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41.
We have previously shown that a pneumococcal surface protein A (PspA)-based vaccine containing DNA plasmid encoding the Flt3 ligand (FL) gene (pFL) as a nasal adjuvant prevented nasal carriage of Streptococcus pneumoniae. In this study, we further investigated the safety and efficacy of this nasal vaccine for the induction of PspA-specific antibody (Ab) responses against lung infection with S. pneumoniae. C57BL/6 mice were nasally immunized with recombinant PspA/Rx1 (rPspA) plus pFL three times at weekly intervals. When dynamic translocation of pFL was initially examined, nasal pFL was taken up by nasal dendritic cells (DCs) and epithelial cells (nECs) but not in the central nervous systems, including olfactory nerve and epithelium. Of importance, nasal pFL induced FL protein synthesis with minimum levels of inflammatory cytokines in the nasal washes (NWs) and bronchoalveolar lavage fluid (BALF). NWs and BALF as well as plasma of mice given nasal rPspA plus pFL contained increased levels of rPspA-specific secretory IgA and IgG Ab responses that were correlated with elevated numbers of CD8(+) and CD11b(+) DCs and interleukin 2 (IL-2)- and IL-4-producing CD4(+) T cells in the nasal mucosa-associated lymphoid tissues (NALT) and cervical lymph nodes (CLNs). The in vivo protection by rPspA-specific Abs was evident in markedly reduced numbers of CFU in the lungs, airway secretions, and blood when mice were nasally challenged with Streptococcus pneumoniae WU2. Our findings show that nasal pFL is a safe and effective mucosal adjuvant for the enhancement of bacterial antigen (Ag) (rPspA)-specific protective immunity through DC-induced Th2-type and IL-2 cytokine responses.  相似文献   
42.
BackgroundSleep-disordered breathing (SDB) is common in patients with heart failure and carries an independent risk for poor long-term prognosis. We aimed to study the effects of supervised, aerobic exercise training for 6 months on SDB in patients with chronic heart failure.Methods and ResultsWe enrolled 18 patients having both systolic dysfunction (left ventricular ejection fraction <45%) and SDB (apnea-hypopnea index [AHI] >10). The exercise group comprised 10 patients who participated in our cardiac rehabilitation program for 6 months, and the remaining 8 patients served as control. AHI (median [interquartile range]) was unchanged in the control group patients at 6-month intervals (30.4 [19.9–36.3] versus 36.6 [8.6–39.4], NS). In contrast, AHI was significantly decreased in the exercise group from 24.9 [19.2–37.1] to 8.8 [5.3–10.1] (P < .01). In the exercise group, the numbers of central sleep apnea per night was significantly decreased (152 [124–244] versus 50 [24–67], P < .01) after exercise training, but those of obstructive apnea/hypopnea were unchanged (42 [7–94] versus 18 [7–54], NS). In addition, exercise training significantly increased peak oxygen consumption and decreased minute ventilation to carbon dioxide production slope (both P < .01).ConclusionsSix-month, aerobic exercise training increased exercise capacity and improved central sleep apnea in patients with chronic heart failure from systolic dysfunction.  相似文献   
43.
The aim of this study was to evaluate the efficacy of an oral vaccine containing the 40‐kDa outer membrane protein of Porphyromonas gingivalis (40K‐OMP) and synthetic oligodeoxynucleotides containing unmethylated CpG dinucleotides (CpG ODN) to control oral infection by P. gingivalis. Oral immunization with 40K‐OMP plus CpG ODN induced significant 40K‐OMP‐specific serum immunoglobulin G (IgG), IgA, and saliva IgA antibody responses. The 40K‐OMP‐specific CD4+ T cells induced by oral 40K‐OMP plus CpG ODN produced both T helper type 1 (Th1; interferon‐γ) and Th2 (interleukin‐4) cytokines. Furthermore, increased frequencies of CD11c+ B220+ dendritic cells (DCs) and CD11c+ CD11b+ DCs with upregulated expression of CD80, CD86, CD40, and major histocompatibility complex class II molecules were noted in spleen, Peyer’s patches, and cervical lymph nodes. Immunized mice were then infected orally with P. gingivalis to determine whether the immune responses induced by oral 40K‐OMP plus CpG ODN were capable of suppressing the bone resorption caused by P. gingivalis infection. Mice given 40K‐OMP plus CpG ODN showed significantly reduced bone loss associated with oral infection by P. gingivalis. Oral administration of 40K‐OMP together with CpG ODN induces Th1‐type and Th2‐type cells, which provide help for protective immunity against P. gingivalis infection. This may be an important tool for the prevention of chronic periodontitis.  相似文献   
44.
