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111.
112.
T-cell large granular lymphocytic leukemia and chronic lymphoproliferative disorder of natural killer cells are intriguing entities between benign and malignant lymphoproliferation. The molecular pathogenesis has partly been uncovered by the recent discovery of somatic activating STAT3 and STAT5b mutations. Here we show that 43% (75/174) of patients with T-cell large granular lymphocytic leukemia and 18% (7/39) with chronic lymphoproliferative disorder of natural killer cells harbor STAT3 mutations when analyzed by quantitative deep amplicon sequencing. Surprisingly, 17% of the STAT3-mutated patients carried multiple STAT3 mutations, which were located in different lymphocyte clones. The size of the mutated clone correlated well with the degree of clonal expansion of the T-cell repertoire analyzed by T-cell receptor beta chain deep sequencing. The analysis of sequential samples suggested that current immunosuppressive therapy is not able to reduce the level of the mutated clone in most cases, thus warranting the search for novel targeted therapies. Our findings imply that the clonal landscape of large granular lymphocytic leukemia is more complex than considered before, and a substantial number of patients have multiple lymphocyte subclones harboring different STAT3 mutations, thus mimicking the situation in acute leukemia.  相似文献   
113.
Human immunodeficiency virus (HIV) is a causative agent of AIDS while Mycobacterium tuberculosis causes human tuberculosis, independently. HIV and M.?tuberculosis co-infection is an intriguing immunopathological phenomenon. The effect is not simply an additive but far more than that. This review gives an account of how various host and pathogen specific factors interplay to make this co-infection one of the worst co-infection, rightly named as medical "double jeopardy". We have attempted to recount some of the immune mechanisms how both these pathogens disturb the balance of host immune system resulting into defects in the host phagocytic response, leading to apoptosis and chemokine dysregulation. The HIV provides protected shelter to the M.?tuberculosis and M.?tuberculosis provides conducive atmosphere through the interplay of various chemokines. We also touch upon the treatment associated complications like Immune reconstitution inflammatory syndrome (IRIS) these patients face.  相似文献   
114.
Background: Peritoneal dialysis (PD) is an established treatment modality for end-stage renal disease (ESRD). Peritonitis remains a serious complication in PD patients and an important cause of drop-out from the program. Types of pathogens and their drug resistance patterns may determine the outcome of peritonitis. The present study was undertaken to determine the microbiology of peritonitis in PD patients, antibiotic resistance in commonly isolated bacterial pathogens and clinical outcomes.♦ Method: We enrolled 211 patients with ESRD undergoing PD who developed peritonitis during 2002 to 2011. PD fluids were cultured and antibiotic susceptibility test of the bacterial isolates was performed.♦ Result: A total of 303 peritonitis episodes with an overall incidence of 0.41 episodes per patient-year were recorded. Gram-positive, gram-negative, fungi, Mycobacterium tuberculosis and ≥ 2 organisms were isolated from 102 (33.7%), 89 (29.4%), 41 (13.5%), 11 (3.6%) and five (1.6%) episodes respectively; 55 (18.2%) episodes were culture negative. Coagulase-negative Staphylococcus spp. (CONS) was the most common isolate. Catheter loss and hospital admission in gram-negative peritonitis were significantly higher than in gram-positive peritonitis (36/89 (40.4%) vs 20/102 (19.6%), p < 0.001; and 56/89 (62.9%) vs 42/102 (41.2%), p = 0.004 respectively). Antibiotic susceptibility tests showed 54.3% of Enterobacteriaceae isolates were extended spectrum β-lactamase (ESBL) producers, 23.5% of Acinetobacter species and 11.5% of Pseudomonas aeruginosa were metallo-β-lactamase (MBL) producers; 15.4% of enterococci and 28.6% of staphylococci were resistant to vancomycin and methicillin respectively. Mortality was significantly higher in patients having peritonitis due to vancomycin-resistant enterococci, ESBL- and MBL-producing bacteria.♦ Conclusion: Emerging antimicrobial resistance calls for prompt diagnosis and aggressive empiric therapy based on the local sensitivity data.  相似文献   
115.
Although mandatory fortification of oil with vitamin A is efficacious, its effectiveness can be compromised by suboptimal compliance to standards. In this study, we assessed (1) the availability of oil brands across the eight divisions of Bangladesh, (2) fortification quality (the extent to which vitamin A content is aligned with fortification standards) of oil brands and producers and (3) the market volume represented by available edible oil types. We visited different retail outlets in rural and urban market hubs to ascertain available oil brands and bulk oil types and collected samples. We used high-performance liquid chromatography to quantify average vitamin A content and compared them to the national oil fortification standards. Among the 66 packaged brands analyzed, 26 (39%) were not fortified, and 40 (61%) were fortified, with 28 (42%) fortified above the standard vitamin A minimum. Among the 41 bulk oil type composites analyzed, 24 (59%) were not fortified, and 17 (41%) were fortified, with 14 (34%) fortified below and 3 (7%) fortified above the standard minimum. Vitamin A fortification is high for packaged and branded edible oil but low for oil sold in unbranded, loose form. As bulk oil makes up a large proportion of the oil market volume, this means the majority of the oil volume available to the population is either not (25%) or fortified below the standard requirement (39%). Regulatory inspections of producers selling bulk oil should be prioritized to support and incentivize the industry to make all oil traceable and fortified to standard.  相似文献   
116.
The 5-year undergraduate medical curriculum at Aga Khan University integrates basic sciences with clinical and community health sciences. Multimodal strategies of teaching and learning, with an emphasis on problem-based learning, are utilized to equip students with knowledge, skills, behaviours, attitudes and values necessary for a high-calibre medical graduate. Bioethics teaching was introduced in the medical curriculum in 1988 and has since undergone several changes. In 2009, a multidisciplinary voluntary group began review of undergraduate bioethics teaching and invested over 350 man-hours in curricular revision. This involved formulating terminal objectives, delineating specific objectives and identifying instructional methodologies and assessment strategies appropriate for the contents of each objective. Innovative strategies were specially devised to work within the time constraints of the existing medical curriculum and importantly, to increase student interest and engagement. The new bioethics curriculum is designed to be comprehensive and robust, and strives to develop graduates who, in addition to being technically skilled and competent, are well-versed in the history and philosophy of ethics and bioethics and are ethical in their thinking and practice, especially in the context of a developing country like Pakistan where health indicators are among the worst in the region, and clinical practices are not effectively regulated to ensure quality of care.  相似文献   
117.

