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31.
Eighteen patients with invasive periadventitial tissue (T4)or distant lymph node metastatic (M1,LYM) squamous cell carcinomawere entered into a pilot study of neoadjuvant chemotherapywith etoposide (50 mg/m2/day, days 1–5), leucovorin (30mg/body/day, days 2–5), 5-fluorouracil (5-FU; 400 mg/m2/day,days 2–5) and cisplatin (100 mg/m2–day, day 1) (ELFP).The overall response rate was 56%. The response rates in theT4 tumor and M1, LYM patients were 56 and 50%, respectively.Radical esophagectomies were performed on six of 17 patientswho had completely recovered from the chemotherapy, a resectabilityof 35%. Histologically, the primary tumor was moderately toslightly effective, and the lymph nodes markedly to moderatelyeffective. Histologic responses in the lymph nodes were differentfrom those in the primary tumors and in each node. There werefour chemo-surgically related deaths. Median survival timesin responding and non-responding patients were nine and threemonths, respectively. In conclusion, neoadjuvant chemotherapywith ELFP appears to be effective against esophageal squamouscell cancer with periadventitial tissue invasion or distantlymph node metastasis. Chemo-surgically related deaths werehowever, 22%, showing neoadjuvant chemotherapy to necessitateextremely careful attention to the medical and surgical managementof patients.  相似文献   
32.
Exogenous lipoid pneumonia following ingestion of liquid paraffin   总被引:1,自引:0,他引:1  
An asymptomatic patient with exogenous lipoid pneumonia (ELP) due to silent aspiration of liquid paraffin ingested as a lubricant was diagnosed by bronchoalveolar lavage (BAL). BAL fluid separated into oily upper phase and lower aqueous phase spontaneously. Microscopic analysis of BAL cells revealed the presence of lipid-laden alveolar macrophages. Classic histochemical staining and electron microscope examination indicated that neutral lipid was dominant but phospholipid was also present in the lipid-laden macrophages. Together with the history of ingestion of liquid paraffin, we identified that the ingested liquid paraffin was the origin of the neutral lipid in the lipid-laden macrophages observed in the BAL fluid.  相似文献   
33.
AIMS: To investigate the correlation between in vitro permeation of 11 beta-lactam antibiotics across rat jejunum and their oral bioavailability in humans. METHODS: The absorptive and secretory permeation across rat jejunum was evaluated and apparent permeability coefficients (P(app)) were determined. RESULTS: A steep, sigmoid-type curve was obtained for the relationship between P(app) in the absorptive permeation and human oral bioavailability. When the ratios of P(app) in the absorptive direction to P(app) in the secretory direction were plotted against human oral bioavailability, a much improved correlation was obtained (r = 0.98, P < 0.001). The addition of glycylglycine to both mucosal and serosal media modified the permeation of ceftibuten and cephalexin from the absorptive to the secretory direction. CONCLUSIONS: For 11 beta-lactam antibiotics rat intestinal permeation correlated well with human oral bioavailability, especially when corrected for secretory transport.  相似文献   
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BACKGROUND: The activation of p38 mitogen-activated protein kinase (MAPK) plays an important role in the development of ischemia/reperfusion injury. FR167653 is a novel p38 MAPK inhibitor. This study evaluated the effects of p38 MAPK inhibition during cold ischemia on subsequent reperfusion injury using FR167653 as an additive to Euro-Collins solution in canine lung transplantation. METHODS: Canine orthotopic left lung transplantation was performed after 12-hr cold storage using Euro-Collins solution, with or without FR167653. Fifteen minutes after reperfusion, the right pulmonary artery and the right stem bronchus were ligated, and the animals were observed for 4 hr after reperfusion. Left pulmonary vascular resistance (L-PVR), cardiac output (CO), arterial oxygen pressure (Pao2), and alveolar-arterial oxygen pressure difference (A-aDo2) were measured. Lung specimens were harvested for wet-to-dry lung weight ratio (WDR) measurements, histopathologic studies, and polymorphonuclear neutrophil (PMN) counts. The activities of p38 MAPK in lung grafts were evaluated. RESULTS: The addition of FR167653 significantly (P<0.05) improved Pao2, A-aDo2, L-PVR, CO, and WDR and suppressed PMN infiltration after transplantation. FR167653 also ameliorated histologic damage to the lung graft. During cold storage, p38 MAPK was not activated in the lung graft, whereas it was markedly activated 30 min after reperfusion. FR167653 significantly (P<0.05) inhibited p38 MAPK activation 30 min after reperfusion. CONCLUSIONS: The addition of FR167653 to Euro-Collins solution improved lung graft viability associated with the inhibition of p38 MAPK activation. These results suggest that inhibiting p38 MAPK activation may attenuate ischemia/reperfusion injury in lung transplantation.  相似文献   
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37.
