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571.
Twenty-eight percent of 13-month-old male mice of the high antibody responder line of Biozzi's selection I (HI) spontaneously developed a long-lasting inflammatory arthritis. This disease was clinically and histologically similar to human rheumatoid arthritis. The synovium of joints and some tendons was hypertrophied, with thickening of the synovial cell layer and infiltration by polymorphonuclear and mononuclear leukocytes. In some cases, synovial pannus formation led to destructive damage of articular cartilage and bone. Rheumatoid factor and antinuclear, anti-DNA, and anti-type II collagen (CII) antibodies were often found in the sera of both arthritic mice and clinically normal littermates. The presence of CII autoantibodies in this line of mice suggests that a potentially harmful anti-CII T cell autoimmunity can also develop spontaneously and lead to joint damage. Moreover, HI mice are also susceptible to collagen-induced arthritis, while a closely related mouse line (HII) is resistant to both diseases. These data support the hypothesis that collagen-induced arthritis is pathogenetically related both to this spontaneous arthritis and to rheumatoid arthritis.  相似文献   
572.
We have imaged, in real time, fluorescent tumors growing and metastasizing in live mice. The whole-body optical imaging system is external and noninvasive. It affords unprecedented continuous visual monitoring of malignant growth and spread within intact animals. We have established new human and rodent tumors that stably express very high levels of the Aequorea victoria green fluorescent protein (GFP) and transplanted these to appropriate animals. B16F0-GFP mouse melanoma cells were injected into the tail vein or portal vein of 6-week-old C57BL/6 and nude mice. Whole-body optical images showed metastatic lesions in the brain, liver, and bone of B16F0-GFP that were used for real time, quantitative measurement of tumor growth in each of these organs. The AC3488-GFP human colon cancer was surgically implanted orthotopically into nude mice. Whole-body optical images showed, in real time, growth of the primary colon tumor and its metastatic lesions in the liver and skeleton. Imaging was with either a trans-illuminated epifluorescence microscope or a fluorescence light box and thermoelectrically cooled color charge-coupled device camera. The depth to which metastasis and micrometastasis could be imaged depended on their size. A 60-microm diameter tumor was detectable at a depth of 0.5 mm whereas a 1, 800-microm tumor could be visualized at 2.2-mm depth. The simple, noninvasive, and highly selective imaging of growing tumors, made possible by strong GFP fluorescence, enables the detailed imaging of tumor growth and metastasis formation. This should facilitate studies of modulators of cancer growth including inhibition by potential chemotherapeutic agents.  相似文献   
573.
574.

Purpose

Extent of lung contusion on initial computed tomography (CT) scan predicts the occurrence of acute respiratory distress syndrome (ARDS) in blunt chest trauma patients. We hypothesized that lung ultrasonography (LUS) on admission could also predict subsequent ARDS.

Methods

Forty-five blunt trauma patients were prospectively studied. Clinical examination, chest radiography, and LUS were performed on arrival at the emergency room. Lung contusion extent was quantified using a LUS score and compared to CT scan measurements. The ability of the LUS score to predict ARDS was tested using the area under the receiver operating characteristic curve (AUC-ROC). The diagnostic accuracy of LUS was compared to that of combined clinical examination and chest radiography for pneumothorax, lung contusion, and hemothorax, with thoracic CT scan as reference.

Results

Lung contusion extent assessed by LUS on admission was predictive of the occurrence of ARDS within 72 h (AUC-ROC = 0.78 [95 % CI 0.64–0.92]). The extent of lung contusion on LUS correlated well with CT scan measurements (Spearman’s coefficient = 0.82). A LUS score of 6 out of 16 was the best threshold to predict ARDS, with a 58 % [95 % CI 36–77] sensitivity and a 96 % [95 % CI 76–100] specificity. The diagnostic accuracy of LUS was higher than that of combined clinical examination and chest radiography: (AUC-ROC) 0.81 [95 % CI 0.50–1.00] vs. 0.74 [0.48–1.00] (p = 0.24) for pneumothorax, 0.88 [0.76–1.00] vs. 0.69 [0.47–0.92] (p < 0.05) for lung contusion, and 0.84 [0.59–1.00] vs. 0.73 [0.51–0.94] (p < 0.05) for hemothorax.

