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91.
92.
Background Traumatic spinal cord injury leads to direct myelin and axonal damage and leads to the recruitment of inflammatory cells to site of injury. Although rodent models have provided the greatest insight into the genesis of traumatic spinal cord injury (TSCI), recent studies have attempted to develop an appropriate non‐human primate model. Methods We explored TSCI in a cynomolgus macaque model using a balloon catheter to mimic external trauma to further evaluate the underlying mechanisms of acute TSCI. Results Following 1 hour of spinal cord trauma, there were focal areas of hemorrhage and necrosis at the site of trauma. Additionally, there was a marked increased expression of macrophage‐related protein 8, MMP9, IBA‐1, and inducible nitric oxide synthase in macrophages and microglia at the site of injury. Conclusions This data indicate that acute TSCI in the cynomolgus macaque is an appropriate model and that the earliest immunohistochemical changes noted are within macrophage and microglia populations.  相似文献   
93.

Background

Periodic spacing of A-tracts (short runs of A or T) with the DNA helical period of ~10?C11?bp is characteristic of intrinsically bent DNA. In eukaryotes, the DNA bending is related to chromatin structure and nucleosome positioning. However, the physiological role of strong sequence periodicity detected in many prokaryotic genomes is not clear.

Results

We developed measures of intensity and persistency of DNA curvature-related sequence periodicity and applied them to prokaryotic chromosomes and phages. The results indicate that strong periodic signals present in chromosomes are generally absent in phage genomes. Moreover, chromosomes containing prophages are less likely to possess a persistent periodic signal than chromosomes with no prophages.

Conclusions

Absence of DNA curvature-related sequence periodicity in phages could arise from constraints associated with DNA packaging in the viral capsid. Lack of prophages in chromosomes with persistent periodic signal suggests that the sequence periodicity and concomitant DNA curvature could play a role in protecting the chromosomes from integration of phage DNA.  相似文献   
94.
Background  Pediatric hepatic angiosarcoma is a rare condition in children with poor prognosis. Microscopically this neoplasm has a particular 'Kaposi-form' arrangement. Hemangiosarcoma in non-human primates is a rare finding.
Methods  Gross and microscopic examination of a 3-year-old rhesus were performed. Immunohistochemistry was used to characterize the hepatic hemangiosarcoma.
Results  The gross necropsy revealed hemoabdomen and a 4 × 3 × 3 cm mass in the liver with multiple smaller masses throughout the hepatic parenchyma. Histopathology confirmed a poorly differentiated hemangiosarcoma. Other organs submitted were free of metastases.
Conclusions  Hemangiosarcoma in non-human primates has been rarely reported. Diagnosis was confirmed by expression of endothelial-specific markers CD31 and vWF by immunohistochemistry. Due to the young age of this monkey and the particular solid pattern throughout the mass this neoplasm resembles pediatric hepatic angiosarcoma in humans.  相似文献   
95.

Background

Previous studies have shown that disruption of GABA signaling in mice via mutations in the Gad1, Gabrb3 or Viaat genes leads to the development of non-neural developmental defects such as cleft palate. Studies of the Gabrb3 and Gad1 mutant mice have suggested that GABA function could be required either in the central nervous system or in the palate itself for normal palatogenesis.

Methodology/Principal Findings

To further examine the role of GABA signaling in palatogenesis we used three independent experimental approaches to test whether Gad1 or Viaat function is required in the fetal CNS for normal palate development. We used oral explant cultures to demonstrate that the Gad1 and Viaat mutant palates were able to undergo palatogenesis in culture, suggesting that there is no defect in the palate tissue itself in these mice. In a second series of experiments we found that the GABAA receptor agonist muscimol could rescue the cleft palate phenotype in Gad1 and Viaat mutant embryos. This suggested that normal multimeric GABAA receptors in the CNS were necessary for normal palatogenesis. In addition, we showed that CNS-specific inactivation of Gad1 was sufficient to disrupt palate development.

