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排序方式: 共有502条查询结果,搜索用时 0 毫秒
181.
182.
Kayo Fujimaki-Aoba Kayoko Tanaka Reiko Inomata Philip J. Jensik Makoto Takada 《Cell and tissue research》2014,355(1):103-109
The epithelial sodium channel (ENaC) is involved in Na+ responses such as Na+ absorption and salt taste. The alpha ENaC subunit (α-ENaC) is expressed in the skin of both the adult and larval (tadpole) bullfrog. α-ENaC expression in the developing bullfrog embryo has not been previously investigated. In this study, the expression of α-ENaC at various stages (Sts.) of bullfrog embryonic development is assessed by western blot and immunofluorescence analysis. Bullfrog α-ENaC (α-fENaC) protein was detected by western blot in embryos at Sts. (Gosner/Shumway) 19, 21 and 25. Immunofluorescence studies indicate that α-fENaC was localized to the embryonic cement glands at St. 18 (muscular response), St. 19 (heart beat) and St. 21 (mouth open and/or cornea transparent), to the external gills at St. 21 and to the outermost cell-layer of the skin at St. 25 (operculum complete). The function(s) of ENaC in these embryonic structures remain to be elucidated. 相似文献
183.
184.
Yumiko Shoji Yoshiyuki Nishio Toru Baba Makoto Uchiyama Kayoko Yokoi Toshiyuki Ishioka Yoshiyuki Hosokai Kazumi Hirayama Hiroshi Fukuda Masashi Aoki Takafumi Hasegawa Atsushi Takeda Etsuro Mori 《PloS one》2014,9(10)
Background
The neuropsychological features and neuropathological progression patterns associated with rapidly evolving cognitive decline or dementia in Parkinson''s disease (PD) remain to be elucidated.Methods
Fifty-three PD patients without dementia were recruited to participate in a 3-year longitudinal cohort study. The patients were grouped according to the Clinical Dementia Rating (CDR). Group-wise comparisons were made with regard to demographic characteristics, motor symptoms, neuropsychological performances and 18F-fluorodeoxyglucose positron emission tomography.Results
Patients who had memory-plus cognitive impairment (patients whose CDR was 0 at baseline and 0.5 in memory and other domains at follow-up, and those whose baseline CDR was 0.5 in memory and other domains) exhibited higher age at onset, visuoperceptual impairment, non-tremor-dominant motor disturbance, rapid symptomatic progression and posterior neocortical hypometabolism. In patients who were cognitively unimpaired and those who had memory-dominant cognitive impairment (patients whose CDR was 0 at baseline and 0.5 only in memory domain at follow-up, and those whose baseline CDR was 0.5 only in memory domain), the posterior neocortex was relatively unaffected until a later stage of the disease.Conclusions
These results suggest that visuoperceptual impairment and the early involvement of the posterior neocortex may be risk factors for rapid symptomatic progression and dementia in PD. 相似文献185.
Opposing effects of circadian clock genes bmal1 and period2 in regulation of VEGF-dependent angiogenesis in developing zebrafish 总被引:1,自引:0,他引:1
Jensen LD Cao Z Nakamura M Yang Y Bräutigam L Andersson P Zhang Y Wahlberg E Länne T Hosaka K Cao Y 《Cell reports》2012,2(2):231-241
Molecular mechanisms underlying circadian-regulated physiological processes remain largely unknown. Here, we show that disruption of the circadian clock by both constant exposure to light and genetic manipulation of key genes in zebrafish led to impaired developmental angiogenesis. A bmal1-specific morpholino inhibited developmental angiogenesis in zebrafish embryos without causing obvious nonvascular phenotypes. Conversely, a period2 morpholino accelerated angiogenic vessel growth, suggesting that Bmal1 and Period2 display opposing angiogenic effects. Using a promoter-reporter system consisting of various deleted vegf-promoter mutants, we show that Bmal1 directly binds to and activates the vegf promoter via E-boxes. Additionally, we provide evidence that knockdown of Bmal1 leads to impaired Notch-inhibition-induced vascular sprouting. These results shed mechanistic insight on the role of the circadian clock in regulation of developmental angiogenesis, and our findings may be reasonably extended to other types of physiological or pathological angiogenesis. 相似文献
186.