Conclusions

LUS on admission identifies patients at risk of developing ARDS after blunt trauma. In addition, LUS allows rapid and accurate diagnosis of common traumatic thoracic injuries.  相似文献   
575.
576.
Six different antibiotic treatment regimens were compared for efficacy in rabbits with endocarditis induced by inoculation with a nutritionally variant strain of streptococcus. Seven untreated animals, sacrificed at day 11, had vegetations containing 8.89 +/- 1.35 log10 CFU/g, none of which was sterile. The vegetations from the rabbits in all treated groups had bacterial titers significantly lower than those of the controls (P less than 0.001). Vegetations from penicillin-treated animals averaged 5.14 +/- 1.00 log CFU/g, and no vegetations were sterile. Treatment with penicillin plus gentamicin or amikacin was more effective than treatment with penicillin alone, resulting in 3.99 +/- 0.94 log CFU/g of vegetation and sterile lesions in 5 of 12 animals. Treatment with vancomycin alone was as least as efficient as that with penicillin plus an aminoglycoside, resulting in an average of 3.33 +/- 0.96 log CFU/g of vegetation and sterile lesions in five of eight animals. Treatment with vancomycin plus an aminoglycoside was not superior to treatment with vancomycin alone, resulting in an average of 3.68 +/- 1.37 log CFU/g of vegetation and sterile lesions in 8 of 13 animals. These in vivo results correlated poorly with the in vitro susceptibility of the strain to the various antibiotics, as measured by the time-kill method. These results support the current practice of using vancomycin as alternative therapy when a penicillin-aminoglycoside combination is ineffective or contraindicated in patients with endocarditis caused by nutritionally variant streptococci.  相似文献   
577.
Domestic animals have played a key role in human history. Despite their importance, however, the origins of most domestic species remain poorly understood. We assessed the phylogenetic history and population structure of domestic goats by sequencing a hypervariable segment (481 bp) of the mtDNA control region from 406 goats representing 88 breeds distributed across the Old World. Phylogeographic analysis revealed three highly divergent goat lineages (estimated divergence >200,000 years ago), with one lineage occurring only in eastern and southern Asia. A remarkably similar pattern exists in cattle, sheep, and pigs. These results, combined with recent archaeological findings, suggest that goats and other farm animals have multiple maternal origins with a possible center of origin in Asia, as well as in the Fertile Crescent. The pattern of goat mtDNA diversity suggests that all three lineages have undergone population expansions, but that the expansion was relatively recent for two of the lineages (including the Asian lineage). Goat populations are surprisingly less genetically structured than cattle populations. In goats only approximately 10% of the mtDNA variation is partitioned among continents. In cattle the amount is >/=50%. This weak structuring suggests extensive intercontinental transportation of goats and has intriguing implications about the importance of goats in historical human migrations and commerce.  相似文献   
578.
Background: We have shown in FG pancreatic cancer cells that α2β1 integrin-mediated type I collagen adhesion decreases parathyroid hormone-related protein (PTHrP), inerleukin-6 (IL-6), and interleukin-8 (IL-8) expression, decreases the localization of E-cadherin and β-catenin in cell-cell contacts, increases cell migration, and increases glycogen synthase kinase 3 (GSK3) and protein kinase B (PKB/Akt) phosphorylation states relative to α5β1 integrin-mediated fibronectin (Fn) adhesion. Aim of the Study: To extend our observations in FG cells to other pancreatic cancer cell lines, and to determine whether E-cadherin-mediated cell-cell adhesion and its downstream effectors were functionally involved in the ECM-mediated regulation of PTHrP, IL-6, and IL-8. Methods: We used standard biochemical techniques to determine ECM-specific differences in E-cadherin and β-catenin localization, GSK3 and PKB/Akt phosphorylation, haptokinetic cell migration, and cytokine expression in pancreatic cancer cells. We also conducted functional studies using pharmacological inhibitors for GSK3 and PKB/Akt, as well as elevated Mg2+/Ca2+ ratios similar to pancreatic juice, and examined their effects on cytokine expression. Results: Differences in E-cadherin and β-catenin localization along with GSK3 and PKB/Akt phosphorylation occur in multiple pancreatic cancer cell lines, resulting in differences in ECM-mediated haptokinesis and cytokine expression that are generally consistent with previous observations in FG cells. Our functional studies also suggest that E-cadherin-mediated cell-cell adhesion and downstream effectors are involved in PTHrP, IL-6, and IL-8 expression. Conclusions: These data indicate that α2β1 integrin-mediated type I collagen adhesion disrupts cell-cell adhesion architecture, resulting in increased migration and decreased PTHrP, IL-6, and IL-8 expression in pancreatic cancer cells.  相似文献   
579.
This dose–response study aimed to determine the dose of remifentanil combined with propofol 2.5 mg.kg−1 which provided excellent intubation conditions in 95% of patients. Ninety premedicated female ASA 1 and 2 patients were randomly allocated to five remifentanil dose groups (1, 2, 3, 4 or 5 μg.kg−1). Induction of anaesthesia was performed with a blinded dose of remifentanil infused over 60 s simultaneously co-administered with propofol 2.5 mg.kg−1 infused over 45 s. Tracheal intubation was attempted 150 s after the beginning of induction. Intubating conditions were assessed with the Copenhagen score. A probit analysis was performed to calculate the intubating efficient doses (IED) of remifentanil in 95% of patients (IED95). Our data revealed that the IED95 of remifentanil was 4.0 (95% CI: 3.4–5.6) μg.kg−1, which was associated with a maximum decrease in heart rate and mean arterial pressure of < 30%, a finding which also applied to the other groups.  相似文献   
580.
The comparison of cancer cell seeding, deformation and viability in the lung, muscle and liver of nude mice in real-time is reported here. The mice were intubated to support ventilation with positive end-respiratory pressure (PEEP) for imaging on the lung. Human fibrosarcoma cells with green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm (dual-color HT-1080 cells) were injected into the tail vein for lung imaging, the portal vein for liver imaging or the abdominal aorta for muscle imaging which was performed with an Olympus OV100 Small Animal Imaging System. The length of the cytoplasm and nuclei in 20 seeded cancer cells were measured. A large number of cells initially arrested in the lung capillaries and many cells formed aggregates. The cell number decreased rapidly at 6 and 24 h. There was no significant difference in cancer cell survival when immunocompetent C57BL/6 mice were used in place of the nude mice, suggesting that T cell reaction is not very important in the first 24 h after seeding of cancer cells in the lung. In the lung and liver, little cancer cell deformation occurred. In contrast in the muscle, the cytoplasm and nuclei of the seeded cells were highly deformed and many fragmented cells were observed. The rate of cancer cell death was highest in the lung and lowest in the muscle. In each organ, single disseminated cells tended to die earlier than aggregated cells. The results of this study suggest that the early steps of metastasis are different in the lung, liver and muscle.  相似文献   
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