Conclusions/Significance

Our results are consistent with a role for Gad1 and Viaat in the central nervous system for normal development of the palate. We suggest that the alterations in GABA signaling lead to non-neural defects such as cleft palate as a secondary effect due to alterations in or elimination of fetal movements.  相似文献   
96.
97.
A multivariate morphometric study of the genus Pyrus in south-west Europe and North Africa shows that five species may be recognized in the area: P. bourgaeana Decne., P. communis L., P. cordata Dew., P. spinosa Forssk, and P. nivalis Jacq. Some valuable characters for identification of these species are proposed. In particular the width of fruit peduncle, petal size, leaf width and petiole length served to discriminate the taxa. Several names such as P. gharbiona Trab., P. cossonii Rehder (|M= P. longipes Balansa ex Coss. & Durieu) and P. boisseriana Buhse, are regarded as synonyms of P. cordata , while P. marnormis Trab. of P. bourgaeana. Consequently a check-list and a key to these species are provided.  相似文献   
98.
With the emergence of the AIDS epidemic over the last 2 decades and the more recent identification of Kaposi sarcoma-associated herpesvirus (KSHV, Human herpesvirus 8), the genera of rhadinoviruses have gained importance as a family of viruses with oncogenic potential. First recognized in New World primates more than 30 y ago, the rhadinoviruses Saimiriine herpesvirus 2 and Ateline herpesvirus 2 have well-described transforming capabilities. Recently several new species-specific rhadinoviruses of Old World primates have been described, including retroperitoneal fibromatosis herpesvirus and rhesus rhadinovirus (Cercopithecine herpesvirus 17). Molecular analysis of these viruses has elucidated several functionally conserved genes and properties shared with KSHV involved in cellular proliferation, transformation, and immune evasion that facilitate the oncogenic potential of these viruses. This review examines the comparative pathobiology of KSHV, discusses the role of macaque rhadinoviruses as models of human disease, and outlines the derivation of specific pathogen-free animals.Abbreviations: CCL, cellular chemokine ligand; IRF, interferon regulatory factors; KSHV, Kaposi sarcoma-associated herpesvirus; LANA, latent nuclear antigen; MCD, multicentric Castleman disease; MCP1, monocyte chemotactic protein 1; miRNA, microRNA; ORF, open reading frame; PEL, primary effusion lymphoma; RFHV, retroperitoneal fibromatosis herpesvirus; RVV, rhesus rhadinovirus; SaHV2, Saimiriine herpesvirus 2; SPF, specific pathogen-free; SRV2, simian retrovirus type 2; THBS1, thrombospondinMembers of the herpesviridae are enveloped DNA viral agents that can infect a variety of host species, resulting in lifelong infection. The family is divided into Alphaherpesvirinae, Betaherpesvirinae, and Gammaherpesvirinae, according to biologic behavior and phylogenetic relationship. As a group, synthesis of viral DNA occurs in the nucleus, and production of infectious virions is associated with destruction of the cell. Herpesviruses have large complex genomes and often have acquired host genes that allow these viruses to modulate and persist in the face of host immune responses.25,71 This condition (termed ‘latency’) is characteristic of all herpesviral infections of the natural host. Although most members of the herpesviridae are of relatively low virulence in their respective hosts, some lack strict host specificity, and cross-species transmission to an inadvertent host can be associated with severe and fatal disease.The gammaherpesvirinae subfamily is characterized by in vitro and in vivo infection of lymphoblastoid cells and is further divided into the lymphocryptovirus (γ1 herpesviruses) and rhadinovirus (γ2 herpesviruses) genera. Rhadinoviruses have taken on increased importance with the identification of the novel Kaposi sarcoma-associated herpesvirus (KSHV, Human herpesvirus 8) in association with Kaposi sarcoma, an inflammatory and neoplastic condition seen in many HIV-infected patients with AIDS.20,22 Until the recognition of KSHV more than a decade ago, rhadinovirus infection of primates was thought to be restricted to the New World primate lineages, but subsequent investigation revealed a number of novel species-specific viruses in a variety of Old World primates (28 As discussed later, based largely on phylogenetic analysis, it is now believed that the rhadinoviruses are subdivided into 2 distinct groupings (rhadinovirus [RV] 1 and 2).77 This review will examine 2 recently recognized rhadinoviruses of macaques (retroperitoneal fibromatosis virus [RFHV] and rhesus rhadinovirus [RRV, Cercopethecine herpesvirus 17]), focusing on their comparative pathobiology with KSHV, their impact on naturally occurring disease entities, and their roles as animal models of human disease.

