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991.
Yoo K  Woo OH  Yong HS  Kim A  Ryu WS  Koo BH  Kang EY 《Surgery today》2007,37(11):967-970
Pseudoangiomatous stromal hyperplasia (PASH) is a rare type of benign mesenchymal proliferative disease of the breast. Histologically, it is composed of a proliferation of spindle cells with inter-anastomosing vascular-like arrangement in the interlobular or interductal stroma. Clinically, pseudoangiomatous stromal hyperplasia is usually found in premenopausal women as a discrete, painless mass, which is firm and movable. We report a case of pseudoangiomatous stromal hyperplasia of the breast, which mimicked a malignant mass in that it grew rapidly and ultrasonography showed a lobulating contoured heterogeneous echotexture.  相似文献   
992.
Tendency of isolated bacteria from infections in abdominal surgery during the period from April 2005 to March 2006 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 384 strains including 18 strains of Candida spp. were isolated from 161 (70.3%) of 229 patients with surgical infections. One hundred and ninty-five strains were isolated from primary infections, and 171 strains were isolated from postoperative infections. From primary infections, aerobic Gram-negative bacteria and aerobic Gram-positive bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Pseudomonas aeruginosa, Klebsiella spp. in this order, and from postoperative infections, E. coli was the most predominantly isolated, followed by Klebsiella pneumoniae and P. aeruginosa. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both primary and postoperative infections. In this series, we noticed no vancomycin-resistant Gram-positive cocci, nor multidrug-resistant P. aeruginosa. But cefazolin-resistant E. coli producing extended spectrum fl-lactamase was seen in 5.0 per cents. We should be carefully followed up the facts that the increasing isolation rates of B. fragilis group and Bilophila wadsworthia which were resistant to both penicillins and cephems.  相似文献   
993.
The preventive effect of Anemarrhena asphodeloides Bunge (Liliaceae), a traditional Chinese medicine, on ischemia-reperfusion-induced brain injury was evaluated in the rat brain. Ischemia was induced by intraluminal occlusion of the right middle cerebral artery for 2 h and reperfusion was continued for 22 h. Water extract of Anemarrhena asphodeloides (WEAA) was orally administered promptly prior to and 2 h after reperfusion. Total infarct volume and edema in the ipsilateral hemispheres of ischemia-reperfusion rats were significantly reduced by treatment with WEAA in a dose-dependent manner (p<0.05). The therapeutic time window of WEAA was 3 h in this ischemia-reperfusion rat model. WEAA also significantly inhibited increased neutrophil infiltration of ischemic brain tissue as estimated by myeloperoxidase (MPO) activity and immunohistochemical analysis. MPO-positive cells were markedly reduced by WEAA administration in striatal and cortical areas. These findings suggest that WEAA plays a crucial protective role in ischemia-induced brain injury, and suggest that WEAA could serve as a lead medicinal herb for the development of neuroprotective agents following transient focal ischemic brain injury.  相似文献   
994.
We examined the source of Ca(2+) involved in the volume regulation of Madin-Darby canine kidney (MDCK) cells with confocal microscopy and fluoroprobes. Hyposmosis induced a transient increase in cell volume, as well as cytoplasmic Ca(2+), which peaked at 3 to 5 min and gradually decreased to reach the initial value within about 30 min. This late decrease in cell volume, as well as the transient rise in cytoplasmic Ca(2+), was reduced in Ca(2+)-free solution and was abolished by pretreatment with thapsigargin. In conclusion, Ca(2+) released from the intracellular store contributes to the regulatory volume decrease following hyposmotic swelling in MDCK cells.  相似文献   
995.
In spite of their pathophysiological importance in neuro-inflammatory diseases, little is known about the signal transduction pathways that lead to the induction of matrix metalloproteinases (MMPs) in the central nervous system. We reported previously that lipopolysaccharide (LPS) induced MMP-9 expression through ERK1/2 pathway in rat primary astrocytes (Glia 41:15-24, 2003). Here, we investigated the role of other MAPK pathways, including p38 and JNK/SAPK, on the regulation of MMP-9 expression in LPS-stimulated rat primary astrocytes. LPS activated both p38 and JNK in astrocytes. Treatment with a specific p38 MAPK inhibitor SB203580, but not JNK inhibitor SP600125, increased the LPS-stimulated MMP-9 expression in a concentration-dependent manner. Anti-inflammatory cytokines, including IFN-gamma and IL-4, activated p38 MAPK and decreased MMP-9 production in LPS-stimulated astrocytes. When p38 MAPK activation was blocked by SB203580, the inhibitory effects of these cytokines on MMP-9 induction were abolished. Finally, direct injection of SB203580 into the lateral ventricle of rat brain increased the LPS-induced MMP-9 activity in cerebral cortex. Altogether, these results suggest that p38 activation down-regulates the inflammatory stimulation-induced overexpression of MMP-9, both in primary astrocytes and in cerebral cortex. The elaborate interplay between ERK1/2 and p38 pathways provides a more sophisticated mechanism for regulating MMP-9 activity in neuroinflammatory diseases.  相似文献   
996.
