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1.
We report a case of cervical necrotizing fasciitis (CNF) in a female having uncontrolled type II diabetes mellitus. The patient was presented to us after 20 days of preliminary symptoms. The aetiology of microbial inoculation in subdermal tissue was not known. The isolate was Staphylococcus aureus. In spite of the delay in presentation, the patient was successfully treated with combined antimicrobial and surgical intervention.  相似文献   
2.
Objectives: to evaluate the diagnostic value of clinical symptoms and signs in enteric fever and to propose a clinical diagnostic criterion. Design: Prospective observational study Setting: Kathmandu Medical College, Teaching Hospital, Kathmandu, Nepal Materials and methods: febrile patients with clinical diagnosis of enteric fever were included in the study with the aim of confirming diagnosis with blood culture, or bone marrow culture and evaluating the diagnostic accuracy of various clinical signs and symptoms. Results: 64% of the clinically diagnosed cases had blood/ bone marrow culture positive. The diagnostic accuracy of the various symptoms and signs excluding fever was between 42%-75.5%. Majority of the symptom and sign did not have very high diagnostic accuracy. Hence a diagnostic criterion was proposed and clinical features with diagnostic accuracy more than 50% were taken into consideration. Major criteria included fever with diagnostic accuracy of 64%, headache with accuracy of 75.5% and relative bradycardia with an accuracy of 66%. Minor criteria included vomiting, diarrhoea, Splenomegaly, chills and abdominal pain /discomfort with diagnostic accuracy of 57%, 55%, 55%, 53% and 51% respectively. Finally after combination of various major and minor criteria a final diagnostic criterion was proposed having an accuracy of 66% and including both major and minor clinical symptom and sign. Conclusion: clinical diagnosis of enteric fever will be very helpful in a country like ours. Though none of the clinical symptoms and sign have very high diagnostic accuracy a diagnostic criteria may be helpful. Criteria including both major and minor signs and symptoms would be the most appropriate diagnostic tool as it includes the important abdominal symptoms and signs of enteric fever. Key words: enteric fever, clinical features, diagnostic criteria.  相似文献   
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This paper describes the synthesis of enamino carbonyl compounds by the copper(i)-catalyzed coupling of acceptor-substituted diazo compounds and tertiary thioamides. We plan to use this method to synthesize indolizidine (−)-237D analogs to find α6-selective antismoking agents. Therefore, we also performed in silico α6-nAchRs binding studies of selected products. Compounds with low root-mean-square deviation values showed more favorable binding free energies. We also report preliminary pharmacokinetic data on indolizidine (−)-237D and found it to have weak activity at CYP3A4. In addition, as enamino carbonyl compounds are also known for antimicrobial properties, we screened previously reported and new enamino carbonyl compounds for antibacterial, antimicrobial, and antifungal properties. Eleven compounds showed significant antimicrobial activities.