Table 1.

Nomenclature of primate rhadinoviruses (RV)
GroupAbbreviationOfficial designationaAlternative designationHostVirus isolatedGenomic sequence available
RV1
HHV8Human herpesvirus 8KSHVHomo sapiensyesyes
RV1mmunot availableRFHVmmuMacaca mulattanono
RV1mnenot availableRFHVmneMacaca nemestrinanono
RV1pannot availablePtRV1a andPan troglodytesnono
PtRV1b
RV1gornot availableGorRV1Gorilla gorillanono
RV1agmnot availableChRV1Chlorocebus aethiopsnono
RV2
HVSSaimirine herpesvirus 2 (SaHV2)noneS. sciureusyesyes
HVAAteline herpesvirus 2 (AtHV2)noneAteles geoffroyiyesyes
RV2mmuCercopethecine herpesvirus 17 (CeHV17)RRVMacaca mulattayesyes
RV2mnenot availablePRVMacaca nemestrinayesno
RV2pannot availablePtRV2Pan troglodytesnono
RV2agmnot availableChRV2Chlorocebus aethiopsnono
RV2pannot availablePapRV2Pan anubisnono
Open in a separate windowaFrom the International Committee on Taxonomy of Viruses.  相似文献   
99.
Destruction of cartilage and bone are hallmarks of human rheumatoid arthritis (RA), and controlling these erosive processes is the most challenging objective in the treatment of RA. Systemic interleukin-4 treatment of established murine collagen-induced arthritis suppressed disease activity and protected against cartilage and bone destruction. Reduced cartilage pathology was confirmed by both decreased serum cartilage oligomeric matrix protein (COMP) and histological examination. In addition, radiological analysis revealed that bone destruction was also partially prevented. Improved suppression of joint swelling was achieved when interleukin-4 treatment was combined with low-dose prednisolone treatment. Interestingly, synergistic reduction of both serum COMP and inflammatory parameters was noted when low-dose interleukin-4 was combined with prednisolone. Systemic treatment with interleukin-4 appeared to be a protective therapy for cartilage and bone in arthritis, and in combination with prednisolone at low dosages may offer an alternative therapy in RA.  相似文献   
100.
We recently described a coreceptor switch in rapid progressor (RP) R5 simian-human immunodeficiency virus SF162P3N (SHIV(SF162P3N))-infected rhesus macaques that had high virus replication and undetectable or weak and transient antiviral antibody response (S. H. Ho et al., J. Virol. 81:8621-8633, 2007; S. H. Ho, N. Trunova, A. Gettie, J. Blanchard, and C. Cheng-Mayer, J. Virol. 82:5653-5656, 2008; and W. Ren et al., J. Virol. 84:340-351, 2010). The lack of antibody selective pressure, together with the observation that the emerging X4 variants were neutralization sensitive, suggested that the absence or weakening of the virus-specific humoral immune response could be an environmental factor fostering coreceptor switching in vivo. To test this possibility, we treated four macaques with 50 mg/kg of body weight of the anti-CD20 antibody rituximab every 2 to 3 weeks starting from the week prior to intravenous infection with SHIV(SF162P3N) for a total of six infusions. Rituximab treatment successfully depleted peripheral and lymphoid CD20(+) cells for up to 25 weeks according to flow cytometry and immunohistochemical staining, with partial to full recovery in two of the four treated monkeys thereafter. Three of the four treated macaques failed to mount a detectable anti-SHIV antibody response, while the response was delayed in the remaining animal. The three seronegative macaques progressed to disease, but in none of them could the presence of X4 variants be demonstrated by V3 sequence and tropism analyses. Furthermore, viruses did not evolve early in these diseased macaques to be more soluble CD4 sensitive. These results demonstrate that the absence or diminution of humoral immune responses by itself is insufficient to drive the R5-to-X4 switch and the neutralization susceptibility of the evolving viruses.  相似文献   
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