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71.
The aim of this study was to estimate the histologic type of invasive ductal carcinoma of the breast according to the ultrasound (US) criteria and to identify the high-risk patients for lymph node metastases. An acceptable preoperative diagnosis of lymph node metastasis is essential when performing the reduction of lymphadenectomy. The positive relationship between histology and prognosis has been reported in breast cancer. However, few reports have examined the relationship between preoperative US findings and histology. Ultrasound examination was performed in 252 patients with invasive ductal carcinoma (91 papillotubular, 54 solid-tubular and 107 scirrhous carcinoma). Risk factors for nodal metastasis were analyzed in clinicopathological findings. After nine criteria were defined based on US findings, all tumors were classified into US histologic type. According to the multivariate analysis, lymph node metastases was significantly associated with tumor size (p < 0.001), histology (p < 0.001) and age (p = 0.038). Histology was an important risk factor for nodal metastasis, especially in scirrhous carcinoma. When comparing the US classification and histology, the accuracy rate of US for papillotubular, solid-tubular and scirrhous type was 75%, 78% and 75%, respectively. To predict the scirrhous carcinoma with frequent nodal metastasis, US criteria such as the larger ratio of depth-to-width, boundary echo and attenuation of the back echo was important. It is important to preoperatively estimate the histologic type by tumor property using US. Our US classifications may be useful to pick up high-risk patients for nodal metastasis in invasive breast cancer.  相似文献   
72.
A patient with a reversible protruded lesion regarded as idiopathic appendiceal intussusception was investigated in this study. The patient was a 78‐year‐old male, who consulted our department as a result of positive occult blood in his stool sample. There was no associated pain, nausea, vomiting, fever, chill or anorexia. He had no prior surgical history. Total colonoscopy detected a sigmoidal polyp and a protruded lesion in the caecum. The protruded lesion (about 12 mm in diameter) covered with normal mucosa was diagnosed as a benign submucosal tumor at that time. The periodic follow‐up colonoscopy showed an orifice on top of the protuberance. Further detailed observation revealed that the lesion reduced by itself, and resulted in showing a normal orifice of the appendix; however, afterwards it protruded again. These observations led to the diagnosis of the lesion as type B of Atkinson's classification in appendiceal intussusception. To our knowledge, approximately 200 cases of appendiceal intussusception have been documented in scientific reports worldwide. In Japan, only 10 cases of idiopathic appendiceal intussusception have been described. This case is considered to be important for presenting the initial stage of the complete intussusception of the appendix.  相似文献   
73.
OBJECTIVE: To evaluate the efficacy of ultrasonography for the diagnosis of cervical lymph node metastasis in esophageal carcinoma. SUMMARY BACKGROUND DATA: Ultrasound (US) examination is useful for diagnosing lymph node metastasis. However, few reports have examined its role in the decision to perform cervical lymph node dissection in esophageal carcinoma. METHODS: Ultrasound examination was performed to evaluate cervical lymph node metastasis in 519 patients with esophageal carcinoma. The patients were divided into 5 groups according to treatment received: group 1, 153 patients who underwent curative resection of primary tumor by right thoracotomy and complete bilateral cervical lymphadenectomy; group 2, 112 patients who underwent curative resection of primary tumor by right thoracotomy but without cervical lymphadenectomy; group 3, 78 patients who underwent esophagectomy by left thoracotomy or blunt dissection with or without removal of cervical lymph nodes; group 4, 76 patients with palliative resection without cervical lymphadenectomy; and group 5, 100 patients without any surgical treatment. US diagnosis was compared with histologic findings or cervical lymph node recurrence. RESULTS: Lymph node metastasis was detected in 30.8% of patients (160/519). The sensitivity, specificity, and accuracy of US diagnosis in group 1 were 74.5%, 94.1%, and 87.6%, respectively. Cervical lymph node recurrence was seen in 7 patients (4.6%) in group 1, in 4 patients (3.6%) in group 2, and 3 patients (3.8%) in group 3. Although the incidence of cervical lymph node metastasis as determined by US examination was high in groups 4 and 5, almost none of the patients died of cervical lymph node metastasis. CONCLUSIONS: Ultrasound examination plays a useful role in the decision to perform cervical lymph node dissection in patients with esophageal carcinoma, particularly in those with potentially curative dissection.  相似文献   
74.

Background  

Limited gastrectomy for early gastric body cancers can offer a better functional outcome by preserving more remnant stomach. Intracorporeal stapled techniques result in cosmesis and avoid awkward anastomosis through a minilaparotomy.  相似文献   
75.
BACKGROUND: Acyl-coenzyme A:cholesterol O-acyltransferase-1 (ACAT-1), a major ACAT isozyme in macrophages, plays an essential role in foam cell formation in atherosclerotic lesions. However, whether pharmacological inhibition of macrophage ACAT-1 causes exacerbation or suppression of atherosclerosis is controversial. METHODS AND RESULTS: We developed and characterized a novel ACAT inhibitor, K-604. The IC(50) values of K-604 for human ACAT-1 and ACAT-2 were 0.45 and 102.85 micromol/L, respectively, indicating that K-604 is 229-fold more selective for ACAT-1. Kinetic analysis indicated that the inhibition was competitive with respect to oleoyl-coenzyme A with a K(i) value of 0.378 micromol/L. Exposure of human monocyte-derived macrophages to K-604 inhibited cholesterol esterification with IC(50) of 68.0 nmol/L. Furthermore, cholesterol efflux from THP-1 macrophages to HDL(3) or apolipoprotein A-I was enhanced by K-604. Interestingly, administration of K-604 to F1B hamsters on a high-fat diet at a dose of >or=1mg/kg suppressed fatty streak lesions without affecting plasma cholesterol levels. CONCLUSIONS: K-604, a potent and selective inhibitor of ACAT-1, suppressed the development of atherosclerosis in an animal model without affecting plasma cholesterol levels, providing direct evidence that pharmacological inhibition of ACAT-1 in the arterial walls leads to suppression of atherosclerosis.  相似文献   
76.
