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121.
Anthropologists have long been fascinated by the isolated hunter-gatherer populations in Southeast Asia (SEA) collectively known as "Negritos." However, the origins and affinities of these groups remain unresolved. Negritos are characterized by their short stature, dark skin color, and wiry hair, and they inhabit the Philippines, Malay Peninsula, and the Andaman Islands. Among Philippine Negritos, the Batak are of particular interest in understanding population interactions in the region due to their location on Palawan Island, which likely formed a corridor by which human migrations entered the rest of the Philippine archipelago from Island SEA. Here, we extend current understanding of the distribution of genetic diversity in Negritos by presenting the first analysis of mitochondrial DNA and Y-chromosome diversity among the Batak. We show that the Batak are genetically distinct from Negritos of the Andaman Islands and Malay Peninsula and instead bear most resemblance to geographically proximate Philippine Negritos and to non-Negrito populations from the Philippines and Island SEA. An extensive degree of recent admixture between the Batak and their neighbors is indicated by the high frequency of recently coalescing haplogroups in the Batak that are found throughout Island SEA. The comparison of results from these two loci further lends support to the hypothesis that male-biased admixture has, in particular, been a prominent feature of the interactions between the Batak and surrounding non-Negrito populations.  相似文献   
122.
The human papillomavirus (HPV) L2 capsid protein plays an essential role during the early stages of viral infection, but the molecular mechanisms underlying its mode of action remain obscure. Using a proteomic approach, we have identified the adaptor protein, sorting nexin 17 (SNX17) as a strong interacting partner of HPV L2. This interaction occurs through a highly conserved SNX17 consensus binding motif, which is present in the majority of HPV L2 proteins analysed. Using mutants of L2 defective for SNX17 interaction, or siRNA ablation of SNX17 expression, we demonstrate that the interaction between L2 and SNX17 is essential for viral infection. Furthermore, loss of the L2-SNX17 interaction results in enhanced turnover of the L2 protein and decreased stability of the viral capsids, and concomitantly, there is a dramatic decrease in the efficiency with which viral genomes transit to the nucleus. Indeed, using a range of endosomal and lysosomal markers, we show that capsids defective in their capacity to bind SNX17 transit much more rapidly to the lysosomal compartment. These results demonstrate that the L2-SNX17 interaction is essential for viral infection and facilitates the escape of the L2-DNA complex from the late endosomal/lysosomal compartments.  相似文献   
123.
Zinc oxide (ZnO) nanoparticles are one of the important industrial nanoparticles. The production of ZnO nanoparticles is increasing every year. On the other hand, it is known that ZnO nanoparticles have strong cytotoxicity. In vitro studies using culture cells revealed that ZnO nanoparticles induce severe oxidative stress. However, the in vivo influence of ZnO nanoparticles is still unclear. In the present study, rat lung was exposed to ZnO nanoparticles by intratracheal instillation, and the influences of ZnO nanoparticles to the lung in the acute phase, particularly oxidative stress, were examined. Additionally, in vitro cellular influences of ZnO nanoparticles were examined using lung carcinoma A549 cells and compared to in vivo examinations. The ZnO nanoparticles used in this study released zinc ion in both dispersions. In the in vivo examinations, ZnO dispersion induced strong oxidative stress in the lung in the acute phase. The oxidative stress induced by the ZnO nanoparticles was stronger than that of a ZnCl(2) solution. Intratracheal instillation of ZnO nanoparticles induced an increase of lipid peroxide, HO-1 and alpha-tocopherol in the lung. The ZnO nanoparticles also induced strong oxidative stress and cell death in culture cells. Intracellular zinc level and reactive oxygen species were increased. These results suggest that ZnO nanoparticles induce oxidative stress in the lung in the acute phase. Intracellular ROS level had a high correlation with intracellular Zn(2+) level. ZnO nanoparticles will stay in the lung and continually release zinc ion, and thus stronger oxidative stress is induced.  相似文献   
124.
BackgroundSurveillance systems are increasingly relying upon community-based or crowd-sourced data to complement traditional facilities-based data sources. Data collected by community health workers during the routine course of care could combine the early warning power of community-based data collection with the predictability and diagnostic regularity of facility data. These data could inform public health responses to epidemics and spatially-clustered endemic diseases. Here, we analyze data collected on a daily basis by community health workers during the routine course of clinical care in rural Nepal. We evaluate if such community-based surveillance systems can capture temporal trends in diarrheal diseases and acute respiratory infections.MethodsDuring the course of their clinical activities from January to December 2013, community health workers recorded healthcare encounters using mobile phones. In parallel, we accessed condition-specific admissions from 2011–2013 in the hospital from which the community health program was based. We compared diarrhea and acute respiratory infection rates from both the hospital and the community, and assigned three categories of local disease activity (low, medium, and high) to each week in each village cluster with categories determined by tertiles. We compared condition-specific mean hospital rates across categories using ANOVA to assess concordance between hospital and community-collected data.ResultsThere were 2,710 cases of diarrhea and 373 cases of acute respiratory infection reported by community health workers during the one-year study period. At the hospital, the average weekly incidence of diarrhea and acute respiratory infections over the three-year period was 1.8 and 3.9 cases respectively per 1,000 people in each village cluster. In the community, the average weekly rate of diarrhea and acute respiratory infections was 2.7 and 0.5 cases respectively per 1,000 people. Both diarrhea and acute respiratory infections exhibited significant differences between the three categories of disease rate burden (diarrhea p = 0.009, acute respiratory infection p = 0.001) when comparing community health worker-collected rates to hospital rates.ConclusionCommunity-level data on diarrhea and acute respiratory infections modestly correlated with hospital data for the same condition in each village each week. Our experience suggests that community health worker-collected data on mobile phones may be a feasible adjunct to other community- and healthcare-related data sources for surveillance of such conditions. Such systems are vitally needed in resource-limited settings like rural Nepal.  相似文献   
125.
