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211.
Src, a proto-oncogene, has been strongly implicated in the growth, progression and metastasis of a number of human cancers. Its role in lung cancer is, however, still unknown. In the present study, we assessed the expression of Src in three different human lung adenocarcinoma cell lines (PC-9, PC14PE6, A549), and explored the effect of a novel Src kinase inhibitor, M475271, on the behavior of the cell lines. The three cell lines expressed various levels of auto-phosphorylated Src. While M475271 reduced Src-phosphorylation and invasiveness of all three cell lines, it inhibited the proliferation of PC-9 and A549 cells with highly phosphorylated Src, but not PC14PE6 cells. We further examined the effect of M475271 on subcutaneous tumors and lung metastasis caused by PC-9 and/or A549 cells in NK-cell depleted SCID mice. Daily oral treatment with M475271 inhibited the growth of subcutaneous tumors with PC-9 and A549 cells via inhibition of tumor cells proliferation, VEGF production and/or vascularization in the mice in a dose-dependent manner. In the metastasis model with A549 cells, the lung weight in the M475271 (50 mg/kg)-treated group was less than that of the control group, despite no difference in the number of metastatic nodules. Our results suggest that inhibition of tyrosine kinase Src by M475271 could reduce the growth, invasion and VEGF-mediated neovascularization of lung adenocarcinoma cells, resulting in inhibition of growth of subcutaneous tumors and lung metastasis. Therefore, a novel Src tyrosine kinase inhibitor, M475271, might be helpful for controlling the progression of human lung adenocarcinoma.  相似文献   
212.
BACKGROUND AND OBJECTIVES: It is important to identify the initial lymph node metastasis when performing less invasive surgery. The purpose of the present study was to analyze locations of solitary lymph node metastasis and micrometastasis in esophageal carcinoma. METHODS: We retrospectively analyzed the initial sites of lymph node metastasis in esophageal cancer. Sixty-five consecutive patients with solitary lymph node metastasis, and 33 pN0 patients with only lymph node micrometastasis detected by immunohistochemistry, were classified according to tumor location and tumor depth. RESULTS: The location of lymph node metastasis in the 22 patients with superficial cancer was limited to recurrent nerve nodes (RN) in the upper thoracic esophagus; RN, paraesophageal nodes (PE), or perigastric nodes (PG) in the middle or lower thoracic esophagus. Thirty-six patients with advanced cancer had lymph node metastasis at RN, PE, or PG locations, while in the remaining seven, lymph node metastasis was found in areas far from the primary tumor. Regarding the 33 patients with lymph node micrometastasis, the locations of micrometastasis were similar to those of solitary metastasis. CONCLUSIONS: Although less invasive surgery, such as reduction of lymphadenectomy, may be suitable for superficial cancer, it should be performed with special care in advanced cancer.  相似文献   
213.
To understand the possible roles of the hyaluronan synthetase (HAS)/hyaluronan (HA)/CD44 signaling system in the posterior eye segment, we investigated the expression of rabbit HAS isoforms and CD44 mRNA by RT-PCR and the level of HA by using HA assay and immunohistochemistry. HA was detectable in vitreous, retina and choroid. The expression of three HAS isoforms was clearly detected in both retina and choroids. Rabbit choroid showed a significant increase of the HAS2 and HAS3 expression compared with rabbit retina (HAS2 p = 0.0014 < 0.05; HAS3 p = 0.0006 < 0.05). Similarly, mRNA expression of CD44 was detected in both retina and choroids. This evidence may suggest that the HAS/HA/CD44 signaling system is important in maintaining the functional structure of retina and choroid.  相似文献   
214.
Background: The aim of this study was to identify the clinical characteristics of hospitalized children with the 2009 pandemic influenza virus infection in Japan. Methods: We retrospectively reviewed cases of hospitalized children younger than 16 years with laboratory‐confirmed influenza A virus infection during the 2009–2010 pandemic season in five hospitals in Japan. Results: A total of 515 cases were included in the analysis. The median age was 6.3 years (range 0–15), and 216 subjects (41.9%) had one or more underlying medical conditions. There were no fatalities, but 16 patients (3.1%) required intensive care. More than 93% of the subjects received neuraminidase inhibitors, and more than 87% received these medications within 48 h of the onset of symptoms. Approximately 80% of all subjects were admitted to hospital within 48 h of the onset of symptoms. Conclusions: There were no fatalities, and the proportion of patients with serious illness was substantially lower than previously reported from other countries. Good access to medical services and proactive treatment may have contributed to the lower disease burden of the 2009 influenza pandemic on Japanese children.  相似文献   
215.
