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31.
During development, neurons are acutely dependent on target-derived trophic factors for survival. This dependence on trophic support decreases dramatically with maturation in several neuronal populations, including sympathetic neurons. Analyses of nerve growth factor deprivation in immature and mature sympathetic neurons indicate that maturation aborts the cell death pathway at a point that is mechanistically indistinguishable from Bax deletion. However, neither the mRNA nor protein level of BAX changes with neuronal maturation. Therefore, BAX must be regulated posttranslationally in mature neurons.Nerve growth factor deprivation in immature sympathetic neurons induces two parallel processes: (a) a protein synthesis-dependent, caspase-independent translocation of BAX from the cytosol to mitochondria, followed by mitochondrial membrane integration and loss of cytochrome c; and (b) the development of competence-to-die, which requires neither macromolecular synthesis nor BAX expression. Activation of both signaling pathways is required for caspase activation and apoptosis in immature sympathetic neurons. In contrast, nerve growth factor withdrawal in mature sympathetic neurons did not induce the translocation of either BAX or cytochrome c. Moreover, mature neurons did not develop competence-to-die with cytoplasmic accumulation of cytochrome c. Therefore, inhibition of both BAX-dependent cytochrome c release and the development of competence-to-die contributed to the loss of trophic factor dependence associated with neuronal maturation. 相似文献
32.
A M Mujumdar J N Dhuley V K Deshmukh P H Raman S L Thorat S R Naik 《Indian journal of experimental biology》1990,28(5):486-487
Piperine (1-peperoyl piperidine), a major alkaloid isolated from Piper nigrum Linn, potentiated pentobarbitone sleeping time in dose dependant manner, with peak effect at 30 min. Blood and brain pentobarbitone levels were higher in piperine treated animals. Piperine treatment in rats, treated chronically with phenobarbitone, significantly potentiated pentobarbitone sleeping time, as compared to the controls. There was no alteration in barbital sodium sleeping time. It is possible that, piperine inhibits liver microsomal enzyme system and thereby potentiates the pentobarbitone sleeping time. 相似文献
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35.
Effect of Sodium-Glucose Cotransport Inhibition on Polycystic Kidney Disease Progression in PCK Rats
Sarika Kapoor Daniel Rodriguez Meliana Riwanto Ilka Edenhofer Stephan Segerer Katharyn Mitchell Rudolf P. Wüthrich 《PloS one》2015,10(4)
The sodium-glucose-cotransporter-2 (SGLT2) inhibitor dapagliflozin (DAPA) induces glucosuria and osmotic diuresis via inhibition of renal glucose reabsorption. Since increased diuresis retards the progression of polycystic kidney disease (PKD), we investigated the effect of DAPA in the PCK rat model of PKD. DAPA (10 mg/kg/d) or vehicle was administered by gavage to 6 week old male PCK rats (n=9 per group). Renal function, albuminuria, kidney weight and cyst volume were assessed after 6 weeks of treatment. Treatment with DAPA markedly increased glucose excretion (23.6 ± 4.3 vs 0.3 ± 0.1 mmol/d) and urine output (57.3 ± 6.8 vs 19.3 ± 0.8 ml/d). DAPA-treated PCK rats had higher clearances for creatinine (3.1 ± 0.1 vs 2.6 ± 0.2 ml/min) and BUN (1.7 ± 0.1 vs 1.2 ± 0.1 ml/min) after 3 weeks, and developed a 4-fold increase in albuminuria. Ultrasound imaging and histological analysis revealed a higher cyst volume and a 23% higher total kidney weight after 6 weeks of DAPA treatment. At week 6 the renal cAMP content was similar between DAPA and vehicle, and staining for Ki67 did not reveal an increase in cell proliferation. In conclusion, the inhibition of glucose reabsorption with the SGLT2-specific inhibitor DAPA caused osmotic diuresis, hyperfiltration, albuminuria and an increase in cyst volume in PCK rats. The mechanisms which link glucosuria to hyperfiltration, albuminuria and enhanced cyst volume in PCK rats remain to be elucidated. 相似文献
36.
