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1.
Human and nonhuman primates comprehend the actions of other individuals by detecting social cues, including others’ goal-directed motor actions and faces. However, little is known about how this information is integrated with action understanding. Here, we present the ontogenetic and evolutionary foundations of this capacity by comparing face-scanning patterns of chimpanzees and humans as they viewed goal-directed human actions within contexts that differ in whether or not the predicted goal is achieved. Human adults and children attend to the actor’s face during action sequences, and this tendency is particularly pronounced in adults when observing that the predicted goal is not achieved. Chimpanzees rarely attend to the actor’s face during the goal-directed action, regardless of whether the predicted action goal is achieved or not. These results suggest that in humans, but not chimpanzees, attention to actor’s faces conveying referential information toward the target object indicates the process of observers making inferences about the intentionality of an action. Furthermore, this remarkable predisposition to observe others’ actions by integrating the prediction of action goals and the actor’s intention is developmentally acquired.  相似文献   
2.
We studied the ultrastructural distribution of fibronectin in the smooth muscle layer of mouse small intestine with affinity-purified antibodies using the immunogold technique. Fibronectin was present over the pericellular area extending from the cell membrane to the extracellular matrix beyond the basal lamina. Distribution of the glycoprotein over the pericellular area was heterogeneous, i.e., it was localized more abundantly in the narrow space between smooth muscle cells, the gaps having a width of 60-80 nm where the two dense bands in adjacent cells matched each other. Such localization suggests that fibronectin contributes to cell adhesion. Within the basement membrane, gold label was localized both in lamina lucida and lamina densa, more densely in the latter than in the former. Fibronectin was also co-distributed with collagen fibers in the extracellular matrix. Within smooth muscle cells, gold particles were observed on rough endoplasmic reticulum and secretory vesicle-like structures. These results suggest that smooth muscle cells synthesize fibronectin and secrete it as a component of the basal lamina and extracellular matrix.  相似文献   
3.
The blood clamBarbatia virescens has a heterodimeric hemoglobin in erythrocytes. Interestingly, the congeneric clamsB. reeveana andB. lima contain quite different hemoglobins: tetramer and polymeric hemoglobin consisting of unusual didomain chain. The complete amino acid sequence of chain I ofB. virescens has been determined. The sequence was mainly determined from CNBr peptides and their subpeptides, and the alignment of the peptides was confirmed by sequencing of PCR-amplified cDNA forB. virescens chain I. The cDNA-derived amino acid sequence matched completely with the sequence proposed from protein sequencing.B. virescens chain I is composed of 156 amino acid residues, and the molecular mass was calculated to be 18,387 D, including a heme group. The sequence ofB. virescens chain I showed 35–42% sequence identity with those of the related clamAnadara trapezia and the congeneric clamB. reeveana. An evolutionary tree forAnadara andBarbatia chains clearly indicates that all of the chains are evolved from one ancestral globin gene, and that the divergence of chains has occurred in each clam after the speciation. The evolutionary rate for clam hemoglobins was estimated to be about four times faster than that of vertebrate hemoglobin. We suggest that blood clam hemoglobin is a physiologically less important molecule when compared with vertebrate hemoglobins, and so it evolved rapidly and resulted in a remarkable diversity in quaternary and subunit structure within a relatively short period.  相似文献   
4.
Summary In order to examine the intracellular distribution of precursors of type I and type III collagen and fibronectin in the palatal mesenchymal (MEPM) cells of the mouse embryo cultured under ascorbate-deficient conditions, immuno-electron-microscopic studies were carried out by use of affinity purified antibodies for these proteins. MEPM cells were obtained from the palatal shelves of 14-day-old mouse fetuses and cultured for 3–7 days in medium, either with or without 50 ng/dish/day ascorbic acid. Results obtained were as follows: (1) Although the rough endoplasmic reticulum (rER) of MEPM cells cultured for 5 days in ascorbate-supplemented medium was flattened, that in cells cultured in ascorbate-deficient medium had a distended or vesicular appearance. (2) Vesicular or distended rER showed heterogeneous staining for both type I and type III collagen, namely, some parts of rER showed positive staining for both types of collagen, while others showed negative staining. (3) Both type I and type III collagen showed codistribution in the same vesicular rER. (4) Vesicular rER showed negative or very faint labelling for fibronectin. These results may suggest regional differences in the function of rER.  相似文献   
5.
