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Oral Diseases (2012) 18 , 206–212 Objectives: The effect of growth differentiation factor 5 and bone morphogenetic protein 2 on human periodontal ligament‐derived cells was investigated with special reference to tendo/ligamentogenesis‐related markers. Materials and Methods: Effects of each factor were analyzed by quantitative PCR for scleraxis and tenomodulin and by western blotting for scleraxis. After exposure to those factors, STRO‐1‐positive and STRO‐1‐negative fractions of human periodontal ligament tissues were isolated with an immunomagnetic cell sorting system, and the expression of scleraxis in each fraction was analyzed by western blotting. Non‐separated crude cells were used as a control. Results: Growth differentiation factor 5 and bone morphogenetic protein 2 did not increase alkaline phosphatase activity in crude periodontal ligament‐derived cells. Growth differentiation factor 5, but not bone morphogenetic protein 2, increased the expression of scleraxis in crude, STRO‐1‐positive and STRO‐1‐negative periodontal ligament‐derived cells. The expression of scleraxis in STRO‐1‐positive periodontal ligament‐derived cells was significantly less compared to that in crude P2 and STRO‐1‐negative periodontal ligament‐derived cells. Conclusion: Growth differentiation factor 5 induced the expression of scleraxis and may enhance tendo/ligamentogenesis in human periodontal ligament‐derived cells. The expression of scleraxis was higher in STRO‐1‐negative fraction, suggesting more differentiated state of the cells.  相似文献   
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Ohno K  Hattori T  Kagami H  Ueda M 《Oral diseases》2007,13(2):158-162
OBJECTIVE: The mechanism underlying the onset and development of autoimmune diseases such as Sjogren's syndrome is not well understood. Here, we examined the effects of preceding inflammation of the salivary gland at the onset of autoimmunity against the salivary gland. MATERIALS AND METHODS: One side of the submandibular gland duct was ligated in mice and the effect on the contralateral gland was investigated. After histological evaluation with hematoxylin and eosin staining, the presence of autoantibodies and immune compounds was examined. RESULTS: In all five strains of mice that were used, the salivary gland of the ligated side showed severe inflammation and atrophic change. In two mouse strains (SJL/J and PL/J), mild sialadenitis was observed on the non-ligated side 8 weeks after ligation. Autoantibodies reacting to the salivary gland were detected in three mouse strains (C3H/He, SJL/J, and PL/J). Immune complex was also detected in the duct basement membrane. CONCLUSION: The results indicate that the autoimmune mechanism is activated by the transient inflammation in the salivary gland under a specific genetic background.  相似文献   
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Atypical hemolytic uremic syndrome (aHUS) is rare and comprises the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Recently, abnormalities in the mechanisms underlying complement regulation have been focused upon as causes of aHUS. The prognosis for patients who present with aHUS is very poor, with the first aHUS attack being associated with a mortality rate of ~25 %, and with ~50 % of cases resulting in end-stage renal disease requiring dialysis. If treatment is delayed, there is a high risk of this syndrome progressing to renal failure. Therefore, we have developed diagnostic criteria for aHUS to enable its early diagnosis and to facilitate the timely initiation of appropriate treatment. We hope these diagnostic criteria will be disseminated to as many clinicians as possible and that they will be used widely.  相似文献   