Jennifer L. Jones Sarika Saraswati Ashley S. Block Cheryl F. Lichti Maha Mahadevan Alan B. Diekman 《Glycoconjugate journal》2010,27(2):227-236
Galectin-3 is a β-galactoside-binding protein involved in immunomodulation, cell interactions, cancer progression, and pathogenesis
of infectious organisms. We report the identification and characterization of galectin-3 in human semen. In the male reproductive
tract, the ~30 kDa galectin-3 protein was identified in testis, epididymis, vas deferens, prostate, seminal vesicle, and sperm
protein extracts. In seminal plasma, galectin-3 was identified in the soluble fraction and in prostasomes, cholesterol-rich,
membranous vesicles that are secreted by the prostate and incorporated into seminal plasma during ejaculation. Two-dimensional
immunoblot analysis of purified prostasomes identified five galectin-3 isoelectric variants with a pI range of 7.0 to 9.2.
Affinity purification and tandem mass spectrometry of β-galactoside-binding proteins from prostasomes confirmed the presence
of galectin-3 in prostasomes and identified a truncated galectin-3 variant. The intact galectin-3 molecule contains a carbohydrate
recognition domain and a non-lectin domain that interacts with protein and lipid moieties. The identification of a monovalent
galectin-3 fragment with conserved carbohydrate-binding activity indicates the functional relevance of this truncation and
suggests a regulatory mechanism for galectin-3 in prostasomes. Surface biotinylation studies suggested that galectin-3 and
the truncated galectin-3 variant are localized to the prostasome surface. Prostasomes are proposed to function in immunosuppression
and regulation of sperm function in the female reproductive tract, are implicated in facilitating sexually-transmitted infections,
and are indicated in prostate cancer progression. Given the overlap in functional significance, the identification of galectin-3
in prostasomes lays the groundwork for future studies of galectin-3 and prostasomes in reproduction, disease transmission,
and cancer progression. 相似文献
37.
Background
Subcutaneous zygomycosis is a chronic infection caused by fungus of the order Entomophthorales. It can have varying presentations and presents in the nose and face area with gradually progressing subcutaneous swelling that may be difficult to diagnose unless a strong suspicion of fungal involvement is maintained. We present a case of subcutaneous zygomycosis in a 35-year-old male patient, resident of a North Indian state. The patient was diagnosed to be suffering from subcutaneous zygomycosis, the causative agent being Basidiobolus ranarum identified on culture and lactophenol cotton blue mount preparation. He responded well to treatment with Itraconazole and Terbinafine and is asymptomatic on follow-up. 相似文献38.
39.
Satpute NS Deshmukh SD Rao NG Tikar SN Moharil MP Nimbalkar SA 《Journal of economic entomology》2007,100(2):357-360
The toxicity of synthetic pyrethroids was found to be negatively correlated with temperature, whereas contrasting correlation was observed with the toxicity of organophosphorous compounds chlorpyriphos and quinalphos, which was most toxic at higher temperature. A similar phenomenon was observed in endosulfan at higher temperature and humidity combination. The insecticide molecules indoxacarb and spinosad were effective among the insecticides tested. Indoxacarb was effective at lower temperature, and spinosad was effective at all the temperature and relative humidity combinations with minor difference in LD50 values. During both the years, however, the levels of resistance were higher in second year compared with previous year. 相似文献
40.
Gupta S Pandey-Rai S Srivastava S Naithani SC Prasad M Kumar S 《Journal of genetics》2007,86(3):259-268
An integrated genetic linkage map of the medicinal and ornamental plant Catharanthus roseus, based on different types of molecular and morphological markers was constructed, using a F2 population of 144 plants. The map defines 14 linkage groups (LGs) and consists of 131 marker loci, including 125 molecular
DNA markers (76 RAPD, 3 RAPD combinations; 7 ISSR; 2 EST-SSR from Medicago truncatula and 37 other PCR based DNA markers), selected from a total of 472 primers or primer pairs, and six morphological markers
(stem pigmentation, leaf lamina pigmentation and shape, leaf petiole and pod size, and petal colour). The total map length
is 1131.9 cM (centiMorgans), giving an average map length and distance between two markers equal to 80.9 cM and 8.6 cM, respectively.
The morphological markers/genes were found linked with nearest molecular or morphological markers at distances varying from
0.7 to 11.4 cM. Linkage was observed between the morphological markers concerned with lamina shape and petiole size of leaf
on LG1 and leaf, stem and petiole pigmentation and pod size on LG8. This is the first genetic linkage map of C. roseus. 相似文献