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21.
Like gastric and intestinal mucins, the tight junction proteins called claudins can be used to determine the differentiation of gastric mucosa. We investigated the expression of claudins in gastric cancer and proposed a new claudin-based gastric cancer classification system. The expression of gastric (claudin-18) and intestinal (claudin-3 and claudin-4) claudins in non-neoplastic gastric mucosa (with intestinal metatplasia [IM], 78 cases; without IM, 88 cases) and 94 gastric cancers was analyzed immunohistochemically, as was the expression of gastric (MUC5A and MUC6) and intestinal (CD10 and MUC2) mucins. Heterogeneous expression of claudin-3, claudin-4 and claudin-18 was detected in advanced gastric cancer; however, there was no significant association between the claudins and the clinicopathological parameters. These gastric cancer tissues were also subclassified into claudin-based phenotypes: gastric claudin (G-CLDN), 28 cases (30%); intestinal claudin (I-CLDN), 41 cases (44%); and unclassified claudin (U-CLDN), 25 cases (26%). Interestingly, the U-CLDN gastric cancers had worse malignancy grades, not only in size and invasiveness but also in potential metastatic ability and patient outcome. Although the mucin-based gastric cancer classification was also assessed, no significant correlation was found between mucin production and clinicopathological parameters. These observations suggest that loss of claudin expression may enhance the grade of malignancy of gastric cancer in vivo. Classification of gastric cancers using gastric and intestinal claudins is a good biomarker for assessing the risk of poor prognosis.  相似文献   
22.

Purpose

Under the assumption that tryptophan (TRP) metabolism may be modulated by the intensity, duration, and total exercise/energy expenditure of the ultra-marathon, we evaluated the changes in two major TRP metabolic pathway substances [serotonin (5-HT) and kynurenine (KYN)] during a two-day ultra-marathon race.

Methods

Blood was sampled at three different time points: before the race (baseline), after running 45 km on the first day, and after running 135 km on the second day.

Results

Serum TRP concentrations decreased in proportion to the distance covered, and the levels after running 135 km were significantly lower than at baseline and after running 45 km. Serum serotonin (5-HT) concentrations increased significantly after running 45 km but reduced towards baseline levels after running 135 km. Serum kynurenine (KYN) concentrations hardly changed after running 45 km but increased significantly after running 135 km compared with after running 45 km values. Serum FFAs levels increased significantly after running 45 km compared with baseline values, and they elevated even further after running 135 km. Serum albumin concentrations reduced significantly after running 45 km but remained at almost the same level after running 135 km. Serum 5-HT levels tended to be consistently correlated to the completion times on the first and second days.

