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71.
CD4(+) T-cells from gut-associated lymphoid tissues (GALT) are major targets for HIV-1 infection. Recruitment of excess effector CD8(+) T-cells in the proximity of target cells is critical for the control of viral replication. Here, we investigated the colocalization potential of HIV-specific CD8(+) and CD4(+) T-cells into the GALT and explored the role of retinoic acid (RA) in regulating this process in a cohort of HIV-infected subjects with slow disease progression. The expression of the gut-homing molecules integrin β7, CCR6, and CXCR3 was identified as a "signature" for HIV-specific but not CMV-specific CD4(+) T-cells thus providing a new explanation for their enhanced permissiveness to infection in vivo. HIV-specific CD8(+) T-cells also expressed high levels of integrin β7 and CXCR3; however CCR6 was detected at superior levels on HIV-specific CD4(+) versus CD8(+) T-cells. All trans RA (ATRA) upregulated the expression of integrin β7 but not CCR6 on HIV-specific T-cells. Together, these results suggest that HIV-specific CD8(+) T-cells may colocalize in excess with CD4(+) T-cells into the GALT via integrin β7 and CXCR3, but not via CCR6. Considering our previous findings that CCR6(+)CD4(+) T-cells are major cellular targets for HIV-DNA integration in vivo, a limited ability of CD8(+) T-cells to migrate in the vicinity of CCR6(+)CD4(+) T-cells may facilitate HIV replication and dissemination at mucosal sites.  相似文献   
72.
In recent years, RNA interference has been exploited as a tool for investigating gene function in plants. We tested the potential of double-stranded RNA interference technology for silencing a transgene in the actinorhizal tree Allocasuarina verticillata. The approach was undertaken using stably transformed shoots expressing the beta-glucuronidase (GUS) gene under the control of the constitutive promoter 35S; the shoots were further transformed with the Agrobacterium rhizogenes A4RS containing hairpin RNA (hpRNA) directed toward the GUS gene, and driven by the 35S promoter. The silencing and control vectors contained the reporter gene of the green fluorescent protein (GFP), thus allowing a screening of GUS-silenced composite plantlets for autofluorescence. With this rapid procedure, histochemical data established that the reporter gene was strongly silenced in both fluorescent roots and actinorhizal nodules. Fluorometric data further established that the level of GUS silencing was usually greater than 90% in the hairy roots containing the hairpin GUS sequences. We found that the silencing process of the reporter gene did not spread to the aerial part of the composite A. verticillata plants. Real-time quantitative polymerase chain reaction showed that GUS mRNAs were substantially reduced in roots and, thereby, confirmed the knock-down of the GUS transgene in the GFP(+) hairy roots. The approach described here will provide a versatile tool for the rapid assessment of symbiotically related host genes in actinorhizal plants of the Casuarinaceae family.  相似文献   
73.
Our case concerns 66-year-old female with a multiple unusual locations of hydatid cysts including bladder, psoas muscle and liver. Coexistence of hydatid cysts in these localizations has not been previously reported. The diagnosis of vesical hydatid cyst was facilitated by the coexistence of other echinococcosis locations. Treatment consists of the excision of the cysts in the same session without any postoperative anthelmintic drugs. In a two-year follow-up no recurrence has occurred.  相似文献   
74.
Motile Sperm Organelle Morphology Examination (MSOME) constitutes a real improvement in ART management and outcome, as it allows detection of specific sperm anomalies on living cells, which cannot be detected by routine analysis. MSOME applied to the selection of sperm injected into the oocyte is called IMSI (Intracytoplasmic Morphologically Selected sperm Injection) and is associated with a considerable improvement of implantation, clinical pregnancy and delivery rates. A high-power microscope (X 2,000 to X 10,000) and video enhancement system are necessary and technical limitations are related to cryptozoospermia and/or severe teratozoospermia. Compared to routine sperm morphology assessment, MSOME allows the detection of subtle cephalic anomalies, such as vacuoles. These vacuoles seem to have a deleterious effect on fertilization and embryo developmentin vitro. These observations have led to a detailed classification of anomalies and this morphological diagnosis on living sperm demonstrates that most sperm selected for conventional ICSI at X 400 are actually abnormal on MSOME at X 6,000 or more. In addition to the very good results obtained in IMSI, this new approach opens up interesting prospects concerning the relationship between the phenotype of the injected sperm and its fertilization capacity and embryo development. In terms of diagnosis, MSOME could be used to select and study homogeneous groups of normal sperm or homogeneous groups of sperm exhibiting the same well defined anomaly. Such studies, associated with fine analysis of injected sperm and follow-up of each oocyte and each embryo, should provide more information about the relationship between sperm structure and function and should help to define the relevant indications for IMSI and the choice of spermatozoa to be injected.  相似文献   
75.
