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排序方式: 共有2754条查询结果,搜索用时 15 毫秒
1.
《Vaccine》2022,40(7):1001-1009
Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases. 相似文献
2.
《Vaccine》2019,37(22):2952-2959
CD8+ T cells are known to control infections, but their role in preventing latent infection from establishing has not been thoroughly investigated.We hypothesized that a potent CD8+ T cell response patrolling the mucosal viral entry points could kill the first infected cells and thereby abrogate the infection before latency is established.To investigate this, replication deficient adenovirus serotype 5 vectors encoding murine γ-herpesvirus-68 CD8+ T cell epitopes linked to the T cell adjuvant Invariant chain, were developed. We show that intranasal vaccination of mice reduces the risk of establishment of latent infection from multiple intranasal ID50 challenges with murine γ-herpesvirus-68 by 81% per exposure at 14 days post vaccination. Protection waned over time, but immune responses were extended by heterologous prime-boost vaccination applied simultaneously intramuscularly and intranasally, and animals vaccinated 66 days prior to challenge showed a strong trend of long-term protection.Our data provides evidence that CD8+ T cells are able to protect against establishment of latent infection. Although the protective efficacy is difficult to maintain over time, this proof-of-concept study suggests a role for a CD8+ T cell arm in future vaccine strategies against latent human viral infections caused by pathogens such as HIV and multiple herpes virus. 相似文献
3.
Danghui XuJianxin YaoYiwen ZhangNan XiaoPeng PengZhanfeng LiZhiyao PanZhifeng Yao 《Asian Pacific journal of cancer prevention》2020,21(4):911-917
Objective: The study was undertaken to investigate the effects of polyethyleneimine (PEI)-mediated adenovirus 5 early region 1A (E1A) on radiosensitivity of human hepatic carcinoma cell in vitro and to disclosure the underlying mechanism. Materials and Methods: Human hepatic carcinoma SMMC-7721 cell line was transfected with E1A gene using PEI vector. Untransfected cells (SMMC-7721 group), cells transfected with blank-vector (SMMC-7721-vect group), and cells transfected with E1A gene (SMMC-7721-E1A group) were treated with 6 MV X-ray irradiation at doses of 0, 1, 2, 4, 8 and Gy, respectively. Radiosensitivity was determined by MTT assay and quantified by calculating the cell survival rate. Cell-cycle distribution and apotosis rate were monitored by flow cytometry. Results: The survival rate of SMMC-7721-E1A was significantly lower than that of SMMC-7721 cell. Apoptosis rate of SMMC-7721-E1A group was significantly higher than that of SMMC-7721group (P<0.01).The ratio of S stage in cell cycle of SMMC-7721-E1A was significantly lower than that in SMMC-7721 cell. The ratio of G2/M stage in cell cycle of SMMC-7721-E1A was significantly higher than that in SMMC-7721 cell (P<0.01). Conclusion: PEI could transfect E1A gene into hepatic carcinoma cells PEI-mediated E1A could effectively enhance radiosensitivity of hepatic carcinoma cells which may be related to its effects on apoptosis promoting leading to S phase suppression and G2/M phase arrest. 相似文献
4.
Phonphimon Wongthida Matthew R Schuelke Christopher B Driscoll Timothy Kottke Jill M Thompson Jason Tonne Cathy Stone Amanda L Huff Cynthia Wetmore James A Davies Alan L Parker Laura Evgin Richard G Vile 《Neuro-oncology》2020,22(12):1757
BackgroundDiffuse midline glioma, formerly DIPG (diffuse intrinsic pontine glioma), is the deadliest pediatric brainstem tumor with median survival of less than one year. Here, we investigated (i) whether direct delivery of adenovirus-expressing cluster of differentiation (CD)40 ligand (Ad-CD40L) to brainstem tumors would induce immune-mediated tumor clearance and (ii) if so, whether therapy would be associated with a manageable toxicity due to immune-mediated inflammation in the brainstem.MethodsSyngeneic gliomas in the brainstems of immunocompetent mice were treated with Ad-CD40L and survival, toxicity, and immune profiles determined. A clinically translatable vector, whose replication would be tightly restricted to tumor cells, rAd-Δ24-CD40L, was tested in human patient–derived diffuse midline gliomas and immunocompetent models.ResultsExpression of Ad-CD40L restricted to brainstem gliomas by pre-infection induced complete rejection, associated with immune cell infiltration, of which CD4+ T cells were critical for therapy. Direct intratumoral injection of Ad-CD40L into established brainstem tumors improved survival and induced some complete cures but with some acute toxicity. RNA-sequencing analysis showed that Ad-CD40L therapy induced neuroinflammatory immune responses associated with interleukin (IL)-6, IL-1β, and tumor necrosis factor α. Therefore, to generate a vector whose replication, and transgene expression, would be tightly restricted to tumor cells, we constructed rAd-Δ24-CD40L, the backbone of which has already entered clinical trials for diffuse midline gliomas. Direct intratumoral injection of rAd-Δ24-CD40L, with systemic blockade of IL-6 and IL-1β, generated significant numbers of cures with readily manageable toxicity.ConclusionsVirus-mediated delivery of CD40L has the potential to be effective in treating diffuse midline gliomas without obligatory neuroinflammation-associated toxicity. 相似文献
5.
