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11.
In the present study, we investigated the effect of fluoropyrimidines on the growth of Ureaplasma urealyticum. Addition of fluoropyrimidines strongly inhibited bacterial growth. Growth inhibition by these analogues could be reversed by addition of either thymidine or deoxyuridine, suggesting inhibition of thymidylate biosynthesis as the mechanism in operation.  相似文献   
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Mammalian Genome - Polycystic ovary syndrome, previously known as Stein–Leventhal syndrome, is associated with altered reproductive endocrinology, predisposing a young woman towards the risk...  相似文献   
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There has been a renewed interes in testicular biopsy to evaluate infertility since the introduction, in 1993, of ICSI in azoospermic men with testicular sperm extraction (TESE) and intracytoplasmic sperm injection for the treatment of obstructive azoospermia. TESE is now performed for the treatment of nonobstructive azoospermia, and the testicular material sampled for therapeutic purposes can also be used for diagnostic and research purposes. The development of new methods of investigation of spermatogenesis, such as immunocytochemistry and fluorescent in situ hybridization (FISH) have also led to a renewed interest in analysis of spermatogenesis on testicular biopsy. A precise “testicular phenotype” must now be established to propose an aetiological diagnosis, and to determine the mechanisms and risks of nonobstructive azoospermia and severe oligozoospermia for the embryo. We systematically perform testicular histopathology and meiotic study for each patient undergoing testicular biopsy for ICSI. We first describe the histopathological lesions. Examination of the testicular biopsy specimen determines whether the lesion is focal or diffuse. If it is focal, the percentage of altered tubules, evaluated on 50 tubules, should be calculated. Quantitative evaluation of seminiferous epithelium and a qualitative study of cell morphology must also be performed. There are four frequent lesion patterns: 1-Sertoli-cell-only syndrome; 2-tubular hyalinisation; 3-diffuse lesions in spermatogenesis; 4-mixed atrophy. However, the reliability of interpretation of testicular histology presents certain limitations, as no standard method of analysis of testicular biopsies has been defined and there is a marked variability in the histologist’s capacity to recognize the various histological patterns. Meiotic study is performed on the cell suspension remaining after ICSI, which contains immature germ cells. New methods using immunocytochemistry have replaced older methods. The panel of antibodies which detect individual protein components at different stages of meiosis provides a valuable tool for the detection and interpretation of abnormal meiotic profiles. We performed meiotic studies on 41 patients and 13 controls after Giemsa staining, and synaptonemal complexes (SC) from nine of these patients and one control were immunostained with a polyclonal antibody which recognizes the COR1/SCP3 protein of the lateral element of the SC. Nineteen of the patients presented obstructive infertility (O) and 22 presented nonobstructive infertility (NO). We showed that the rate of asynaptic nuclei from the NO group (25.4%) was significantly higher than that of the O group (9.8%) and the controls (9.8%). Two patients of the NO group had a high percentage of asynaptic nuclei (86% and 91.8%), which could arise from a primary meiotic defect. One of these patients had an AZFc microdeletion. The meiotic study in a patient with classical complete AZFb microdeletion revealed a high prevalence of early meiotic stages: leptotene, zygotene and early pachytene stages and marked impairment of the synaptic process in most spermatocytes. In the light of these findings, we conclude that the pachytene checkpoint is localized at the mid-pachytene stage in humans.  相似文献   
14.

Background

Since December 2009, Médecins Sans Frontières has diagnosed and treated patients with visceral leishmaniasis (VL) in Tabarak Allah Hospital, eastern Gedaref State, one of the main endemic foci of VL in Sudan. A survey was conducted to estimate the VL incidence in villages around Tabarak Allah.

Methods

Between the 5th of May and the 17th of June 2011, we conducted an exhaustive door-to-door survey in 45 villages of Al-Gureisha locality. Deaths were investigated by verbal autopsies. All individuals with (i) fever of at least two weeks, (ii) VL diagnosed and treated in the previous year, and (iii) clinical suspicion of post-kala-azar dermal leishmaniasis (PKDL) were referred to medical teams for case ascertainment. A new case of VL was a clinical suspect with a positive rk39 rapid test or direct agglutination test (DAT).