Matsunaga S Takata H Morimoto A Hayashihara K Higashi T Akatsuchi K Mizusawa E Yamakawa M Ashida M Matsunaga TM Azuma T Uchiyama S Fukui K 《Cell reports》2012,1(4):299-308
Cohesion is essential for the identification of sister chromatids and for the biorientation of chromosomes until their segregation. Here, we have demonstrated that an RNA-binding motif protein encoded on the X chromosome (RBMX) plays an essential role in chromosome morphogenesis through its association with chromatin, but not with RNA. Depletion of RBMX by RNA interference (RNAi) causes the loss of cohesin from the centromeric regions before anaphase, resulting in premature chromatid separation accompanied by delocalization of the shugoshin complex and outer kinetochore proteins. Cohesion defects caused by RBMX depletion can be detected as early as the G2 phase. Moreover, RBMX associates with the cohesin subunits, Scc1 and Smc3, and with the cohesion regulator, Wapl. RBMX is required for cohesion only in the presence of Wapl, suggesting that RBMX is an inhibitor of Wapl. We propose that RBMX is a cohesion regulator that maintains the proper cohesion of sister chromatids. 相似文献
187.
van Kuilenburg AB Dobritzsch D Meijer J Krumpel M Selim LA Rashed MS Assmann B Meinsma R Lohkamp B Ito T Abeling NG Saito K Eto K Smitka M Engvall M Zhang C Xu W Zoetekouw L Hennekam RC 《Biochimica et biophysica acta》2012,1822(7):1096-1108
?-ureidopropionase is the third enzyme of the pyrimidine degradation pathway and catalyzes the conversion of N-carbamyl-?-alanine and N-carbamyl-?-aminoisobutyric acid to ?-alanine and ?-aminoisobutyric acid, ammonia and CO(2). To date, only five genetically confirmed patients with a complete ?-ureidopropionase deficiency have been reported. Here, we report on the clinical, biochemical and molecular findings of 11 newly identified ?-ureidopropionase deficient patients as well as the analysis of the mutations in a three-dimensional framework. Patients presented mainly with neurological abnormalities (intellectual disabilities, seizures, abnormal tonus regulation, microcephaly, and malformations on neuro-imaging) and markedly elevated levels of N-carbamyl-?-alanine and N-carbamyl-?-aminoisobutyric acid in urine and plasma. Analysis of UPB1, encoding ?-ureidopropionase, showed 6 novel missense mutations and one novel splice-site mutation. Heterologous expression of the 6 mutant enzymes in Escherichia coli showed that all mutations yielded mutant ?-ureidopropionase proteins with significantly decreased activity. Analysis of a homology model of human ?-ureidopropionase generated using the crystal structure of the enzyme from Drosophila melanogaster indicated that the point mutations p.G235R, p.R236W and p.S264R lead to amino acid exchanges in the active site and therefore affect substrate binding and catalysis. The mutations L13S, R326Q and T359M resulted most likely in folding defects and oligomer assembly impairment. Two mutations were identified in several unrelated ?-ureidopropionase patients, indicating that ?-ureidopropionase deficiency may be more common than anticipated. 相似文献
188.
Asano T Tanaka K Suemasu S Ishihara T Tahara K Suzuki T Suzuki H Fukudo S Mizushima T 《Biochemical and biophysical research communications》2012,420(2):444-449
Irritable bowel syndrome (IBS) is a gastrointestinal disorder characterized by chronic abdominal pain associated with altered bowel habits. Since the prevalence of IBS is very high and thus, involves elevated health-care costs, treatment of this condition by methods other than prescribed medicines could be beneficial. β-(1,3)-D-glucan with β-(1,6) branches (β-glucan) has been used as a nutritional supplement for many years. In this study, we examined the effect of β-glucan on fecal pellet output and visceral pain response in animal models of IBS. Oral administration of β-glucan suppressed the restraint stress- or drug-induced fecal pellet output. β-Glucan also suppressed the visceral pain response to colorectal distension. These results suggest that β-glucan could be beneficial for the treatment and prevention of IBS. 相似文献
189.
190.