBR green I vital staining. The ability to visualize mt nucleoids allowed us to clarify that the elimination of sperm mtDNA upon fertilization is achieved through two steps: (i) gradual decrease of mt nucleoid numbers during spermatogenesis and (ii) rapid digestion of sperm mtDNA just after fertilization. One notable point is that the digestion of mtDNA is achieved before the complete destruction of mitochondrial structures, which may be necessary to avoid the diffusion and transmission of potentially deleterious sperm mtDNA to the progeny.  相似文献   
998.
Angiotensin II is involved in the process of atherosclerosis and stimulates superoxide production from cardiovascular cells. We examined the effect of telmisartan, an angiotensin II type 1 receptor blocker, on atherosclerosis. We chronically treated apolipoprotein E-deficient mice with two different doses of telmisartan dissolved in drinking water (0.3 and 3 mg/kg) starting from 4 weeks of age for 12 weeks. Lipid contents were not different in both telmisartan-treated groups compared with control group. Systolic blood pressure was significantly reduced with 3 mg/kg, but unchanged with 0.3 mg/kg. The total atherosclerotic lesion size at the aortic sinus was reduced with 0.3 mg/kg compared with control, and additional reduction was proved with 3 mg/kg. The fibrotic change was not different among three groups, but MOMA-2-, malondialdehyde-, 4-hydroxy-2-nonenal-immunostained areas were reduced by telmisartan. As the mechanism, we revealed that both doses of telmisartan markedly reduced superoxide production from in situ vessels assessed by lucigenin-enhanced chemiluminescence and dihydroethidium staining. And NAD(P)H dependent oxidase activity in vessels was reduced by telmisartan. Further, 8-iso-prostaglandin F2alpha level, a systemic oxidative stress marker, obtained from urine and plasma samples were significantly reduced by telmisartan. Telmisartan reduced atherosclerosis in apolipoprotein E-deficient mice at least partly via the suppression of oxidative stress.  相似文献   
999.
Mutations of the epidermal growth factor receptor (EGFR), particularly deletional mutations (DEL) in exon 19 and L858R in exon 21, are reportedly correlated with clinical outcome in patients with non-small cell lung cancer (NSCLC) receiving the EGFR tyrosine kinase inhibitors gefitinib and erlotinib, suggesting that detection of EGFR mutations would have an important role in clinical decision making. We established and validated an easy, inexpensive, and rapid method for detecting DEL and L858R from cytologic material by high-resolution melting analysis (HRMA). Dilution for sensitivity studies revealed that DEL and L858R were detectable in the presence of at least 10% and 0.1% EGFR-mutant cells, respectively. We analyzed 37 archived cytological slides of specimens from 29 patients with advanced NSCLC and compared the results with direct sequencing data obtained previously. Of 37 samples, 34 (92%) yielded consistent results with direct sequencing, 2 were false negative, and 1 was indeterminate. The sensitivity of this analysis was 90% (19/21) and specificity, 100% (15/15). These results suggest that HRMA of archived cytologic specimens of advanced NSCLC is useful for detecting EGFR mutations in clinical practice.  相似文献   
1000.
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