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1.
Summary: In situ hybridization of mRNA for collagen IV, collagen VI, stromelysin (MMP-3) and TIMP1 was examined in renal biopsy specimens from patients with IgA nephropathy (IgAN) or diabetic nephropathy with various degrees of tissue damage. The majority of cells in the glomeruli expressed these mRNA almost simultaneously, but a few cells demonstrated positive expression for only one of these probes. There was a parallel relationship between the degree of tissue damage and that of mRNA expressions of these probes in patients with IgAN, while patients with diabetic nephropathy showed a reverse relationship between these two parameters. It is concluded that patients with mesangial proliferative glomerulonephritis expressed mRNA for collagen collagenase and its inhibitor in the glomeruli in parallel with the progress of tissue damage. In contrast, glomerular samples from patients with diabetic nephropathy showed that there was an inverse relationship between tissue damage and expression of mRNA. It is concluded that expression of collagen, collagenase and its inhibitor parallels the progression of glomerular changes in IgAN, but such parallel expression was not observed in patients with diabetic nephropathy.  相似文献   
2.
We have studied the effects of hydrocortisone and adrenalineon natural killer (NK) cell activity and on the distributionof circulating lymphocyte sub-populations in 30 patients undergoingelective partial laminectomy under general anaesthesia. Thepatients were allocated to receive adrenaline (group 1, n =11), hydrocortisone and adrenaline (group 2, n = 11) or neitherhydrocortisone nor adrenaline (group 3, n = 8). Group 1 andgroup 2 patients received local adrenaline infiltration duringoperation to reduce bleeding. The mean dose of adrenaline administeredwas 2.1 (SD 0.2) µg kg–1 Group 2 received hydrocortisone10 mg kg–1 i.v. after premedication. In groups 1 and 2,adrenaline produced an instantaneous increase in NK cell activityaccompanied by a selective increase in circulating NK cells.The measurements returned to pre-infiltration levels within120 min of administration of adrenaline. The effect of adrenalinein causing increased NK cell activity was not blocked by pre-administrationof hydrocortisone. There was a significant decrease in the ratioof T helper/inducer cells (CD4) to T-suppressor/ cytotoxic cells(CD8) in all patients after induction of anaesthesia. In groups1 and 3, the CD4/CD8 cell ratio did not change significantlyduring operation. However, compared with groups 1 and 3, group2 showed a significantly reduced CD4/CD8 cell ratio during operation.Therefore, these results suggest that even in cases of suchsevere stress that the immune response was depressed by increasedserum cortisol concentrations, adrenaline-induced NK cell activityenhancement was preserved.  相似文献   
3.
Abstract— Effects of β-amyrin palmitate isolated from the leaves of Lobelia inflata were studied on the central nervous system of mice and were compared with those of antidepressant drugs, mianserin and imipramine. In the forced swimming test, β-amyrin palmitate, like mianserin and imipramine, reduced the duration of immobility of mice significantly in a dose-dependent manner (5, 10 and 20 mg kg?1). β-Amyrin palmitate (5, 10 and 20 mg kg?1) or mianserin (5, 10 and 20 mg kg?1) elicited a dose-related reduction in locomotor activity of mice and antagonized locomotor stimulation induced by methamphetamine. In contrast, imipramine (5, 10 and 20 mg kg?1) increased locomotor activity and potentiated methamphet-amine-induced hyperactivity. β-Amyrin palmitate showed no effect on reserpine-induced hypothermia, whilst mianserin (10 mg kg?1) and imipramine (10 and 20 mg kg?1) antagonized the reserpine-induced effect. Unlike imipramine, β-amyrin palmitate and mianserin did not affect haloperidol-induced catalepsy, tetrabenazine-induced ptosis and apomorphine-induced stereotypy. β-Amyrin palmitate and imipramine had no effects on the head-twitch response induced by 5-hydroxytryptophan, whereas mianserin (5, 10 and 20 mg kg?1) decreased it in a dose-dependent manner. A potentiating effect of β-amyrin palmitate (5, 10 and 20 mg kg?1) on narcosis induced by sodium pentobarbitone was stronger than that of imipramine (10, 20 and 40 mg kg?1) but weaker than that of mianserin (2·5, 5 and 10 mg kg?1). These results suggest that β-amyrin palmitate has similar properties in some respects to mianserin and might possess a sedative action. We suggest that β-amyrin palmitate has antidepressant activity with a mianserin-like profile of action.  相似文献   
4.
