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91.
Oxidative stress (OS) mechanisms are speculated to play a significant role in nickel-induced toxic effects and their carcinogenic potency. Although nickel-induced oxidative damage in somatic tissues is well demonstrated, evidence of the involvement of a similar mechanism(s) in nickel-induced testicular dysfunction and associated genotoxic effects is scarce. Hence, the present study aimed to investigate the nickel-induced OS response in testis and the associated genotoxic implications in vivo. Initially, the toxicity profile of nickel chloride was determined in adult albino mice (CFT-Swiss) following administration (intraperitoneal) of single doses. Subsequently, multiple sublethal doses (1.25, 2.5, and 5.0 micromol/100 g of body weight per day for 3 days) were used to characterize effects on testicular histoarchitecture, lipid peroxidation (LPO) in testis (homogenates, microsomal or mitochondrial fractions) and epididymal sperm, DNA damage, induction of apoptosis in testis, and incidence of sperm head abnormalities. Although short-term doses of nickel induced only a minimal LPO response, multiple doses elicited a moderate (15% to 30%) increase in LPO in whole homogenates and higher dose-related increases in both mitochondrial (20% to 50%) and microsomal fractions (25% to 60%). This was associated with a significant increase in DNA damage in the testis as evidenced by increased single-strand breaks (fluorimetric analysis of DNA unwinding assay). Further, at higher doses, nickel-induced apoptosis was demonstrable in the testis biochemically. Although caudal sperm counts determined at all sampling weeks showed no alterations, analysis for head abnormalities revealed a nearly 3- to 4-fold increase in the percentage of abnormal sperms among the nickel-treated males during the first 3 weeks. Furthermore, mating of nickel-treated (2.5 micromol/100 g of body weight per day for 5 days) males sequentially for a period of 5 weeks with untreated females resulted in a significant increase in male-mediated dominant lethal-type mutations (the frequency of dead implantations) during the first 3 weeks, suggesting a stage-specific effect on postmeiotic germ cells. These findings suggest that testicular toxicity of nickel compounds may be related to enhanced production of reactive oxygen species, probably mediated through oxidative damage to macromolecules, including damage to DNA.  相似文献   
92.
93.
Plant-derived phenolic compounds manifest many beneficial effects and can potentially inhibit several stages of carcinogenesis. In the present study, we investigated the efficacy of Emblica officinalis (E. officinalis) polyphenol fraction (EOP) on the induction of apoptosis in mouse and human carcinoma cell lineses and its modulatory effect on N- nitrosodiethylamine (NDEA) induced liver tumors in rats. The results indicate that EOP treatment could induce apoptosis in Dalton's Lymphoma Ascites (DLA) and CeHa cell lines At 200 microg/ml dose EOP induced membrane blebbing, chromatin condensation and intenucleosomal breaks as evident from the morphology and DNA ladder pattern obtained in gel electrophoresis. The results also suggested that EOP treatment could decrease the liver tumour development induced by NDEA. Animals administered (oral) with NDEA (0.02%, 2.5 ml/rat, 5 days a week, 20 weeks) developed visible liver tumours by the end of the 20th week and the liver weight raised to 5.2 +/- 1.1 g/ 100 g body weight. Only 11% of the animals treated with EOP (60 mg/kg, oral, 5 days a week for 20 weeks) developed visible liver tumours by this period and the liver weights were reduced to 3.2 +/- 0.7 g/ 100 g body weight. gamma-glutamyl transpeptidase activity was raised to 88.4 +/- 16.2 U/l in serum of NDEA treated group was reduced to 48.4 +/- 14.8 U/l by EOP treatment. Elevated levels of serum alkaline phosphatase (ALP), glutamate pyruvate transaminase (GPT), bilirubin, liver glutathione S-transferase (GST) and glutathione (GSH) in the NDEA administered group were significantly reduced by EOP treatment. The EOP was found to scavenge superoxide and hydroxyl radicals and inhibit lipid peroxidation in vitro. EOP also inhibited DNA topoisomerase I in Saccharomyces cervisiae mutant cell cultures and the activity of cdc25 tyrosine phosphatase.  相似文献   
94.
