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11.

Background

Access to the information concerning blood safety is essential for managing problems and overcoming the challenges that are faced in any given region. Information on the availability and safety of blood in countries of the Economic Cooperation Organisation (ECO) is largely lacking. To address this problem, the Iranian Blood Transfusion Organisation, in collaboration with other ECO member states, initiated a research project in 2009 to collect, analyse and compare statistics on blood safety in the region.

Materials and methods

A modified and summarised version of the Global Database on Blood Safety (GDBS) questionnaire was used to collect data. The questionnaire was sent to all ten countries in the ECO region. The heads of the national transfusion services or focal points were requested to complete the form. Related literature and websites were also reviewed.

Results

Only three countries (Afghanistan, Iran and Turkey) completed the questionnaire, while other countries provided their available data on some parts of the questionnaire. The number of donations per year varied from 5 to 27/1,000 population. The rate of donors positive for human immunodeficiency virus ranged from 0.003% to 0.2%. The rate of donors positive for hepatitis C virus antibody varied from 0.05% to 3.9% while that of hepatitis B virus surface antigen ranged from 0.15% to 3.91% respectively.

Discussion

There is very clear diversity in blood transfusion services among ECO member states. Most countries in the region do not have a data-recording system. It is generally estimated that the need for blood is much higher than the supply in this region. Deficiencies in donor screening and a high prevalence of transfusion-transmitted infections are other important challenges.  相似文献   
12.

Aims/hypothesis

Adult beta cells have a diminished ability to proliferate. Phosphatase and tensin homologue (PTEN) is a lipid phosphatase that antagonises the function of the mitogenic phosphatidylinositol 3-kinase (PI3K) pathway. The objective of this study was to understand the role of PTEN and PI3K signalling in the maintenance of beta cells postnatally.

Methods

We developed a Pten lox/lox; Rosa26 lacZ; RIP-CreER + model that permitted us to induce Pten deletion by treatment with tamoxifen in mature animals. We evaluated islet mass and function as well as beta cell proliferation in 3- and 12-month-old mice treated with tamoxifen (Pten deleted) vs mice treated with vehicle (Pten control).

Results

Deletion of Pten in juvenile (3-month-old) beta cells significantly induced their proliferation and increased islet mass. The expansion of islet mass occurred concomitantly with the enhanced ability of the Pten-deleted mice to maintain euglycaemia in response to streptozotocin treatment. In older mice (>12 months of age), deletion of Pten similarly increased islet mass and beta cell proliferation. This novel finding suggests that PTEN-regulated mechanisms may override the age-onset diminished ability of beta cells to respond to mitogenic stimulation. We also found that proteins regulating G1/S cell-cycle transition, such as cyclin D1, cyclin D2, p27 and p16, were altered when PTEN was lost, suggesting that they may play a role in PTEN/PI3K-regulated beta cell proliferation in adult tissue.

Conclusions/interpretation

The signals regulated by the PTEN/PI3K pathway are important for postnatal maintenance of beta cells and regulation of their proliferation in adult tissues.  相似文献   
13.
    
Phosphorus-containing compounds are one of the most important classes of organic compounds, which have wide applications in organic chemistry, medicinal chemistry, agricultural chemistry, and materials chemistry. In particular, organophosphorus compounds bearing a P(O)–C bond have attracted significant attention in recent decades due to their widespread biological and pharmacological activities. In this review, we will highlight the most important developments in the construction of P(O)–C bonds through decarboxylative C–P cross-coupling reactions. The literature has been surveyed from 2011 to May 2018.

