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61.
OBJECTIVES: In a variety of cancers, several polymorphisms of the tumor necrosis factor (TNF) genes have been reported to result in different clinical outcomes. We investigated whether a polymorphism of the TNF gene is associated with a susceptibility to bladder cancer and its disease status. METHODS: Polymorphisms in the TNF-alpha gene promoter (-308 bp) and the NcoI site in the first intron of the TNF-beta gene were analyzed in 141 Japanese patients with bladder cancer and 173 Japanese controls by polymerase chain reaction-restriction fragment length polymorphism. The correlations between the polymorphisms of the TNF genes and the clinicopathological features were analyzed. RESULTS: The number of cases and controls with TNF-alpha2 was too small to be assessable. In contrast, the TNF-beta1/2 genotype at the NcoI site in the first intron conferred a 1.71-fold increased risk of bladder cancer compared to the TNF-beta2/2 genotype. In the bladder cancer group, patients with the TNF-beta1 allele had a significantly higher risk for a high-grade tumor (grade 3) or carcinoma in situ (CIS) than those without the TNF-beta1 allele. Moreover, in the superficial bladder cancers, patients with the TNF-beta1 allele showed a significantly higher intravesical recurrence rate than those without the TNF-beta1 allele. CONCLUSION: This polymorphism in the TNF-beta gene appears to be associated with tumor occurrence and disease status, such as the tumor grade and the presence of CIS. Further study with an increased sample size is warranted.  相似文献   
62.
A new rat model for multifocal cerebral thrombosis has recently been reported (Tani et al. , 1994; 1995). Ultrastructural changes in the cerebral neocortex in the acute phase were investigated in order to characterize the early pathological events in this model. A bolus injection of alkaline phenytoin solution (pH 10.8) into one internal carotid artery in the rat caused severe endothelial injury accompanied by thrombosis in the cerebral vasculature within 5 minutes, and severe oedema of the ipsilateral hemisphere within an hour. Cerebral water content was measured by the simple dry–wet method, and cerebral surface area and the surface area and volume of the ischaemic zone were measured using computer-aided image analysis. Good correlations were demonstrated between cerebral water content and cerebral surface area, and between the surface area and volume of the ischaemic zone. We report here that quantitative evaluation of acute cerebral damage induced by phenytoin solution is possible with high reliability using simple image analysis.  相似文献   
63.
64.
Background. Esophageal stenosis and hand deformity are serious complications of recessive dystrophic epidermolysis bullosa that influence the prognosis of patients. To control such complications we have used surgical treatments with favorable results. Additional objectives were to summarize the results of long-term follow-up. Methods. Six patients with esophageal stenosis and nine patients (13 hands) with hand deformity (contracted fingers, mitten-like deformity) were treated surgically after anemia and malnutrition were corrected by intravenous iron infusion, high-energy diet, and blood transfusion. As intubation was contraindicated, topical anesthesia was used (eg., lidocaine spray to the nasopharyngeal mucosa for esophageal dilatation and brachial block, ketamine drip, and nitrous oxide inhalation for reconstruction of contracted fingers). We established a new method for esophageal dilatation using a microvasive rigiflex balloon catheter. This catheter was advanced to the stenotic area under radiography and then expanded by injecting contrast medium into the balloon. For reconstruction of hand deformities, the epidermal glove was initially peeled off, and then the combined digits separated carefully by hand, if the release of the contracture was not sufficient, a skin incision was made avoiding injury to nerves and blood vessels. Any skin defects that appeared after the release of the contracture were covered with skin grafts taken from the abdominal wall. K-wire fixation was used to maintain the extended position of the fingers. Three weeks after the operation, the K-wires were removed and rehabilitation was commenced. Results. The esophageal stenosis was successfully dilated with the balloon catheter; in all six cases the dysphagia was relieved immediately. There was no recurrence in any of the patients on long-term follow-up. After reconstruction of the hand, daily activity improved in 12 of the 13 hands. The remaining hand was difficult to reconstruct due to severe mutilation and bone deformity. During follow-up, 6 of the 12 hands maintained successful reconstruction, whereas the remaining 6 hands showed slight to moderate recontraction of the fingers. Conclusion. Esophageal dilatation with a balloon catheter is safer and has fewer side effects compared to other surgical procedures. This method can provide favorable results and can be carried out repeatedly in a short time. Daily and social activities of patients can be improved upon reconstruction of hand deformities.  相似文献   
65.
Abstract— We investigated the metabolism of tolbutamide by using synthetic 1-butyl-3-(p-formylphenyl)sulphonylurea (ATB), an intermediate in the metabolic pathway of tolbutamide. ATB (40 mg kg?1) administered intravenously to rabbits was oxidized to 1-butyl-3-(p-carboxyphenyl)sulphonylurea (CTB) and also reduced to 1-butyl-3-(p-hydroxymethylphenyl)sulphonylurea (HMTB). Therefore, it is likely that in the metabolism of tolbutamide, the oxidation of HMTB to ATB involved the reverse reaction, suggesting the reduction of ATB to HMTB. The oxidation of ATB to CTB was inhibited by disulfiram pretreatment. ATB was detected in the blood following intravenous administration of HMTB in rabbits pretreated with disulfiram. These results, confirm that ATB is an intermediate in the oxidative metabolism of tolbutamide in the rabbit.  相似文献   
66.
