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71.
72.
The dual sugar test of intestinal permeability is a reliable non-invasive way of assessing the response of the small intestinal mucosa to nutritional rehabilitation. AIM: To compare a local mix of maize-soya-egg to the standard milk diet in the treatment of kwashiorkor. DESIGN: The diets were alternated three monthly in the sequence milk-maize-milk. There were a total of 533 kwashiorkor admissions of at least five days during the study who received either milk or maize. Intestinal permeability was assessed at weekly intervals by the lactulose-rhamnose test in 100 kwashiorkor cases, including 55 on milk and 45 on the maize diet. RESULTS: Permeability ratios (95% confidence interval) on the milk diet improved by a mean of 6.4 (1.7 to 11.1) compared with -6.8 (-16.8 to 5.0) in the maize group. The improved permeability on milk occurred despite more diarrhoea, which constituted 34.8% of hospital days (29.8 to 39.8) compared with 24.3% (17.8 to 30.8) in the maize group. Case fatality rates for all 533 kwashiorkor admissions were 13.6% v 20.9%, respectively, giving a relative risk of death in the maize group of 1.54 (1.04 to 2.28). The maize group also had more clinical sepsis (60% v 31%) and less weight gain (2.9 v 4.4 g/kg/day) than the milk group. IMPLICATIONS: Milk is superior to a local maize based diet in the treatment of kwashiorkor in terms of mortality, weight gain, clinical sepsis, and improvement in intestinal permeability.  相似文献   
73.
A new model to predict final height in constitutionally tall children   总被引:2,自引:0,他引:2  
In order to develop new height prediction models for children with constitutionally tall stature, 55 such boys and 88 girls were recalled for measurement of adult final height (FH). Data on height (H), age (CA), and target height (TH) were collected from the hospital charts and radiographs of the left hand and wrist were retrieved and used for bone age (BA) determination [BA according to the methods of Greulich and Pyle (BAGP) and Tanner and Whitehouse (BARUs)]- Standard multiple regression techniques were used to develop prediction equations for FH. In addition, to test the validity of the new equations, FH was measured in a second group of constitutionally tall children (n = 32) and compared with the predicted FH according to our models. In addition, a comparison was made with other prediction methods. Mean (SD) FH was 196.0 (4.9) cm in boys and 180.5 (3.8) cm in girls. The ultimate regression equation was FH (cm) = 216.07 + 0.75 × H + 0.25 × TH - 11.09 × CA - 14.02 × BAOP+ 0.74 × (CA × BAGP) for boys and FH = 161.42 + 0.73 × H + 0.15 × TH - 8.41 × CA - 8.83 × BARUS - 2.45 × M + 0.55 × (CA × BARUS) for girls. The models showed satisfying accuracy: the mean (SD) errors were −1.4 (3.2) cm for boys and −0.5 (3.1) cm for girls with corresponding mean (SD) absolute errors of 2.7 (2.2) cm and 2.0 (2.4) cm, respectively. Compared with the current prediction methods, the new models were quite promising. Their clinical validity has to be ascertained in larger groups of tall children.  相似文献   
74.
75.
We have analyzed the sequence of the beta globin gene of a chromosome that is linked to the occurrence of an inclusion body beta-thalassemia characterized in the heterozygote by moderate anemia, severe red cell abnormalities, splenomegaly, inclusion body formation, elevated Hb A2 levels, and an increased in vitro alpha/beta chain synthetic ratio. The data indicate a change in codon 114 from CTG (Leu) to -GG that resulted in a frameshift and the presumed synthesis of an abnormal beta chain that is 156 residues long with a completely different C-terminal amino acid sequence. The change in codon 114 gives a -GGGCCC- sequence that creates a new ApaI site; the resulting 2.6-kilobase fragment has been observed in all subjects with this thalassemia condition. Protein structural analyses failed to demonstrate any trace of the abnormal beta chain, even in reticulocytes and nucleated red cells that were isolated by density gradient centrifugation. The inclusion bodies appear to contain mainly normal alpha chains. It is assumed that the structure of the beta-Geneva chain prevents it from combining with normal alpha chains; this results in a rapid breakdown of the abnormal protein during the early stages of red cell maturation and an accumulation of free alpha chains.  相似文献   
76.
77.
Epidemiological studies have consistently shown associations between elevated concentrations of urban particulate matter (UPM) air pollution and exacerbations of asthma and chronic obstructive pulmonary disease, which are both associated with viral respiratory infections. The effects of UPM on dendritic cell (DC) ‐stimulated CD4 T lymphocytes have been investigated previously, but little work has focused on CD8 T‐lymphocyte responses despite their importance in anti‐viral immunity. To address this, we examined the effects of UPM on DC‐stimulated naive CD8 T‐cell responses. Expression of the maturation/activation markers CD83, CCR7, CD40 and MHC class I on human myeloid DCs (mDCs) was characterized by flow cytometry after stimulation with UPMin vitro in the presence/absence of granulocyte–macrophage colony‐stimulating factor (GM‐CSF). The capacity of these mDCs to stimulate naive CD8 T‐lymphocyte responses in allogeneic co‐culture was then assessed by measuring T‐cell cytokine secretion using cytometric bead array, and proliferation and frequency of interferon‐γ (IFN‐γ)‐producing T lymphocytes by flow cytometry. Treatment of mDCs with UPM increased expression of CD83 and CCR7, but not MHC class I. In allogeneic co‐cultures, UPM treatment of mDCs enhanced CD8 T‐cell proliferation and the frequency of IFN‐γ+ cells. The secretion of tumour necrosis factor‐α, interleukin‐13, Granzyme A and Granzyme B were also increased. GM‐CSF alone, and in concert with UPM, enhanced many of these T‐cell functions. The PM‐induced increase in Granzyme A was confirmed in a human experimental diesel exposure study. These data demonstrate that UPM treatment of mDCs enhances priming of naive CD8 T lymphocytes and increases production of pro‐inflammatory cytokines. Such UPM‐induced stimulation of CD8 cells may potentiate T‐lymphocyte cytotoxic responses upon concurrent airway infection, increasing bystander damage to the airways.  相似文献   
78.
SUMMARY Cefuroxime axetil 250 mg twice daily and amoxycillin 250 mg three times daily were compared in an investigator-blind, randomised, parallel group, multicentre study of acute or acute-on-chronic bronchitis. The two compounds had broadly similar efficacy. Analysis of patients on an intention-to-treat basis 24-72 hours after completion of the course of study medication showed that amoxycillin afforded clinical cure or improvement in 123/153 (80.4%) of patients and cefuroxime axetil in 109/143 (76.2%). This result was not significantly different, but the amoxycillin cure rate was not sustained and there were significantly more clinical relapses during the 4-week follow-up period following the end of treatment. Only 4/68 (5.9%) of patients receiving cefuroxime axetil relapsed and required further treatment, whereas 16/77 (20.8%) of those receiving amoxycillin needed further treatment (P=0.016). These were all patients who had initially responded to treatment and had been adjudged clinically cured or improved. The significant difference in relapse rates suggests that the apparent clinical success with amoxycillin was not sustained. There were no differences between the two treatments in the numbers of patients experiencing adverse events, which were generally mild and transient.  相似文献   
79.

