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61.
Carbachol (CCh) enlarges the luminal space in rat parotid intralobular ducts, but the mechanism of their enlargement remains obscure. We investigated the involvement of intracellular calcium ions in the enlargement of luminal space by monitoring the luminal space under optical sectioning in a confocal laser scanning microscope using sulforhodamine B. Carbachol increased the intracellular concentration of calcium ions ([Ca2+]i) and the inside diameter without any change in the outside diameter. Removal of extracellular calcium ions modulated CCh-induced changes in [Ca2+]i to transient, but did not markedly inhibit the CCh-induced increase in the inside diameter. Additional loading of BAPTA (1,2-bis (o-aminophenoxy-ethane-n,n,n',n'-tetraacetic acid) in the duct cells suppressed CCh-induced changes. Diphenylamine-2-carboxylate (DPC), but not cytochalasin D, calmodulin inhibitor or nitric oxide synthase inhibitor profoundly suppressed CCh-induced changes. These results suggest that CCh induces enlargement of the luminal space through the activation of DPC-sensitive channels by the release of calcium ions from the intracellular pool.  相似文献   
62.
BACKGROUND: Acute lung injury is a frequent extraabdominal complication of bacterial peritonitis, and neutrophil plays an important role in this lung damage. Macrophage inflammatory protein 2 (MIP-2) serves the same chemotactic function as IL-8 which is a potent neutrophil chemotactic factor in humans, and we investigated the role of MIP-2 associated with neutrophil recruitment in the lung of murine peritonitis. METHODS: Cecal ligation and puncture (CLP) were performed on mice. MIP-2 levels in blood and lung tissue, MIP-2 mRNA expression in lung tissue and bronchoalveolar lavage fluid (BALF), and CD11b expression on peripheral blood neutrophil and BALF cells were determined after CLP. In addition, we investigated the effect of anti-MIP-2 antibody on the lung injury associated with peritonitis. RESULTS: MIP-2 mRNA expression was observed in lung tissue after CLP and numerous neutrophils were accumulated in the lung under those conditions. Anti-MIP-2 antibody contributed to the inhibition of the CD11b expression and chemotaxis of pulmonary neutrophils, lung edema, and thus the reduction in peritonitis-related mortality. CONCLUSIONS: MIP-2 plays a pivotal role in neutrophil recruitment in the lung following peritonitis, and control of neutrophil accumulation in the lung by neutralizing MIP-2 is recommended as a new therapeutic approach to the lung damage associated with peritonitis.  相似文献   
63.
We demonstrated previously (S. Kawamura et al., Int. J. Cancer, 94: 343-347, 2001) that large amounts of ganglioside G(M3) accumulate in superficial bladder tumor, compared with invasive bladder tumors and that exogenous G(M3) inhibits the invasive potential of bladder tumor cells. To apply the G(M3) overexpression system to bladder tumor therapy, direct evidence for the important role of G(M3) in bladder tumor invasion must be obtained through transfer of the gene responsible for G(M3) overexpression. To determine the most appropriate cancer cell line for elucidating the antitumor effect of ganglioside G(M3) overexpression, the present study examined glycolipid composition, enzyme activity, and mRNA expression of the glycosyltransferases responsible for G(M3) synthesis in the bladder tumor cell lines KK-47, J82, MGH-UI, YTS-1, and MBT-2. A murine bladder carcinoma cell line (MBT-2) was transfected with a G(M3) synthase [(lactosylceramide alpha2,3-N-acetyl sialic acid transferase); sialyltransferase-I; SAT-I] cDNA, because this line does not naturally express G(M3). Stable transfectants (MBT-2-SAT-I) that overexpressed G(M3) were characterized by a reduced potential for cell proliferation, motility, invasion, and xenograft tumor growth, and an increase in the number of apoptotic cells. In the proportion of synthetic S phase, cells did not differ between MBT-2-SAT-I and mock-transfectant cells. These results suggest that the decreased proliferative potential related to G(M3) overexpression was attributable to the increased number of apoptotic cells. Although details of the mechanism of apoptosis remain unclear, the overexpression of G(M3) by gene transfer of SAT-I may present a novel therapeutic modality.  相似文献   
64.
Endothelial carbohydrate binding proteins, E- and P-selectins, are thought to mediate sialyl Lewis A/X-dependent hematogenous cancer metastasis. We tested this hypothesis using sialyl Lewis X-dependent B16 melanoma lung targeting and its inhibition with selectin ligand mimicry peptide, IELLQAR. In E/P-selectin doubly deficient mutant mice, sialyl Lewis X-expressing B16 melanoma cells colonized the lung, and IELLQAR inhibited this colonization. However, tumors grown in E/P-selectin-deficient mice were significantly smaller than those grown in wild-type mice. These results indicate that the IELLQAR peptide receptor expressed in the lung vasculature plays a major role in sialyl Lewis X-dependent cancer cells targeting to the lung.  相似文献   
65.
