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941.
STUDY OBJECTIVE: Respiratory disturbance caused by ARDS has been reported during administration of granulocyte-colony stimulating factor. The clinical features of such respiratory distress were investigated in this study. DESIGN: Retrospective case review. SETTING: A 1,100-bed university teaching hospital. PATIENTS: Five patients who had dyspnea caused by ARDS develop after chemotherapy or bone marrow transplantation (BMT) at our hospital. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Levels of cytokines, human leukocyte antigen (HLA) typing, and the clinical course were analyzed to clarify common features. All five patients possessed HLA-B51 or HLA-B52, and all had fever and an enhanced inflammatory response at the time of the WBC nadir. The tumor necrosis factor (TNF)-alpha and interleukin (IL)-8 levels increased when respiratory distress syndrome occurred. CONCLUSIONS: If patients with HLA-B51 or HLA-B52 have infection develop at the time of WBC nadir after chemotherapy or BMT, ARDS may occur in association with elevation of TNF-alpha and IL-8 during WBC recovery.  相似文献   
942.
In the XX/XY sex-determining system, the Y-linked SRY genes of most mammals and the DMY/Dmrt1bY genes of the teleost fish medaka have been characterized as sex-determining genes that trigger formation of the testis. However, the molecular mechanism of the ZZ/ZW-type system in vertebrates, including the clawed frog Xenopus laevis, is unknown. Here, we isolated an X. laevis female genome-specific DM-domain gene, DM-W, and obtained molecular evidence of a W-chromosome in this species. The DNA-binding domain of DM-W showed a strikingly high identity (89%) with that of DMRT1, but it had no significant sequence similarity with the transactivation domain of DMRT1. In nonmammalian vertebrates, DMRT1 expression is connected to testis formation. We found DMRT1 or DM-W to be expressed exclusively in the primordial gonads of both ZZ and ZW or ZW tadpoles, respectively. Although DMRT1 showed continued expression after sex determination, DM-W was expressed transiently during sex determination. Interestingly, DM-W mRNA was more abundant than DMRT1 mRNA in the primordial gonads of ZW tadpoles early in sex determination. To assess the role of DM-W, we produced transgenic tadpoles carrying a DM-W expression vector driven by approximately 3 kb of the 5'-flanking sequence of DM-W or by the cytomegalovirus promoter. Importantly, some developing gonads of ZZ transgenic tadpoles showed ovarian cavities and primary oocytes with both drivers, suggesting that DM-W is crucial for primary ovary formation. Taken together, these results suggest that DM-W is a likely sex (ovary)-determining gene in X. laevis.  相似文献   
943.
BACKGROUND: An imaging modality that can be used to identity small stones after a biliary lithotripsy is required. Intraductal ultrasonography was evaluated by using percutaneous transhepatic cholangioscopy as the gold standard. METHODS: Lithotripsy, under percutaneous transhepatic cholangioscopy guidance, was performed in 20 patients. A thin-caliber ultrasonic probe (2.0 mm in diameter and 20 MHz frequency) was inserted into the bile duct through the percutaneous tract after lithotripsy, and residual stones were identified. This was followed by percutaneous transhepatic cholangioscopy. RESULTS: In the extrahepatic bile ducts, intraductal ultrasonography provided images of all the stones demonstrated on cholangioscopy (n = 11). The sensitivity was superior to that of cholangiography (P < 0.005). However, in the intrahepatic bile ducts, intraductal ultrasonography only visualized the stones located in the cannulated lobe. Extrahepatic stones smaller than 5.0 mm in diameter or in a common hepatic duct larger than 15.0 mm in diameter were missed by cholangiography, but were visualized by the use of intraductal ultrasonography (P < 0.05). CONCLUSIONS: Intraductal ultrasonography is equivalent to cholangioscopy in the extrahepatic bile ducts. Cholangiography and intraductal ultrasonography should be used in combination to image intrahepatic and extrahepatic stones.  相似文献   
944.
BACKGROUND: The utility of intraductal US via the transpapillary route prior to biliary drainage in the assessment of longitudinal extension of extrahepatic bile duct carcinoma was investigated. METHODS: In 19 patients with extrahepatic bile duct carcinoma who underwent surgical resection, an ultrasonic probe (diameter, 2.0 mm; frequency, 20 MHz) was inserted into the bile duct via the transpapillary route prior to biliary drainage. Longitudinal cancer extension along the bile duct was prospectively determined and compared with the histologic findings in the resected specimens. RESULTS: Results on the hepatic side were as follows: Intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 9 of 19 patients with one instance of overdiagnosis. The accuracy of intraductal US in assessing the extent of spread (84%) was superior to that of cholangiography (47%) (p < 0.05). Results on the duodenal side were as follows: In patients with suprapancreatic bile duct cancer (n = 14), intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 8 of 14 patients. The accuracy of intraductal US in assessing the extent of the spread (86%) was superior to that of cholangiography (43%) (p < 0.05). CONCLUSIONS: Transpapillary intraductal US prior to biliary drainage is useful in demonstrating longitudinal extension of bile duct cancer. However, the surgical margins were inaccurate in some patients.  相似文献   
945.
