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Kuhns LR  Strouse PJ 《Spine》1999,24(4):339-341
STUDY DESIGN: This radiographic study was designed to attempt to develop standards of facet coverage (overlap) on lateral cervical radiographs during voluntary flexion. OBJECTIVE: To produce normative standards for minimum facet coverage in children. SUMMARY OF BACKGROUND DATA: Previous studies on normative standards of facet coverage have been performed only in adults. METHODS: Thirty-six children with minor trauma had lateral flexion-extension radiographs. A standard filming sequence was used in all. Facet joint overlap at each level was divided by the anteroposterior diameter of the upper adjacent cervical body at each level. RESULTS: On linear regression analysis, these ratios did not vary significantly with age at C2-C3 through C6-C7. Means and standard deviations were determined for C2-C7. CONCLUSIONS: These ratios may prove useful in evaluation of children with possible ligamentous injury.  相似文献   
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Dysfunctional LAD-1 neutrophils and colitis   总被引:3,自引:0,他引:3  
Leukocyte adhesion deficiency 1 (LAD-1) is characterized by absent or dysfunctional beta2 integrin (CD18), leading to defective chemotaxis, adherence, phagocytosis, and bacterial killing. Colitis, except for rare intestinal necrotizing events, is not a well-recognized feature of this immunodeficiency. A case of nonspecific colitis clinically resembling Crohn's disease in a patient with the severe form of LAD-1 (0.5% < CD18) has been previously reported. We describe an adult patient with the moderate form of LAD-1 and chronic colitis characterized by extensive inflammation and ulceration of the right colon and terminal ileum, leading to adhesions and strictures. The chronic colitis described in this article associated with the dysfunctional neutrophils of LAD-1 represents a distinct pathology from the commonly encountered forms of inflammatory bowel disease (IBD). The existence of active IBD in the presence of dysfunctional CD18/CD11(a-b) intercellular adhesion molecules (ICAM-1) interaction is relevant to the proposed targeting of ICAM-1 for the treatment of Crohn's disease.  相似文献   
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Nuclear inheritance of oligomycin resistance in mouse L cells   总被引:2,自引:0,他引:2  
The inheritance of oligomycin resistance was studied in three mouse L-cell mutants, OLI 2, OLI 4, and OLI 14. All three mutants had previously been shown to have oligomycin-resistant mitochondrial ATPase activity. In addition, OLI 14 has DCCD-resistant mitochondrial ATPase activity and an altered DCCD-binding protein. Oligomycin-resistant cells were enucleated and fused with oligomycin-sensitive cells under a variety of selective regimes designed to allow growth of oligomycin-resistant cybrids. No transfer of oligomycin resistance via the cytoplasm of OLI 2, OLI 4, or OLI 14 was detected. In contrast, oligomycin resistance was transferred with the karyoplasts of OLI 14 in karyoplast-cell fusions. Fusions between OLI 14 cells and oligomycin-sensitive cells also produced oligomycin-resistant hybrids. Transfer of oligomycin resistance in the karyoplast-cell and cell-cell fusions was demonstrated at the level of the mitochondrial ATPase. These results indicate that oligomycin resistance in OLI 14 is most likely under nuclear control. Furthermore, nuclear inheritance of oligomycin resistance in a mutant with a modified DCCD-binding protein suggests that the gene for the DCCD-binding protein is encoded in the nucleus of mammalian cells.  相似文献   
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The syndrome of monocytopenia, B-cell and NK-cell lymphopenia, and mycobacterial, fungal, and viral infections is associated with myelodysplasia, cytogenetic abnormalities, pulmonary alveolar proteinosis, and myeloid leukemias. Both autosomal dominant and sporadic cases occur. We identified 12 distinct mutations in GATA2 affecting 20 patients and relatives with this syndrome, including recurrent missense mutations affecting the zinc finger-2 domain (R398W and T354M), suggesting dominant interference of gene function. Four discrete insertion/deletion mutations leading to frame shifts and premature termination implicate haploinsufficiency as a possible mechanism of action as well. These mutations were found in hematopoietic and somatic tissues, and several were identified in families, indicating germline transmission. Thus, GATA2 joins RUNX1 and CEBPA not only as a familial leukemia gene but also as a cause of a complex congenital immunodeficiency that evolves over decades and combines predisposition to infection and myeloid malignancy.  相似文献   
