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1.
Ascorbic acid metabolism was studied in guinea pigs and rats after the administration of ethanol and a high dose of ascorbic acid (AA). Male guinea pigs were maintained for 30 days as follows: (1) controls (1 mg AA/100 g body wt.); (2) ethanol (1 mg AA/100 g body wt. + 900 mg ethanol/100 g body wt); (3) ascorbic acid (25 mg AA/100 g body wt.); (4) ascorbic acid + ethanol (25 mg AA/100 g body wt. + 900 mg ethanol/100 g body wt.). Rats were also grouped into four groups as in the case of guinea pigs, but the dose of AA was 200 mg/100 g body weight. Rats adjusted to ethanol intoxication by enhancing the biosynthesis of ascorbate as evidenced by elevated activity of L-gulono lactone oxidase (GLO). Hence ascorbate levels were not lowered in rats after administration of alcohol. However, alcohol administration lowered tissue levels of ascorbate in guinea pigs. But the supplementation of ascorbate along with alcohol raised the tissue level of this vitamin. Guinea pigs responded to the ascorbate deficiency during alcohol administration by lowering the degradation of ascorbate, as seen by the lower activity of the degrading enzyme gulono lactone hydrolase. It is concluded that on the administration of alcohol, guinea pigs are dependent upon additional exogenous supplies of ascorbic acid, whereas rats are not.  相似文献   
2.
Glomerular disease is one of the most common causes of end-stage renal failure. Increasing evidence suggests that these glomerulopathies are frequently caused by primary lesions in the renal podocytes. One of the major consequences of podocyte lesions is the accumulation of mesangial matrix in the glomerular basement membrane, a process called glomerulosclerosis. Mesangial sclerosis is one of the most consistent findings in Denys-Drash patients and can be caused by dominant mutations in the Wilms' tumor 1 gene (WT1). The underlying mechanism, however, is poorly understood. WT1 is expressed in the podocytes throughout life, but its function in this cell type is unknown. Combining Wt1-knockout and inducible yeast artificial chromosome transgenic mouse models, we demonstrate that reduced expression levels of WT1 result in either crescentic glomerulonephritis or mesangial sclerosis depending on the gene dosage. Strikingly, the two podocyte-specific genes nphs1 and podocalyxin are dramatically downregulated in mice with decreased levels of Wt1, suggesting that these two genes act downstream of Wt1. Taken together, our data provide genetic evidence that reduced levels of Wt1 are responsible for the pathogenesis of two distinct renal diseases and offer a molecular explanation for the increased occurrence of glomerulosclerosis in patients with WAGR syndrome.  相似文献   
3.
Clinical Rheumatology - Consensus on treatment of idiopathic inflammatory myositis (IIM), particularly with regard to flares and interstitial lung disease (ILD), does not exist. We studied the...  相似文献   
4.
Anterior cervical discectomy and fusion (ACDF) is an established treatment for single-level cervical spondylotic myelopathy and radiculopathy, yet its stand-alone use for multi-level disease of the subaxial cervical spine remains controversial. We report a prospectively studied case series of 30 patients receiving polyetheretherketone (PEEK) cage fusion over three and four cervical levels without anterior plating. Seven (23.3%) four-level procedures (all C3 to C7) were performed, the other 23 (76.7%) being three-level, with 19 (64.4%) at C4 to C7 and four (12.3%) at C3 to C6. Long-term follow-up of more than 2 years was available in 67% of patients. This cohort showed statistically significant improvements in visual analogue score for neck pain (p = 0.0006), arm pain (p = 0.0003) and Japanese Orthopaedic Association myelopathy score (p = 0.002). Fused segment heights increased by 0.6–1.1%. Adjacent segment disease requiring ACDF at C3–4 was seen in 6.7% of patients (one after trauma) at a mean follow-up of 62 months. Same segment recurrence requiring posterior decompression with instrumented fusion was found in 10% of patients at a mean follow-up of 49 months, only one of whom had radiological evidence of cage subsidence. The results suggest the procedure is safe and effective with potentially less morbidity than anterior plating, shorter inpatient stays than posterior approaches, acceptable same segment recurrence and lower than predicted adjacent segment disease rates.  相似文献   
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Epizootic hemorrhagic disease virus (EHDV) was isolated from a pregnant cow in Indiana, USA, exhibiting excessive salivation, pyrexia and abortion. VP2, VP5, and VP7 sequences of the isolated bovine EHDV showed 97.7, 97.4, and 97.9 % identity to a serotype 2 reference virus. Bovine EHDV was closely related (>99.9 %) to white tailed deer (WTD) EHDV collected from Iowa in 2013 and showed less than 2.1 % divergence from EHDV collected from WTD across the USA in 2013. The high degree of sequence identity between bovine and WTD EHDV isolates demonstrates that similar viruses concurrently circulate in both species and suggests possible further incursions into bovines.  相似文献   
7.