Osteoclasts form ruffled borders and sealing zones toward bone surfaces to resorb bone. Sealing zones are defined as ringed structures of F-actin dots (actin rings). Polarized osteoclasts secrete protons to bone surfaces via vacuolar proton ATPase through ruffled borders. Catabolic enzymes such as tartrate-resistant acid phosphatase (TRAP) and cathepsin K are also secreted to bone surfaces. Here we show a simple method of identifying functional vestiges of polarized osteoclasts. Osteoclasts obtained from cocultures of mouse osteoblasts and bone marrow cells were cultured for 48 h on dentin slices. Cultures were then fixed and stained for TRAP to identify osteoclasts on the slices. Cells were removed from the slices with cotton swabs, and the slices subjected to TRAP and Mayer's hematoxylin staining. Small TRAP-positive spots (TRAP-marks) were detected in the resorption pits stained with Mayer's hematoxylin. Pitted areas were not always located in the places of osteoclasts, but osteoclasts existed on all TRAP-marks. A time course experiment showed that the number of TRAP-marks was maintained, while the number of resorption pits increased with the culture period. The position of actin rings formed in osteoclasts corresponded to that of TRAP-marks on dentin slices. Immunostaining of dentin slices showed that both cathepsin K and vacuolar proton ATPase were colocalized with the TRAP-marks. Treatment of osteoclast cultures with alendronate, a bisphosphonate, suppressed the formation of TRAP-marks and resorption pits without affecting the cell viability. Calcitonin induced the disappearance of both actin rings and TRAP-marks in osteoclast cultures. These results suggest that TRAP-marks are vestiges of proteins secreted by polarized osteoclasts.  相似文献   
216.
A 74-year-old man with nausea underwent upper gastrointestinal endoscopy, and a 0-IIb type tumor was found in the middle thoracic esophagus. Histological examination with endoscopic biopsies revealed squamous cell carcinoma (SCC), and chromoendoscopy with iodine staining revealed that the superficial SCC involved nearly the entire circumference of the esophageal lumen. There were neither nodal nor distant metastases. Complete circular endoscopic submucosal dissection (ESD) was successfully achieved with tumor-free margins in an en bloc fashion. The histopathological examination confirmed a diagnosis of intramucosal invasive carcinoma limited to the lamina propria mucosae without angiolymphatic invasion. Oral prednisolone was started with 0.5 mg/kg daily on the 3rd post-ESD day, tapered gradually, and then discontinued 8 weeks later without adverse effects. There were no complaints of dysphagia following ESD. On follow-up endoscopy with iodine staining, which was scheduled at 1, 3 and 6 months after ESD, there was no postprocedural esophageal stricture, and neither recurrent nor metachronous lesions were found. Thus, the patient required no sessions of endoscopic balloon dilatation. At the last outpatient clinic visit 7 months after ESD, he remained well without dysphagia. Oral prednisolone administration may offer an effective therapeutic strategy to prevent the post-ESD esophageal stricture after complete circular ESD.  相似文献   
217.
A 34-year-old female presented with an 8-year history of temporal lobe epilepsy. Magnetic resonance imaging showed a multilobular, well-demarcated and homogeneous tumorous lesion of 5 cm in diameter deep in the left sylvian fissure. Intraoperative findings revealed that the tumor was mainly in the left insular region without dural attachment and strongly adhered to the left middle cerebral artery and its perforators. The histopathological diagnosis was transitional meningioma without malignancy. There are few reported cases of deep sylvian meningioma without dural attachment. We review the literature and summarize the clinicopathological characteristics of this condition.  相似文献   
218.
219.
Purpose Flurbiprofen axetil emulsion (FA), a prodrug of nonsteroidal anti-inflammatory drugs (NSAIDs) that is widely used for perioperative pain relief in Japan, has been effective for reducing propofol injection pain, but the mechanism is unclear. The purpose of this study was to test the hypothesis that the reduction of propofol injection pain by FA may be attributed to a decrease in free propofol concentration. Methods Diprivan (propofol emulsion; Dipri; AstraZeneca, Cheshire, UK) and Propofol-Lipuro (Lipuro; B. Braun, Melsungen, Germany) were used. A randomized double-blind study was performed to compare pain on injection with six kinds of propofol solution: plain Dipri, a 3 : 1 (v/v) mixture of Dipri and saline (Dipri-S), a 3 : 1 mixture of Dipri and FA (Dipri-FA), plain Lipuro, a 3 : 1 mixture of Lipuro and saline (Lipuro-S), and a 3 : 1 mixture of Lipuro and FA (Lipuro-FA). Three hundred patients (American Society of Anesthesiologists [ASA] physical status [PS] I–II) scheduled for elective surgery received one of these six propofol emulsions (n = 50, each group). Injection pain was evaluated every 10 s after the start of a 1-min infusion of up to 2 mg·kg−1 propofol. We also measured the in vitro free propofol concentrations of the propofol preparations that we tested (n = 5, each). Results The mixture of FA with propofol decreased the incidence of injection pain, compared with plain propofol, for Lipuro (P < 0.01) but not for Dipri. The free propofol concentration in each emulsion in vitro was also decreased by mixing the propofol with saline or FA. The incidence of pain was reduced in a free-propofol concentration-dependent manner (R2 = 0.926). Conclusion The findings suggest that the reduction of propofol injection pain by FA may be explained, at least in part, by a reduction in the free propofol concentration.  相似文献   
220.
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