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43.

Objective

Hyoscine butyl bromide (HBB) is known for its antispasmodic action and has been in use for over five decades, there is however no consensus on its effectiveness in the labor process. The aim of this study was to determine the effect of HBB on the duration of the active phase of labor.

Materials and methods

A randomized double-blind placebo-controlled clinical trial involving 160 parturient who received either intravenous Hyoscine butyl-bromide (20 mg in 1 ml; n = 80) or intravenous normal saline (1 ml, n = 80). The mean duration of active phase of labor was compared between the two groups.

Results

The observed mean duration of the active phase of labor was significantly shorter (P = 0.001) in the Hyoscine butyl-bromide group (365.11 ± 37.32 min, range = 280–490) than in the Placebo group (388.46 ± 51.65 min, range = 280–525). There was no significant difference between the two groups in the mean duration of the second and third stages of labor (20.46 ± 10.46 vs. 23.38 ± 18.95 min, P = 0.43 and 8.96 ± 4.34 vs. 9.23 ± 5.92 min, P = 0.75, respectively). The mean 1-min APGAR scores were also comparable (8.08 ± 1.54 vs. 7.64 ± 1.60, P = 0.08). The mean postpartum blood loss was significantly less in the Hyoscine butyl-bromide group (303 ± 96.52 vs. 368 ± 264.19 ml, P = 0.04).