To determine whether the vasoocclusive severity of homozygous sickle cell (SS) disease is influenced by cellular dehydration, we correlated the incidence of painful crisis with steady-state measurements of red cell hydration. Sixteen children with SS disease were followed for 3.3 to 8 years (mean, 6.8 years), and a single crisis rate was calculated for each patient. At the time of well visits, cellular hydration was assessed by measuring cell deformability, the percentage of red cells with a density greater than or equal to 1.1056 g/mL, and the percentage of irreversibly sickled cells (ISC). The incidence of painful crisis showed a strong positive correlation with Omax, a deformability measurement reflecting cellular hydration (r = .84, P less than .002), and with hemoglobin concentration (r = .59, P = .04). That is, higher crisis rates were observed in patients with less dehydrated, more deformable red cells and also in patients with higher hemoglobin concentrations. Furthermore, cell deformability and hemoglobin concentration were independent predictors of the incidence of painful crisis, which is consistent with separate effects of these two red cells parameters on vasoocclusive severity.  相似文献   
95.
Five children with cystic fibrosis complicated by hepatic cirrhosis received liver grafts. They all had portal hypertension with varices and three had variceal bleeding; respiratory function was only moderately impaired, but four were colonised with pseudomonas and one with aspergillus. Liver transplantation was well tolerated and there was no increase in respiratory or other early postoperative complications. Four of the children were fully well from 14 to 35 months after transplantation; the most recently transplanted had problems from a biliary stricture. In spite of the need for immunosuppression there was no increase in infection and respiratory function improved or remained stable. Once the children were stabilised after transplantation their nutrition and general health were greatly improved.  相似文献   
96.
Picroliv, an iridoid glycoside mixture prepared from the roots and rhizomes of Picrorhiza kurroa was found to be an effective inhibitor of hepatocarcinogenesis induced by N-Nitrosodiethylamine (NDEA) in rats. Animals administered with NDEA had large hepatic nodules and the liver weight was increased to 6.17 +/- 1.0 g/100 g.b.wt. as compared to the normal liver weight 2.84 +/- 0.08 g/100 g.b.wt. Picroliv administration (200 mg/Kg.b.wt) reduced the liver weight to 3.30 +/- 0.23 g/100 g.b.wt. Oral administration of Picroliv reduced NDEA-induced elevation of gamma-glutamyltranspeptidase (gamma-GT) in serum and liver to that of normal rats. Moreover, elevated levels of bilirubin, alkaline phosphatase (ALP), glutamatepyruvate transaminase (GPT) and serum peroxides were also found to be significantly reduced by Picroliv administration. Similar observations were noticed in glutathione (GSH) and glutathione S-transferase (GST) levels. Histopathological analysis of the Picroliv treated rat liver resembles that of a normal liver except for a few alterations such as hepatocytomegalia and karyomegalia in some focii. The results are indicative of the chemopreventive potential of Picroliv against chemically-induced liver tumours.  相似文献   
97.
We carried out a randomized, placebo-controlled, double-blinded trial to evaluate the effect on morbidity of high dose oral vitamin A, given on hospital admission to 592 children aged 1–59 months with moderate and severe pneumonia. Severely underweight children were not included, but 45% were moderately underweight. The vitamin A and placebo groups were comparable in baseline characteristics. Four patients died. Among all of the surviving children, no differences were found regarding mean time for normalization of fever, respiratory rate and time of hospitalization. Stratification for moderate malnutrition, degree of pneumonia, age and sex revealed moderately malnourished vitamin A-supplemented children to have a shorter time of hospitalization ( p = 0. 04), due to an effect in females aged > 12 months ( p = 0. 02) and females with very severe pneumonia ( p = 0. 048). This study indicates that, in developing countries like Vietnam, supplementation with vitamin A in children with pneumonia could shorten the recovery rate in the ones that are undernourished, especially females > 1 y old.  相似文献   
98.