The importance of oxygen in maintaining the functional integrity of hepatocytes has been well established in a variety of experimental models, such as in vivo , perfused liver and isolated hepatocytes. However, one of the shortcomings of these systems is their short life span. Therefore, we have examined the effects of long-term hypoxia on cellular adenine nucleotide content and cellular functions, such as albumin production, urea production and DNA synthesis, in adult rat hepatocytes in primary culture. Hepatocytes were cultured at a density of 11 × 104 and 5 × 104 cells/0.18 mL per cm2 for the study of albumin and urea production and DNA synthesis, respectively, at various oxygen tensions (20, 12, 8 and 5%) for 24 h. Cellular ATP content in cultured hepatocytes in hypoxia gradually declined, corresponding to the decrease in oxygen tension, and the cellular ATP level at 5% oxygen was approximately 20% of that at 20% oxygen. Albumin production also decreased in parallel with the decrease in cellular ATP content in cultured hepatocytes in hypoxia. However, even when cellular ATP content gradually declined corresponding with the decrease in oxygen tension in cultured hepatocytes in hypoxia, such as at 8 or 5% oxygen, urea production remained at a high level; in contrast, DNA synthesis was completely suppressed. These results suggest that the cellular ATP content decreases in cultured hepatocytes during long-term hypoxia in relation to oxygen tension and that the relationship between decreased ATP levels and liver function in cultured hepatocytes during hypoxia differs for albumin production, urea production and DNA synthesis.  相似文献   
5.
The vacuolating cytotoxin and urease secreted by Helicobacter pylori are thought to be virulent factors. Because vacuolation is potentiated by the presence of ammonium ion, which is produced by urease in vitro, it is of interest to examine whether cytotoxin and urease work reciprocally in the development of atrophic gastritis or duodenal ulcer. In the present study, patients (all H. pyloripositive) were divided into four groups: mild atrophic gastritis (group 1; nine patients), severe atrophic gastritis (group 2; 36 patients), duodenal ulcer with mild atrophic gastritis (group 3; 19 patients) and duodenal ulcer with severe atrophic gastritis (group 4; 12 patients). Cytotoxin production and urease activity of H. pylori isolated from these patients were analysed. Cytotoxin production was observed in four of nine (44.4%), 28 of 36 (77.8%), 11 of 19 (57.9%) and eight of 12 (66.7%) isolates from groups 1, 2, 3 and 4, respectively. Cytotoxin-producing H. pylori isolates were found significantly more in patients with severe atrophy than in patients with mild atrophy (P= 0.048). The mean of relative activity of cytotoxin in H. pylori isolate was 1. 6. ± 2. 3, 7. 9. ± 7. 4, 5. 8. ± 6. 0 and 9. 0 ± 9. 1 in groups 1, 2, 3 and 4, respectively. Helicobacter pylori isolates from severe atrophy or duodenal ulcer patients in groups 2 or 4 possessed significantly higher activity than those from non-ulcer patients in group 1 (P= 0.017 and 0.030, respectively). The mean of urease activity was 8. 6 ± 4. 6, 10. 0 ± 5. 9, 10. 0 ± 8. 5 and 11. 2 ± 7. 7 IU/mg in groups 1, 2, 3 and 4, respectively. These differences indicated no statistical significance. In each H. pylori isolate, the production of cytotoxin and urease were independent, which indicated that there was no reciprocal effect between them in vivo. Thus, cytotoxin-producing H. pylori isolates were more prevalent in patients with severe atrophic gastritis and the cytotoxin activities of H. pylori isolates from the patients with severe atrophic gastritis or duodenal ulcer were much higher than those from the patients with mild atrophic gastritis, which suggested that vacuolating cytotoxin may be a disease-inducing factor.  相似文献   
6.
