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1.
Four cases of testicular feminization syndrome in Ethiopian patients are described. All four patients had normal female breasts, scanty pubic and axillary hair and absent internal genital organs. Three had bilateral inguinal or labial masses. The main features of their clinical presentation and histological studies are briefly discussed with a review of the literature.  相似文献   
2.
Helicobacter pylori is a common and persistent human pathogen of the gastric mucosa. Surfactant protein D (SP-D), a component of innate immunity, is expressed in the human gastric mucosa and is capable of aggregating H. pylori. Wide variation in the SP-D binding affinity to H. pylori has been observed in clinical isolates and laboratory-adapted strains. The aim of this study was to reveal potential mechanisms responsible for evading SP-D binding and establishing persistent infection. An escape variant, J178V, was generated in vitro, and the lipopolysaccharide (LPS) structure of the variant was compared to that of the parental strain, J178. The genetic basis for structural variation was explored by sequencing LPS biosynthesis genes. SP-D binding to clinical isolates was demonstrated by fluorescence-activated cell sorter analyses. Here, we show that H. pylori evades SP-D binding through phase variation in lipopolysaccharide. This phenomenon is linked to changes in the fucosylation of the O chain, which was concomitant with slipped-strand mispairing in a poly(C) tract of the fucosyltransferase A (fucT1) gene. SP-D binding organisms are predominant in mucus in vivo (P = 0.02), suggesting that SP-D facilitates physical elimination. Phase variation to evade SP-D contributes to the persistence of this common gastric pathogen.  相似文献   
3.
The aim of this study was to describe the distributions of superficial malignant neoplasms diagnosed by fine-needle aspiration cytology (FNAC). A prospective cross-sectional study was conducted within the Jimma Teaching Hospital, Pathology Department, Jimma University during the years between September 1998 and August 2002. Cases fulfilling cytopathological evidences of superficial malignancies were included whereas deep-seated malignancies were excluded from the study. An air-dried smear stained with the Wright staining procedure was utilized for the FNAC diagnostic technique. A total of 3,200 cases were investigated during the study period where 267 (8.3%) cases were of primary superficial malignant neoplasms, with 98 cases in the peak age group of 40-59 yr (36.7%) and a median age of 38.0 yr (range, 0.2-88 yr). The most frequent superficial cytodiagnosis was breast carcinoma, 79 (29.6%) cases; followed by non-Hodgkin's lymphomas, 37 (13.9%) cases; and soft tissue sarcomas, 26 (9.7%) cases. The overall male-to-female ratio showed preponderance to female patients (1:1.3). Carcinomas were identified more frequently in those >40 yr of age whereas sarcomas were identified in those <40 yr of age (P > 0.05). The most common malignant neoplasm in women was breast carcinomas found in 74 (27.7%) cases, whereas in men non-Hodgkin's lymphomas were found in 29 (10.9%) cases. Large proportions of carcinomas (88 cases, 33.0%), lymphomas (33 cases, 12.4%), and sarcomas (20 cases, 7.5%) were detected on the trunk, head, and neck, as well as on the lower limb regions, respectively. This study uncovered different types of superficial malignant neoplasms that are prevalent in the southwestern part of Ethiopia. The most common types of cytodiagnoses such as breast carcinomas, etc. may suggest that attention be given to future high-caliber prospective studies in trying to identify some of the associated strong risk factors for the disease under study. This study may be helpful to local health planners in prioritizing some of the commonest malignancies. Some of the diagnostic challenges of lymphomas and thyroid follicular lesions were shown also. This investigation is the first in Ethiopia and therefore may act as baseline data for similar studies in the future.  相似文献   
4.
The relationship between depression and vitamin D deficiency is complex, with evidence mostly from studies affected by confounding and reverse causality. We examined the causality and direction of the relationship between 25-hydroxyvitamin D (25(OH)D) and depression in bi-directional Mendelian randomization (MR) analyses using information from up to 307,618 white British participants from the UK Biobank and summary results from the SUNLIGHT (n = 79,366) and Psychiatric Genomics consortia (PGC 113,154 cases and 218,523 controls). In observational analysis, the odds of depression decreased with higher 25(OH)D concentrations (adjusted odds ratio (OR) per 50% increase 0.95, 95%CI 0.94–0.96). In MR inverse variance weighted (IVW) using the UK Biobank, there was no association between genetically determined serum 25(OH)D and depression (OR per 50% higher 0.97, 95%CI 0.90–1.05) with consistent null association across all MR approaches and in data from PGC consortium. In contrast, genetic liability to depression was associated with lower 25(OH)D concentrations (MR IVW −3.26%, −4.94%–−1.55%), with the estimates remaining generally consistent after meta-analysing with the consortia. In conclusion, we found genetic evidence for a causal effect of depression on lower 25(OH)D concentrations, however we could not confirm a beneficial effect of nutritional vitamin D status on depression risk.  相似文献   
5.
