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41.
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Background: Due to Russia and Ukraine’s key roles in supplying cereals and oilseeds, the Russia–Ukraine war intensifies the current food availability and price challenges in Lebanon, which is a major wheat importer. Given these constraints, we conducted this study to assess the prevalence and correlates of food insecurity, low dietary diversity (DD), unhealthy dietary patterns, and the shifts in households’ food-related habits in response to the Russia–Ukraine war among a representative sample of Lebanese household’s members aged 18 years and above (N = 914). Methods: Data were collected between June and July 2022 using self-administered questionnaires; Results: Findings showed that nearly half of the households consume an undiversified diet (46%), and 55.3% ate fewer than two meals per day. The prevalence of food insecurity among Lebanese households was 74%, with one in every four households being severely food insecure. In addition, the majority of households’ members went out shopping and purchased food less than the pre-war period (68.7% and 70.3%, respectively). Furthermore, almost 68.3% of households’ members highlighted price increases for cereal products, which were the least available and most stocked items. Findings obtained through binary logistic regression also showed that food insecurity was two times higher among households with low monthly income, 35% higher among females, and three times higher among married participants; Conclusions: The impact of the Russia–Ukraine conflict on food security in Lebanon requires a systems-thinking approach as well as international effort to understand the challenges and find solutions to minimize the war’s negative effects.  相似文献   
43.
Immunoprotective tumor antigens of experimental tumors are selectively extracted by 1-butanol. Human organ-specific cancer neoantigens (OSNs) are tumor substances in cancer extracts to which patients with cancer of the same organ respond in the in vitro assay of leukocyte adherence inhibition. Here we determined whether OSNs as measured by leukocyte adherence inhibition assay are also selectively solubilized by 2.5% (v/v) 1-butanol. Butanol extracts of live tissue-cultured human cancer cells as well as extracts of primary breast cancer contained OSNs as determined by leukocyte reactivity in leukocyte adherence inhibition. With two-phase butanol, OSN activity was recovered in the aqueous and not in the organic phase, indicating that OSN is not a lipoprotein. The butanol-soluble OSN, whether allogeneic or autologous, was recognized by the T4 subset of T-cells in association with Class II major histocompatibility complex antigens of monocytes. Autologous OSN was extracted from membrane preparations of autologous primary cancer. Butanol extracts contained the previously identified Mr 40,000 protein OSN. Butanol removed about 50% of the Mr 40,000 protein OSN from live cancer cell membranes. Probably because of residual OSN in the membrane fragments and the ability of OSN to reassociate with the membrane, the T8 subset of pure T-cells responded positively to autologous cancer extracts. Passage of the autologous extract through an anti-Class I major histocompatibility complex antigen affinity column but not through a control affinity column negated the activity of the extract with pure autologous T-cells. The results indicate that human OSNs share with immunoprotective tumor antigens of experimental tumors the unique physicochemical property of being selectively extracted by 2.5% butanol.  相似文献   
44.
Soluble lung tumor activity as determined by LAI2 was enriched by physicochemical methods from chemically - defined spent medium of a lung cancer cell line (NCI-H69). To identify the polypeptide carrying the antigenic determinant, splenic lymphocytes of BALB/c mice were immunized with the enriched isolate and hybridized with mouse plasmacytoma cells. Eight hybrids were cloned successfully and produced MAbs that immunoprecipitated principally a single chain of Mr 40,000 (p40) as well as minor chains of Mr 25,000 (p25) and Mr 13,000 (p13) which were probably degradation products of p40. On 2D gels, p40 was composed of 7 spots with a p1 of 6.3 to 7.6, which was not altered by neuraminidase digestion. Affinity chromatography with MAb anti-p40 absorbed p40 and LAI activity. The bound and recovered fraction was enriched for p40 and LAI activity. Affinity-purified p40 also contained the previously identified p25 and p13 as well as a Mr 32,000 peptide (p32). MAb anti-p40 was directed to a common framework determinant on p40 since MAb anti-p40 bound to cancer cells from other organs. The comparatively lung cancer organ-specific determinant recognized by leukocytes from lung cancer patients was not recognized by the MAb. Affinity-purified p40 triggered LAI for leukocytes from patients with lung cancer but not for leukocytes from control subjects or patients with colon cancer or malignant melanoma in rigorous blind testing. Crossreactivity was observed with leukocytes from patients with breast cancer. LAI activity of affinity-purified p40 seems unlikely to result from an unidentified impurity. Thus a p40 molecule has been purified that is expressed on the membranes of lung cancer cells and triggers immunologically-mediated LAI.  相似文献   
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A murine model for the immunotherapy of head and neck cancer was established. The AT-84 tumor, a spontaneously arising oral squamous cell tumor of C3H mice, was evaluated for susceptibility to lymphokine-activated killer (LAK) cells. In vitro chromium-release assays demonstrated that AT-84 is sensitive to LAK-cell-mediated killing. Furthermore, in vivo experiments employing a lung metastasis model demonstrated a 50% reduction in the number of metastases in LAK-cell-treated mice as compared with untreated controls (P2=.001). These experiments showed that AT-84 is an appropriate model for the immunotherapy of head and neck cancer. This model should be invaluable for further study of the mechanisms involved in immune-mediated therapy of head and neck cancer.  相似文献   
47.
Although bone fragility may already be present at diagnosis of pediatric acute lymphoblastic leukemia (ALL), routine performance of dual-energy X-ray absorptiometry (DXA) in every child is not universally feasible. The aim of this study was to develop and validate a risk prediction model for low lumbar spine bone mineral density (LS BMD Z-score ≤ −2.0) at diagnosis, as an important indicator for fracture risk and further treatment-related BMD aggravation. Children with ALL (4–18 years), treated according to the Dutch Childhood Oncology Group protocol (DCOG-ALL9; model development; n = 249) and children from the Canadian Steroid-Associated Osteoporosis in the Pediatric Population cohort (STOPP; validation; n = 99) were included in this study. Multivariable logistic regression analyses were used to develop the prediction model and to confirm the association of low LS BMD at diagnosis with symptomatic fractures during and shortly after cessation of ALL treatment. The area under the receiver operating characteristic curve (AUC) was used to assess model performance. The prediction model for low LS BMD at diagnosis using weight (β = −0.70) and age (β = −0.10) at diagnosis revealed an AUC of 0.71 (95% CI, 0.63–0.78) in DCOG-ALL9 and 0.74 (95% CI, 0.63–0.84) in STOPP, and resulted in correct identification of 71% of the patients with low LS BMD. We confirmed that low LS BMD at diagnosis is associated with LS BMD at treatment cessation (OR 5.9; 95% CI, 3.2–10.9) and with symptomatic fractures (OR 1.7; 95% CI, 1.3–2.4) that occurred between diagnosis and 12 months following treatment cessation. In meta-analysis, LS BMD at diagnosis (OR 1.6; 95% CI, 1.1–2.4) and the 6-month cumulative glucocorticoid dose (OR 1.9; 95% CI, 1.1–3.2) were associated with fractures that occurred in the first year of treatment. In summary, a prediction model for identifying pediatric ALL patients with low LS BMD at diagnosis, as an important indicator for bone fragility, was successfully developed and validated. This can facilitate identification of future bone fragility in individual pediatric ALL patients. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
48.
Improving knowledge about breast cancer etiology is crucial in order to propose prevention strategies for this pathology. Gut microbiota is involved in numerous physiopathological situations including cancers. Although its potential involvement in breast cancer through the alteration of the enterohepatic circulation of estrogens and/or the metabolism of phytoestrogens has been discussed for some time, it remains to be demonstrated. The present study seeks to strengthen this hypothesis by identifying possible links between the fecal microbiota composition and clinical characteristics in breast cancer patients. Bacterial DNA was extracted from the feces of 31 patients with early-stage breast cancer and amplified by real-time polymerase chain reaction (qPCR), targeting 16S rRNA sequences specific to bacterial groups, and then analyzed in relation to clinical characteristics. The absolute numbers of total bacteria and of three bacterial groups (Firmicutes, Faecalibacterium prausnitzii, and Blautia) differed significantly according to the patient's body mass index. The percentage and the absolute numbers of certain bacterial groups, namely C. coccoides, F. prausnitzii, and Blautia, differed significantly according to the clinical stages and the histoprognostic grades. Our study highlighted that intestinal microbiota composition in these patients differs according to clinical characteristics and BMI. Further studies are required to clarify the link between breast cancer and intestinal microbiota.  相似文献   
49.
Background