The cardiovascular and sympathetic effects of TRH in discrete cardiovascular-related brain nuclei were studied. Microinjections of TRH were made into the nucleus preopticus medialis (POM) of conscious rats and the nucleus tractus solitarius (NTS) of pentobarbitone-anesthetized, artificially respired rats. POM injections (1 μl, 0.8–80 nM) elicited dose dependent pressor and tachycardic responses which were accompanied by increased levels of norepinephrine (NE) and epinephrine (EPI) in the plasma. These pressor/tachycardic effects of TRH were also elicited in adrenal demedullated (ADM-x) rats, but completely abolished in ADM-x rats pretreated with bretylium (30 mg/kg, IA). NTS injections (0.1 μl, 30 and 150 nM) had a short depressor effect on blood pressure (BP) and a delayed increase in heart rate (HR). From these findings we suggest that the POM, a central nucleus in the AV3V region, may be an important forebrain site for autonomic regulation by TRH, mediated through the sympathetic nervous system.  相似文献   
76.
In order to assess the potential role of mu (μ) and delta (δ) opiate receptors in the central regulation of the cardiovascular and respiratory systems, the cardiovascular and respiratory effects of the relatively selective μ-opioid agonist D-Ala2, MePhe4, Gly-ol5 enkephalin (DAGO) and relatively selective δ-agonist D-Ala2-D-Leu5 enkephalin (DADL) were compared following microinjection of these compounds into the nucleus tractus solitarius of pentobarbital-anesthetized rats. Both opioid agonists produced dose dependent increases in systolic and diastolic blood pressure as well as heart rate; but DAGO was nearly ten times more potent in eliciting these changes. Respiratory rate was increased by DADL and by lower doses of DAGO, but was depressed by higher doses of DAGO. Tidal volume was depressed by both peptides. These data support the concept that the cardiovascular pressor responses and tachycardia as well as the respiratory effects of opioids in the rat NTS are mediated by μ receptors.  相似文献   
77.
The leaf-mining hispidPromecotheca cumingi Baly, was first recorded as a pest on coconut in Sri lanka in October 1970. Its possible mode of entry and spread from the point of first occurrence are discussed. An account is given of the life-cycle, rate of multiplication, host plants and damage under Sri Lanka conditions. The spectacular success achieved in controlling the pest, which was spread over about 8,000 hectares, using the biological method, the techniques adopted for breeding and release of exotic parasites and the follow-up surveys to ascertain activity of the introduced parasites are discussed in detail. A brief account of the cost/benefit analysis is also given.  相似文献   
78.
Summary Strains ofEscherichia coli K12 that contain a deletion of the adenyl cyclase gene (cya), required for the synthesis of cyclic adenosine-3; 5 monophosphate (cAMP), grow on galactose-containing minimal medium. A mutant was isolated that grows on this medium only if cAMP is added. The mutation (designatedgalP20) is linked to thegal operon region as determined by both generalized transduction with bacteriophage P1 and specialized transduction with bacteriophage . Studies withgalP20 cya strains as well asgal (deletions of thegal operon)cya strains indicate that synthesis of the physiologically important transport mechanism for galactose (galactose permease) requires either cAMP or a function missing from both thegal strains and thegalP20 strain.  相似文献   
79.
The present study aim was to valorize the treated waste water as source of fertilizers for vegetables seed production and to assess the eventual bacteriological contamination risks of soil, plant and phreatic ground water table. The bacteriological analysis of drained water did not reveal any fecal coliforms vertical migration in depth and a low fecal contamination (thermotolerant coliforms) is limited to the levels of superficial horizons. The seed produced by using waste water showed a slightly fecal contamination which disappeared following treatment with a (5% chloride solution. The treated waste water improve the onion seeds production per hectare in spite of the increases of the phytopathogenic hazards.  相似文献   
80.
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