Results

In the 45 villages screened, 17,702 households were interviewed, for a population of 94,369 inhabitants. The crude mortality rate over the mean recall period of 409 days was 0.13/10''000 people per day. VL was a possible or probable cause for 19% of all deaths. The VL-specific mortality rate was estimated at 0.9/1000 per year.The medical teams examined 551 individuals referred for a history of fever of at least two weeks. Out of these, 16 were diagnosed with primary VL. The overall incidence of VL over the past year was 7.0/1000 persons per year, or 7.9/1000 per year when deaths possibly or probably due to VL were included. Overall, 12.5% (11,943/95,609) of the population reported a past VL treatment episode.

Discussion and Conclusion

VL represents a significant health burden in eastern Gedaref State. Active VL case detection had a very low yield in this specific setting with adequate access to care and may not be the priority intervention to enhance control in similar contexts.  相似文献   
15.
Molecular Biology Reports - Mitochondrial diseases are a clinically heterogeneous group of multisystemic disorders that arise as a result of various mitochondrial dysfunctions. Autosomal recessive...  相似文献   
16.
The dipeptidyl peptidase-IV (DPP-IV) inhibitory activity of Khaya senegalensis extracts was evaluated. The DPP-IV from a rat kidney was purified to a purification fold of 2.3. Among extracts from K. senegalensis, the hexane extract had the best DPP-IV inhibitory activity, with IC50 value of 1.56±0.61 μg/mL and was fractionated to eleven fractions (A–K). Fraction I had the best DPP-IV inhibition via uncompetitive pattern. GC-MS analysis of fraction I showed that the major bioactive compounds were 3-amino-3-hydroxyimino-N-phenylpropanamide ( 1 ) and 11-(2-cyclopenten-1-yl)undecanoic acid ( 2 ), with good binding affinities toward DPP-IV, based on molecular docking,. They were then subjected to molecular dynamic simulation using WEBGRO and utilizing a GROMACS system for 100 ns. The 3-amino-3-hydroxyimino-N-phenylpropanamide-DPP-IV complex was more stable and compact than the other complex. K. senegalensis contains compounds like 1 that might be used for the design of new DPP-IV inhibitors.  相似文献   
17.
The effect of sodium dodecyl sulphate, urea, guanidinium hydrochloride and heat on the oligomeric structure of the 11 S protein of sunflower has been determined. Sodium dodecyl sulphate directly dissociates the protein to 2 S subunits, whereas urea and guanidinium hydrochloride dissociate it through an intermediate 7 S protein. Heating the protein at 90‡C for 20 min caused dissociation of the 11 S protein, without any precipitation.  相似文献   
18.
Environmental microbial communities are key players in the bioremediation of hydrocarbon pollutants. Here we assessed changes in bacterial abundance and diversity during the degradation of Tunisian Zarzatine oil by four indigenous bacterial consortia enriched from a petroleum station soil, a refinery reservoir soil, a harbor sediment and seawater. The four consortia were found to efficiently degrade up to 92.0% of total petroleum hydrocarbons after 2 months of incubation. Illumina 16S rRNA gene sequencing revealed that the consortia enriched from soil and sediments were dominated by species belonging to Pseudomonas and Acinetobacter genera, while in the seawater-derived consortia Dietzia, Fusobacterium and Mycoplana emerged as dominant genera. We identified a number of species whose relative abundances bloomed from small to high percentages: Dietzia daqingensis in the seawater microcosms, and three OTUs classified as Acinetobacter venetianus in all two soils and sediment derived microcosms. Functional analyses on degrading genes were conducted by comparing PCR results of the degrading genes alkB, ndoB, cat23, xylA and nidA1 with inferences obtained by PICRUSt analysis of 16S amplicon data: the two data sets were partly in agreement and suggest a relationship between the catabolic genes detected and the rate of biodegradation obtained. The work provides detailed insights about the modulation of bacterial communities involved in petroleum biodegradation and can provide useful information for in situ bioremediation of oil-related pollution.  相似文献   
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