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To assist in the selection of a preferable vitamin A deficiency control policy, a model has been developed to organize information on program costs and program-related effects. The model was designed to compare three approaches: (1) diet modification; (2) fortification of processed foods; and (3) periodic large doses. Health effects projected are rates of specific eye pathologies associated with vitamin A deficiency (xerophthalmia), and mortalities within age cohorts. Effectiveness is calculated as a function of coverage, biological efficacy, and incidence of vitamin A deficiency. The model was applied to data from the Province of West Java in Indonesia. The results of this application suggest that funding level considerations are an important factor in selecting a preferred control strategy. In addition to determining the relative resource requirements of alternative interventions aimed at reducing the morbidity and mortality effects of vitamin A deficiencies, the model, using marginal cost and marginal effectiveness information, can serve as a guide to the most efficient allocation of resources for each type of intervention.  相似文献   
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In most individuals, natural killer (NK) activity is abolished after lymphocyte irradiation with 3,000 cGy, while lymphocytes from a minority of males retain 100% NK activity and lymphocytes from some females retain 50% NK activity after this dose. Radiation sensitivity of NK activity is controlled by X-linked codominant genes. The frequency of the allele that imparts resistance is 7%. We studied a unique family in which both parents have the resistant allele such that the father is completely resistant and the mother is partially resistant. The three offspring of this couple were one sensitive male, one partially resistant female, and one completely resistant female. The radiation sensitivity of nonspecific cytotoxic functions mediated by various types of effector cells from all five family members were evaluated in order to determine whether other cytotoxic functions were controlled by the same set of genes. The cytotoxic functions investigated were: NK and lymphokine-activated killing, anomalous killing and lectin-dependent cellular cytotoxicity, and antibody-dependent cell-mediated cytotoxicity. Our data indicate that the radiation sensitivity of all types of nonspecific cytotoxic cells is under the same genetic control.  相似文献   
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We evaluated the capacity of retinoids to potentiate proliferative responses of murine T-cells to recombinant human interleukin 2 (rIL-2). Concanavalin A (Con A) prestimulated spleen cells responded in a dose-dependent manner to added rIL-2. All-trans-retinoic acid (RA) at 10(-8) M potentiated the proliferative response by fivefold at saturating levels of IL-2. In similar experiments, two closely related retinamides, all-trans-(phenyl)retinamide (PR) and N-(4-hydroxyphenyl)retinamide (4-HPR), also potentiated murine splenocyte rIL-2 responses. Potentiation of IL-2-induced proliferation was dose-responsive to the concentration of added retinoid with peak potentiation occurring at 10(-10) - 10(-8) M in the presence of 10 U/ml rIL-2. Significant potentiation was observed at retinoid concentrations as low as 10(-14) M. Fluorescence flow cytometry of the responding cells revealed that among L3T4+, Lyt-2+ or total T-cells, at 72 h following Con A stimulation, essentially all of the cells expressed IL-2 receptors (IL-2R). This apparently represents near maximum IL-2R expression and treatment of the cells with retinoids did not increase IL-2R expression at that time point. The potentiation of IL-2 responses by retinoids was also observed with IL-2-dependent HT-2 cells, 98% of which were IL-2R positive. HT-2 proliferative responses to rIL-2 were potentiated as much as fourfold by 10(-10) M RA. HT-2 proliferative responses to rIL-2 were potentiated by all three retinoids dose dependently. Significant potentiation was observed with as little as 10(-14) M retinoid. Retinoids in the absence of IL-2 induced no proliferative responses. These data suggest that retinoids can augment the capacity of IL-2 to induce T-cell proliferation using Con A-activated murine splenic T-cell blasts and a long-term-cultured T-cell line.  相似文献   
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Objective: Bronchial thermoplasty (BT) as an add-on therapy for uncontrolled severe asthma is an alternative to biologic therapies like omalizumab (OM). We conducted an indirect treatment comparison (ITC) to appraise comparative effectiveness of BT and OM. Methods: A systematic literature review identified relevant randomized controlled trials. The ITC followed accepted methodology. Results: The ITC comprised a sham-controlled trial of BT (AIR2) and two placebo-controlled trials of OM (INNOVATE; EXTRA). Comparing the BT post-treatment period to ongoing treatment with OM, showed no significant differences in the rate ratios (RRs) for severe exacerbations (RR of BT versus OM = 0.91 [95% CI: 0.64, 1.30]; p = 0.62) or hospitalizations (RR = 0.57 [95% CI: 0.17, 1.86]; p = 0.53); emergency department visits were significantly reduced by 75% with BT (RR = 0.25 [95% CI: 0.07, 0.91]; p = 0.04); the proportions of patients with clinically meaningful response on the asthma quality-of-life questionnaire were comparable (RR = 1.06 [95% CI: 0.86, 1.34]; p = 0.59). The RR for exacerbations statistically favours OM over the total study period in AIR2 (RR = 1.50 [95% CI: 1.11, 2.02]; p = 0.009) likely reflecting a transient increase in events during the BT peri-treatment period. Conclusions: The ITC should be interpreted cautiously considering the differences between patient populations in the included trials. However, based on the analysis, BT compares well with a potentially more costly pharmacotherapy for asthma. Clinicians evaluating the relative merits of using these treatments should consider the totality of evidence and patient preferences to make an informed decision.  相似文献   
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BACKGROUND/OBJECTIVES

The relationship between food intake and nutritional status has been clearly established. Yet, there are only limited studies on food intake among family members and their nutritional status. The study examined the relationship between intra-household food distribution and coexistence of dual forms of malnutrition (DFM) in the same household.

SUBJECTS/METHODS

Households with a malnourished child and overweight mother were categorized as DFM. Intra-household food distribution among family members was reported using ratios, which are a measure of individual intakes as compared to all household member intakes adjusted to RDA.

RESULTS

A 1,899 families were included in the study. The prevalence of DFM was 29.8% (95%CI 26.5-31.2). Children consumed lower amounts of energy (OR 1.34; 95%CI 1.06-1.69, P = 0.011), carbohydrates (OR 1.2; 95%CI1.03-1.61, P = 0.022), protein (OR 1.3; 95%CI 1.03-1.64, P = 0.026), and fat (OR 1.3; 95%CI 1.05-1.66, P = 0.016) than their mothers and other family members. In contrast, mothers consumed more carbohydrates than children and other family members (OR1.24; 95%CI 1.02-1.51, P = 0.03).

CONCLUSIONS

This study is the first to report on the food distribution among family members and its relationship with occurrence of DFM in Indonesia. The results confirm the occurrence of an unequal food distribution between children and mothers, which increases risk of DFM in the household. The results also demonstrate that nutritional education at the household level is important to increase awareness of the impact of DFM.  相似文献   
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In the experiments here reported, definite verruga lesions, in which the presence of Bartonella bacilliformis was established by culture or by passage to rhesus monkeys, were produced in a dog and in a donkey by inoculation of cultures or monkey passage strains. The reaction induced in these animals was entirely local, however; blood cultures were sterile. Histologically, the lesions produced were similar to those obtained in monkeys by inoculation of Bartonella bacilliformis, except for the presence of a marked polynuclear leucocytic exudate. In another donkey a lesion histologically suggestive of verruga was produced, while in one donkey and a horse the results of inoculation were negative or indefinite. The intravenous injection of a filtrate or of heat-killed cultures of Bartonella bacilliformis into two donkeys was followed by the appearance of large, soft, subcutaneous swellings, on various parts of the body, not resembling in any way verruga lesions.  相似文献   
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