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51.
Phosphorylation of Rab proteins from the brain of Bombyx mori   总被引:1,自引:0,他引:1  
Rab proteins play fundamental roles in the regulation of membrane traffic. Previously, from the brain of Bombyx mori we isolated two cDNA clones (BRab1 and BRab14), each of which encoded a different member of Rab-protein family and was expressed in Escherichia coli and purified using an affinity chromatography. In this study, one cDNA clone (BRab8) was isolated from a cDNA library from the brain of B. mori. The recombinant protein was expressed in E. coli and purified. Next, the phosphorylations of these three purified BRab proteins were examined, using mammalian protein kinases in vitro. Protein kinase C (PKC) phosphorylated BRab8 and BRab14 proteins. Protein kinase A faintly phosphorylated BRab8 and BRab14 proteins. Calcium/calmodulin-dependent protein kinase faintly phosphorylated BRab8 protein. Next, brains of B. mori were dissected and homogenized. The homogenate showed a calcium-dependent protein kinase activity of BRab8 and BRab14 proteins. So PKC from the brain of B. mori was partially purified by a sequence of chromatographies on DEAE-Cellulofine and affinity chromatography. This PKC phosphorylated BRab8 and BRab14 proteins. These results suggest that the function of Rab proteins in the brain of B. mori is regulated by calcium-dependent protein kinases.  相似文献   
52.
Carotenoid synthesis during the past ∼30 years is summarized. Total syntheses of peridinin, fucoxanthin and halocynthiaxanthin, and biomimetic total syntheses of mytiloxanthin, crassostreaxanthin B, capsanthin, capsorubin, cucurbitaxanthin A, cycloviolaxanthin and capsanthin 3,6-epoxide are discussed.  相似文献   
53.
Gamblea innovans is a Cd- and Zn-accumulating deciduous tree widely distributed in the secondary forests of Japan. We aimed to understand the characteristics of Cd and Zn accumulation in G. innovans in order to effectively utilize the species for phytoremediation. To accomplish that, we studied the relationship between secondary metabolite concentrations and the accumulation and distributions of Cd and Zn in G. innovans leaves and basal stems using micro-X ray fluorescence (µ-XRF). Our results showed a negative correlation between Zn leaf concentrations and polyphenol/2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. This finding might be related to stress or the manifestation of a mechanism for tolerance to Cd and Zn accumulation. In addition, we observed that Cd accumulated primarily in the apoplastic region of surface tissues such as bark and the epidermis of leaves, whereas Zn accumulated in both apoplastic and symplastic regions. Thus, it might be possible that G. innovans can distinguish between Cd and Zn and control their translocation.  相似文献   
54.
Adipocyte size is closely related to the occurrence of diabetes, metabolic syndrome, and insulin resistance. Thus, researchers are searching for active substances that function to reduce adipocyte size. In the present study, we focused on sugar cane vinegar, Kibizu, and evaluated the function of Kibizu to reduce adipocyte size by using an in vitro model system, because people in Amami Oshima famous for longevity regularly consume Kibizu. Results showed that Kibizu treatment significantly reduced the size and number of lipid droplets in 3T3-L1 cells, relative to treatment with Kurozu, another traditional vinegar. Results of an extraction experiment suggest that the active components in Kibizu are lipophilic and hydrophobic. In addition, an in vivo experiment on rats treated with Kibizu showed that the active components were contained in large vein blood. Results of an additional in vivo experiment suggest that metabolites generated by Kibizu-treated rats are primarily contained or modified specifically in the large vein blood.  相似文献   
55.
Carboranes are a class of carbon-containing polyhedral boron-cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors. Estrogen deficiency results in marked bone loss due to increased osteoclastic bone resorption in females, but estrogen replacement therapy is not generally used for postmenopausal osteoporosis due to the risk of uterine cancer. We synthesized a novel carborane compound BE360 to clarify its anti-osteoporosis activity. BE360 showed a high binding affinity to estrogen receptors (ER), ERα and ERβ. In ovariectomized (OVX) mice, femoral bone volume was markedly reduced and BE360 dose-dependently restored bone loss in OVX mice. However, BE360 did not exhibit any estrogenic activity in the uterus. BE360 also restored bone loss in orchidectomized mice without androgenic action in the sex organs. Therefore, BE360 is a novel selective estrogen receptor modulator (SERM) that may offer a new therapy option for osteoporosis.  相似文献   
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57.
Delphinidin is an anthocyanidin commonly found in various fruits and vegetables. Delphinidin has been known to possess many functions, such as an antioxidant, and anti-inflammatory, anti-cancer and anti-muscular atrophy agent. In this study, we attempted to evaluate the effects of delphinidin on lipid accumulation in hepatocytes. The results showed that palmitic acid (PA)-induced cellular senescence in HepG2 cells and reduced the expression of SMARCD1, which is known to regulate senescence-associated lipid accumulation in hepatocytes. However, delphinidin-3-glucoside (D3 g) suppressed PA-induced senescence and reversed the expression of SMARCD1 to the level of untreated HepG2 cells. Consequently, D3 g inhibited PA-induced lipid accumulation through the restoration of the expression of SMARCD1 and fatty acid oxidation genes. Taken together, our results suggest that D3 g suppresses the lipid accumulation induced by hepatocyte senescence.  相似文献   
58.
Transplant and common garden experiments have been used in studies on local adaptation, but are difficult to be conducted for large animals with long life span. A previous study on the southern Japanese islands demonstrated that relative limb lengths of sika deer (Cervus nippon) were short on islands with steep slopes. We hypothesized that this morphological variation was evidence for local adaptation, and tested this hypothesis by comparing phenotypic divergence with neutral genetic divergence among eight populations of the sika deer in the southern Japanese islands. Divergence patterns differed between the phenotypic and neutral genetic features. Genetic similarity was high among individuals on Kyushu (OI, KGS, and KGK). Individuals on Tanegashima (TN) and Yakushima (YK) also constituted a group, whereas individuals on Tsushima (TS), Wakamatsujima (WM), and Kuchinoerabujima (KE) formed a genetically distinct group. Phenotypic data indicated that individuals from TS, OI, KGS, and KGK exhibited similarity, whereas individuals on YK formed an isolated group that was separated from the other populations. The degree of phenotypic divergence was larger than that of neutral genetic divergence between TN and YK. These results suggest that divergent selection worked between two of the eight island populations (TN and YK). The morphological trait of captive-bred individuals from TN and YK, which had never experienced their original environments, retained their original morphological features. By combining the results of multiple analyses, we found that the difference in relative limb length between the two populations was consistent with local adaptation hypothesis, although conclusive results were not obtained for the other populations.  相似文献   
59.

