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81.
Congenital muscular dystrophies (CMD) are a group of heterogeneous inherited autosomal recessive disorders characterized by muscular weakness, hypotonia and contractures. The Merosin Negative CMD (MNCMD) is considered to be the most severe form and is usually associated with white matter abnormalities as seen with brain imaging. Merosin is also expressed in the nervous system and its deficiency could affect its development. This article describes the clinical picture, muscle biopsy findings and neuroimaging abnormalities of eight Egyptian Pediatric patients with the clinical presentation of merosin negative congenital muscular dystrophy. The leading clinical presentation in almost all patients was severe hypotonia, muscular weakness and failure to achieve motor developmental milestones, only Case 2 walked at 2 years of age. Mentality was normal in most patients with exception of Case 2 in whom scholastic achievement was poor and was associated with behavior abnormality. Serum Creatine kinase ranged from moderate to severe elevation, 536–3563 U/L, Electromyography demonstrated a myopathic pattern in all patients. Brain MRI showed extensive demyelination of the cerebral white matter in 6/8 patients with extension to cerebellar demyelination in Case 5. 5/8 patients underwent muscle biopsy for which immunofluorescence staining for merosin demonstrated complete deficiency of laminin α2 in Case 5 & partial deficiency of laminin α2 in Case 2.This report demonstrates the utility of Immunofluorescence staining as a guide to confirm the diagnosis of MDCMD especially when molecular diagnosis is not available.  相似文献   
82.
83.
In this study, among a collection of heavy metals resistant endophytic bacterial strains isolated from aquatic hyperaccumulator plant (Eichhornia crassipes), one plant growth promoting endophytic bacteria (PGPE), SVUB4 was selected for its ability to utilize 1-aminocyclopropane-1-carboxylic acid (ACC) as the sole N source and accumulate different heavy metals. The SVUB4 strain was characterized as Enterobacter sp. on the basis of its 16S rDNA sequences. Assessment of the parameters of plant growth promotion revealed the intrinsic ability of the strain for the production of IAA, siderophore and solubilization of insoluble phosphate. Furthermore, plasmid DNA analysis of Enterobacter sp. strain SVUB4 indicated the presence of a single large plasmid element. The results of plasmid curing experiments demonstrated that the ability of this strain to grow in presence of Cd and Zn was encoded by the 98 kb plasmid, whereas the ability to grow in the presence of Pb appeared to be encoded by the chromosome. The Cd and Zn removal capacity of the respective metal sensitive strain (plasmidless) were about 36 and 45 μg/g-1 DW, respectively, while the removal capacity of the both metal by metal resistant strain (p SVUB4) showed a significantly higher Cd and Zn removal capacity of 153 and 228 μg/g?1 DW, respectively. However, both strains exhibited a similar pattern of Pb accumulation. The present observation also showed that for wild-type strain SVUB4 (pSVUB4), the overall level of IAA production in the absence and in the presence of Cd2+ or Zn2+was approximately the same. Nevertheless, strain SVUB4M in this respect appeared to be more sensitive to heavy metals: a noticeable decrease in IAA production was observed under the effect of both metals, especially with Cd2+.  相似文献   
84.
Abstract

Acne vulgaris is the most common dermatological disorder affecting millions of individuals. Acne therapeutic solutions include topical treatment with retinoic acid (RA) which showed a good efficacy in treatment of mild and moderate cases. However, the high prevalence of adverse events, such as skin dryness, shedding and skin irritation affects the patient convenience and obstruct the acne treatment. Thus, the objective of this paper was to produce Span 60 based elastic vesicles enriched with penetration enhancers, and study their influence on the delivery of RA and its skin irritation. RA-loaded nanovesicles, enriched with Transcutol®/Labrasol®, were made using the thin film hydration technique, and assessed for entrapment efficiency, particle size and zeta potential. The optimized RA-loaded nanovesicles (composed of Span 60-Tween 20, and Transcutol®) were morphologically assessed via transmission electron microscopy. Moreover, RA deposition into newborn mice skin was assessed in vitro under non-occlusive conditions, where the optimized RA-loaded nanovesicles showed 2-fold higher RA deposition in the skin compared to the corresponding one lacking Transcutol. The optimized RA-loaded nanovesicles incorporated into 1% carbopol gel was evaluated for in-vivo clinical performance in acne patients, and showed appreciable advantages over the marketed formulation (Acretin®) in the treatment of acne regarding skin tolerability and patient’s compliance.  相似文献   
85.