BACKGROUND: Normal bronchial epithelium gradually acquires cellular and genetic changes that result in the formation of invasive tumors. The objective of this study was to evaluate the degree of proliferative change and the amount of neovascularization in both normal and preneoplastic lesions in smokers who were at high risk for developing lung carcinoma. METHODS: The authors studied bronchial biopsy specimens from 7 nonsmokers and 52 smokers. Immunohistochemical staining of the specimens with antibodies for the presence of p53 protein, Ki-67 and CD34 antigens, and vascular endothelial growth factor was performed. The proliferation index (PI) was assessed by immunohistochemical staining for Ki-67 antigen. RESULTS: Overexpression of p53 protein was observed frequently in regions of squamous dysplasia and in squamous cell carcinoma tissue. The PI of normal epithelium from smokers was increased compared with nonsmokers, and the difference was statistically significant (P < 0.05). The microvessel count (MC) in normal mucosa obtained from smokers was higher compared with the MC in normal mucosa obtained from nonsmokers (P < 0.05). A significant difference in MC also was observed between regions of squamous metaplasia or dysplasia with projections of capillary loops into the bronchial mucosa and similar lesions without capillary loops (P < 0.005); however, there was no difference in either the PI or the incidence of p53 overexpression between these groups. CONCLUSIONS: These results show that smoking appears to induce both a proliferative response and neovascularization in bronchial mucosa. The projection of capillary loops into the bronchial mucosa also may be a result of neovascularization occurring within the lamina propria of the bronchial wall.  相似文献   
38.
Adenosine triphosphate (ATP) has been shown to be an inhibitory or a stimulatory agent for cell growth in various types of cells. Here, we studied the effects of extracellular ATP on two pancreatic cancer cell lines, PK-1 and YAPC established by us. In both cell lines, ATP inhibited cell growth in a time- and dose-dependent manner, whereas the same doses of ATP stimulated DNA synthesis. Flow cytometric analysis of the cells incubated with or without ATP demonstrated the ATP-induced striking increase in cells at S-phase. The same analysis showed also the increase in sub-G0/G1 population in the same analysis and the electrophoretic pattern of DNA showed the occurrence of ATP-induced cell disintegration likely to be apoptosis. We suggest that extracellular ATP is cytotoxic for pancreatic cancer cells because of its induction of cell cycle arrest at S-phase and cell death, possibly apoptosis, overcoming the promotion of the entry into S-phase.  相似文献   
39.
CASE REPORT: A suicide attempt by a 23-year-old woman involved ingestion of 1000 mL of petroleum naphtha. Early chemical pneumonitis was complicated by life-threatening, diffuse interstitial lung consolidation with pneumatoceles. Pulse steroid therapy beginning on day 17 was associated with remarkable resolution of interstitial consolidation, although an enlarging secondarily infected pneumatocele ruptured to produce a bronchopleural fistula. Thoracic surgery and antibiotic therapy resulted in improvement of the patient's respiratory condition, and she was discharged with no residual respiratory symptoms. High-dose corticosteroid therapy appears to be a useful addition to aggressive supportive treatment in late adult respiratory distress syndrome following hydrocarbon ingestion.  相似文献   
40.
One hundred and seventy patients received breast-conserving therapy in the Second Department of Surgery, Gunma University School of Medicine. Six (3.5%) out of the 170 patients showed breast recurrence. We investigated the breast recurrent cases clinicopathologically. The age at the initial operation ranged from 38 to 78 (mean 57) years. One patient was clinical stage I and the others were clinical stage II. Surgical margin at the initial operation was negative in two patients and positive in four. Histological type was invasive ductal cancer in all cases. Three patients had lymph node involvement. The interval from the initial operation to breast recurrence ranged from 19 to 68 months. Five cases were nodular type and one was diffuse type of breast recurrence. Histological type of breast recurrence was the same as the initial one. We performed salvage surgery for all breast recurrent patients, mastectomy for four patients and local resection for two. One patient who showed diffuse type of recurrence could not be controlled with any surgical treatment, and later died of breast cancer. We investigated the expression of estrogen receptor, progesterone receptor, pS2, c-erbB-2 and p53 on both initial and recurrent specimens of the six patients. The expression of each protein on the recurrent specimens was the same as the initial one. We conclude that breast recurrence after breast-conserving therapy has its origin in the residue of cancer cells at the initial operation, even if surgical margins are histopathologically negative.  相似文献   
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