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81.
We investigated the biological properties of a novel staphylococcal enterotoxin (SE)-like toxin type P (SElP). SElP induced a substantial proliferative response and the production of cytokines interleukin-2, gamma interferon, tumor necrosis factor alpha, and interleukin-4 from human T cells when administered at a concentration of 0.4 pM (0.01 ng/ml) or more. The expression of major histocompatibility complex class II molecules on accessory cells was required for T-cell stimulation by SElP. SElP selectively stimulated a vast number of human T cells bearing receptors Vbeta 5.1, 6, 8, 16, 18, and 21.3. These results indicated that SElP acts as a superantigen. SElP proved to be emetic in the house musk shrew emetic assay, although at a relatively high dose (50 to 150 mug/animal). A quantitative assay of SElP production with 30 Staphylococcus aureus strains harboring selp showed that 60% of these strains produced significant amounts of SElP in vitro. All 10 strains carrying seb and selp produced SEB but not SElP, suggesting the inactivation of the selp locus in S. aureus strains with a particular se gene constitution.  相似文献   
82.
83.
Safe techniques in surgery for hysteroscopic myomectomy   总被引:1,自引:0,他引:1  
Hysteroscopic myomectomy is regarded as the best treatment for patients with submucous myomata. However, this procedure has a number of associated complications, including uterine perforation, cervical laceration, hyponatremia and hemorrhage, especially in cases of sessile submucous myomata. To avoid these problems, it is important to make well-advised preparations and manipulations both pre- and intraoperatively. The main surgical considerations for safe hysteroscopic myomectomy are shortening the operating time and avoiding cutting too deeply into the myometrium. With these requirements in mind, a combination of techniques using vaporization and a powerful oxytocic agent, such as prostaglandin F-2alpha, appears to be the safest method of carrying out hysteroresectoscopy for unpedunculated sessile submucous myomata.  相似文献   
84.
Diabetic nephropathy is one of the major microvascular complications in diabetes and is the leading cause of end-stage renal disease worldwide. Among various factors, angiogenesis-associated factors such as vascular endothelial growth factor (VEGF)-A and angiopoietin (Ang)-2 are involved in the development of diabetic nephropathy. We previously reported the therapeutic efficacy of antiangiogenic tumstatin peptide in the early diabetic nephropathy model. Here, we examine the effect of endostatin peptide, a potent inhibitor of angiogenesis derived from type XVIII collagen, in preventing progression in the type 1 diabetic nephropathy mouse model. Endostatin peptide did not affect hyperglycemia induced by streptozotocin (STZ). Glomerular hypertrophy, hyperfiltration, and albuminuria were significantly suppressed by endostatin peptide (5 mg/kg) in STZ-induced diabetic mice. Glomerular mesangial matrix expansion, the increase of glomerular type IV collagen, endothelial area (CD31(+)), and F4/80(+) monocyte/macrophage accumulation were significantly inhibited by endostatin peptide. Increase in the renal expression of VEGF-A, flk-1, Ang-2, an antagonist of angiopoietin-1, transforming growth factor-beta1, interleukin-6, and monocyte chemoattractant protein-1 was inhibited by endostatin peptide in diabetic mice. Decrease of nephrin mRNA and protein in diabetic mice was suppressed by treatment with endostatin peptide. The level of endostatin in the renal cortex and sera was increased in diabetic mice. Endogenous renal levels of endostatin were decreased in endostatin peptide-treated groups in parallel with VEGF-A. Although serum levels of endostatin were decreased in the low-dose endostatin-peptide group, high-dose administration resulted in elevated serum levels of endostatin. These results demonstrate the potential use of antiangiogenic endostatin peptide as a novel therapeutic agent in diabetic nephropathy.  相似文献   
85.
Nandate K  Ogata M  Tamura H  Kawasaki T  Sata T  Shigematsu A 《Anesthesia and analgesia》2005,100(5):1453-7, table of contents
Leukocyte adhesion to endothelial cells plays a pivotal role in the early stage of endotoxin shock. The attenuation of the leukocyte response to endotoxin may contribute to the prevention of further organ dysfunction. Recent evidence implies that N-acetyl-cysteine (NAC) attenuates endotoxin-induced pathophysiological changes. We investigated the effect of NAC on the expression of CD11b and CD62L in endotoxin-stimulated human whole blood. NAC (>10 mM) significantly inhibited the lipopolysaccharide (LPS)-induced upregulation of CD11b in a concentration-dependent manner. However, NAC did not affect the LPS-induced downregulation of CD62L. We also analyzed the effect of NAC on interleukin-8 (IL-8)-induced expression of CD11b in human whole blood. IL-8 (10 ng/mL) significantly upregulated the expression of CD11b, and the IL-8-induced upregulation was significantly attenuated by NAC (>10 mM) in a dose-dependent manner. We conclude that NAC attenuates the increased expression of CD11b in either LPS or IL-8-stimulated human whole blood.  相似文献   
86.