Objectives/hypothesis

To describe the incidence and determinants of survival of patients with nasopharyngeal adenocarcinoma between the years of 1973 to 2012 using the Surveillance, Epidemiology, and End Result (SEER) database.

Study design

Retrospective cohort study using a national database.

Methods

The SEER registry was utilized to calculate survival trends for patients with nasopharyngeal adenocarcinoma between 1973 and 2012. Patient data was then analyzed with respect to histopathology, age, sex, race, stage, grade, and treatment modalities (surgery and radiation therapy). Overall (OS) and disease-specific survival (DSS) were calculated.

Results

A total of 148 cases of nasopharyngeal adenocarcinoma were identified. The cohort was composed of 54.7% males. The mean age at diagnosis was 59.0 years. The median OS was 60.6 months. 59.4% of cases were treated with surgery, while 64.1% received radiation therapy. OS at 2, 5, and 10 years was 63%, 49%, and 36%, respectively. There was no significant difference in OS and DSS between adenocarcinoma of the nasopharynx versus the sinonasal tract (p > 0.05). On univariate analysis, younger age, surgery, surgery and radiation, and lower tumor grade were associated with improved OS and DSS, while papillary subtype, lower stage, and no distant metastasis were associated with improved OS alone (all p < 0.05).

Conclusions

Nasopharyngeal adenocarcinoma is an extremely rare malignancy with poor prognosis, with the exception of the papillary subtype. Age, grade, and surgical therapy are predictors of survival.  相似文献   
118.
Acute leukaemia (AL) is a critical neoplasm of white blood cells. Diagnosing AL requires bone marrow puncture procedure, which many patients do not consent to for it is invasive. Hence sensitive and specific early diagnostic biomarkers are essential for non‐invasive diagnosis, new therapeutics and improving the disease prognosis. To differentiate the metabolic alterations associated with acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML), we investigated serum of ALL and AML patients in comparison with two controls using gas chromatography coupled with triple quadrupole tandem mass spectrometry and multivariate statistical analysis. Twenty seven out of 1425 metabolites were found differentiative among ALL, AML, aplastic anaemia (APA) patients and healthy control using p‐value ≤ 0.001. ALL is the most dissimilar group from other three groups as in hierarchical clustering showed 72.1% dissimilarity. Model generation using PLSDA gave an overall accuracy of 91.9%. This study helps in metabolic fingerprinting of control and disease serum at high significance levels and could be used for early diagnosing of AL. Based on pathways analysis, fatty acid metabolism is deregulated in patients with AL and may represent an underlying metabolic pathway associated with disease progression. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
119.
Molecular mimicry between Campylobacter jejuni lipopolysaccharide and host gangliosides induces an immune response leading to axonal damage and Guillain-Barré syndrome (GBS). TLR polymorphisms are associated with many autoimmune diseases. The role of the TLR4 gene in GBS susceptibility largely remains unknown. We investigated TLR4 polymorphism in GBS. One hundred and twenty GBS patients and 150 healthy controls were included. TLR4 (Asp299Gly and Thr399Ile) genes were studied by PCR-RFLP. TLR4 (Asp299Gly) polymorphism was significantly associated with GBS (p, 0.045; OR, 8.75; 95% CI, 1.05–72.88); only acute motor axonal neuropathy (AMAN) was associated with Gly299Gly homozygote (p, 0.027; OR, 12.40; 95% CI, 1.33–115.77) and Thr399Ile (p, 0.019; OR, 3.42; 95% CI, 1.22–9.54) heterozygote, and TLR4–399Ile allele (p, 0.045; OR, 2.63; 95% CI, 1.02–6.75) compared to controls. In conclusion, TLR4 (Asp299Gly) polymorphism is associated with an increased susceptibility to GBS. Besides Asp299Gly, AMAN subtype is also associated with Thr399Ile polymorphism.  相似文献   
120.
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