OBJECTIVES: Biochemical modulation (BM) was initially used to enhance the effect of 5-fluorouracil (5-FU) by modulating its pharmacological action with the addition of other drugs. BM with low-dose cisplatin and 5-FU or UFT has been examined in cases of advanced gastric or pancreas cancer and 30 to 40% response rates have been reported. In the present study, the effect of BM on hormone refractory prostate cancer (HRPC) patients was examined. METHODS: BM consisting of 5 mg/body of cisplatin 3 times per week and 300-450 mg of UFT/day was given to 30 HRPC patients (median and range of age: 66 and 52-72, respectively). The ECOG performance status was 0 to 1. Gleason score was 7 in 8 patients, 8 in 10 patients and 9 in 12 patients, respectively. The metastatic site was bone in 29 patients (extent of disease on bone scan [EOD] grade 1: 10, 2: 10, 3: 8, 4: 1), lymph node in 8 and liver in 1. RESULTS: Among the 29 patients assessable for bone metastasis, 5 (17%) obtained marked improvement on bone scan. One was EOD grade 4 (super bone scan) and 4 were EOD grade 1-3. Eight (28%) were stable and 16 (55%) progressed on bone scan. Among 8 patients with lymph node metastasis, 4 (50%) showed partial response and 4 (50%) progression. One patient with liver metastasis showed complete response. Fourteen (47%) out of 30 patients showed a PSA decline of 50% or greater. Their median response duration was 8 months (range; 2 to 44 months). Among the 25 patients assessable for bone pain, 7 (28%) improved, 12 (48%) remained stable and 6 (24%) progressed. A side effect of Grade II anemia was seen in one patient. CONCLUSION: BM is effective in almost half of hormone refractory prostate cancer patients.  相似文献   
66.
We investigated the effectiveness of continuous hyperthermic peritoneal perfusion (CHPP) for the peritoneal dissemination of gastric cancer. A total 124 patients with advanced gastric cancer were enrolled in this study. Prophylactic CHPP (P-CHPP) was performed in 45 patients who had macroscopic serosal invasion without peritoneal dissemination, and 79 patients without CHPP were a control group. Therapeutic CHPP (T-CHPP) was performed in 21 patients with peritoneal dissemination, and 52 patients without CHPP were a control group. There was no significant difference in 5 year survival between patients treated and not treated with P-CHPP. Univariate analysis showed that location of tumor, tumor diameter, and lymph node metastasis influenced prognosis, but there was no prognostic factor in the Cox proportional regression hazard model. There was no significant difference in 5-year survival between patients treated and not treated with T-CHPP. Univariate analysis showed that degree of peritoneal dissemination and adjuvant chemotherapy influenced prognosis, and the Cox proportional regression hazard model showed that the macroscopic types and degree of peritoneal dissemination affected prognosis. In the patients with CHPP, the incidences of respiratory failure and renal failure were each statistically greater than in the patients undergoing CHPP.  相似文献   
67.
We report a 75-year-old woman with chronic obstructive pulmonary disease (COPD) suffering from cough, sputum, high-grade fever and dyspnea on effort. Her chest radiograph revealed an infiltrative shadow in the right lower lung field and her laboratory data showed marked inflammatory changes. Her arterial blood gas analysis showed marked hypoxemia and hypercapnia. After her laboratory data and general condition improved, we performed pulmonary rehabilitation for the patient for about 6 weeks. The program consisted of pursed lip breathing, diaphragmatic breathing, muscle stretch gymnastics, and walking. The 6-minute walking test distance increased from 170 m to 280 m. The minimum SpO2 during the 6-minute walking test increased from 88% to 91%. (O2 3 L/m) After discharge, she continued to receive home care from a visiting nurse specialized in respiratory medicine and 24 hour-monitoring of O2-compliance at home. She has not experienced acute exacerbation or re-hospitalization for 1 year. We conclude that home care service is effective to maintain stable conditions such as state of breathing, SpO2, vital signs, and activities of daily living for elderly COPD outpatients.  相似文献   
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70.
Meconium disease (MD) results in intestinal obstruction in the neonate where tenacious meconium is found in the distal ileum and proximal colon. The obstructive symptoms improve at several days of age after some of the meconium is passed. We observed premature infants with MD who underwent ileostomy for intestinal obstruction due to tenacious meconium. Afterward, meconium was passed well and the clinical symptoms improved. After closing the ileostomy, growth and defecation became normal. The MD in our cases was documented by histologic changes in the maturation of ganglion cells observed at the time of ileostomy creation and closure. For an objective evaluation of the maturation of intestinal ganglion cells (IGC), we attempted to distinguish immature from mature cells by the expression of cathepsin D. We examined the distribution of cathepsin D in IGC in patients with MD to test the hypothesis that ganglion-cell immaturity might be related to MD. In ganglion cells at the time of ileostomy, cathepsin D was detected in the perinuclear cytoplasm (immature staining pattern), while at the time of ileostomy closure it was detected in intense granules throughout the cytoplasm (mature staining pattern). We propose that it would be possible to evaluate the maturation of IGC by the intracellular distribution of cathepsin D in MD and suggest that immaturity of IGC might be the cause of MD. Accepted: 28 June 1999  相似文献   
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