An 8-year-old girl with meningococcal meningitis lacked serum complement activity. The seventh component of complement (C7) could not be detected in her serum by either functional or immunochemical analysis. The levels of the other components were within the normal range. Her serum complement activity was restored by the addition of purified C7. Her fresh serum showed a total absence of bactericidal activity against Neisseria meningitidis, group Y, but her serum bactericidal activity was restored by the addition of purified C7. The restoration of her serum bactericidal activity was completely inhibited in the presence of Mg2+ EGTA. These findings suggest that restoration of the bactericidal activity of her serum against N. meningitidis might be mediated by the specific antibody against N. meningitidis and the reconstituted complement system in her serum. Heterozygous deficiency of C7 was found in 10 of her family members. Genetic studies showed that the mode of inheritance might be an autosomal codominant trait. No genetic linkage between deficiency of C7 and the HLA system was found.  相似文献   
6.
Larvae of the rice stem borer utilize simple carbohydrates and protein in their food at rates as high as most other lepidopterous larvae. The larvae also utilize starch at an unexpectedly high rate, in view of early evidences that the starch-hydrolyzing enzyme of the larval digestive tract is very weak and that the nutritive value of starch in synthetic food is very low. The results indicate that starch contained in the rice stem may be significant in the nutrition of the larvae in the field.
Zusammenfassung Die Larven von Chilo suppressalis Walker verwerten einfache Kohlehydrate und Proteine ihrer Nahrung in ebenso hohem Ausmaße wie die meisten anderen phytophagen Lepidopteren-larven. Jedoch nutzen die Raupen auch Stärke in einem unerwartet hohen Maße aus; unerwartet in Anbetracht der früheren Befunde, wonach das stärkehydrolysierende Ferment des larvalen Verdauungskanals schwach und der Nährwert von Stärke bei synthetischer Ernährung sehr niedrig ist. Die Ergebnisse weisen darauf hin, daß die im Reisstengel enthaltene Stärke für die Ernährung der Larven bedeutsam sein kann.
  相似文献   
7.
8.
The influence of equilibration time before vitrification on the viability of vitrified morula- to blastocyst-stage bovine embryos and in vivo viability of vitrified embryos following transfer to recipients were investigated. In experiment 1, the embryos were exposed to an equilibration solution (50% VSED) containing 12.5% v/v ethylene glycol and 12.5% v/v dimethyl sulfoxide in modified Dulbecco's phosphate buffered saline with 4 mg/ml BSA (m-PBS) for 1, 2 and 5 minutes at room temperature (22 to 24 degrees C). The embryos were then placed in 15mul vitrification solution (VSED) consisting of 25% v/v ethylene glycol and 25% v/v dimethyl sulfoxide in m-PBS and were loaded into 0.25 ml plastic straws at room temperature. After 30 seconds, the straws were placed in liquid nitrogen (LN(2)) vapor for 2 minutes, plunged and stored in LN(2). To thaw, the straws were warmed in water at 20 degrees C for 15 seconds and the contents of the straws were expelled into a plastic dish. The embryos were diluted in 0.5 M sucrose + m-PBS for 5 minutes and were cultured in TCM-199 supplemented with bovine oviductal epithelial tissue. Viability of the embryos was assessed by the forming or reforming of the blastocoele after 24 hours of culture. High in vitro survival rates (73 approximately 90%) of vitrified embryos were obtained after 1 and 2 minute equilibrations, but was reduced (P<0.05) after 5 minute equilibration. In Experiment 2, morula- to blastocyst-stage embryos were vitrified after 1 minute equilibration in 50% VSED and 30 seconds of exposure to VSED. The vitrified-warmed embryos were transferred to recipient heifers at 7 days after estrus (1 embryo per recipient). Five (38%) of 13 (40%) of 10 recipients that had received blastocysts were diagnosed as pregnant using ultrasonography 60 days following transfer.  相似文献   
9.
