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11.
Apoptotic cell death in acinar and ductal epithelial cells is thought to play an important role in the development of salivary gland dysfunction in patients with Sjogren's syndrome (SS). We examined the expression of anti-apoptotic molecules in salivary glands from patients with SS. The labial salivary glands from six human T-cell leukemia virus (HTLV)-I-seronegative and eleven HTLV-I-seropositive SS patients were analyzed by immunohistochemistry. In vitro experiments were performed with a human salivary gland cell line (HSG cells). Immunohistologic analyses revealed that Bcl-2 and Bcl-x were preferentially expressed in salivary infiltrating mononuclear cells more than acinar and ductal epithelial cells. In contrast, strong X chromosome-linked inhibitor of apoptosis protein (XIAP) expression was evident in both acinar and ductal epithelial cells. The pattern of expression of these anti-apoptotic molecules was similar in both HTLV-I-seropositive and HTLV-I -seronegative SS patients. Western blot analysis confirmed expression of XIAP in cultured HSG cells. The expression of XIAP in HSG cells was increased by IL-1beta, TGF-beta1, or IL-10. However, XIAP expression was down-regulated by TNF-alpha, which induced apoptotic cell death of HSG cells with an increase in caspase-3 activity. These effects of TNF-alpha in HSG cells were antagonized by IL-1beta, TGF-beta1, or IL-10. Our results suggest that XIAP is important in regulating apoptotic cell death of acinar and ductal epithelial cells in patients with SS.  相似文献   
12.
Leflunomide, an isoxazol derivative structurally unrelated to other immunomodulatory drugs, has proven to be efficacious in the treatment of rheumatoid arthritis (RA). This study was conducted to elucidate the mechanism by which leflunomide mediated antirheumatic effects. We investigated the effects of A77 1726, leflunomide's active metabolite, on mitogen-activated protein kinase (MAPK) activation in IL-1beta-stimulated rheumatoid synovial fibroblasts. The effects of A77 1726 on the secretion of matrix metalloproteinases (MMPs) from rheumatoid synovial fibroblasts were also examined. A77 1726 partially suppressed IL-1beta-induced ERK1/2 and p38 kinase activation. In contrast, A77 1726 efficiently suppressed IL-1beta-stimulated JNK1/2 kinase activation. Although no suppressive effect was demonstrated on MMP-2, A77 1726 markedly inhibited MMP-1, 3, and 13 secretions from IL-1beta-stimulated rheumatoid synovial fibroblasts. Tissue inhibitor of metalloproteinases-1 (TIMP-1) was constitutively produced from rheumatoid synovial fibroblasts and the suppressive effects of A77 1726 on TIMP-1 production were minimal. Our results suggest that the suppression of the MAPK signalling pathway and MMP synthesis in rheumatoid synovial fibroblasts is a possible mechanism for the inhibitory activity of leflunomide against rheumatoid arthritis.  相似文献   
13.
Renal osteodystrophy (ROD) accompanied by long-term hemodialysis patients with chronic renal failure includes several forms of disorders of mineral and skeletal metabolism such as osteitis fibrosa attributed to secondary hyperparathyroidism, osteomalasia and adynamic bone disease. Bone scan is performed to detect of the mainly pathophysiology of ROD. We investigated bone scan of 25 hemodialysis patients with secondary hyperparathyroidism diagnosed clinically before and after parathyroidectomy (PTX). Before PTX an diffusely high accumulation of bone seeking agent in the whole skeleton especially skull in all patients (100%), vertebra in 24 out of 25 (96%), patella in 24/25 (96%), limbs in 23/25 (92%), sternum in 19/25 (76%), sacrum in 18/25 (72%) and costochondral junctions in 14/25 (56%) was noted in these patients. The radionuclide activity of the calvaria, maxilla and mandible in the skull was prominently high. Fourteen patients had an equally high activity in the calvaria, maxilla and mandible, 6 patients had higher activity in the maxilla and mandible than that of calvaria and 5 patients had higher in the calvaria than that of maxilla and mandible. After PTX the changes in the skull were obvious in 19 patients who showed a more markedly decreased in activity of the maxilla and mandible than that of the calvaria. In 3 patients showed a more markedly decreased in activity of the calvaria than that of the maxilla and mandible. Another 3 demonstrated equally decreased in activity in the calvaria, maxilla and mandible. It became clear that the highest activity of the skull was shown in all patients and the therapeutic changes of the skull are the most pronounced in maxilla and mandible in this study.  相似文献   
14.
