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101.
SUMMARY This report of a paraplegic patient with a primary peritonitis illustrates the difficulty in diagnosis and management these patients pose.  相似文献   
102.
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   
103.
Since considerable first-pass effects of azosemide have been reported after oral administration of the drug to rats and man, first-pass effects of azosemide were evaluated after intravenous, intraportal and oral administration, and intraduodenal instillation of the drug, to rats. The total body clearances of azosemide after intravenous (5 mg kg?) and intraportal (5 and 10 mg kg?) administration of the drug to rats were considerably smaller than the cardiac output of rats suggesting that the lung or heart first-pass effect (or both) of azosemide after oral administration of the drug to rats was negligible. The total area under the plasma concentration-time curve from time zero to time infinity (AUC) after intraportal administration (5 mg kg?) of the drug was significantly lower than that after intravenous administration (5 mg kg?) of the drug (1000 vs 1270 μg min mL?) suggesting that the liver first-pass effect of azosemide was approximately 20% in rats. The AUC from time 0 to 8 h (AUC0–8 h) after oral administration (5 mg kg?) of the drug was considerably smaller than that after intraportal administration (5 mg kg?) of the drug (271 vs 1580 μg min mL?) suggesting that there are considerable gastrointestinal first-pass effects of azosemide after oral administration of azosemide to rats. Although the AUC0–8 h after oral administration (5 mg kg?) of azosemide was approximately 15% lower than that after intraduodenal instillation (5 mg kg?) of the drug (271 vs 320 μg min mL?), the difference was not significant, suggesting that the gastric first-pass effect of azosemide was not considerable in rats. Azosemide was stable in human gastric juices and pH solutions ranging from 2 to 13. Almost complete absorption of azosemide from whole gastrointestinal tract was observed after oral administration of the drug to rats. The above data indicated that most of the orally administered azosemide disappeared (mainly due to metabolism) following intestinal first-pass in rats.  相似文献   
104.
Outcome of tunneled hemodialysis catheters placed by radiologists   总被引:13,自引:1,他引:12  
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105.
Multivariate discriminant analysis was used to evaluate the usefulness of routine semen parameters and the hypo-osmotic swelling test (HOST) as predictors of the in-vitro fertilizing capacity of human sperm as assessed by the zona-free hamster egg penetration assay (HEPA). Eighty-eight semen samples from untreated patients attending an infertility clinic were analysed. Semen samples were classified into the following three groups before statistical analysis: group 1--positive sperm penetration (greater than or equal to 10%, n = 39); group 2--borderline penetration rates for HEPA (greater than 0% but less than 10%, n = 39) and group 3--negative sperm penetration (0%, n = 10). The percentage of sperm with normal morphology and sperm count were found to be significant in discriminating between semen samples exhibiting different in-vitro fertilizing capacity. These two discriminating variables in combination gave an overall correct classification rate of 45.5%. The multivariate discriminant analysis was also performed after excluding the data of group 2 semen samples (n = 39), which exhibited borderline sperm penetration rates. As a result, three discriminating variables including semen volume, sperm count and the percentage of sperm with normal morphology were selected. These three variables in combination could accurately predict whether a semen sample would exhibit positive sperm penetration (group 1) or negative sperm penetration (group 3) with an overall accuracy of 75.5%. The percentage of swollen sperm after hypo-osmotic treatment was not related to the HEPA result, as determined by linear correlation and multiple regression analyses, and did not give additional information about the in-vitro fertilizing capacity of sperm as evaluated by multivariate discriminant analysis.  相似文献   
106.
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   
107.
Sodium cromoglycate (SCG) powder often clumps in the presence of high humidity, making inhalation ineffective. A pressurized aerosol containing 1 mg SCG per actuation was made; and a double-blind cross-over trial in twenty-four young patients with perennial extrinsic asthma over 8 weeks showed that 2 mg of SCG aerosol was as effective as 20 mg of the powder, and almost all patients preferred using the aerosol.  相似文献   
108.
109.
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   
110.
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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