Background and purpose:

Δ9-tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, accumulates in adipose tissue where it is stored for long periods of time. Here we investigated whether conditions that promote lipolysis can liberate THC from adipocytes to yield increased blood levels of THC.

Experimental approach:

In vitro studies involved freshly isolated rat adipocytes that were incubated with THC before exposure to the lipolytic agent adrenocorticotrophic hormone (ACTH). A complementary in vivo approach examined the effects of both food deprivation and ACTH on blood levels of THC in rats that had been repeatedly injected with THC (10 mg·kg−1) for 10 consecutive days. Lipolysis promoted by ACTH or food deprivation was indexed by measurement of glycerol levels.

Key results:

ACTH increased THC levels in the medium of THC-pretreated adipocytes in vitro. ACTH also enhanced THC release from adipocytes in vitro when taken from rats repeatedly pretreated with THC in vivo. Finally, in vivo ACTH exposure and 24 h food deprivation both enhanced the levels of THC and its metabolite, (-)-11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) in the blood of rats that had been pre-exposed to repeated THC injections.

Conclusions and implications:

The present study shows that lipolysis enhances the release of THC from fat stores back into blood. This suggests the likelihood of ‘reintoxication’ whereby food deprivation or stress may raise blood THC levels in animals chronically exposed to the drug. Further research will need to confirm whether this can lead to functional effects, such as impaired cognitive function or ‘flashbacks’.  相似文献   
80.

Background  

This study conducted in Northeastern Brazil, evaluated the prevalence of H. pylori infection and the presence of gastritis in HIV-infected patients.  相似文献   
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