Decorin‐expressing adenovirus decreases collagen synthesis and upregulates MMP expression in keloid fibroblasts and keloid spheroids 下载免费PDF全文
Won Jai Lee Hyo Min Ahn Hyun Roh Youjin Na Il‐Kyu Choi Ju Hee Lee Yong Oock Kim Dae Hyun Lew Chae‐Ok Yun 《Experimental dermatology》2015,24(8):591-597
Decorin is a natural transforming growth factor‐β1 (TGF‐β1) antagonist. Reduced decorin synthesis is associated with dermal scarring, and increased decorin expression appears to reduce scar tissue formation. To investigate the therapeutic potential of decorin for keloids, human dermal fibroblasts (HDFs) and keloid‐derived fibroblasts (KFs) were transduced with decorin‐expressing adenovirus (dE1‐RGD/GFP/DCN), and we examined the therapeutic potential of decorin‐expressing Ad for treating pathologic skin fibrosis. Decorin expression was examined by immunofluorescence assay on keloid tissues. HDFs and KFs were transduced with dE1‐RGD/GFP/DCN or control virus, and protein levels of decorin, epidermal growth factor receptor (EGFR) and secreted TGF‐β1 were assessed by Western blotting and ELISA. And type I and III collagen, and matrix metalloproteinase‐1 (MMP‐1) and matrix metalloproteinase‐3 (MMP‐3) mRNA levels were measured by real‐time RT‐PCR. Additionally, we immunohistochemically investigated the expression levels of the major extracellular matrix (ECM) proteins in keloid spheroids transduced with dE1‐RGD/GFP/DCN. Lower decorin expression was observed in the keloid region compared to adjacent normal tissues. After treatment with dE1‐RGD/GFP/DCN, secreted TGF‐β1 and EGFR protein expressions were decreased in TGF‐β1‐treated HDFs and KFs. Also, type I and III collagen mRNA levels were decreased, and the expression of MMP‐1 and MMP‐3 mRNA was strongly upregulated. In addition, the expression of type I and III collagen, fibronectin and elastin was significantly reduced in dE1‐RGD/GFP/DCN‐transduced keloid spheroids. These results support the utility of decorin‐expressing adenovirus to reduce collagen synthesis in KFs and keloid spheroid, which may be highly beneficial in treating keloids. 相似文献
6.
Viral infection in placenta relevant cells – a morphological and immunohistochemical cell culture study 下载免费PDF全文
Gitta Turowski Halvor Rollag Borghild Roald 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(1):60-64
Viral infections in pregnancy are known to cause fetal malformation, growth restriction, and even fetal death. Macroscopic placental examination usually shows slight and unspecific changes. Histology may show secondary, non‐specific tissue reaction, i.e. villitis with lymphocytic invasion. Primary specific morphology characteristics are known for some virus, like cytomegalovirus, parvovirus, and herpes simplex, however many viral infections show non‐specific changes. Placenta relevant cells as human first trimester trophoblasts HTR8/SVneo, primary human umbilical vein endothelial cells (HUVEC), and primary human embryonic fibroblasts were examined following infection with commonly occurring virus like adenovirus and enterovirus. Morphology in routine stained sections and virus‐specific immunostains were studied 4, 8, 24, 48, 72 h after infection. Nuclear enlargement was seen in the infected cells. A specific diagnosis of adenovirus or enterovirus infection, however, was not possible without specific immunostains. 相似文献
7.
8.
人腺病毒(HAdV)是一种无包膜双链DNA病毒,是引起6月龄至2岁婴幼儿重症肺炎最常见的病毒病原体。2019年以来,中国多个地区发现多例重症HAdV肺炎患儿,对儿童生命健康造成严重威胁。该文就HAdV的基因型、流行趋势、疾病严重度、致病机制以及儿童HAdV肺炎的早期诊断和干预、治疗方法等方面进行介绍。 相似文献
9.
《Vaccine》2021,39(26):3498-3508
Adenovirus infections are a major cause of epidemic keratoconjunctivitis (EKC), which can lead to corneal subepithelial infiltrates and multifocal corneal opacity. In the current study, we investigated the use of an E1/E3-deleted adenovirus serotype 5 (Ad5) vector as a vaccine administered intramuscularly (IM) or intranasally (IN) against subsequent challenges with a luciferase-expressing Ad5 (Ad5-Luci) vector via eyedrop. We evaluated the adaptive immune response to Ad5 vector vaccination and confirmed a robust polyfunctional CD8 T cell response in splenic cells. Neutralizing Ad5 antibodies were also measured in the sera of vaccinated mice as well as Ad5 antibody in the eye wash solutions. Upon challenge with Ad5-Luci vector 8 weeks post the primary immunization, transduction was significantly reduced by > 70% in the vaccinated mice, which was slightly better in IM- vs. that in IN-vaccinated animals. Resistance to subsequent challenge was observed 10 months post primary IM vaccination, with sustained reduction up to 60% in the Ad5-Luci vector transduction. Passive immunization of naive mice with antisera from IM to vaccinated mice subsequently challenged with the Ad5-Luci vector resulted in approximately 40% loss in transduction efficiency. Furthermore, the mice that received IM immunization with or without CD8 T cell depletion showed > 40% and 70% reductions, respectively, in Ad8 genomic copies after Ad8 topical challenge. We conclude that Ad-vector vaccination successfully induced an adaptive immune response that prevented subsequent Ad transduction in the cornea and conjunctiva-associated tissues in a mouse model of adenovirus keratoconjunctivitis, and that both cellular and humoral immunity play an important role in preventing Ad transduction. 相似文献
10.