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81.
Observation of a cohort of preschool children in Dhaka, Bangladesh, is beginning to reveal the contributions of environment, host, and parasite to amebiasis. Reviewed here are the associations and interactions of malnutrition, IgA and interferon-γ, human leukocyte antigen alleles, and parasite genotypes to the outcome of infection. Future efforts aimed at understanding the mechanisms of these effects are described.  相似文献   
82.
Bronchopulmonary dysplasia: radiographic appearance in middle childhood   总被引:1,自引:0,他引:1  
Chest radiographs were compared for three groups of children 8-9 years old: 23 survivors of bronchopulmonary dysplasia (BPD), 33 survivors of hyaline membrane disease without BPD, and 35 survivors of premature birth without neonatal respiratory problems. Only four children in the second group and three in the third had abnormal lungs. Linear shadows, apparently representing strands of fibrosis or deep pleural fissuring, were seen more frequently (15 of 23) in the BPD group than in the others (P less than .0001). Seventeen children in the BPD group had definite pulmonary abnormalities, none of them severe. The anteroposterior dimension of the chest in survivors of BPD tended to be decreased (P less than .001 vs that of reported control subjects).  相似文献   
83.
Twenty-five female patients of septicaemia aged 15-50 years comprised this study. Twenty-three patients (92%) were in the reproductive age group (15-35 years). Sixteen patients (64%) had some relation to parity, suggesting an increased risk of septicaemia in women with puerperal sepsis. The commonest primary source of infection was the female genital tract (48%). Gram-negative septicaemia was the commonest. The pleuropulmonary complications observed were pneumonia (10 cases), lung abscess (7 cases), empyema (3 cases), septic pulmonary embolisation (4 cases) and adult respiratory distress syndrome (4 cases). Seven cases of the total 25 died. Adult respiratory distress syndrome with septicaemia was the commonest cause of mortality in these patients.  相似文献   
84.
The effect of ouabain on the rabbit ear artery response to serotonin was assessed in isolated vascular rings mounted in tissue baths for the measurement of isometric contractions and denervated with 6-hydroxydopamine in vitro. Ouabain, 1 and 10 microM, caused 5- and 6-fold shifts to the left of the serotonin concentration-response curve (CRC). However, 10 microM ouabain caused only a 1.6-fold shift to the left of the norepinephrine CRC. In the absence of ouabain, 0.01 microM ketanserin had little effect, whereas 0.1 microM prazosin caused a marked shift to the right of the serotonin CRC. In the presence of ouabain, prazosin exhibited little or no antagonism below 3 microM serotonin. Antagonism by ketanserin was increased by 1 and 10 microM ouabain, yielding 6.5- and 10.5-fold shifts to the right of the serotonin CRC, respectively. Benextramine pretreatment to inactivate alpha adrenoceptors nearly abolished the rabbit ear artery response to serotonin. However, in the presence of 10 microM ouabain, there was a substantial recovery of the response to serotonin, and this response was antagonized by ketanserin. These results are consistent with our hypothesis that serotonergic receptors are present in the smooth muscle cell membranes of the rabbit ear artery but are either uncoupled to the contractile mechanism or in a low efficacy state. In the presence of ouabain, these receptors either become coupled or convert to a high efficacy state and thereby contribute to the serotonin-induced contraction. Because the serotonin CRC was shifted to the left in the presence of ouabain, it is likely that most of the CRC was below the threshold concentration at which serotonin activates alpha adrenoceptors. Thus antagonism by prazosin was lost.  相似文献   
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87.

Objective

High blood pressure is one of the most important risk factors, directly responsible for increasing the cardiovascular morbidity and mortality. The primary objective was to evaluate the efficacy of metoprolol XL/chlorthalidone against metoprolol XL/hydrochlorothiazide with respect to mean fall in systolic and diastolic blood pressure. The secondary objective was to compare the response rates and to evaluate the tolerability of study medications in patients with mild-tomoderate essential hypertension.

Methods

Total 130 eligible patients (65: metoprolol XL 25 mg/chlorthalidone 6.25 mg; 65: metoprolol XL 25 mg/HCTZ 12.5 mg) were enrolled in this randomized, comparative, multicentric, 12-weeks study. Sixty-two patients from each group completed the study. After 4-weeks of treatment, non-responders from chlorthalidone 6.25 mg combination group were shifted to metoprolol XL 50 mg/chlorthalidone 12.5 mg and non-responders from HCTZ 12.5 mg combination group were escalated to metoprolol XL 50 mg/HCTZ 12.5 mg.