Two cases of spontaneous cholesterol embolism, which followed different clinical courses, acute and chronic renal failure, are presented and histopathological lesions are compared. Both cases were diagnosed as cholesterol embolism post-mortem. Case 1 (a 66-year-old man) had acute onset of illness with fever, leucocytosis and renal failure, diagnosed as vasculitis, and died of rupture of an abdominal aortic aneurysm. Case 2 (an 84-year-old man) had eosinophilia of unknown aetiology for 7 years with intermittent worsening of renal function and died of sepsis. Case 1 had diffuse cholesterol crystal emboli in the interlobular arteries and arterioles of the kidney, but case 2 had patchy cholesterol emboli in the interlobular arteries of the kidney. The aorta of case 1 was diffusely ulcerated, which is in contrast to that of case 2, who had limited ulceration in thoracic aorta, which might have contributed to the long duration of illness. Immunohistochemically, the number of macrophages and T cells that infiltrated around cholesterol emboli in the arteries was more in case 1 (macrophages 27.7, T cells 36.1/mm(2)) than in case 2 (2.7, 1.38/mm(2)). Focal interstitial inflammation occurred in both cases. In case 1, marked tubulitis was observed. Case 2 had rather severe atrophy of the tubules and fibrotic interstitium where mast cells were rich (31.9/mm(2)). The number of B cells and eosinophils was few in case 2 (11.35, 0.7/mm(2)) compared with case 1 (101.9, 16.15/mm(2)). These results suggest that in acute lesions of renal cholesterol embolism, macrophages and T cells accumulate around cholesterol crystals and cause tubulointerstitial inflammatory lesions with other inflammatory cells. In chronic lesions, macrophages, T cells and mast cells are the major inflammatory cells present in the interstitium.  相似文献   
87.
Many molecular factors related to the carcinogenesis and malignant behavior of pancreatic cancer were identified by investigation of intraductal papillary mucinous tumors (IPMTs). Molecules controlling the G1/S phase, such as p53, p21, p61, and cyclin D1, tumor suppressors including DPC-4, and many other factors such as MUC-1/2 contribute to the promotion of the malignant behavior of IPMTs. They will be important molecular targets for the radical treatment of pancreatic cancer.  相似文献   
88.
Introduction A 64-year-old woman presented with symptoms of subacute exacerbation of a year-long carpal tunnel syndrome that was caused by a large calcified mass in the tunnel.Conclusion The resected mass consisted of very tiny rods, and x-ray diffraction analysis, as well as the component analysis using energy dispersive x-ray microanalysis, revealed the mass to be most compatible with apatite. The back-scattered electron images suggested that precipitation might be a mechanism for development of the calcified mass.  相似文献   
89.
Bacterial control in poultry processing plants is very important, but the swab method for estimating bacterial contamination is somewhat troublesome in routine work. We compared the Desoxycholate Agar Nissui Food Stamp (DA-NFS) based on the agar contact method with the swab method to estimate coliform organisms from various equipments in four poultry processing plants after cleaning. Overall 104 surfaces for coliform organisms were evaluated. The results from 98 (94.2%) surfaces for coliform organisms were equivalent by the DA-NFS and swab methods and there were no significant differences between two methods (P > 0.05). The correlation coefficient between the DA-NFS and swab methods was 0.91. We conclude that the DA-NFS could be useful for routine coliform organisms examination in poultry processing plants after cleaning in Japan.  相似文献   
90.
OBJECTIVE: To investigate the effects of 17beta-estradiol (E(2)) on cyclooxygenase-2 (COX-2) expression and prostaglandin E(2) (PGE(2)) synthesis in primary human uterine microvascular endothelial cells (HUMEC). DESIGN: Prospective study. SETTING: Basic research laboratory at an academic medical center. PATIENT(S): Primary HUMEC of three women donors and primary human dermal microvascular endothelial cells of three women donors (as control), purchased from a third-party source. INTERVENTION(S): The HUMEC were cultured in specific media in a humidified atmosphere with 5% CO(2) at 37 degrees C. MAIN OUTCOME MEASURE(S): Measures of COX-2 mRNA and protein, PGE(2) production, and estrogen receptor alpha and beta mRNA and protein. RESULT(S): Treatment with E(2) (10(-10) to 10(-6) M) increased COX-2 mRNA levels by 2.3-fold to 2.4-fold in HUMEC. Treatment of HUMEC with E(2) (10(-8) M) resulted in a time-dependent increase of COX-2 mRNA levels. This was accompanied by a 2.8-fold increase in COX-2 protein level and a 1.5-fold increase in PGE(2) synthesis. Pretreatment of HUMEC with a selective COX-2 inhibitor, NS-398, abolished E(2)-induced PGE(2) synthesis, suggesting that E(2) specifically up-regulates COX-2 activity. The estrogen receptor antagonist ICI 182,780 fully reversed the stimulation of COX-2 mRNA and protein levels and PGE(2) synthesis by E(2). Interestingly, estrogen receptor beta mRNA and protein were abundant in HUMEC, whereas estrogen receptor alpha mRNA or protein was barely detectable. CONCLUSION(S): We conclude that various levels of E(2) can significantly increase COX-2 expression and PGE(2) synthesis in HUMEC via the estrogen receptor.  相似文献   
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