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1.
Abstract — The concentrations of IgA, lysozyme and β-microglobulin (β2-m) were quantitated in wax-stimulated mixed saliva from 28 patients with severe periodontitis and from 28 healthy controls. The mutual correlations between IgA, lysozyme and β2-rn were determined. In patients with periodontitis decreased lysozyme concentrations were detected when compared with controls (P<0.05). The correlation between IgA and β2-m concentrations was highly significant in both groups studied (P<0.0001, and P <0.002), whereas β2-m and lysozyme concentrations were positively correlated in patients but not in controls. In addition, a significant correlation between IgA and lysozyme was found only in periodontal patients ( P <0.001).  相似文献   
2.
Bone-marrow regeneration after chemo- and radiotherapy-induced aplasia can be monitored by serum levels of myeloperoxidase (MPO), lysozyme (LYS) and lactoferrin (LF). In 10 patients with leukemia, serum measurements were performed before and after bone-marrow transplantation. Bone-marrow regeneration was suggested by increments in serum MPO and LYS 5 and 4 days prior to the increase in mononuclear cells (Mono) and 10 and 9 d before the increase in polymorphonuclear leukocytes (PMN) in the peripheral blood. LF started to rise 4.5 d before detectable circulating PMNs. 2 patients with early relapses of leukemia post transplantation are shown to display atypical patterns of serum MPO and LYS. We conclude that serum measurements of MPO, LYS and LF may be used as early and sensitive means to monitor bone-marrow activity during hematological regeneration. However, the findings also strongly support the earlier proposal that MPO alone may be used to reflect myeloid activity in the bone-marrow in general.  相似文献   
3.
The effect of surface sugars of liposomes on the immunological responses to entrapped antigen has been investigated. alpha-Mannose and beta-galactose were grafted on the surface of liposomes containing lysozyme by covalent coupling of p-aminophenyl-D-glycosides to phosphatidyl ethanolamine liposomes using glutaraldehyde. Subcutaneous administration of antigen entrapped in beta-galactose liposomes stimulated an antibody response comparable to that elicited by sugar-free neutral liposomes. However, alpha-mannose bearing liposomes with entrapped lysozyme elicited an immune response similar to that induced by lysozyme in saline. Based on these observations it is suggested that alpha-mannose liposomes, that are specifically recognized by macrophages, are taken up rapidly by receptor mediated endocytosis and that the entrapped antigen is then rapidly degraded, resulting in low antibody production.  相似文献   
4.
The aggregation of non-serotypable Haemophilus influenzae (NTHI) by whole saliva from patients with chronic obstructive lung disease (COLD) was investigated. Significant differences were observed between salivary aggregating activity of a control and COLD population (P < 0.001). Saliva from patients less prone to acute exacerbations had a greater capacity to aggregate bacteria compared with saliva from patients with a predilection to infection. The mechanism of saliva-mediated aggregation of NTHI was investigated and shown to be related to lysozyme content. Lysozyme activity in saliva was measured by the turbidimetric technique and results showed that patients with chronic bronchitis had increased levels of salivary lysozyme, with a subpopulation within the non-infection-prone group having greater amounts. A significant difference was observed in salivary lysozyme between controls and non-infection-prone (P < 0.005) and infection-prone (P < 0.05) patients, respectively: the non-infection-prone patients having significantly (P < 0.005) more than the infection-prone patients. There was significant correlation (r = 0.742, P < 0.001) between salivary aggregation of NTHI and lysozyme activity. Chromatographically purified human lysozyme had a similar aggregation profile to that of saliva. There was no difference in serum and saliva lactoferrin concentrations between groups, but there was a significant increase (P < 0.05) in serum lysozyme concentration in the non-infection-prone group. This study suggests that the level of salivary lysozyme derived from macrophages may play an important role in determining resistance or susceptibility to acute bronchitis.  相似文献   
5.
The effectiveness of lysosubtilin and lysozyme, a combination thereof and a combination of these enzyme preparations (each alone and in combination) with vitamins as possible coimmunostimulants, which reduced the milk somatic cell count (SCC), were compared in a field trial. Seventy second to third lactation Lithuanian Black and White cows with a similar milk SCC ([750±200]×103?cells?ml?1) and of a similar weight (550±50?kg) were involved in the trial and were randomly allocated into seven groups (n=10). Lysosubtilin and/or lysozyme at doses of 0.02?g?kg?wt?1 and 0.2?g?kg?wt?1, respectively, and vitamins A, C and E (if any) at doses twice as high as required for nutritional adequacy were given, except for control group cows, once daily with feed for ten successive days. After four-, seven-, and ten-day periods of giving enzymes (with or without vitamins) a significant reduction of SCC (p<0.001) was observed in the milk of cows that received a combination of lysozyme with vitamins. On the tenth day a significant reduction of SCC (p<0.001) was also observed in the milk of cows that received lysozyme and lysosubtilin (each alone; without vitamins) or lysosubtilin in combination with vitamins. At the end of the trial (on the 15th day) SCC in milk of cows of all of the study groups was significantly lower (p<0.001) when compared with that of the control group.  相似文献   
6.