Systemic capillary leak syndrome   总被引:2,自引:0,他引:2  
A 40-year-old woman was referred to our hospital with severe hypovolemic shock and anasarca. The laboratory findings showed marked hemoconcentration and a decrease in total serum protein with the presence of monoclonal IgG-lambda. She had had a similar episode of generalized edema 2 years previously. We diagnosed the patient as having typical systemic capillary leak syndrome (SCLS) and she improved gradually after infusion of albumin-containing fluid. SCLS is a very rare condition caused by unexplained episodic capillary hyperpermeability. Its treatment has remained largely supportive and the prognosis is generally poor. Awareness of SCLS is necessary for improvement of the outcome.  相似文献   
15.
OBJECTIVES: Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) has become established in the diagnosis of pancreatic cancer. The combination of pathological diagnosis and analysis for mutant K-ras gene was investigated to improve the accuracy of diagnosis. METHODS: EUS-FNA was performed in 34 patients with pancreatic masses (26 adenocarcinomas and eight chronic pancreatitis). Mutant ras gene was analyzed semiquantitatively in the specimens obtained by EUS-FNA as well as in pancreatic juice obtained by ERCP. RESULTS: Mutant gene was detected at high amounts (more than 2% of total ras genes) in 20 of 26 (77%) specimens of EUS-FNA and in 12 of 19 (63%) of pancreatic juice in cases with pancreatic carcinoma. Cytological diagnosis of malignancy by EUS-FNA was found in 16 of 26 (62%) patients with pancreatic cancer. Accurate diagnosis of the carcinoma was 21 of 26 (81%) by combined cytology and molecular method of EUS-FNA, and increased to 23 of 26 (88%) by adding molecular analysis of pancreatic juice. In contrast, mutant gene was absent or low level despite suspicious cytology in patients with benign pancreatic lesion. CONCLUSION: Quantitative analysis of mutant ras gene supplemented conventional cytology of EUS-FNA and ERCP. Detection of mutation at high amounts may represent pancreatic cancer, whereas its absence increased the possibility of benign lesion.  相似文献   
16.
The prevalence of antibodies to human T lymphotropic virus type I (HTLV-I) was studied in patients with primary Sjögren''s syndrome. Thirteen of 36 serum samples were positive by enzyme linked immunosorbent assay (ELISA) and particle agglutination assay for antibodies to HTLV-I and were confirmed by western blotting. The presence of antibodies to HTLV-I may signify an HTLV-I carrier state. These patients had a high occurrence of extraglandular manifestations such as uveitis, myopathy, and recurrent high fever compared with patients who did not have antibodies to HTLV-I. Patients with antibodies to HTLV-I had an increased spontaneous proliferation of peripheral blood mononuclear cells compared with those without the antibodies. The proportions of activated and memory T cells (HLA-DR+ CD3+, CD25+ CD3+, and CD29+ CD4+ cells) were higher in HTLV-I carriers than in non-carriers. The presence of antibodies to HTLV-I in some patients with primary Sjögren''s syndrome suggests that HTLV-I may cause primary Sjögren''s syndrome or its extraglandular manifestations, or both.  相似文献   
17.
Effect of L-dopa in young patients with hypertension   总被引:1,自引:0,他引:1  
The effects of L-dopa on blood pressure, heart rate, plasma renin activity, norepinephrine, epinephrine and prolactin were studied in a randomized single-blind trial in 36 patients with essential hypertension. In response to L-dopa, 250 mg administered orally, the blood pressure decreased significantly as compared with the results of placebo treatment. The heart rate and plasma norepinephrine and epinephrine were unchanged. The plasma renin activity and prolactin decreased as a result of L-dopa administration. The administration of a peripheral DA2 dopamine receptor blocker, domperidone (20 mg, orally) prevented the L-dopa-induced reduction in plasma prolactin but failed to block the fall in blood pressure and plasma renin activity. These results suggest that the blood pressure-lowering effect of L-dopa may be mediated through multiple sites involving D1 dopamine receptors, the central nervous system, and the renin-angiotensin system.  相似文献   
18.
Mutations in the cardiac Na+ channel gene SCN5A are responsible for multiple lethal ventricular arrhythmias including Brugada syndrome and congenital long QT syndrome. Here we report a case of Brugada syndrome with ST elevation in the right precordial and inferior leads accompanied by atrial standstill and spontaneous ventricular fibrillation. Atrial standstill and J wave elevation were provoked by procainamide. Genetic analysis revealed a missense mutation (R367H) in SCN5A. The resultant mutant Na+ channel was nonfunctional when expressed heterologously in Xenopus oocytes. Our study suggests that genetic defects in SCN5A may be associated with atrial standstill in combination with ventricular arrhythmias.  相似文献   
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