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Paraffin sections of liver on 227 autopsy cases were stained by a modified orcein method of Shikata et al (14) in order to detect hepatitis B surface antigen (HBsAg). Blood of all the 227 cases obtained at autopsy were tested for HBsAg by immune adherence hamagglutination method (7) and for antibody to HBsAg (anti-HBs) by passive hemagglutination method (6). Cases of seropositive in HBsAg but negative in anti-HBs group showed orcein-positive hapatocyte in 13 (68%) of 19 cases of cirrhosis with hepatoma, in 2 (67%) of 3 cases of cirrhosis without hepatoma, and in 2 (67%) of 3 cases of non-cirrhotic neoplastic diseases other than hepatoma. Cases of seronegative in both HBsAg and anti-HBs group showed orceinpositive hepatocyte in 4 (17%) of 24 cases of cirrhosis with hepatoma, in 2 (11%) of 19 cases of cirrhosis without hepatoma, and in 3 (5%) of 60 cases of non-cirrhotic neoplastic diseases other than hepatoma. Cases of seronegative in HBsAg but positive in anti-HBsAg but positive in anti-HBs group showed orcein-positive hepatocyte in 1 (17%) of 6 cases of cirrhosis with hepatoma and in 1 (5%) of 21 cases of non-cirrhotic neoplastic diseases other than hepatoma. Cases of seropositive in both HBsAg and anti-HBs group showed orcein-positive hepatocyte in 1 (33%) of 3 cases of cirrhosis with hepatoma. No orcein-positive hepatocyte was detected in cases of hepatoma without cirrhosis and in cases of non-cirrhotic non-neoplastic diseases in any serological groups.  相似文献   
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BACKGROUND: Primary pulmonary hypertension (PPH) is a rare disease characterized by progressively increased resistance of the pulmonary arteries associated with vascular remodeling. Infiltration of inflammatory cells in affected vessels is a common pathological finding. Monocyte chemoattractant protein-1 (MCP-1) is recognized as a potent chemotactic and activating factor for monocytes and leukocytes, but its significance in PPH is unclear. METHODS AND RESULTS: Serum MCP-1 concentrations were measured in 16 PPH patients and the results were compared with those in 16 normal controls. MCP-1 concentrations in PPH patients (265.6+/-29.5 pg/ml) were significantly elevated compared with those in normal controls (119.6+/-6.9 pg/ml, p<0.0001). In 9 patients (3 men, 6 women; mean age, 29+/-3 years), repeated MCP-1 and hemodynamic measurements were performed prior to and during intravenous epoprostenol therapy. During a mean follow-up period of 7+/-1 months, MCP-1 concentrations were significantly reduced (288.8+/-122.8 to 185.9+/-117.5 pg/ml, p<0.01). CONCLUSIONS: Circulating MCP-1 concentrations are increased in PPH patients, but can alleviated by chronic intravenous epoprostenol therapy. The increase in MCP-1 might be one of the important factors responsible for the disease development in patients with PPH.  相似文献   
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BACKGROUND: The manner in which Helicobacter pylori is transmitted is of fundamental importance when considering strategies for its control, yet, to date, the exact mode of transmission remains uncertain. METHODS: The seroprevalence of H. pylori in a relatively isolated rural town in Japan (A-town) was examined to analyse the H. pylori infection route. The immunoglobulin G antibodies against H. pylori in 1684 subjects who had received public health examinations in A-town were determined with an enzyme-linked immunosorbent assay. The seroprevalence was compared in five areas according to the water source. The possibility and frequency of intrafamilial infection was analysed by comparing the seroprevalence among family members residing in the same home. RESULTS: The seroprevalence of H. pylori did not differ significantly between the five areas examined. Seropositivity was significantly more common in the children whose mothers were seropositive (45.0%, 27/60) than in the children whose mothers were seronegative (10.0%, 2/20; odds ratio (OR) = 7.36, P = 0.0036, 95% confidence interval (CI) = 1.57-34.59). Seropositivity was significantly more common in the children whose older siblings were seropositive (55.0%, 22/40) than in the children whose older siblings were seronegative (23.5%, 20/85; OR = 3.97, P = 0.00051, 95% CI = 1.79-8.84). There was no significant relationship in seroprevalence between children and fathers, grandchildren and grandfathers, grandchildren and grandmothers, or within couples. Seropositivity was significantly more common in the adolescents who had attended a nursery school (44.4%, 20/45) than in the adolescents who had not attended a nursery school (25.6%, 109/426) (OR = 2.33, P = 0.0070, 95% CI = 1.24-4.36). CONCLUSIONS: The acquisition of H. pylori infection occurs by close contact with infected individuals in early childhood, especially via contact with infected mothers and other infected children.  相似文献   
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