For providing costimulatory signals, we utilized anti-CD28 monoclonal antibody (mAb) for the in vitro culture of tumour-draining lymph node (LN) cells. The proliferation of B16 melanoma-draining LN cells in the culture with anti-CD3 mAb was remarkably enhanced by the addition of anti-CD28 mAb. In culture with both anti-CD3 and anti-CD28 mAb, the B16-draining LN cells produced a higher level of interferon-γ, but not interleukin-4, than with anti-CD3 mAb alone. The B16-draining LN cells efficiently expanded in the culture with both anti-CD3 and anti-CD28 mAb and subsequently with a low dose of IL-2 (anti-CD3 plus anti-CD28/IL-2). The expanded cells consisted predominantly of CD8+ T cells and showed a specific cytolytic activity, in a major histocompatibility complex (MHC) class I-restricted manner, even without in vitro restimulation. In addition, the adoptive transfer of the B16-draining LN cells, expanded in the culture protocol of anti-CD3 plus anti-CD28/IL-2, showed a significant anti-tumour effect against metastatic B16 melanoma in combination with IL-2. The cured mice thus acquired a specific protective immunity. Moreover, this protocol was also moderately effective against poorly immunogenic 3LL carcinoma. Overall, our results suggest the potential for another immunotherapeutic strategy based on ‘the costimulatory theory’ other than vaccination with B7-transfected tumour cells.  相似文献   
7.
Two hundred unrelated Japanese individuals were HL-A typed with UCLA Research Tray T3 (Terasaki's Tray), which contains specificities added after the Fifth International Workshop. Phenotype, gene and haplotype frequencies were calculated with standard errors and delta values. HL-A9, HL-A5 and W10 had a higher frequency and HL-A1, 3 and 8 had a lower frequency in Japanese than in Caucasians. The frequent haplotypes were HL-A9-HL-A5, HL-A9-HL-A7 and HL-A2W10. HL-A9-HL-A5 showed very positive high linkage disequilibrium parameter (delta value) and HL-A9-W10 showed negative high value. The sera designated as anti-HL-A, W5 and W15 in the T3 Tray which react identically in Caucasians showed different patterns of reaction when tested in the Japanese population. Five hundred Japanese parous women's sera were tested for cytotoxic antibodies. Some Japanese antisera showed high correlation coefficient values on HL-A2, HL-A9, HL-A10, HL-A11 and HL-A12. The women providing the anti-HL-5 complex sera and their immunizing persons were HL-A typed. These complex sera reactions were compared with the antisera in the T3 Tray. A new group of sera (SN-1), "operationally monospecific" and cross-reacting with W22, was found in the present study. Population and family studies suggested that the sera SN-1 are third in frequency within the second series (phenotypic frequency 17-22%) and show high delta values with HL-A11 in the Japanese population.  相似文献   
8.
Differences in the Mode of Lethality Produced through Intravenousand Oral Administration of Organophosphorus Insecticides inRats. TAKAHASHI, H., KOJIMA, T., IKEDA, T., TSUDA, S. and SHIRASU,Y. (1991). Fundam. Appl. Toxicol. 16, 459–468. This studywas undertaken to investigate the possibility that mechanismsother than cholinesterase (ChE) inhibition account for the acutetoxicity of organophosphorus insecticide. Both the PO type insecticide(direct ChE inhibitors: chlorfenvinphos and dichlorvos) andthe PS type insecticide (indirect ChE inhibitors: diazinon andfenthion) were employed. Rats treated with lethal doses of intravenousand oral PO type insecticides and oral PS type insecticidesexhibited typical signs of anti-ChE poisoning along with markedinhibition of brain and erythrocyte ChE activity. In contrast,rats given lethal doses of intravenous PS type insecticidesexhibited tonic convulsions and opisthotonos, with only slightinhibition of ChE activities. When PO type insecticides wereintravenously administered to anesthetized and conscious rats,animals exhibited typical anti-ChE poisoning signs in cardiorespiration:hypertension and apnea which were antagonized by atropine. Afteradministration of lethal doses of PO type insecticides, breathingdisappeared before the cessation of heart beats. Rats receivinglethal doses of intravenous PS type insecticides did not showhypertension, but exhibited transient cessation of breathingand heart beats. Breathing was observed after the disappearanceof heart beats. The electroencephalogram (EEG) was characterizedby spike and wave complexes. The EEG and cardiorespiratory changeswere not antagonized by atropine. It was concluded that lethalityfollowing intravenous PS type insecticides may be independentof ChE inhibition.  相似文献   
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