Epidural analgesia is considered the standard of care but cannot be provided to all patients Liposomal bupivacaine has been approved for field blocks such as transversus abdominis plane (TAP) blocks but has not been clinically compared against other modalities. In this retrospective propensity matched cohort study we thus tested the primary hypothesis that TAP infiltration are noninferior (not worse) to continuous epidural analgesia and superior (better) to intravenous opioid analgesia in patients recovering from major lower abdominal surgery. 318 patients were propensity matched on 18 potential factors among three groups (106 per group): 1) TAP infiltration with bupivacaine liposome; 2) continuous Epidural analgesia with plain bupivacaine; and; 3) intravenous patient-controlled analgesia (IV PCA). We claimed TAP noninferior (not worse) over Epidural if TAP was noninferior (not worse) on total morphine-equivalent opioid and time-weighted average pain score (10-point scale) within first 72 hours after surgery with noninferiority deltas of 1 (10-point scale) for pain and an increase less of 20% in the mean morphine equivalent opioid consumption. We claimed TAP or Epidural groups superior (better) over IV PCA if TAP or Epidural was superior on opioid consumption and at least noninferior on pain outcome. Multivariable linear regressions within the propensity-matched cohorts were used to model total morphine-equivalent opioid dose and time-weighted average pain score within first 72 hours after surgery; joint hypothesis framework was used for formal testing. TAP infiltration were noninferior to Epidural on both primary outcomes (p<0.001). TAP infiltration were noninferior to IV PCA on pain scores (p = 0.001) but we did not find superiority on opioid consumption (p = 0.37). We did not find noninferiority of Epidural over IV PCA on pain scores (P = 0.13) and nor did we find superiority on opioid consumption (P = 0.98). TAP infiltration with liposomal bupivacaine and continuous epidural analgesia were similar in terms of pain and opioid consumption, and not worse in pain compared with IV PCA. TAP infiltrations might be a reasonable alternative to epidural analgesia in abdominal surgical patients. A large randomized trial comparing these techniques is justified.  相似文献   
86.
The changes of some physiological and biochemical parameters in pumpkin (Cucurbita pepo cv Eskandarani) leaves associated with zucchini yellow mosaic virus (ZYMV) infection and the effect of exogenous application of salicylic acid (SA) were studied in this paper. In comparison to the untreated leaves, ZYMV infected leaves showed many symptoms, including severe mosaic, size reduction, stunting and deformation. Results from analysis of physiological parameters indicated that viral infection and SA treatments affected metabolism. Viral infection decreased pigment, protein and carbohydrate levels. But with all SA treatments, the protein and carbohydrate contents are noticeably increased. Moreover, the other biochemical parameters showed variable alterations. The peroxidase (POX, EC 1.11.1.7) activity and proline contents were induced by both viral infection and SA treatments. In addition, protein patterns represent some newly synthesized polypeptides which reflect formation of pathogenesis related proteins in all treatments. SA treatment increases the plant resistance against ZYMV. This can be noticed through reduction of percentage of the infected plants, decrease in disease severity and virus concentration of the plants treated with SA then inoculated with virus. All results show significant changes in metabolism affected by either viral infection or SA treatments and also indicate that exogenous SA plays an important role in induction of defense mechanism against ZYMV infection.  相似文献   
87.
