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BACKGROUND: Cytologic diagnosis of malignant fibrous histiocytoma can be problematic, as these neoplasms are known to mimic multiple other conditions. CASE: A fine needle aspirate from a 60-year-old woman was diagnosed at 2 institutions as medullary carcinoma of the breast. The patient received neo-adjuvant chemoradiotherapy before the tumor war excised. Gross pathologic examination and histomorphology on routine staining were compatible with the cytologic diagnosis. The accurate diagnosis of pleomorphic-storiform-type malignant fibrous histiocytoma was a surprise and was established with immunocytochemical stains. In retrospect, it was thought that clinical and radiologic overlap, creating a high index of suspicion for a breast neoplasm and compounding the cytologic appearance of a medullary carcinoma with spindle cell metaplasia and syncytial cells, was responsible for the error. CONCLUSION: This case highlights a potential cytodiagnostic pitfall and the importance of establishing a definitive tissue diagnosis in the face of equivocal cytologic findings. 相似文献
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OBJECTIVE: To screen cervical smears for early detection of precancerous and cancerous lesions of the uterine cervix in a hospital-based cancer screening program. STUDY DESIGN: Cervical smears were collected from women attending the gynecology outdoors of various Delhi hospitals. The smears were wet fixed, processed for Papanicolaou staining and screened cytologically. RESULTS: A total of 130,000 satisfactory smears were screened. Benign cellular changes were found in 48%. Of these, 6.9% had evidence of specific infections, while the remainder showed nonspecific, reactive changes due to inflammation/repair. In two cases, unusual, large, crescentic, septate structures were identified. These were labelled macroconidia of Fusarium species on the basis of their unique microscopic morphology. The diagnosis was confirmed on fungal culture in one case. The patient responded well to antifungal therapy. CONCLUSION: Cytology is a useful tool for identification of unusual fungi with characteristic microscopic morphology. A prompt cytodiagnosis in these cases can assist clinicians with management. 相似文献
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Kuruvilla A 《Indian journal of experimental biology》2002,40(1):7-11
Herbal medicines are popular as remedies for diseases by vast majority of world's population. Polyherbal preparations are products from medicinal plants. These are considered as safe since they are natural products. Herbal formulations which have reached widespread acceptability as therapeutic agents in India include noortropics, antidiabetics, hepatoprotective agents and lipid lowering agents. Pharmacological effects of many plants have been studied in various laboratories in India. However, there are many limitations regarding safety and efficacy of these preparations. Knowledge about active principles of herbal preparations are not well defined, information on toxicity and adverse effects of these formulations are lacking. Information regarding pharmacokinetics and bioavailability is not available. Packet inserts providing details regarding safety, and warning are not required for sale of these which are available as over the counter preparations. The risk of untested and unregulated remedies should be known to the lay public. Selection of plant material based on quality, standardisation of methods of preparation, enforcement of regulation regarding appropriate labels, are measures which will improve the quality and acceptability of herbal preparations as therapeutic agents. Documentation of research publications in journals and availability of information on website, are other measures to assist research in this field. 相似文献
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Veena S. Anil Pannaga Krishnamurthy Sam Kuruvilla K. Sucharitha George Thomas M. K. Mathew 《Physiologia plantarum》2005,124(4):451-464
Soil salinity is a major factor affecting crop productivity worldwide. This study explores mechanisms that contribute to salt tolerance in rice (Oryza sativa L.). Hydroponically grown, 2-week-old salt tolerant and sensitive indica rice varieties, Pokkali and Jaya, respectively, were exposed to a 48-h stress period with NaCl (0–250 mM). When exposed to 200 mM NaCl, micromolar levels of external Ca2+ elevated survival of both varieties. The Ca2+ levels required were lower for Pokkali than for Jaya, but resulted in significantly higher survival. Estimates of Na+ and K+ in root and shoot compartments were made by flame photometry, while X-ray microanalysis was used to localize Na+ in the extracellular matrix of the shoot. Transpirational bypass flow was estimated using the apoplastic tracer, 8-hydroxypyrene-1,3,6-trisulphonic acid, trisodium salt. Our data demonstrate a Ca2+-dependent reduction in Na+ transport to shoots, which correlated with a decline in bypass flow and of Na+ in the transpirational stream. In addition, the Na+ that enters the shoot is partitioned among several distinct compartments. Survival is inversely correlated with Na+ levels in the shoot apoplastic fluid, which surrounds the cell and influences cytosolic composition. Pokkali maintained lower Na+ in its apoplast compared with the salt sensitive Jaya at the same total shoot Na+. Na+ in the apoplast appears to be regulated by sequestration into intracellular compartments. This sink supplements the primary response of reducing Na+ influx into the shoot and effectively buffers the apoplastic fluid in Pokkali. All of these mechanisms are operational in Jaya as well but are deployed less effectively. 相似文献
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A series of acridinium derivatives 1-6, wherein steric factors have been varied systematically through substitution at the 9 position of the acridine ring, have been synthesized and their DNA interactions have been investigated by various biophysical techniques. The unsubstituted and methylacridinium derivatives 1 and 2 and the o-tolylacridinium derivative 6 exhibited high fluorescence quantum yields (Phi(f)() congruent with 1) and lifetimes (tau = 35, 34, and 25 ns, respectively), when compared with the arylacridinium derivatives 3-5. The acridinium derivatives 1 and 2 showed high DNA binding affinity (K = 7.3-7.7 x 10(5) M(-)(1)), when compared to the arylacridinium derivatives 3-5 (K = 6.9-10 x 10(4) M(-)(1)). DNA melting and viscosity studies establish that in the case of the aryl-substituted systems, the efficiency of DNA binding is in the order, phenyl > p-tolyl > m-tolyl > o-tolyl derivative. The increase in steric crowding around the acridine ring hinders the DNA binding interactions and thereby leads to negligible binding as observed in the case of 6 (o-tolyl derivative). These results indicate that a subtle variation in the substitution pattern has a profound influence on the photophysical and DNA interactions. Further, they demonstrate that pi-stacking interactions of the ligands with DNA are essential for efficient electron transfer between the DNA bases and the ligands. These water soluble and highly fluorescent molecules which differ in their DNA binding mode can act as models to study various DNA-ligand interactions. 相似文献
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