Pancreatic beta-cells possess a well-regulated insulin secretory property that maintains systemic glucose homeostasis. Although it has long been thought that differentiated beta-cells are nearly static, recent studies have shown that beta-cell mass dynamically changes throughout the lifetime. The beta-cell mass could be maintained by several mechanisms, including self-replication of pre-existing beta-cells, neogenesis from unidentified stem/progenitor cells, and transdifferentiation from differentiated duct or acinar cells. Recent studies have suggested that self-replication of pre-existing beta-cells is a major source for maintenance of beta-cell mass in adult pancreas. However, regeneration of beta-cells from non-beta-cells does occur under certain conditions, especially in vitro culture systems. In this article, recent progress of regenerative medicine of the pancreas is reviewed.  相似文献   
45.
There have been conflicting reports over the JAK2-V617F mutation status of platelets in chronic myeloproliferative diseases (CMPDs). The aim of this study was to analyse JAK2-V617F status, not only in granulocytes but also in platelets. The JAK2-V617F mutation was analysed in both granulocytes and platelets in 115 patients with CMPDs using direct sequencing. JAK2-V617F was detected in granulocytes from 71 of those patients, all 71 of whom also had platelet JAK2-V617F expression. The remaining 44 patients showed negative JAK2-V617F expression on granulocytes, but positive JAK2-V617F expression was detected on the platelets from nine of the 33 essential thrombocythaemia (ET) patients, one of the eight polycythaemia vera patients, and two of the three primary myelofibrosis patients. When ET patients were divided into three groups according to granulocyte and platelet JAK2-V617F status (both-positive, platelets-only positive and both-negative), the both-positive and platelets-only positive groups shared the clinical features of higher white blood cell count and frequent thrombosis. These results suggest that analysis of platelets is a more sensitive approach for detecting JAK2-V617F in CMPD patients than analysis of granulocytes. They also suggest that previous reports of the incidence of JAK2-V617F in CMPD patients, obtained using only analysis of granulocytes, could be underestimations.  相似文献   
46.
Pulmonary arterial hypertension is a progressive and fatal disease for which Rho-kinase may be substantially involved. In this study, we examined the acute vasodilator effects of fasudil, a Rho-kinase inhibitor, in monocrotaline (MCT)-induced pulmonary hypertension (PH) in rats. Three weeks after a single subcutaneous injection of MCT (60 mg/kg), hemodynamic variables were measured under conscious and free-moving conditions before and after oral administration of fasudil. MCT caused a significant elevation of mean pulmonary arterial pressure (mPAP). Although a low dose of fasudil (3 mg/kg) had no effect on mPAP, a middle dose (10 mg/kg) caused a significant reduction in mPAP without change in mean systemic arterial pressure (mSAP), and a high dose (30 mg/kg) significantly reduced both mPAP and mSAP. Rho-kinase activity was significantly increased by MCT injection in pulmonary arteries but not in the aorta. Fasudil (10 mg/kg) inhibited only the Rho-kinase activity in pulmonary arteries without any effect in the aorta. Plasma concentration of hydroxyfasudil, a metabolite of fasudil, was within its clinical range in humans. These results demonstrate that fasudil exerts effective and selective vasodilatation of pulmonary arteries in rats with MCT-induced PH at a given dose, suggesting its usefulness for the treatment of the fatal disorder.  相似文献   
47.
