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Md Ayub Ali Ashutosh Nath Md Midul Islam Sharmin Binte Shaheed Ifat Nur Dibbo 《RSC advances》2022,12(18):11255
Amides are the most extensively used substances in both synthetic organic and bioorganic chemistry. Unfortunately, the traditional synthesis of amides suffers from some important drawbacks, including low atom efficiency, high catalyst loading, separation of products from the reaction mixture and production of byproducts. Al2O3 is an amphoteric catalyst that activates the carbonyl carbon of the secondary amide group and helps the C–N cleavage of the reactant amide group by attacking the N–H hydrogen. By using the concepts of amphoteric properties of Al2O3, amides were synthesized from secondary amides and amines in the presence of triethylamine solvent. Several aliphatic and aromatic amines were used for the transamidation of N-methylbenzamide in the presence of the Al2O3 catalyst. Moreover, using the Gaussian09 software at the DFT level, HUMO, LUMO and the intrinsic reaction coordinates (IRCs) have also been calculated to find out the transition state of the reaction and energy. In this study, five successful compounds were synthesized by the transamidation of secondary amides with amines using a reusable Al2O3 catalyst. The catalyst was reused several times with no significant loss in its catalytic activity. The products were purified by recrystallization and column chromatography techniques. This catalytic method is effective for the simultaneous activation of the carbonyl group and N–H bond by using the Al2O3 catalyst.Amides are the most extensively used substances in both synthetic organic and bioorganic chemistry. 相似文献
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Yael Kuperman Orna Issler Limor Regev Ifat Musseri Inbal Navon Adi Neufeld-Cohen Shosh Gil Alon Chen 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(18):8393-8398
In response to physiological or psychological challenges, the brain activates behavioral and neuroendocrine systems linked to both metabolic and emotional outputs designed to adapt to the demand. However, dysregulation of integration of these physiological responses to challenge can have severe psychological and physiological consequences, and inappropriate regulation, disproportional intensity, or chronic or irreversible activation of the stress response is linked to the etiology and pathophysiology of mood and metabolic disorders. Using a transgenic mouse model and lentiviral approach, we demonstrate the involvement of the hypothalamic neuropeptide Urocortin-3, a specific ligand for the type-2 corticotropin-releasing factor receptor, in modulating septal and hypothalamic nuclei responsible for anxiety-like behaviors and metabolic functions, respectively. These results position Urocortin-3 as a neuromodulator linking stress-induced anxiety and energy homeostasis and pave the way toward better understanding of the mechanisms that mediate the reciprocal relationships between stress, mood and metabolic disorders. 相似文献
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Salvatore JR Sarid R Harrington J Shah I Kummet T 《Medical oncology (Northwood, London, England)》2003,20(4):413-424
Primary extranodal non-Hodgkin’s lymphoma of the transverse colon is a rare presentation of non-Hodgkin’s lymphoma or colonic
neoplasm. Dermatomyositis is an autoimmune condition of the skin, muscle, and blood vessels that when associated with malignancy
is a true paraneoplastic syndrome but is rarely associated with non-Hodgkin’s lymphoma. We present a case of primary non-Hodgkin’s
lymphoma of the transverse colon diagnosed after the presentation of dermatomyositis and review the literature on dermatomyositis
and hematologic neoplasm. 相似文献
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BACKGROUND: Although the "two-bite" technique (obtaining 2 mucosal biopsy specimens with a single passage of the forceps) is used routinely, the adequacy of the second biopsy for histopathologic examination has not been evaluated. Our hypothesis was that the second sample will be inadequate for this purpose. The aim of this study was to prospectively assess the adequacy of mucosal biopsy specimens obtained with 3 different types of forceps with the two-bite technique. METHODS: Patients undergoing diagnostic EGD were prospectively enrolled in the study. In each patient, mucosal biopsy specimens were obtained as follows: 4 specimens with the two-bite technique in 2 separate passages of the forceps (one from the esophagus followed by one from the stomach, and one from the stomach followed by one from the esophagus, the order being chosen randomly) and 2 single-bite specimens from the same anatomic locations (esophagus and stomach). Each patient underwent the same biopsy sampling sequence with 3 different forceps. An experienced pathologist blinded to the sequence and technique of obtaining the samples and the forceps used evaluated the specimens for number submitted, integrity, and adequacy for histopathologic diagnosis and depth of the sample as assessed by the presence or absence of muscularis mucosae. RESULTS: A total of 288 mucosal samples were obtained from 16 patients. Of these, 192 were taken by using the two-bite technique. Thirty-five (18.2%) samples were missing when the two-bite technique was used compared with only 2 (2.1%) when the single bite technique was used (p < 0.05). Irrespective of the location from which the first mucosal sample was taken, a significantly greater number of first samples were lost (25%) compared with second samples (11.5%) (p < 0.05). The forceps without a spike was associated with significantly more missing samples than the spiked forceps (28.1% vs. 13.3%; p = 0.01). At histopathologic evaluation, there were no significant differences between first and second samples nor differences between samples taken with the two-bite and the single-bite techniques with regard to adequacy, integrity, and depth. With respect to histopathologic evaluation, there were no differences among the 3 types of forceps used in the study. CONCLUSIONS: Although the second mucosal sample obtained with the two-bite technique is adequate for histopathologic purposes, there is a significant risk of losing samples (the first one in particular) with this technique, and thus an increase in the probability of sampling error. This may be particularly true for forceps without a spike. 相似文献
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Ifat Gamliel Nurit Yirmiya Dena H. Jaffe Orly Manor Marian Sigman 《Journal of autism and developmental disorders》2009,39(8):1131-1144
We compared the cognitive and language development at 4, 14, 24, 36, 54 months, and 7 years of siblings of children with autism
(SIBS-A) to that of siblings of children with typical development (SIBS-TD) using growth curve analyses. At 7 years, 40% of
the SIBS-A, compared to 16% of SIBS-TD, were identified with cognitive, language and/or academic difficulties, identified
using direct tests and/or parental reports. This sub-group was identified as SIBS-A-broad phenotype (BP). Results indicated
that early language scores (14–54 months), but not cognitive scores of SIBS-A-BP and SIBS-A-nonBP were significantly lower
compared to the language scores of SIBS-TD, and that the rate of development was also significantly different, thus pinpointing
language as a major area of difficulty for SIBS-A during the preschool years. 相似文献