A 42-year-old man had swelling in the right side of the neck, cough and chest pain. On admission, an abnormal shadow was detected in the right upper lung field and squamous cell carcinoma of the lung with superior vena cava (SVC) syndrome was diagnosed. Concurrent radiotherapy and systemic chemotherapy consisting of cisplatin and vinorelbine induced a partial response. At 15 months after diagnosis, he was re-admitted because of bilateral pleural effusion and facial edema due to relapse of SVC syndrome. Examination of the milky right pleural effusion revealed chylothorax (959mg/dl of beta-lipoprotein and 675mg/dl of triglyceride). The right effusion was finally controlled by pleurodesis with OK-432. Non-traumatic chylothorax is a rare complication of lung cancer.  相似文献   
946.
Some mouse myeloid leukemias induced by X-irradiation and serially transplanted into syngenic mice do not proliferate in vitro even in the presence of hematopoietic factors. To examine whether such leukemic cells can proliferate in response to stromal cells, we cocultured them with MC3T3-G2/PA6 (PA6) preadipocytes, cells that can support the growth of hematopoietic stem cells. All leukemias developed into in vitro cell lines, showing a dependence on contact with the PA6 cells. Two cell lines responded to none of the known hematopoietic factors including interleukin-3 (IL-3), IL-4, IL-5, IL-6, GM-CSF, G-CSF, M-CSF, and Epo. These results demonstrate that the mechanism of the action of PA6 cells is different from that of any of the known hematopoietic factors, and that, because these two leukemic cell lines retained the ability to grow in vivo, responsiveness to the known hematopoietic factors is not essential for the leukemic cell growth in vivo. Furthermore, all leukemic cell lines could respond also to the preadipocytes fixed with formalin, paraformaldehyde, or glutaraldehyde, suggesting that some molecule(s) associated with the surface of PA6 cells or with extracellular matrix secreted by the preadipocytes is responsible for the leukemic cell growth.  相似文献   
947.
On routine physical checkup, a 27-year-old man with productive cough was found to have multiple nodules with cavitation in the bilateral lung fields and mediastinal and hilar lymph adenopathy on chest X-ray film and CT scan. Serum levels of angiotensin converting enzyme and lysozyme were high. Tuberculin reaction was negative. Non-caseous epitheloid granulomas were confirmed in the bronchial wall specimens obtained by trans-bronchial biopsy. The number of lymphocytes and the CD4/CD8 ratio of lymphocytes in bronchoalveolar lavage fluid was increased. Therefore, pulmonary sarcoidosis was diagnosed, and the lung nodules with cavitation were considered due to sarcoidosis. The walls of the cavitations gradually thinned and had almost completely vanished after 6 months of careful observation without steroid therapy.  相似文献   
948.
Previously, we reported a case of localized plasma cell type Castleman's disease with severe hepatomegaly and reactive systemic AA amyloidosis. The amyloid deposits were demonstrated in both the hepatic tissue and in the gastric mucosa. Surgical resection of an isolated extra-hepatic tumor was performed. The laboratory findings, including SAA and IL-6, remained within normal limits and the patient's hepatomegaly subsequently showed regression. Nine years after the operation, no amyloid deposition was seen in the gastric mucosa and the patient's liver was of normal size. Our findings with long-term follow up in this case indicated that the cessation of SAA production was the probable cause of histopathological regression of AA amyloid deposits in this patient.  相似文献   
949.
950.
The authors investigated the effect of diesel exhaust (DE) on cytokine expression in murine lung tissues. BALB/c mice were exposed to DE for 1 month at different dose levels of DE (low dose: diesel exhaust particles [DEP] 100 micro g/m(3); high dose: 3mg/m(3)). After exposure, the authors examined mRNA expression of cytokines (tumor nocrosis factor alpha [TFN-alpha], Interleukin [IL]-1beta, IL-4, IL-6, IL-10, IL-12p40, and interferon gamma [IFN-gamma] and inducible nitric oxide synthase (iNOS) in the lung, and also measured the secretion of TNF-alpha and IL-10 protein by alveolar macrophages (AM). The mRNA expression levels of inflammatory cytokines (TNF-alpha, IL-1beta, IL-6, IL-12p40, IFN-gamma) and iNOS, which are important for host defense, were suppressed significantly. However, the IL-10 mRNA level was increased by DE exposure. The IL-4 mRNA level was increased by low-dose DE exposure but suppressed by high-dose DE exposure. TNF-alpha and IL-10 secretion by AM paralleled mRNA expression. Chronic inhalation of DE affects cytokine expression in murine lung. These results suggest that DE alters immunological responses in the lung and may increase susceptibility to pathogens, and that increased IL-4 expression by low-dose DE exposure may induce allergic reaction such as asthma.  相似文献   
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