A 54-year-old woman who was being treated with 10 million units (mu) of natural interferon (IFN)-α per day for chronic active hepatitis C at a local clinic, developed coma on the fourth day of treatment. On admission to Yamagata University Hospital, she was still in a state of semicoma with severe hyponatraemia (122 mEq/L) and hypochloraemia (89 mEq/L). After the administration of electrolytes, her condition improved remarkably. Endocrinological loading tests showed a hypofunction of the anterior pituitary gland. In consideration of these results, and her past experiences of haemorrhage during childbirth and subsequent amenorrhoea, we diagnosed her illness as a coma as a result of Sheehan's syndrome which had become overt during IFN therapy. She recovered completely after treatment with hydrocortisone and 1-thyroxine.  相似文献   
67.
Abstract We treated a patient who had previously undergone a hepatic resection for ruptured hepatocellular carcinoma (HCC) but developed a solitary peritoneal recurrence at the site of the incision 8 years and 9 months later. Since no other recurrence was evident, we resected the tumour. The primary tumour was 2.5 cm in size and histological examination revealed HCC without any histological risk factors for intrahepatic recurrence. The peritoneal tumour consisted of less differentiated cancer cells than those found in the primary tumour. The positive rates of Ki-67 were 10% in the primary tumour and 23.3% in the peritoneal recurrence. The DNA indexes in both tumours were considered to be identical.
The comparison between the primary and peritoneal tumours suggested that the histological differentiation and proliferation activity can change after recurrence, in spite of consistent DNA ploidy contents. Clinically, a patient who undergoes a hepatic resection for ruptured HCC can survive for a long time, such as 10 years, if they have good liver function and small HCC without any histological risk factors for intrahepatic recurrence. However, since late recurrence is possible, a follow up for as long as 10 years is recommended.  相似文献   
68.
Abstract— Saiboku-To is an anti-asthmatic herbal remedy which consists of ten herbal extracts. To investigate the clinical relationship between the effects and chemical components of Saiboku-To, a simple and sensitive high-performance liquid chromatographic method (HPLC) for determination of magnolol, one of the major urinary products, was developed. Organic solvent extraction of urinary magnolol was conducted by diatomaceous earth column rapid-flow fractionation using ethanol/dichloromethane (8/92, v/v). Recovery rates of magnolol were more than 99% with coefficient of variations less than 6% in the concentration range 9·7–970 ng mL?1. Subsequent HPLC determination of magnolol was achieved using a conventional silica-gel column, a mobile phase mixture of acetic acid/diethyl ether/n-hexane (0·2/17·0/82·8, v/v), and a UV-absorption detector set at 290 nm. Calibration was on the basis of peak height ratio between magnolol and flavone as an internal standard. The method was used to demonstrate excretion profiles of magnolol in healthy and asthmatic subjects following single administration of Saiboku-To.  相似文献   
69.
Abstract— We aimed to clarify the relationship between drug dissociation (sulphisomidine) and its direct transport from the nasal cavity to the cerebrospinal fluid (CSF). Rat nasal cavities were perfused in a single pass system with buffers (pH 5·5, 6·5, 7·4, 8·7 and 9·4). Plasma and CSF were collected and the concentration of sulphisomidine was measured. Nasal clearance increased with the increase in the un-ionized fraction of the drug. The ratio of the drug concentration in CSF to that in the nasal perfusion fluid (the index of the degree of the drug transport from the nasal cavity to CSF), was changed in accordance with the un-ionized fraction of drug. These results show that both the nasal absorption and the drug transport conform to the pH partition theory.  相似文献   
70.
It is widely accepted that thrombocytopenia associated with liver cirrhosis is caused by increased platelet destruction in the enlarged spleen, but this issue has not yet been analysed sufficiently in terms of platelet production. Thrombopoietin is produced mainly in the liver and strongly promotes platelet production. We studied serum thrombopoietin and the levels of its mRNA in liver tissue of cirrhotic patients and also in a rat model of liver cirrhosis. Furthermore, to clarify the influence of the spleen, we investigated thrombopoietin mRNA in splenectomized rats. The serum thrombopoietin level in humans with liver cirrhosis was not significantly reduced instead of thrombocytopenia. The expression of thrombopoietin mRNA in liver tissue decreased with the progression of liver cirrhosis in both patients and the rat model and no compensatory expression was observed in other organs or nonparenchymal cells. The level of thrombopoietin mRNA did not differ significantly in splenectomized cirrhotic rats before or after administration of dimethylnitrosamine, but was lower than that in splenectomized rats without cirrhosis. We conclude that thrombocytopenia in liver cirrhosis is caused not only by platelet destruction but also by decreased platelet production, perhaps due to reduction of thrombopoietin mRNA in the liver.  相似文献   
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