Chickpea yield is decreasing day by day due to drought stress, which could be an immense risk for future food security in developing countries. Management practices could be the most excellent approach to diminish loss due to this abiotic factor. The current research work was designed to explore the tolerance reaction of chickpea genotypes against management practices, through morphological and biochemical parameters and evaluate yield performance across drought prone location of Bangladesh. Four genotypes BD-6048, BD-6045, BD-6090, BD-6092 and eight management practices, e.g., severe water stress (SWS), i.e., without irrigation, 10 cm thick mulching with rice straw (MRS), 10 cm thick mulching with water hyacinth (MWH), organic amendment through compost (OAC) @ 3 t ha−1, organic amendment through cow dung @ 5 t ha−1 (OACD), organic amendment through poultry manure @ 2 t ha−1 (OAPM), inorganic amendment through proline application (IAPA) as foliar spray and 16 h hydro-priming (HP). The study revealed that the genotypes BD-6048 showed excellent performance because of the highest chlorophyll, carotenoids, phosphorus, potassium, proline and protein content. The highest pod number plant−1 also increased seed yield in BD-6048. Considering management practices, IAPA increased relative water content, carotenoids, leaf phosphorus and potassium compared to other management practices and severe water stress. Finally, BD-6084 was selected as best genotype because of a significant increase in chlorophyll a and b, carotenoids, and relative water content with IAPA. Identified top performing genotypes can be used for releasing variety and cultivated for sustainable production in drought prone area of Bangladesh.  相似文献   
88.
A rapid and accurate assay for evaluating antibabesial drugs on a large scale is required for the discovery of novel chemotherapeutic agents against Babesia parasites. In the current study, we evaluated the usefulness of a fluorescence-based assay for determining the efficacies of antibabesial compounds against bovine and equine hemoparasites in in vitro cultures. Three different hematocrits (HCTs; 2.5%, 5%, and 10%) were used without daily replacement of the medium. The results of a high-throughput screening assay revealed that the best HCT was 2.5% for bovine Babesia parasites and 5% for equine Babesia and Theileria parasites. The IC50 values of diminazene aceturate obtained by fluorescence and microscopy did not differ significantly. Likewise, the IC50 values of luteolin, pyronaridine tetraphosphate, nimbolide, gedunin, and enoxacin did not differ between the two methods. In conclusion, our fluorescence-based assay uses low HCT and does not require daily replacement of culture medium, making it highly suitable for in vitro large-scale drug screening against Babesia and Theileria parasites that infect cattle and horses.  相似文献   
89.
A marine bacterial strain putatively identified asBacillus thuringiensis strain DM55, showed multiple heavy metal resistance and biosorption phenotypes. Electron microscopic studies revealed that DM55 cells are encased in anionic cell wall polymers that can immobilize discrete aggregates of cations. Factors affecting cell surface affinity for metal cations, monitored by means of Cd2+ binding capability, are investigated. The mechanisms of cadmium resistance and Cd2+ biosorption by the bacterium appeared to be inducible and coincident. Medium components affecting metal removal under cadmium-stressed growth conditions were explored based on the application of two sequential multi-factorial statistical designs. Concentrations of potassium phosphates and peptone were the most significant variables. Optimized culture conditions allowed DM55 cells grown in the presence of 0.25 mM CdCl2 to remove about 79% of the metal ions within 24 h with a specific biosorption capacity of 21.57 mg g–1 of biomass. Both fresh and dry cells of DM55 prepared under cadmium-free optimal nutrient condition were also able to biosorb Cd2+. In addition to the concentration of phosphate in the medium, KinA, a major phosphate provider in the phosphorelay of Bacillus cells, was also demonstrated to regulate the magnitude of cell surface affinity for cadmium ions.  相似文献   
90.
When trypsin-dissociated liver cells from 17-day chick embryos were grown in regular minimum essential medium, mixed hepatocyte-fibroblast cultures resulted. When D-valine was substituted for L-valine in this medium, fibroblast growth was suppressed, leaving virtually pure hepatocyte cultures. Tyrosine aminotransferase activity is induced by cortisol in mixed cultures. No induction of enzyme activity is observed with cortisol exposure to hepatocytes, grown in D-valine. However, when cortisol-containing medium is conditioned by pre-incubation with mixed cells and then transferred to hepatocytes, tyrosine aminotransferase activity is induced. Enzyme activity is also induced in mixed cells incubated in D-valine medium in the presence of cortisol. It appears that a substance produced in the presence of fibroblasts exposed to cortisol is capable of inducing tyrosine aminotransferase activity in hepatocytes. This activity, which we have termed fibroblast hepatocyte factor, is heat stable, of low molecular weight, and antigenically different from fibroblast pneumonocyte factor, a factor similar to that produced by lung fibroblasts exposed to cortisol.  相似文献   
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