Orotidine 5'-monophosphate decarboxylase (ODCase) has evolved to catalyze the decarboxylation of orotidine 5'-monophosphate without any covalent intermediates. Active site residues in ODCase are involved in an extensive hydrogen-bonding network. We discovered that 6-iodouridine 5'-monophosphate (6-iodo-UMP) irreversibly inhibits the catalytic activities of ODCases from Methanobacterium thermoautotrophicum and Plasmodium falciparum. Mass spectral analysis of the enzyme-inhibitor complex confirms covalent attachment of the inhibitor to ODCase accompanied by the loss of two protons and the iodo moiety. The X-ray crystal structure (1.6 A resolution) of the complex of the inhibitor and ODCase clearly shows the covalent bond formation with the active site Lys-72 [corrected] residue. 6-Iodo-UMP inhibits ODCase in a time- and concentration-dependent fashion. 6-Iodouridine, the nucleoside form of 6-iodo-UMP, exhibited potent antiplasmodial activity, with IC50s of 4.4 +/- 1.3 microM and 6.2 +/- 0.7 microM against P. falciparum ItG and 3D7 isolates, respectively. 6-Iodouridine 5'-monophosphate is a novel covalent inhibitor of ODCase, and its nucleoside analogue paves the way to a new class of inhibitors against malaria.  相似文献   
48.
This comparative immunohistochemical study deals with the expression of the cytosolic Cu/Zn-binding and mitochondrial Mn-dependent superoxide dismutases (SODs) in the cerebella of five patients with Menkes' kinky hair disease (MKHD) and five age-matched controls. Several cell types, including Purkinje cells and reactive astrocytes, of all MKHD patients examined were intensely stained by an antibody to Mn SOD, but not by an anti-Cu/Zn SOD antibody. By contrast, the cells of the five controls reacted very weakly or not at all with the anti-Mn SOD antibody, but were strongly reactive with the antibody to Cu/Zn SOD. These results suggest that the increased Mn SOD immunoreactivity in MKHD reflects enzyme induction as a protective mechanism against the highly toxic superoxide anion generated under the disease conditions.  相似文献   
49.
In July 2001, psychiatric wards for acute treatments (PWAT) were investigated in Japan using a questionnaire to clarify current and recent problems in 79 PWAT. The questionnaires were sent to wards, patients and psychiatrists and were returned by 72.2% overall. The number of admissions per ward was calculated as 21 patients per one month, and comprised half of all admissions to the hospital. 50% were schizophrenia, 17% were affective disordes and 16% involved drug abuse. Seventeen patients were discharged from PWAT per one month, and comprised 43% of all patients discharged from the hospital. These results indicate that both 21 patients admitted and 17 patients discharged per month and needs to maintain the essential standard for PWAT and the standard should be come more flexible as admission from the other unit of ward than PWAT. As rate of re-admission within 3 months after discharge was around 10% of the total number of patients in the ward, 3 months was considered suitable length of acute treatment in the field of psychiatry in Japan. There was one psychiatrist working in PWAT, and specialized psychiatrists had 17.4 patients, the most number of patients among types of psychiatrist. Simulations of one psychiatrist to 16 and to 32 patients in PWAT were performed to determine how many psychiatrists were needed for a ward. When the ratio was 32 patients to 1 psychiatrist, it was necessary to increase the number of psychiatrists to a ward by 1, and in the case of 16 patients, 1-3 psychiatrists were needed. These indicate the standard number of psychiatrists for PWAT should be at most one psychiatrist for the ward or all of the psychiatrists working in PWAT should be allowed to work simultaneously in other wards. Preparing wards to treat acute phase psychiatric patients is a very important role of each psychiatric hospital, the standard for PWAT should include not only a high level of medical staff, but also preparing easy criteria for each hospital.  相似文献   
50.
Botulism has classically been considered to be a food- and water-borne disease. However, it was recently classified by the US National Institute of Allergy and Infectious Diseases (National Institute of Health) and the US Centers for Disease Control and Prevention as a Category A agent. Thus, the botulinum exotoxin, a neurotoxin, could be easily disseminated by bioterrorists through the air-borne route with a high morbidity and mortality rate. In this regard, a high priority should be given to the development of a safe and effective mucosal vaccine to protect against botulinum neurotoxins (BoNTs) since it is well known that the mucosal immune system is the first line of defense against major pathogens. Further, mucosal immunization has been shown to induce both mucosal and systemic immunity to pathogens. By contrast, the current injection-type vaccine only provides protective immunity in the systemic compartment. Clearly, the development of a safe and effective mucosal vaccine against this toxin should be a high priority. In this regard, it has been shown that both nasal and oral immunization approaches have been taken in order to protect from BoNT intoxication. In this article, we will discuss the importance of the development of a mucosal vaccine against botulinum and introduce current aspects of BoNT mucosal vaccines, which show that they effectively prevent mucosal BoNT intoxication.  相似文献   
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