When eight cultivars of Capsicum annuum were used as female parents in interspecific crosses with two accessions of C. chinense, dwarfism occurred in hybrids originating from 10 out of 16 combinations, while hybrids of the remaining 6 combinations grew normally. In contrast, when C. chinense was used as female parent, all of the hybrids showed severely stunted growth as if affected by a virus. These results suggested that the stunted growth expressed in the cross of C. chinense x C. annuum is caused by an interaction between nuclear gene(s) from C. annuum and the cytoplasm of C. chinense. To examine the number of nuclear gene(s) which cause(s) the stunted growth, we backcrossed F1 hybrids of C. annuum x C. chinense to C. chinense. About one-quarter of the progeny in the backcrossed hybrids of C. chinense x (C. annuum x C. chinense) showed the same stunted growth shown by the f1 hybrids of C. chinense x C. annuum, suggesting that two complementary genes of C. annuum cause the stunted growth. However, the higher abortion rates of ovules and lower germination percentage of seeds in C. chinense x C. annuum than in the selfed C. chinense implied that the genetic ratio of the stunted type would have been higher than that observed in the C. chinense x (C. annuum x C. chinense) progeny. We then attempted a linkage analysis between the stunted growth and randomly amplified polymorphic DNA (RAPD) of C. chinense x (C. annuum x C. chinense) progeny. A RAPD marker that associated with 94% of the stunted plants but not with 94% of the normal one was identified. This confirmed that a single nuclear gene of C. annuum which is linked to the RAPD marker with a recombination value of 6% causes the stunted growth in an interaction with the cytoplasm of C. chinense.  相似文献   
10.
M Nakamura  S Ohnishi  H Kitamura  S Inai 《Biochemistry》1976,15(22):4838-4843
The structural change in erythrocyte membranes induced by antibody and complement was studied using phospholipid spin-labels. Sheep erythrocytes were labeled with phosphatidylcholine spin-label and various intermediate cells (erythrocyte-antibody complex (EA), EA bound with complement components from C1 to C7 (EAC1-7), EAC1-8, and EAC1-9) were prepared. Electron spin resonance spectra of EA, EAC1-7, and EAC1-8 were very similar to that of the erythrocytes, while that of EAC1-9 was markedly different. The overall splitting value for the lysed EAC1-9 (53 G) was much smaller than that for the erythrocytes (57 G), indicating a marked fluidization around the phosphatidylcholine label. The unlysed EAC1-9 membranes contained a limited fraction of the fluidized area. When EA was reacted with complement in the presence of 36% bovine serum albumin, the membranes were fluidized similarly to the lysed EAC1-9, although the hemolysis was largely blocked. The membranes of unlysed EAC1-9 prepared in isotonic (ethylenedinitrilo)tetraacetic acid were also fluidized, but to somewhat smaller extent. The role of C9 in the modification of erythrocyte membranes was also demonstrated using Mg2+ ghosts, which were prepared by hypotonic hemolysis in the presence of Mg2+. The membranes of Mg2+ ghost of EAC1-7 were markedly fluidized when bound with C8 and C9, but not affected by binding of C8 only. The component C8 was found to give a latent effect on the membranes that caused irreversible fluidization upon osmotic shock. The terminal component thus creates a fluidized area in the erythrocyte membranes through which small ions and molecules may diffuse more easily and the resulting osmotic unbalance may finally cause hemolysis.  相似文献   
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