Conclusions

Serum 5-HT concentrations are known to be associated with central fatigue, and may predict exercise performance. KYN levels appeared to reflect the intensity of physical exercise, and its pathway may play a role in reactive oxygen species scavenging systems during a long-duration exercise.
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The purposes of this study were as follows: to compare premorbid IQ with present IQ in patients with more severe anorexia nervosa restricting type (AN-R) and to investigate the relationship between decreasing IQ and symptoms in patients with severe AN-R. Twenty-two participants were recruited (12 were AN-R patients; 10 were healthy controls). The average BMI in AN-R patients and healthy controls was 12.65 and 19.82, respectively. We assessed the outcomes using the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III), the Japanese Adult Reading Test, The Eating Disorders Inventory-2 (EDI-2), Beck Depression Scale-2 (BDI-2) and State-Trait Anxiety Index. In two-way ANOVA, there were significant interactions for the FIQ and PIQ. Only in the AN-R group, a significant single main effect of time was evidenced for the FIQ and PIQ. In the AN-R group, a significantly high positive correlation was found between changes in the PIQ and the body dissatisfaction subscale of the EDI-2. These findings raise the possibility that in patients with severe AN-R, an excessive decrease in body weight induces decreased PIQ; as a result, they have worse dissatisfaction with their body shape.  相似文献   
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Mitochondrial DNA (mtDNA) is inherited solely along the matriline, giving insight into both ancestry and prehistory. Individuals of sub-Saharan ancestry are overrepresented in sprint athletics, suggesting a genetic advantage. The purpose of this study was to compare the mtDNA haplogroup data of elite groups of Jamaican and African-American sprinters against respective controls to assess any differences in maternal lineage. The first hypervariable region of mtDNA was haplogrouped in elite Jamaican athletes (N=107) and Jamaican controls (N=293), and elite African-American athletes (N=119) and African-American controls (N=1148). Exact tests of total population differentiation were performed on total haplogroup frequencies. The frequency of non-sub-Saharan haplogroups in Jamaican athletes and Jamaican controls was similar (1.87% and 1.71%, respectively) and lower than that of African-American athletes and African-American controls (21.01% and 8.19%, respectively). There was no significant difference in total haplogroup frequencies between Jamaican athletes and Jamaican controls (P=0.551 ± 0.005); however, there was a highly significant difference between African-American athletes and African-American controls (P<0.001). The finding of statistically similar mtDNA haplogroup distributions in Jamaican athletes and Jamaican controls suggests that elite Jamaican sprinters are derived from the same source population and there is neither population stratification nor isolation for sprint performance. The significant difference between African-American sprinters and African-American controls suggests that the maternal admixture may play a role in sprint performance.  相似文献   
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The present study was undertaken to examine the effect of mitochondrial haplogroups on aerobic and anaerobic performance phenotypes such as maximum oxygen consumption, muscle power, and muscle mass. We recruited 474 healthy Japanese individuals and measured their physical performance phenotypes such as peak oxygen uptake, muscle power, and muscle mass. The genotypes for 186 polymorphisms in the mitochondrial DNA were determined, and the haplotypes were classified into 2 macrohaplogroups (i. e., N and M) and 12 haplogroups (i. e., F, B, A, N9a, N9b, M7a, M7b, G1, G2, D4a, D4b, and D5). When we compared the 2 major Japanese macrohaplogroups, leg extension power (P=0.0395), leg extension power based on body weight (P=0.0343), and vertical jump performance (P=0.0485) were significantly higher in subjects with mitochondrial macrohaplogroup N than in those with macrohaplogroup M. However, peak oxygen uptake was similar between the 2 groups. When we analyzed the 12 haplogroups, all of the measured parameters were similar among them. In conclusion, mitochondrial macrohaplogroup N may be one of the determinant factors of anaerobic physical performance phenotype such as muscle power.  相似文献   
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This study evaluated the dentinal composition and Knoop hardness measurements of the cavity floor following the removal of carious dentin by the Carisolv chemo-mechanical caries removal system, in vitro. The carious dentin of 25 extracted human teeth was removed by using Carisolv for one minute with instruments and excavation that was performed until the gel was clear. Caries removal with a sharp explorer was verified according to the color and hardness of the lesion, then, by means of DIAGNOdent. Atomic analysis of treated cavities was performed by energy dispersive x-ray spectroscopy (SEM-EDX) and the Knoop hardness number (KHN) of the cavity floor was determined. Surface characteristics were observed by the scanning electron microscope (SEM). Adjacent sound dentin was used as a control reference. No significant differences were found between the quantities of calcium content (Ca weight %), phosphorus content (P weight %) and the Ca/P weight ratio of Carisolv cavities with that of the adjacent, sound dentin (p<0.01). KHN of the Carisolv cavity floor was almost similar to that of the adjacent sound dentin. SEM analysis revealed an extremely rough or irregular surface, and there remained a minimal debris-like smear layer; most of the dentinal tubules were opened. The results indicated that Carisolv does not produce any adverse side effects on dentinal compositions of the treated cavities. The possibility of remaining residual softened dentin was also minimal in this study.  相似文献   
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BACKGROUND: Mild hypothermia has been proposed as a means of providing cerebral protection after traumatic brain injury. However, hypothermia has been shown to alter not only physiologic but also pharmacologic responses. The purpose of this study was to investigate whether mild hypothermia (3-4 degrees C temperature reduction) could alter cerebral vasodilation induced by inodilators, which are characterized by having an inotropic effect in addition to a vasodilatory effect. Isoproterenol (a beta-adrenergic receptor agonist), colforsin dapropate (an adenylate cyclase stimulant), and amrinone (a phosphodiesterase inhibitor) were chosen as inodilators. METHODS: The cranial window technique, combined with microscopic video recording, was used. Forty-eight cats were randomly assigned to either a normothermic or a hypothermic group (33 degrees C). Isoproterenol, colforsin dapropate, or amrinone was topically applied in the cranial window and the diameter of pial arterioles was measured. RESULTS: Topical administration of isoproterenol, colforsin dapropate, and amrinone produced a significant dilation in a dose-dependent manner during normothermia. The vasodilation induced by these inodilators was not affected by mild hypothermia. CONCLUSION: The vasodilation induced by topical administration of isoproterenol, colforsin dapropate, and amrinone was not affected by mild hypothermia.  相似文献   
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