Conclusion

Hyoscine butyl-bromide was effective in shortening the duration of the active phase of labor. It was also associated with significantly less postpartum blood loss.  相似文献   
44.
A community-based survey to determine the prevalence of human T-cell lymphotropic type I (HTLV-I) and type II (HTLV-II) virus infections in mothers and children in south-western Nigeria was carried out using blood samples collected in 1993. A multistage cluster, random sampling procedure was used to select 460 mother-child pairs (476 children because there were 16 sets of twins) from 14 enumeration areas. A commercially available, whole HTLV-I lysate antigen-based ELISA method was used to screen for HTLV-I and HTLV-II antibodies in the samples. A synthetic peptide antigen-based ELISA was then used to differentiate between antibody reactivity to either HTLV-I or HTLV-II. Reactivity to HTLV-I or HTLV-II antibodies was found in 4.3 per cent (20/460) of mothers and in 1.1 per cent (5/476) of children in both rural and urban communities and all the positive children were males. None of the 16 sets of twins in this study was positive for either HTLV-I or HTLV-II. Also none of the mother-child paired sera tested showed concordance for either HTLV-I or HTLV-II antibody positivity. The lack of concordance between mother and child sera suggests that vertical transmission may not be the major route of transmission of HTLV infection to children in south-western Nigeria. Other modes of transmission, such as the re-use of unsterilized needles for injections and surgical knives in local scarification, which are common practices in the region, need to be investigated as they may prove to be more important than vertical transmission. These findings have important implications for any control programme for diseases that can be spread by the same routes as HTLV infection (the human immunodeficiency viruses, hepatitis B, and hepatitis C infections).  相似文献   
45.
The paper is devoted to studying the chemical elements distribution in the material’s structure depending on the manufacturing technological parameters and their effect on properties of a new self-lubricating antifriction composite based on powder nickel alloy EP975 with CaF2 solid lubricant for operation at temperature 800 °C and loads up to 5.0 MPa, in air. The study is focused on the features of alloying elements distribution in the composite matrix, which depends on the manufacturing technology. A uniform distribution of all alloying elements in the studied composite was shown. The chemical elements’ uniform distribution in the material is associated with one of the most important preparatory technological operations in the general manufacturing technology used. This is a technological operation of mixing powders with subsequent analysis of the finished mixture. The uniform distribution of chemical elements determines the uniform arrangement of carbides and intermetallics in the composite. General manufacturing technology, which includes the main operations, such as hot isostatic pressing technology and hardening heat treatment, contributed to the obtainment of a practically isotropic composite with almost the same properties in the longitudinal and transverse directions. Because of the composite’s structural homogeneity, without texturing, characteristics are isotropic. Improving the material’s structural homogeneity helps to keep its mechanical and anti-friction qualities stable at high temperatures and stresses in the air. The performed studies demonstrated the correctness of the developed manufacturing technology that was confirmed by the electron microscopy method, micro-X-ray spectral analysis, mechanical and tribological tests. The developed high-temperature antifriction composite can be recommended for severe operating conditions, such as friction units of turbines, gas pumping stations, and high-temperature units of foundry metallurgical equipment.  相似文献   
46.
This study aims to determine the prevalence of methotrexate-induced nausea and vomiting in both adolescent and adult patients with inflammatory arthritis. A survey of methotrexate side effects was conducted on patients with inflammatory arthritis. We provided a brief questionnaire to unselected patients with inflammatory arthritis being treated with methotrexate attending adolescent and adult rheumatology clinics. The questions related to the presence, absence, and severity of nausea and vomiting, the temporal relationship with methotrexate and whether anti-emetics had been prescribed. A total of 106 patients from the age of 13 years and above—57 adults (over 20 years) and 49 adolescents (13–19 years) were included in this study. The median age for those experiencing nausea was 19 years (interquartile range (IQR) 7) and for those with no nausea 55 years (IQR 46) (p?<?0.001). Thirty-six out of 49 adolescent patients reported nausea (73 %) compared to only 20/57 adults (35 %) (p?<?0.001). Multiple logistic regression analysis showed that the nausea group had a significantly higher proportion of adolescents (p?=?0.0002), patients taking subcutaneous (SC) methotrexate MTX (p?=?0.002), and patients with duration of MTX of more than 1 year (p?=?0.049). Adolescents were estimated to have over 6 times higher odds of nausea compared to adults (OR 6.31, 95 % CI 2.38 to 16.75, p?=?0.0002) after adjusting for SC MTX and duration of MTX. Only 22 % of adolescents and 10 % of adults were prescribed anti-emetics. There is a higher prevalence of MTX-induced nausea and vomiting in adolescents and younger adult patients with inflammatory arthritis compared to older adults. The role of anti-emetics in the treatment of these symptoms is unclear.  相似文献   
47.