Correction for ‘Consequences of gamma-ray irradiation on structural and electronic properties of PEDOT:PSS polymer in air and vacuum environments’ by Aswin kumar Anbalagan et al., RSC Adv., 2021, 11, 20752–20759, DOI: 10.1039/D1RA03463D.

The authors regret that incorrect details were given for ref. 18. The correct version of ref. 18 is given here as ref. 1.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
8.
Sociality is a complex phenomenon that involves the individual´s motivation to approach their conspecifics, along with social cognitive functions that enable individuals to interact and survive. The nonapeptide oxytocin (OXT) is known to regulate sociality in many species. However, the role of OXT in specific aspects of sociality is still not well understood. In the present study, we investigated the contribution of the OXT receptor (OXTR) signalling in two different aspects of zebrafish social behaviour: social preference, by measuring their motivation to approach a shoal of conspecifics, and social recognition, by measuring their ability to discriminate between a novel and familiar fish, using a mutant zebrafish lacking a functional OXTR. Although oxtr mutant zebrafish displayed normal attraction to a shoal of conspecifics, they exhibited reduced social recognition. We further investigated whether this effect would be social‐domain specific by replacing conspecific fish by objects. Although no differences were observed in object approach, oxtr mutant fish also exhibited impaired object recognition. Our findings suggest that OXTR signalling regulates a more general memory recognition of familiar vs novel entities, not only in social but also in a non‐social domain, in zebrafish.  相似文献   
9.
Neurotoxicity Research - Cerebral ischemia-reperfusion (C I/R) accelerates neuronal injury through the overproduction of reactive oxygen species due to mitochondrial dysfunction. Hesperidin has...  相似文献   
10.
Since the cyanide ion is used in a wide range of industries and is harmful to both human health and the environment, a number of research efforts are dedicated to creating fluorescence sensors for the detection of cyanide (CN). Herein, for the fluorescence detection of CN, a new highly selective and sensitive sensor 2-(3-(benzo[d]thiazol-2-yl)-4-hydroxybenzylidene)-1H-indene-1,3(2H)-dione (BID) was created by conjugating a benzothiazole moiety with 1H-indene-1,3(2H)-dione. The donor and acceptor components of this hybrid receptor were covalently connected through a double bond. The nucleophilic addition of a cyanide anion to the BID inhibits the intramolecular charge transfer (ICT) transition, resulting in spectral and colour alterations in the receptor. When the solvent polarity was increased from n-hexane to methanol, this molecule exhibited a bathochromic shift in the emission wavelength (610 to 632 nm), suggesting the presence of a solvatochromic action. The sensor BID has shown strong specificity towards CN by interrupting its internal charge transfer (ICT), resulting in a significant change in the UV-vis spectrum and a notable blue shift in the fluorescence emission spectrum. The cyanide anion (CN) is responsible for the optical alterations observed by BID, as opposed to the other anions examined. The detection limit was 5.97 nM, significantly less than the WHO''s permitted amount of CN in drinking water. The experimental findings indicate that BID''s fluorescence response to CN is pH insensitive throughout a wide pH range of 6.0 to 12.0. The interaction mechanism between the BID and CN ions has been studied by HRMS, 1H-NMR titration experiments, FT-IR, and DFT, which confirmed the nucleophilic addition of CN on vinylidene and subsequent disturbance of ICT. Additionally, we demonstrated the real-time detection application of CN in environmental water samples and live-cell imaging.

Since the cyanide ion is used in a wide range of industries and is harmful to both human health and the environment, a number of research efforts are dedicated to creating fluorescence sensors for the detection of cyanide (CN).  相似文献   
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