Microscopic unilateral laminotomy for bilateral decompression (ULBD) is a minimally invasive technique used in the treatment of lumbar spinal stenosis and could limit spinal instability and be associated with better clinical outcomes. However, there is ongoing debate regarding its utility compared to conventional laminectomy (CL). The primary objective was to collate and describe the current evidence base for ULBD, including perioperative parameters, functional outcomes, and complications. The secondary objective was to identify operative techniques.

Methods

A scoping review was conducted between January 1990 and August 2022 according to the PRISMA extension for scoping reviews (PRISMA-ScR) guidelines. Major databases were searched for full text English articles reporting on outcomes following microscopic unilateral laminotomy in patients with lumbar spinal stenosis.

Results

Seventeen articles met the inclusion criteria. Two studies were randomised controlled trials. Two studies were prospective data collection and the rest were retrospective analysis. Three studies compared ULBD with CL. ULBD preserves the osteoligamentous complex and may be associated with shorter operative time, less blood loss, and similar clinical outcomes when compared to CL.

Conclusion

This review highlights that ULBD aims to minimise disruption to the normal posterior spinal anatomy and may have acceptable clinical outcomes. It also highlights that it is difficult to draw valid conclusions given there are limited data available as most studies identified were retrospective or did not have a comparator group.

  相似文献   
50.
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