BACKGROUND--In tropical Africa the role of microbial agents of acute respiratory infections in acute exacerbations of bronchial asthma remains largely unexplored. However, empirical antibacterial therapy is frequently initiated in moderate to severe cases of acute asthma with symptoms of acute respiratory infection. A study was set up to determine how often acute respiratory infection is associated with acute asthma, to identify the associated pathogens, and to proffer appropriate therapeutic suggestions. METHODS--Over a 16 month period, 86 episodes of acute asthma were studied for clinical and laboratory features of acute respiratory infection at the University College Hospital (UCH), Ibadan. Virological diagnosis was based on immunofluorescence studies of nasopharyngeal aspirates and/or serological tests using the microtitre complement fixation technique. Throat swabs and blood were cultured for bacterial agents. RESULTS--Of the 64 cases who presented with rhinorrhoea, 51 (79.7%) were pyrexial (T > or = 37.6 degrees C). Inflammatory changes (frequently interstitial streakiness) were identified in 10 (19.6%) of the 51 chest radiographs; only two of these had lobar shadowing. Significant bacterial isolates were made in only three (3.5%) of the throat swabs and two (2.4%) of the blood cultures from the 86 cases; none had clinical septicaemia. On the other hand, 55 viral agents were identified from 39 (53%) of the 74 subjects studied; 16 (41.0%) had dual viral identifications. Respiratory syncytial virus (RSV) accounted for 20 (36.4%) identifications, parainfluenza virus (PIV) type 3 for 15 (27.3%), and influenza type A (Flu A) for 12 (21.8%). Viral identifications were significantly higher in infants and preschool subjects (< 5 years) and in those presenting with either rhinorrhoea or pyrexia. CONCLUSIONS--The results of this study underscore the importance of viral upper respiratory infections in asthma exacerbations in a tropical setting. The paucity of clinical and investigative features of bacterial acute respiratory infection suggests that there is little rationale for routine antibiotic cover in children with acute exacerbations of asthma in the tropics.  相似文献   
48.
Healthy Gambian children, children with clinical Plasmodium falciparum malaria, and children with asymptomatic P. falciparum infections were studied to investigate whether antitoxic activities may contribute to protection against malarial symptoms. Markers of inflammatory reactions, soluble tumor necrosis factor receptor I, and C-reactive protein were found in high concentrations in children with symptomatic P. falciparum malaria compared with levels in children with asymptomatic P. falciparum infections or in healthy children, indicating that inflammatory reactions are induced only in children with clinical symptoms. Concentrations of soluble tumor necrosis factor receptor I and C-reactive protein were associated with levels of parasitemia. We detected antitoxic activities in sera as measured by their capacity to block toxin-induced Limulus amoebocyte lysate (LAL) activation. Symptomatic children had decreased capacity to block induction of LAL activation by P. falciparum exoantigen. The decreased blocking activity was restored in the following dry season, when the children had no clinical malaria. Symptomatic children also had the highest immunoglobulin G (IgG) reactivities to conserved P. falciparum erythrocyte membrane protein 1 and “Pfalhesin” (band #3) peptides, indicating that such IgG antibodies are stimulated by acute disease but are lost rapidly after the disease episode. Half of the children with symptomatic infections had low levels of haptoglobin, suggesting that these children had chronic P. falciparum infections which may have caused symptoms previously. Only a few of the children with asymptomatic P. falciparum infections had high parasite counts, and antitoxic immunity in the absence of antiparasite immunity appears to be rare among children in this community.  相似文献   
49.
It is not known whether the small 11-kDa Z protein of Lassa virus is immunogenic during human Lassa virus infection. To obtain evidence for the existence of an antibody response and to test the suitability of these antibodies for serosurveys, sera from Lassa fever endemic regions (Guinea and Nigeria, n = 75) were tested for co-reactivity to Z protein and nucleoprotein (NP). Sera from a non-endemic region (Uganda, n = 50) served as a specificity control. Z protein and NP were expressed in Escherichia coli, affinity-purified, and used as antigen in Western blot. Indirect immunofluorescence (IIF) with Lassa virus-infected cells was performed for comparison. Due to high unspecific reactivity of the African sera, Western blot testing was performed with a 1:1,000 serum dilution. Under these conditions, none of the control sera but 12% of the sera from endemic regions co-reacted with both Z protein and NP. Reactivity to Z protein was significantly associated with NP reactivity (P < 10(-6)). NP and Z protein-specific antibodies were co-detected in 33% of the IIF-positive sera and in 5% of the IIF-negative sera (P = 0.001). These data provide evidence for appearance of antibodies to Z protein and NP following Lassa virus infection. A recombinant blot for detection of both antibody specificities seems to be specific but less sensitive than IIF.  相似文献   
50.
1,4-Dinitrobenzene (1,4-DNB) is a synthetic compound used in explosives, dyes, organic chemicals and the plastic industry. Oral and dermal exposure is a likely route for industrial workers and people living near ammunition plants. This study investigated the effect of 1,4-DNB on testicular and spermatozoan antioxidant systems as well as sperm characteristics of Wistar rats. Oral exposure of male Wistar rats to 50 or 75 mg/kg, or dermal exposure to 1000 or 2000 mg/kg, of 1,4-DNB for 14 days increased spermic and testicular hydrogen peroxide and lipid peroxidation levels accompanied by decreased activities of enzymic antioxidants. Exposure to 1,4-DNB also resulted in decrease in body weight gain, reduced testicular and epididymal weights, epididymal degeneration, decrease in sperm quantity and quality, and mild congestion of interstitial vessels and edema in the testes. These results reveal that individuals unduly exposed to 1,4-DNB risk induction of oxidative stress in the epididymis and testis, and associated reproductive deficits.  相似文献   
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