Background

There are no studies about the caregiving burdens in families of patients with eating disorders in Japan, and only limited studies on the role of caregivers’ stress coping, social support, and mental health. This study examines caregiving burdens, mental health conditions, and associated factors in caregivers of anorexia nervosa (AN) patients in Japan.

Methods

Seventy-nine principal caregivers (70 mothers, 5 fathers, 3 spouses and 1 grandmother; mean age 56.0?±?8.0 years) for outpatients with AN (all female; mean age 26.6?±?7.9 years; BMI 14.6?±?3.2 kg/m2) were evaluated using self-report questionnaires in a cross-sectional study. The questionnaires included caregiving burden (J-ZBI_8), mental health conditions (GHQ28), stress coping styles (CISS), social support (SNQ), severity of the patient’s symptoms from the family’s perspective (ABOS), and family functioning (GF-FAD). Clinical information about the patients was also obtained.

Results

Mean caregiving burden assessed by J-ZBI_8 score was 12.4?±?7.0 (SD). The total GHQ score was 31.6?±?13.7 (Likert scoring) and 9.2?±?7.0 (GHQ scoring). Of the respondents, 48 (60.7 %) indicated a high risk for mental health problems that exceeded the cutoff point of the GHQ. Significantly higher caregiving burden and poor mental health conditions were shown in the group who had contact with patients?>?6 h a day compared to the group with daily patient contact?<?3 h (F (2, 76)?=?3.19, p?=?0.047 and F (2, 76)?=?9.39, p?<?0.001, respectively). Stepwise multiple regression analysis indicated that the factors that significantly predicted the caregiving burden were severity of the patient’s symptoms from the family’s perspective (β?=?0.47, p?<?0.001) and Emotion-Oriented Coping (β?=?0.38, p?=?0.002) (R2?=?0.401), while predictors of mental health conditions were Emotion-Oriented Coping (β?=?0.522, p?<?0.001), Affective Support (β?=??0.419, p?<?0.001), and contact time with patient (β?=?0.201, p?=?0.042) (R2?=?0.602).

Conclusion

Caregivers of AN patients experienced heavy burdens and manifested poor mental health conditions. The severity of the patient’s symptoms from the family’s perspective and the greater use of emotion-oriented coping were associated with higher burdens. Greater use of emotion-oriented coping, less affective support and longer contact with patients were related to worse mental health conditions. Interventions to promote caregivers’ adaptive coping styles may help reduce their caregiving burden and improve their mental health.
  相似文献   
60.
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