We applied the technique of ooplasmic elongating spermatid injection to the treatment of non-obstructive azoospermia. Mature oocytes were injected with elongating spermatids isolated from testicular biopsy material obtained from 13 non-obstructed azoospermic men. Seventy-three oocytes were successfully injected with elongating spermatids and were then cultured for 36 h. At 13 h post-injection 68 oocytes were found to be activated and 52 of them were fertilized. Forty-one 2- to 4-cell stage embryos developed from normally fertilized oocytes were transferred. At least two embryos were transferred to each female partner. Two pregnancies were achieved. Elongating spermatid injection may have a role in the treatment of non-obstructive azoospermia.   相似文献   
99.
PURPOSE: Analyzing metastatic prostate cancer tissue is of considerable importance in evaluating new targeted agents, yet acquiring such tissue presents a challenge due to the predominance of bone metastases. We assessed factors predicting a successful tumor harvest from bone marrow biopsies (BMBx) in castration-resistant metastatic prostate cancer patients. MATERIAL AND METHODS: Data from Cancer and Leukemia Group B study 9663 were reviewed. Bone marrow biopsies were obtained from 184 patients who underwent an office-based, unguided bone marrow biopsy of the posterior iliac crest. RESULTS: Forty-seven of the 184 patients (25.5%) had a positive bone marrow biopsy. When considered in a multivariate logistic regression analysis, lower hemoglobin levels, higher alkaline phosphatase, and higher lactate dehydrogenase levels were associated with a higher likelihood of a positive BMBx. The median survival time was 11 months (95% confidence interval, 8.0-14) among patients with a positive BMBx compared with 23 months (95% confidence interval, 19-27) with a negative BMBx. The median time to progression and time to prostate-specific antigen progression-free survival were also significantly decreased among positive BMBx patients. No patients with a positive BMBx survived beyond 3 years, whereas 11 of the 137 patients with a negative BMBx survived beyond 5 years. DISCUSSION: Using common laboratory values, a specific patient cohort can be defined from whom the yield of a nonguided BMBx would be high enough to justify this approach. For studies that require broader entry criteria, a more directed approach with image guidance is recommended.  相似文献   
100.
BACKGROUND: Autoantibodies with anti-U specificity, usually in combination with autoantibodies of other specificities, have occasionally been identified in association with autoimmune hemolytic anemia. A case of life-threatening autoimmune hemolytic anemia, characterized by several atypical features, including apparent intravascular hemolysis associated with an IgG2 anti-U, reticulocytopenia, and bone marrow dyserythropoiesis is described. CASE REPORT: A 36-year-old man with a severe case of acute-onset autoimmune hemolytic anemia was admitted to another hospital; he had a hematocrit of 15 percent, elevated bilirubin and lactate dehydrogenase, and positive direct and indirect antiglobulin tests. He received 7 units of incompatible red cells without improvement in hematocrit, and he was transferred to University Hospitals of Cleveland (OH). He was jaundiced and became syncopal in the sitting position. His serum was reddish pink; he had a hematocrit of 11.8 percent and a reticulocyte count of 2.5 percent. No spherocytes were observed in the peripheral blood smear. Shortly after admission, the hematocrit fell to 6.9 percent. He was given 3 units of “least-incompatible” red cells and was started on prednisone, with little improvement. An IgG2 autoanti-U was detected in his serum. Seven units of U- red cells were transfused over the next 4 days. The hematocrit improved to 23 percent and continued to rise without further transfusion. A bone marrow examination, initially revealing erythroid hyperplasia accompanied by dyserythropoiesis, became morphologically normal. Drug studies failed to show evidence of drug-related hemolysis. He remains well 2 years after discharge without evidence of recurrent hemolysis. CONCLUSION: Severe life-threatening autoimmune hemolytic anemia, in this instance induced by an autoanti-U, may be associated with IgG2 autoantibody and characterized by apparent intravascular hemolysis and bone marrow dyserythropoiesis. Early treatment with U- blood, in addition to steroids, may be beneficial.  相似文献   
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