Immunoglobulin-producing cells and epithelial expression of secretory component (SC), amylase, lysozyme (Ly) and lactoferrin (Lf) were studied by immunohistochemistry to obtain information about the development of mucosal immunity. Tissue specimens were obtained from 20 fetal and 40 postnatal parotid glands. (1) Fetal specimens. Occasional IgM- and IgA- but no IgD-, IgG- or IgE- producing cells were seen (ratios, IgM:IgA:IgD:IgG:IgE approximately 4:1:0:0:0). The IgAl subclass dominated (median 90%, range 50-95%) and these cells were mostly J-chain-positive (median 97%, range 94-98%). Only few IgA2-producing cells were seen (median 10%, range 5-50%) and they were also mostly J-chain-positive (median 99%, range 98-100%). Amylase, Ly and Lf were most prominent in early fetal life, while only small amounts of SC were present. (2) Postnatal specimens. Secretory component increased markedly along with a growing number of IgA- and IgD-producing cells (IgA:IgM:IgD:IgG:IgE approximately 4:2:1:1:0). The IgAl subclass remained predominant (median 65%, range 50-90%) although the proportion of IgA2-positive cells tended to be raised (median 35%, range 10-50%). Most IgAl (median 97%, range 67-100%) and IgA2 (median 94%, range 75-100%) cells were J-chain-positive. These features probably reflected local activation of the immune system in response to environmental factors. The amount of amylase, Ly and Lf decreased shortly after delivery, perhaps because the cellular stores were emptied by postnatal increase in secretory activity.  相似文献   
7.
The phagocytic activity of the leukocytes and the serum complement, properdin, and lysozyme levels were studied in germfree miniature piglets and similar animals ocntaiminated withEscherichia coli 055 andE. coli 083. In the presence of autologous serum and complement phagocytosis ofE. coli 055 cells was inhibited, but it was considerably intensified under the influence of specific opsonins (antibodies againstE. coli 055). Lowered levels of complement, properdin, and lysozyme were found in the germfree animals. After peroral monocontamination withE. coli the formation of properdin and complement was stimulated the most, and that of lysozyme the least. Antibodies againstE. coli 055 were not found in the monocontaminated piglets. The highest lysozyme levels were found in the previously germfree animals, which points to the role of other contamination factors thanE. coli cells in the stimulation of lysozyme. It is concluded that microbial contamination plays an important role in the development of the cellular and humoral factors of resistance.Research Laboratory of Experimental Biological Models, Academy of Sciences of the USSR, Moscow Region. (Presented by Academician of the Academy of Medical Sciences of the USSR, N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 86, No. 9, pp. 341–344, September, 1978.  相似文献   
8.
溶菌酶对酵母型真菌抗菌作用的实验观察   总被引:2,自引:1,他引:1  
目的:探讨溶菌酶抗真菌作用。方法:在涂布接种白色念珠菌,新生陷球菌的沙保琼脂平板滴加50-2000μg的溶菌酶,于37℃培养进行抑菌试验,在低倍显微镜下观察抑菌圈内实验菌的形态大小及细小菌落的形态特征,并涂片染色镜检,以加酶部位形成抑菌圈及抑菌圈内溶菌酶作用后的实验菌大小、形态结构及染色反应色镜检,以加酶部位形成抑菌圈及抑菌圈内溶菌酶作用后的实验菌大小、形态结构及染色反应判定溶菌酶的抗真菌作用。结  相似文献   
9.
  1. Studies were directed at determining whether hepatocytes, isolated from female Sprague-Dawley rats, facilitate the uptake of protein-bound long-chain fatty acids. We postulated one form of facilitated uptake may occur through an ionic interaction between the protein-ligand complex and the cell surface. These interactions are expected to supply additional ligand to the cell for uptake.
  2. The clearance rate of [3H]-palmitate in the presence of α1-acid-glycoprotein (pI=2.7), albumin (pI=4.9) and lysozyme (pI=11.0) was investigated. Palmitate uptake was determined in the presence of protein concentrations that resulted in similar unbound ligand fractions (=0.03). The experimental clearance rates were compared to the theoretical predictions based upon the diffusion-reaction model.
  3. By use of our experimentally determined equilibrium binding and dissociation rate constants for the various protein-palmitate complexes, the diffusion-reaction model predicted clearance rates were 4.9 μl s−1/106 cells, 4.8 μl s−1/106 cells and 5.5 μl s−1/106 cells for α1-acid-glycoprotein, albumin and lysozyme, respectively; whereas the measured hepatocyte palmitate clearance rates were 1.2±0.1 μl s−1/106 cells, 2.3±0.3 μl s−1/106 cells and 7.1±0.7 μl s−1/106, respectively.
  4. Hepatocyte palmitate clearance was significantly faster (P<0.01) in the presence of lysozyme than albumin which was significantly faster than α1-acid-glycoprotein (P<0.01). The marked difference in clearance rates could not be explained by considering differences in solution viscosity.
  5. Our results are consistent with the notion that ionic interactions between protein-ligand complexes and the cell surface facilitate the ligand uptake by decreasing the diffusional distance of the unbound ligand and/or by facilitating the protein-ligand dissociation rate.
  相似文献   
10.
喷雾干燥对溶菌酶一级结构的影响   总被引:1,自引:1,他引:1  
目的 考察喷雾干燥对溶茵酶一级结构稳定性的影响。方法 以送料速度2.4 ml/min、进口气流温度150℃、出口气流温度70℃、雾化器转速18 000 r/min制备喷雾干燥溶茵酶。采用MALDI-TOF/MS测定喷雾干燥对溶菌酶一级结构的影响。结果 喷雾干燥溶菌酶除了具有溶菌酶相同的准分子离子峰、二聚体、三聚体、四聚体及三聚体的两电荷离子峰外,另多5个碎片离子峰。结论 喷雾干燥可造成溶菌酶一级结构破坏。  相似文献   
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