The effects of prenatal and postnatal lead exposure on monoamine oxidase (MAO) activity were investigated in rat brain. MAO activity was examined in 2, 4, 6, and 8 weeks old rat to investigate the effects of lead in the different stages of rat brain development. Prenatal lead exposure was achieved by providing mother rats with drinking water containing either low (0.05%) or high (0.2%) concentration of lead acetate from gestation to birth. Postnatal lead treatment was performed through drinking water to mothers and pups from birth to the day of experiment. MAO activity was gradually increased with the development in all the brain regions examined, i.e. telencephalon, diencephalons, midbrain, pons/medulla, and cerebellum. Lead exposure increased MAO activity in most of the brain regions especially at early developmental stages (2 weeks of age) and the toxicity was gradually decreased with the development of rats. High concentration of lead showed greater effects on MAO activity compared to low concentration. Postnatal lead exposure showed stronger effects on MAO activity compared to prenatal lead exposure demonstrating the importance of preventing lead exposure to lactating mother. The increased MAO activity by lead intoxication may contribute to the neurobehavioral changes such as cognitive and attention deficit as well as hyperactivity, which is commonly observed both in lead intoxication and perturbed monoaminergic neurotransmission.  相似文献   
997.
998.
Background/Aims: Serum creatinine (Cr) is not a reliable marker for early detection of renal dysfunction in patients with cirrhotic ascites. Several reports have suggested that cystatin C (CysC) is more sensitive than Cr for detecting reduced renal function in these patients. This study evaluated the clinical significance of CysC in patients with cirrhotic ascites and a normal serum Cr level. Methods: We enrolled patients with ascites and a normal serum Cr level (<1.2 mg/dl). Liver function tests, international normalized ratio (INR) and serum Cr and CysC levels were measured on the same day for all patients. CysC levels were measured using the automated latex‐enhanced immunonephelometric method. The endpoint of follow‐up was the development of hepatorenal syndrome (HRS) or mortality. Results: Seventy‐eight patients with cirrhotic ascites were enrolled in the study (58 men and 30 women; age, 53±11 years). The underlying liver diseases in these patients were chronic hepatitis B (37%), chronic hepatitis C (4%), alcoholic liver disease (53%) and others (6%). Forty‐six (59%) and 32 (41%) patients were in Child–Pugh classes B and C respectively. HRS developed in 14 patients during the follow‐up period (349±241 days), with cumulative incidences of 10.2% and 20.4% at 6 and 12 months respectively. The CysC level was the only independent predictive factor for HRS. Twenty‐three patients died during the follow‐up period. CysC level and INR were independent factors for predicting mortality. Conclusion: Serum CysC level is a good marker for predicting HRS and survival in patients with cirrhotic ascites and a normal Cr level.  相似文献   
999.
Background and Aim:  Although endoscopic papillectomy has been attempted in early stage ampullary cancer (pTis, T1), its curative role and indications remain uncertain. The present study was designed to assess the factors that predict malignancy and lymph node metastasis and to suggest potential indications for endoscopic papillectomy by analyzing clinicopathological data.
Methods:  We performed a retrospective analysis of clinical and histopathological data of 216 patients with ampullary cancer between 1991 and 2006.
Results:  No tumor in pTis stage had metastasized to lymph nodes and only 9% of tumors in pT1 had metastasized. Tumor size ( P  = 0.018), depth of invasion ( P  = 0.021) and venous invasion ( P  = 0.014) were found to be significantly related to lymph node metastasis. Cases with early stage ampullary cancer of less than 2 cm with a well-differentiated histology and no angiolymphatic invasion ( n  = 13) showed no lymph node metastasis and no recurrence during a median follow up of 35.9 months.
Conclusion:  Endoscopic papillectomy can be adopted as a viable alternative to surgery in patients with early stage ampullary cancer of less than 2 cm in size and with a well-differentiated histology. When a resected specimen has a well-differentiated histology, and there is no resection margin involvement and no angiolymphatic invasion, our findings indicate that subsequent radical surgery is unnecessary.  相似文献   
1000.
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