126.
The voltage-gated sodium channel, Nav1.1, is predominantly expressed in parvalbumin-positive fast spiking interneurons and has been genetically linked to Dravet syndrome. Starting from a high throughput screening hit isoxazole derivative 5, modifications of 5 via combinations of IonWorks and Q-patch assays successfully identified the nicotinamide derivative 4. Its increasing decay time constant (tau) of Nav1.1 currents at 0.03?μM along with significant selectivity against Nav1.2, Nav1.5, and Nav1.6 and acceptable brain exposure in mice was observed. Compound 4 is a promising Nav1.1 activator that can be used to analyze pathophysiological functions of the Nav1.1 channel towards treating various central nervous system diseases.  相似文献   
127.
Usui R  Shibuya M  Ishibashi S  Maru Y 《EMBO reports》2007,8(12):1155-1161
Elevated serum low-density lipoprotein (LDL) is a risk factor for atherosclerotic disorders. However, prominent atherosclerosis, which has been observed in LDL receptor (LDLR)-knockout mice, has diminished the significance of LDLR as a cause of atherosclerosis, while elaborate studies have focused on the receptors for denatured LDL. Here we report that native LDL (nLDL) activates vascular endothelial growth factor (VEGF) receptor 1 (VEGFR1) but not VEGFR2 through LDLR and is as potent as VEGF in macrophage migration. Binding and co-endocytosis of VEGFR1 and LDLR were enhanced by nLDL, which is concomitant with ubiquitination-mediated degradation of VEGFR1. We propose that LDLR-mediated use of VEGFR1 by nLDL could be a potential therapeutic target in atherosclerotic disorders.  相似文献   
128.
129.
The objectives of this study were to evaluate outcomes of a comprehensive care clinic (CCC) for children with hypothalamic obesity due to treatment for brain tumors by assessing weight parameters; health‐related quality of life (HRQoL); and perception of health status, disease burden, care satisfaction, and physical activity. Thirty‐nine patients (16 males) were reviewed. While attending the CCC the median %weight gain and percent ideal body weight (%IBW) of patients was lower (8.5%/year (range ?3 to ?14) and ?4%/year (141.7–34), respectively) than the median %weight gain and %IBW (21.4% (15.8?32.0) and 19.9% (?18.7 to 149.2)) while treated in standard care. Rate of increase in %BMI slowed (4.5 kg/m2 %/year (?17.8 to 8.4) vs. 8.4 kg/m2 %/year (?3.1 to 28.1)) in patients attending the clinic compared to their before treatment in standard care. There was no change in blood pressure, fasting glucose, triglycerides or low‐density lipoprotein cholesterol, and a significant increase in high‐density lipoprotein cholesterol (1.09 ± 0.33 to 1.24 ± 0.04). After attending the CCC for a year, significant increases for child reported total HRQoL (63.7 ± 18.4–71.3 ± 13.3; P < 0.017), physical functioning (65.3 ± 15.9–69.5 ± 15.9; P < 0.045) and school functioning (61.1 ± 21.0–71.1 ± 16.5; P < 0.051) were found. Parents reported no significant change in HRQoL over the same period. Parents had significantly improved responses in areas of coordination of health care and understanding of their child's disease. Patients attending the CCC gained less weight while attending the clinic and exhibited improved HRQoL. Parents noticed improvements in various areas of their child's medical care.  相似文献   
130.
Twenty-nine randomly chosen, soluble antigens, many of them highly complex, were used to immunize mice of two strains, C3H and B10.RIII. Lymphnode cells from the immunized mice were restimulated in vitro with the priming antigens and the proliferative response of the cells was determined. Both strains were responders to 28 of 29 antigens. Eight antigens were then used to immunize 11 congenic strains carrying different H-2 haplotypes, and the T-cell proliferative responses of these strains were determined. Again, all the strains responded to seven of the eight antigens. These experiments were then repeated, but this time -antibodies specific for the A (AA) or E (EE) molecules were added to the culture to block the in vitro responsiveness. In all but one of the responses, inhibition with both A-specific and E-specific antibodies was observed. The response to one antigen (Blastoinyces) was exceptional in that some strains were nonresponders to this antigen. Furthermore, the response in the responder strains was blocked with A-specific, but not with E-specific, antibodies. The study demonstrates that responses to antigens not controlled by Irr genes nevertheless require participation of class II Mhc molecules. In contrast to Ir gene-controlled responses involving either the A- or the E-molecule controlling loci (but never both), the responses not Ir-controlled involve participation of both A- and E-controlling loci. The lack of Ir-gene control is probably the result of complexity of the responses to multiple determinants. There is thus no principal difference between responses controlled and those not controlled by Ir genes: both types involve the recognition of the antigen, in the context of Mhc molecules.Abbreviations used in this paper A class II MHC molecule consisting of the A and A chains - ADH alcohol dehydrogenase - APC antigen-presenting cell - cpm counts per minute - E class II Mhc molecule onsisting of the E and A chains - Ir immune response - KLH key-hole limpet hemocyanin - Mhc major histocompatibility complex - PBS phosphate buffered salt solution - SD standard deviation - SI stimulation index - SN supernatant of Sendai-virus preparation  相似文献   
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