Phosphorus-containing compounds are one of the most important classes of organic compounds, which have wide applications in organic chemistry, medicinal chemistry, agricultural chemistry, and materials chemistry.  相似文献   
14.
Pericardial patch has been used to repair cardiac defects; however, its strength as an aortoplasty patch to tolerate systemic pressure is a matter of debate. We report an aneurysmal dilatation of pericardial patch in aortoplasty. Our patient was a 56-year-old female known case of rheumatic heart disease that underwent redoes mitral and aortic valve replacements along with Manouguian aortoplasty at the age of 44?years old. After 2?months, she was readmitted with a diagnosis of endocarditis. Echocardiography revealed a small cavity in the posterior wall of the aorta. She responded to medical therapy and discharged in a good condition. Twelve years later, she was scheduled to undergo reoperation due to a severe paraprosthetic aortic valve leakage and a pericardial patch aneurysm. The leaking prosthetic aortic valve was explanted and the aneurysmal tissue was replaced with a polyethylene terephthalate patch.  相似文献   
15.
16.
Rapid and effective diagnosis of brucellosis is a challenge for clinicians. Even when diagnosis is on time and therapy is initiated, meticulous follow-up appointments are crucial for ensuring the efficacy of the treatment. Due to shortcomings of serological methods, molecular diagnosis, especially real-time PCR, is becoming a main approach in laboratory diagnostics. Thus, the development of efficient procedures and standardization of the PCR tests will have a great impact on the precise detection and quantification of bacterial DNA loads, which is valuable for the medical management of brucellosis patients. We developed a new TaqMan real-time PCR directed to bcsp31, a shared gene of the brucellae. The bcsp31 gene fragment was cloned into pJET1.2. Recombinant pJET1.2-bcsp31 was linearized by HindIII digestion, and the product was used for the preparation of a standard curve. A panel of Brucella spp. and non-Brucella pathogens was tested. No bacterial genomes other than those of the brucellae were detected. According to the results, specificity of the method was 100%. In a clinical assessment, the positive-control group comprised 37 patients with microbiologically confirmed brucellosis, and 25 healthy individuals served as the negative-control group. By the end of the treatment period, there was a significant decrease in the DNA load of the 37 brucellosis patients, which persisted for the 4 weeks of monitoring after treatment, suggesting that our proposed method is an efficient monitoring tool. Serum samples prior to any treatment were collected from the 25 serologically suspicious patients and assessed by our method; 72% of these patients tested positive for brucellosis.  相似文献   
17.
Summary. Complete nucleotide sequence of the Iranian strain of tomato yellow leaf curl virus (TYLCV-IR) was determined and compared with some begomoviruses. The complete sequence of TYLCV-IR clustered together with TYLCV and TYLCV-MId from Israel. A similar relationship holds when the deduced amino acid sequences of V1, V2, C2 and C3 and nucleotide sequences of IR, and RIR were compared. In contrast, phylogenetic analyses of amino acid sequences of C4, C1, and nucleotide sequences of LIR revealed that TYLCV-IR clustered with TLCIRV and two Indian species: ToLCBV- [Ban4], and ToLCKV. The phylogenetic analyses, Recombination Detection Program analyses, and sequence alignment survey provided evidence of the occurrence of recombination between an Israeli TYLCV-MId, as major parent, and TLCIRV, as minor parent. In this recombination event, a region (from nt 2149 to 2766) of TYLCV-MId genome were replaced with corresponding genome sequences of TLCIRV (RDP P-value = 5.976 × 10–72), which include LIR, C4, and N-terminal of C1. Infectivity of the cloned TYLCV-IR genome was demonstrated by successful agroinoculation of tomato (Lycopersicon esculentum) and other plant species. The disease was transmitted by the natural vector Bemisia tabaci from agroinoculated plants to test plants, reproducing in this way the full biological cycle and proving that the genome of TYLCV-IR consists of only one circular single-stranded DNA molecule.  相似文献   
18.
Various types of physical and physiological stress in animals have been shown to affect their humoral and cell-mediated immune responses. The present study was designed to investigate the possible influence of acute pain on the immune system. BALB/c mice were exposed to an increasing number of heat shocks using a Tail Flick apparatus; an equal number of control mice received no shock treatments. After each of the regimens was completed, the spleen of each mouse was recovered and various cell populations isolated to assess: the proliferative response to phytohemagglutinin by lymphocytes; cytotoxic activities of natural killer (NK) cells; and, the production of select important cytokines by splenic lymphocytes. The results indicated that NK cell activity and proliferation of lymphocytes were significantly (p < 0.001) increased due to the shock regimens after only a single day's rounds of stimulation (i.e., 3 rounds of ≈12 equally time-spaced shocks/hr with 30–45 min gap between rounds). After 2 and 3 days' rounds of stimulations, no significant changes were detected in the proliferative response of isolated lymphocytes; conversely, the activity of NK cells remained significantly elevated compared to the controls hosts' cells, even on the second day of stimulation but not on the third. Regarding effects on cytokines, no significant changes were detected in the amount of Interferon-γ (IFNγ) and Interlukin-10 (IL-10) produced by lymphocytes obtained from the spleens of any of the shocked mice. These results could suggest that certain acute stressors might actually strengthen a host's immunological reactivity and, possibly, result in an enhanced capacity to resist pathogens that might infect the body.  相似文献   
19.
Watermelon mosaic virus (WMV) is one of the most important viruses that causes different symptoms in Cucurbitaceae. WMV is a potyvirus with a worldwide distribution, but occurs most commonly in temperate and Mediterranean regions. Cucurbit species grown in Yazd, Esfahan, West Azerbaijan, Hormozgan, and Kerman provinces were surveyed for the relative incidence of WMV in 2004–2005. A total of 757 symptomatic cucurbit and 31 weed species were collected and assayed for infection with WMV. Of 788 leaf samples from cucurbit and weed plants, 190 samples were positive by double antibody sandwich ELISA (DAS-ELISA) using specific polyclonal antibody. Among the weed species tested only colocynth (Citrullus colocynthis) was found to be infected with WMV. The coat protein (CP) gene from 18 representative isolates was PCR amplified, cloned, sequenced, and compared with the sequences available in GeneBank. Phylogenetic analysis using 778 nucleotide long sequences of the coat protein gene showed that these isolates fell into two; groups I and II. Only one isolates (KER.JI.1) was classified in the group II. This isolate had a wider host range and infected Nicotiana debneyii and Datura metel. None of the other 17 isolates could infect these two species. Members of group I were divided into three subgroups; A, B, and C. The subgroup IB appears to be a new subgroup comprising only of the Iranian isolates. Phylogenetic analysis based on 200 nucleotides coding for the N-terminal segment of the CP showed that all Iranian isolates except KER.JI.1 clustered with the previously reported WMV strains. All Iranian isolates had a DAG amino acid triplet which is involved in aphid transmissibility. This is the first report on sequence analysis of the nearly full-length CP cDNA clones of WMV isolates from Iran.  相似文献   
20.
OBJECTIVE: To present standardized percentile curves of body mass index (BMI) for Iranian children, and compare these to the US population reference. SUBJECTS: 1599 boys and 1702 girls aged 2-18 y living in urban Tehran as a part of a random cluster sample survey of 1 in 1000 families throughout Iran. MEASUREMENTS: Heights (cm) and weights (kg) were collected by trained health staff. RESULTS: Standardized BMI reference curves for Iranian boys and girls were constructed. The curves are shown to fit the data well. The development pattern of BMI for boys and girls are compared. CONCLUSIONS: The major differences observed between Iranian and the US BMI charts underline the need for population-specific reference data. For children over six years the 5th and 95th percentiles of our data may be used provisionally as cut-off points for defining thinness and obesity for Iranian children and adolescents.  相似文献   
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