phenylanthraquinone knipholone (1) and three of its natural derivatives as well as seven structurally related but simplified compounds have been examined for their antiplasmodial activity against asexual erythrocytic stages of two strains of Plasmodium falciparum in vitro (K1/chloroquine-resistant and NF 54/chloroquine-sensitive). All the phenylanthraquinones showed considerable activity with only little cytotoxicity, while their anthraquinone and phenyl moieties were completely inactive. Knipholone (1) and its natural derivatives can therefore be considered as a new group of potential antimalarials  相似文献   
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The eight member states (Djibouti, Eritrea, Ethiopia, Kenya, Somalia, South Sudan, Sudan and Uganda) of the Intergovernmental Authority for Development (IGAD) have the largest proportions of cross-border mobile pastoralists and refugees in Africa. Although all IGAD countries have had national HIV/AIDS prevention, care and treatment programmes since the late 1980s, the IGAD Regional HIV & AIDS Partnership Program was (IRAPP) established in 2007 to mitigate the challenges of HIV among neglected pastoral and refugee communities. This article assesses vulnerability of pastoralists and refugee communities to HIV and interventions targeting these groups in the IGAD countries. Outcomes from this study may serve as a baseline for further research and to improve interventions. Published articles were accessed through web searches using PubMed and Google Scholar engines and unpublished documents were collected manually. The search terms were HIV risk behaviour, vulnerability, HIV prevalence and interventions, under the headings pastoralists, refugees, IGAD and north-east Africa for the period 2001–2014. Of the 214 documents reviewed, 78 met the inclusion criteria and were included. Most HIV/AIDS related studies focusing of pastoral communities in IGAD countries were found to be limited in scope and coverage but reveal precarious situations. Sero-prevalence among various pastoral populations ranged from 1% to 21% in Ethiopia, Kenya, Somalia and Uganda and from 1% to 5% among refugees in Sudan, Kenya and Uganda. Socioeconomic, cultural, logistic, infrastructure and programmatic factors were found to contribute to continuing vulnerability to HIV. Interventions need to be further contextualised to the needs of those impoverished populations and integrated into national HIV/AIDS programmes. HIV/AIDS remains a major public health concern among the pastoral and refugee communities of IGAD countries. This calls for IGAD to collaborate with national and international partners in designing and implementing more effective prevention and control programmes. Furthermore, interventions must extend beyond the health sector and improve the livelihood of these populations.  相似文献   
8.
Mycobacterium tuberculosis (Mtb) 38‐kDa antigen is an immunogenic lipoprotein that induces strong T‐cell responses in experimental animals. However, there is limited information on the role of this antigen in human population. In this article, we present the dynamics of pro‐inflammatory (IFN‐γ and TNF‐α) and anti‐inflammatory cytokine (IL‐10) against the 38 kDa in cohorts of pulmonary TB (PTB) patients, household contacts (HHCs), and community controls (CCs) in a high endemic setting. Whole blood assay was used to determine the levels of cytokines in 149 patients, 149 HHCs, and 68 CCs at baseline, 6 months, and 12 months. At baseline, the level of IFN‐γ was significantly (p < 0.0001) higher in CCs and HHCs than in untreated patients. CCs had significantly (p < 0.05) higher level of IFN‐γ than HHCs. There was no significant difference between treated and untreated patients, and there was no significant change in HHCs over 12 months. At baseline, the levels of IL‐10 and TNF‐α were significantly (p < 0.0001) higher in patients than in HHCs and CCs. No significant change was observed between treated patients and untreated patients and HHCs over time. The study shows that IFN‐γ against the 38 kDa discriminates clinical TB from infection and infection from exposure, suggesting its potential for immune protection and diagnosis.  相似文献   
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10.
AIDS and Behavior - This study assessed the HIV prevalence among MSM in the greater Newark New Jersey area including Essex, Hudson, Morris and Union Counties and examined correlates of HIV...  相似文献   
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