BCT (breast conserving therapy) has become a standard strategy for breast cancer and ensures local control and acceptable cosmetic results. However, an insufficient resection margin may increase local recurrence if too much attention is paid to cosmesis. Here, we describe a simple technique for reconstruction of the defect on the outer upper part of the breast with early breast cancer using thoracodorsal adipofascial flap.  相似文献   
77.
Ultrasound (US)-mediated gene transfection in the presence of microbubbles is a recently developed and promising non-viral gene delivery method. Optimising the parameters used in ultrasonic transfection is urgently required in order to realise higher transfection efficiencies in clinical settings. This study examined the effect of ultrasound exposure parameters on plasmid DNA transfection in mouse embryonic fibroblast cell lines using perfluorobutane bubbles. Variations in US intensity (0-11?W/cm2), pulse repetition frequency (PRF, 50-50,000?Hz), duty ratio (10 to 50%), exposure time (0-120?s) and microbubble volume concentration (0 to 10%) were tested, and the microbubble volume concentration was also monitored during exposure. Through the experiments, the mechanism of how variations in parameters influence US-mediated gene transfection was discussed, which can provide a basis for future applications of ultrasound mediated transfection.  相似文献   
78.
To reveal the role of oncogenes in Epstein-Barr virus (EBV)-positive gastric carcinomas, the amplification and overexpression of the c-met gene were examined by a competitive polymerase chain reaction and immunohistochemistry, respectively. The proportion of c-met amplification and overexpression in EBV-positive and -negative carcinomas did not differ significantly. The amplification and overexpression of the c-met gene in EBV-negative gastric carcinomas were significantly associated with upper location, deeper invasion and lymphatic invasion, while in EBV-positive gastric carcinomas a significant correlation with c-met activation was observed only in deeper invasion. However, none of the observed associations of c-met amplification or overexpression with clinicopathological features in the EBV-positive and -negative carcinomas differed significantly in their strength or direction. These results suggest that the amplification and overexpression of c-met gene do not play a different role in the progression and metastasis of EBV-positive and EBV-negative gastric carcinomas.  相似文献   
79.
BACKGROUND: To reduce the ambient concentration of waste anesthetic agents, exhaust gas scavenging systems are standard in almost all operating rooms. The incidence of contamination and the factors that may increase the concentrations of ambient anesthetic gases have not been evaluated fully during routine circumstances, however. METHODS: Concentrations of nitrous oxide (N2O) in ambient air were monitored automatically in 10 operating rooms in Kagoshima University Hospital from January to March 1997. Ambient air was sampled automatically from each operating room, and the concentrations of N2O were analyzed every 22 min by an infrared spectrophotometer. The output of the N2O analyzer was integrated electronically regarding time, and data were displayed on a monitor in the administrative office for anesthesia supervisors. A concentration of N2O > 50 parts per million was regarded as abnormally high and was displayed with an alarm signal. The cause of the high concentration of N2O was then sought. RESULTS: During the 3-month investigation, N2O was used in 402 cases. Abnormally high concentrations of N2O were detected at some time during 104 (25.9%) of those cases. The causes were mask ventilation (42 cases, 40.4% of detected cases), unconnected scavenging systems (20 cases, 19.2%), leak around uncuffed pediatric endotracheal tube (13 cases, 12.5%), equipment leakage (12 cases, 11.5%), and others (17 cases, 16.4%). CONCLUSIONS: N2O contamination was common during routine circumstances in our operating rooms. An unconnected scavenging system led to the highest concentrations of N2O recorded. Proper use of scavenging systems is necessary if contamination by anesthetic gas is to be limited.  相似文献   
80.
Overexpression of HER2 protein and HER2 gene amplification in breast cancer are prognostic factors for the response to specific medical treatments such as trastuzumab, endocrine therapy, and chemotherapy. Whereas HER2 expression and gene amplification are generally examined in tissue sections, we investigated whether specimens from fine needle aspiration cytology (FNAC) are adequate for these analyses. HER2 protein overexpression and HER2 gene amplification were assessed in both FNAC specimens and tissue sections from 58 cases of invasive breast cancer. Immunohistochemistry assay for HER2 protein expression was performed according to the HercepTest protocol, and HER2 gene amplification was examined with the Spot-light CISH (chromogenic in situ hybridization) Detection kit. There was a significant positive correlation between assessments of HER2 protein status in the cytology specimens and tissue sections. The sensitivity, specificity, and accuracy of HER2 gene amplification detection in cytology specimens in relation to those in tissue sections were 84.0% (21/25 cases), 87.9% (29/33 cases), and 86.2% (50/58 cases), respectively. FNAC specimens are suitable for detection of HER2 overexpression and HER2 gene amplification in invasive breast cancer.  相似文献   
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