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BackgroundThe majority of population rely on traditional medicine as a source of healthcare. Artemisia afra is a plant traditionally used for its medicinal values, including treatment of malaria in many parts of the world. Currently, it is also attracting attention because of a claim that a related species, Artemisia annua, is a remedy for the COVD-19 pandemic. The aim of the present study was to investigate toxic effects of A. afra on brain, heart and suprarenal glands in mice aged 8–12 weeks and weighing 25–30g.MethodsLeaves of A.afra were collected from Bale National Park, dried under shade, crushed into powder and soaked in distilled water to yield aqueous extract for oral administration. For acute toxicity study, seven treated and one control groups, with 3 female mice each, were used. They were given a single dose of 200mg/kg, 700mg/kg, 1200mg/kg, 2200mg/kg, 3200mg/kg, 4200mg/kg or 5000mg/kg b/wt of the extract. For the sub-acute toxicity study, two treated and one control groups, with 5 female and 5 male mice each, were used. They were daily treated with 600mg/kg or 1800mg/kg b/wt of extract.ResultsLD50 was found to be greater than 5000mg/kg indicating that the plant is relatively safe. In the sub-acute study, no signs of toxicity were observed in all treatment groups. On microscopic examination of the brain, heart and suprarenal glands no sign of cellular injury was observed.ConclusionThe findings of this study suggest that the leaves extract of A. afra is relatively safe in mice.  相似文献   
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Exposure to unsafe level of aflatoxin in early life may lead to growth faltering. However, the extent of contamination of breast milk and complementary foods is poorly examined. We determined aflatoxin M1 (AFM1) and B1 (AFB1) contamination of human breast milk and cereal‐based cooked complementary foods, respectively, among households having children 6–23 months of age in Sidama zone, southern Ethiopia. Data were collected through two cross‐sectional surveys implemented in the wet (n = 180) and dry (n = 180) seasons. Eligible households (n = 360) were recruited from three agroecological zones (lowland, midland and highland, each with sample size of 120) using a multistage sampling technique. AFB1 and AFM1 levels were determined using enzyme‐linked immunosorbent assay. Mann–Whitney U and Kruskal–Wallis tests were performed to compare aflatoxin levels between seasons and across the agroecological zones. Among 360 breast milk samples tested, 64.4% had detectable AFM1 and 5.3% exceeded the 0.025 parts per billion (ppb) limit set by the European Union for infant milk. The median AFM1 in the lowlands was significantly higher than in the other agroecological settings (P < 0.001). By season, AFM1 was higher in breast milk samples collected in the dry season (P = 0.041). AFB1 was detected in 96.4% of the food samples tested, and 95.0% had concentration exceeding the permissible European Union limit of 0.1 ppb. The median AFB1 was significantly higher in the lowland (P = 0.002), but there was no difference between the seasons (P = 0.386). The study indicated that, in southern Ethiopia, foods intended for infants are heavily contaminated with AFB1. Contamination of breast milk is also a significant health concern.  相似文献   
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Controversies regarding the development of the mammalian infrahepatic inferior caval and azygos veins arise from using topography rather than developmental origin as criteria to define venous systems and centre on veins that surround the mesonephros. We compared caudal‐vein development in man with that in rodents and pigs (rudimentary and extensive mesonephric development, respectively), and used Amira 3D reconstruction and Cinema 4D‐remodelling software for visualisation. The caudal cardinal veins (CCVs) were the only contributors to the inferior caval (IVC) and azygos veins. Development was comparable if temporary vessels that drain the large porcine mesonephros were taken into account. The topography of the CCVs changed concomitant with expansion of adjacent organs (lungs, meso‐ and metanephroi). The iliac veins arose by gradual extension of the CCVs into the caudal body region. Irrespective of the degree of mesonephric development, the infrarenal part of the IVC developed from the right CCV and the renal part from vascular sprouts of the CCVs in the mesonephros that formed ‘subcardinal’ veins. The azygos venous system developed from the cranial remnants of the CCVs. Temporary venous collaterals in and around the thoracic sympathetic trunk were interpreted as ‘footprints’ of the dorsolateral‐to‐ventromedial change in the local course of the intersegmental and caudal cardinal veins relative to the sympathetic trunk. Interspecies differences in timing of the same events in IVC and azygos‐vein development appear to allow for proper joining of conduits for caudal venous return, whereas local changes in topography appear to accommodate efficient venous perfusion. These findings demonstrate that new systems, such as the ‘supracardinal’ veins, are not necessary to account for changes in the course of the main venous conduits of the embryo.  相似文献   
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Although the intrinsic muscles of the back are defined by their embryological origin and innervation pattern, no detailed study on their development is available. Human embryos (5–10 weeks development) were studied, using Amira3D® reconstruction and Cinema4D® remodeling software for visualization. At Carnegie Stage (CS)15, the epaxial portions of the myotomes became identifiable laterally to the developing vertebrae. At CS16, these portions fused starting cranially to form a longitudinal muscle column, which became innervated by the dorsal branches of the spinal nerves. At CS17, the longitudinal muscle mass segregated into medial and lateral columns (completed at CS18). At CS18, the medial column segregated again into intermediate and medial columns (completed at CS20). The lateral and intermediate columns did not separate in the lower lumbar and sacral regions. Between CS20 and CS23, the cervical portions of the three columns segregated again from lateral to medial resulting ventrolaterally in rod‐like continuations of the caudal portions of the columns and dorsomedially in spade‐like portions. The observed topography identifies the iliocostalis and splenius as belonging to the lateral column, the longissimus to the intermediate column, and the (semi‐)spinalis to the medial column. The medial (multifidus) group acquired its transversospinal course during closure of the vertebral arches in the early fetal period. Hence, the anatomical ontology of the epaxial muscles is determined by craniocaudal and lateromedial gradients in development. Three longitudinal muscle columns, commonly referred to as the erector spinae, form the basic architectural design of the intrinsic muscles of the back. Clin. Anat. 29:1031–1045, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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