Results

The study treatment groups were comparable with respect to demography and baseline disease characteristics. Both the starting therapies were comparable with respect to mean fall in SBP (p = 0.788) and DBP (p = 0.939), and response rates (p = 1.0) after 4-weeks of therapy. Also both the step-up therapies showed similar mean fall in SBP (p = 0.277) and DBP (p = 0.507) at the end of 12-weeks. However, significantly more number of patients from chlorthalidone 12.5 mg/metoprolol XL 50 mg group responded to therapy as compared to that from HCTZ 12.5 mg/metoprolol XL 50 mg group (p = 0.045). All the reported adverse events were of mild-to-moderate intensity. There were no clinically significant trends in electrolytes (Na+, K+, Cl-)and fasting blood sugar, evident across the treatment groups.

Conclusion

Chlorthalidone in combination with metoprolol XL is as effective and well tolerated as widely used combination of metoprolol XL/HCTZ, thus providing an alternative therapeutic option.  相似文献   
88.
In the search of developing herbal acaricides, eight medicinal plants were screened for their efficacy against Boophilus microplus, the widely distributed tick species in India. Of the seven extracts screened, the extracts prepared from the Annona squamosa seed showed very high level of efficacy (70.8%) after 24 h of treatment. The effect of treatment on oviposition of the survived ticks was also assessed, and a significant reduction (P < 0.05) in the reproductive index was noted in comparison to control. When efficacy of the in vitro optimized concentration of A. squamosa was compared with previously tested extract of Azadirachta indica in in vivo model, it was observed that the extracts prepared from A. indica is more efficacious than the extracts of A. squamosa. A comparable efficacy against B. microplus fed on animals treated with herbal extracts and commonly used synthetic acaricide was noted. The possibility of using the herbal extracts in IPM format for the management of ticks is discussed.  相似文献   
89.
Oral Diseases (2010) 16 , 136–145 Objective: The oral cavity forms an indispensable part of the human microbiome, for its unique and diverse microflora distributed within various niches. While majority of these organisms exhibit commensalism, shifts in bacterial community dynamics cause pathological changes within oral cavity and distant sites. The aim of this review was to appraise the current and emerging methods of detecting bacteria of the oral cavity paying particular attention to the cultivation independent methods. Design: Literature pertaining to cultivation based and cultivation independent methods of oral bacterial identification was reviewed. Methods: The specific advantages and disadvantages of cultivation based, microscopic, immunological and metagenomic identification methods were appraised. Results: Because of their fastidious and exacting growth requirements, cultivation based studies grossly underestimate the extent of bacterial diversity in these polymicrobial infections. Culture independent methods deemed more sensitive in identifying difficult to culture and novel bacterial species. Conclusion: Apart from characterizing potentially novel bacterial species, the nucleic acid sequence data analyzed using various bioinformatics protocols have revealed that there are in excess of 700 bacterial species inhabiting the mouth. Moreover, the latest pyrosequencing based methods have further broadened the extent of bacterial diversity in oral niches.  相似文献   
90.
An association between tumor necrosis factor α (TNF-α) and Entamoeba histolytica diarrhea was assessed in a cohort of 138 non-related Bangladeshi children who have been prospectively followed since 2001. Peripheral blood mononuclear cells (PBMCs) obtained at study entry were purified, cultured, and stimulated with soluble amebic antigen before cytokine measurement from supernatant. Higher levels of TNF-α were associated with increased risk of first (P = 0.01) and recurrent E. histolytica-related diarrheal episodes (P = 0.005). Children who developed E. histolytica diarrhea had significantly higher TNF-α protein levels than those who experienced asymptomatic E. histolytica infection (P value = 0.027) or no infection (P value = 0.017). Microarray studies performed using RNA isolated from acute and convalescent whole blood and colon biopsy samples revealed higher but non-significant TNF-α messenger RNA (mRNA) levels in subjects with acute E. histolytica diarrhea compared with convalescence. We conclude that there is an association between higher TNF-α production and E. histolytica diarrhea.  相似文献   
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