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Young transgender women (YTW) are disproportionately affected by HIV, however, little is known about the factors associated with HIV infection and treatment engagement. We examined correlates of HIV infection and the steps of the HIV treatment cascade, specifically, being aware of their HIV infection, linked to care, on ART, and adherent to ART. We analyzed the baseline data of Project LifeSkills, a randomized control trial of sexually active YTW recruited from Chicago, Illinois and Boston, Massachusetts. We conducted multivariable Poisson regressions to evaluate correlates of HIV infection and the steps of the HIV treatment cascade. Nearly a quarter (24.7%) of YTW were HIV-infected. Among HIV-infected YTW, 86.2% were aware of their HIV status, 72.3% were linked to care, 56.9% were on ART, and 46.2% were adherent to ART. Having avoided healthcare due to cost in the past 12 months and not having a primary care provider were associated with suboptimal engagement in HIV care. Our results suggest that improving linkage and retention in care by addressing financial barriers and improving access to primary care providers could significantly improve health outcomes of YTW as well as reduce forward transmission of HIV.  相似文献   
39.
Transgender women are at high risk of HIV infection, with younger transgender women (YTW) particularly vulnerable. Pre-Exposure Prophylaxis (PrEP) has shown efficacy in reducing HIV acquisition, but little is known about PrEP indication or initiation among YTW. Baseline data from 180 YTW age 18–29 years enrolled in Project LifeSkills, an on-going HIV prevention intervention for YTW, were analyzed to examine factors associated with PrEP indication. The sample (mean age = 23.4, SD = 3.2) was comprised largely of women of color (69 %) and of low socioeconomic status (71 % unemployed). Overall, 62 % met criteria for PrEP indication, but only 5 % reported ever taking PrEP. Factors associated with increased odds of PrEP indication were: PrEP interest (aOR 3.24; 95 % CI 1.44, 7.33), number of recent anal sex partners (aOR 1.23; 95 % CI 1.04, 1.46), and lower collective self-esteem scores (aOR 0.67; 95 % CI 0.47, 0.94). Despite high levels of PrEP indication, there remain low levels of PrEP awareness and uptake among YTW.  相似文献   
40.
Since the mid-1990s, a steady increase in the occurrence of itraconazole-resistant Aspergillus fumigatus isolates has been observed in clinical contexts, leading to therapeutic failure in the treatment of aspergillosis. This increase has been predominantly linked to a single allele of the cyp51A gene, termed TR/L98H, which is thought to have arisen through the use of agricultural azoles. Here, we investigated the current epidemiology of triazole-resistant A. fumigatus and underlying cyp51A mutations in clinical samples in Germany. From a total of 527 samples, 17 (3.2%) showed elevated MIC0 values (the lowest concentrations with no visible growth) for at least one of the three substances (itraconazole, voriconazole, and posaconazole) tested. The highest prevalence of resistant isolates was observed in cystic fibrosis patients (5.2%). Among resistant isolates, the TR/L98H mutation in cyp51A was the most prevalent, but isolates with the G54W and M220I substitutions and the novel F219C substitution were also found. The isolate with the G54W substitution was highly resistant to both itraconazole and posaconazole, while all others showed high-level resistance only to itraconazole. For the remaining six isolates, no mutations in cyp51A were found, indicating the presence of other mechanisms. With the exception of the strains carrying the F219C and M220I substitutions, many itraconazole-resistant strains also showed cross-resistance to voriconazole and posaconazole with moderately increased MIC0 values. In conclusion, the prevalence of azole-resistant A. fumigatus in our clinical test set is lower than that previously reported for other countries. Although the TR/L98H mutation frequently occurs among triazole-resistant strains in Germany, it is not the only resistance mechanism present.  相似文献   
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