This paper describes the synthesis of enamino carbonyl compounds by the copper(i)-catalyzed coupling of acceptor-substituted diazo compounds and tertiary thioamides.  相似文献   
5.
目的 研究以聚乙二醇-聚己内酯-丙交酯(PEG-CL/LA)为聚合物载体的甲硝唑缓释膜的体外抗菌和药物释放性能,旨在研制一种新型的具有抗菌作用的药物缓释膜。方法 用紫外分光光度法测定5wt%、8wt%及10wt%甲硝唑药膜中药物的体外释放度;选用牙周可疑致病菌具核梭杆菌(Fn)和致龋菌变异链球菌(Sm),采用抑菌圈法研究3种药膜对厌氧菌和兼性厌氧菌的抗菌性能。结果(1)药膜在载药量为5wt%~10wt%时具有较好的缓释性能,药物释放时间随着甲硝唑含量的增加而缩短,3种比例的载药膜的药物释放时间均可达7天以上,其中,5wt%药膜可达10天。(2)随着药物含量增加,抗菌作用逐渐增强,5wt%载药膜对Sm和Fn的抑菌圈直径分别为(8.00±0.16) mm和(8.07±0.09) mm;8wt%载药膜为(10.13±0.19) mm和(11.13±0.09) mm;10wt%载药膜为(12.07±0.09) mm和(19.33±0.94) mm。该药膜对具核梭杆菌的抑制作用强于对变异链球菌的抑制作用。结论 PEG-CL/LA载药膜对牙周致病菌的抑制作用效果明显,且具有良好的药物缓释性能,是一种有望用来辅助治疗牙周疾病的药物膜。  相似文献   
6.
Extramedullary hematopoiesis (EMH) represents tumor-like proliferation of hemopoietic tissue which complicates chronic hemoglobinopathy. Intracranial EMH is an extremely rare occurrence. Magnetic resonance imaging (MRI) offers a precise diagnosis. It is essential to distinguish EMH from other extradural central nervous system tumors, because treatment and prognosis are totally different. Herein, we report the imaging findings of beta-thalassemia in a 13-year-old boy complaining of weakness of left side of the body and gait disturbance; CT and MRI revealed an extradural mass in the right temporoparietal region.  相似文献   
7.
Contact precautions are recommended in hospitals to prevent the transmission of vancomycin-resistant enterococci (VRE); however, there is no clear policy for how long patients should be under contact precautions due to a lack of information on the duration of carriage of these organisms. We conducted a retrospective cohort study to understand the duration of carriage of VRE (by screening of a single stool culture) and associated factors among patients who had been identified with VRE infection and/or colonization since the year 2000 at our health facilities. Of the 345 eligible participants, 136 did not respond, 90 declined to participate, and 16 did not send in the required specimens. Of the 103 remaining participants, 13 were found to have current VRE fecal carriage. The proportion of colonized patients fell from 40% (2/5) in the first year to 23.3% (7/30) in year 4. None of the 40 patients who had VRE detected >4 years prior were found to be colonized at the time of the study. The longest duration of detected VRE positivity was 46.5 months. Univariate analysis revealed that recent exposure to any antibiotics (P = 0.016), multiple antibiotics (P = 0.001), amoxicillin-clavulanic acid (P = 0.021), piperacillin-tazobactam (P = 0.007), glycopeptides (P < 0.001), meropenem (P = 0.007), aminoglycosides (P = 0.021), or fluoroquinolones (P = 0.021), being the index case in a clinical specimen (P = 0.016), and recent hospitalization (P < 0.001) were significantly associated with continued carriage on follow-up. In the surviving outpatients, a significant proportion appeared to clear VRE carriage. Our results suggest that in the absence of recent risk factors, such as hospitalization or antibiotic use, patients with a remote history of colonization (>4 years) may no longer require contact isolation precautions.  相似文献   
8.
Fast axonal transport is characterized by the bidirectional, microtubule-based movement of membranous organelles. Cytoplasmic dynein is necessary but not sufficient for retrograde transport directed from the synapse to the cell body. Dynactin is a heteromultimeric protein complex, enriched in neurons, that binds to both microtubules and cytoplasmic dynein. To determine whether dynactin is required for retrograde axonal transport, we examined the effects of anti-dynactin antibodies on organelle transport in extruded axoplasm. Treatment of axoplasm with antibodies to the p150Glued subunit of dynactin resulted in a significant decrease in the velocity of microtubule-based organelle transport, with many organelles bound along microtubules. We examined the molecular mechanism of the observed inhibition of motility, and we demonstrated that antibodies to p150Glued disrupted the binding of cytoplasmic dynein to dynactin and also inhibited the association of cytoplasmic dynein with organelles. In contrast, the anti-p150Glued antibodies had no effect on the binding of dynactin to microtubules nor on cytoplasmic dynein-driven microtubule gliding. These results indicate that the interaction between cytoplasmic dynein and the dynactin complex is required for the axonal transport of membrane-bound vesicles and support the hypothesis that dynactin may function as a link between the organelle, the microtubule, and cytoplasmic dynein during vesicle transport.  相似文献   
9.

Background

User content posted through Twitter has been used for biosurveillance, to characterize public perception of health-related topics, and as a means of distributing information to the general public. Most of the existing work surrounding Twitter and health care has shown Twitter to be an effective medium for these problems but more could be done to provide finer and more efficient access to all pertinent data. Given the diversity of user-generated content, small samples or summary presentations of the data arguably omit a large part of the virtual discussion taking place in the Twittersphere. Still, managing, processing, and querying large amounts of Twitter data is not a trivial task. This work describes tools and techniques capable of handling larger sets of Twitter data and demonstrates their use with the issue of antibiotics.

Objective

This work has two principle objectives: (1) to provide an open-source means to efficiently explore all collected tweets and query health-related topics on Twitter, specifically, questions such as what users are saying and how messages are spread, and (2) to characterize the larger discourse taking place on Twitter with respect to antibiotics.

Methods

Open-source software suites Hadoop, Flume, and Hive were used to collect and query a large number of Twitter posts. To classify tweets by topic, a deep network classifier was trained using a limited number of manually classified tweets. The particular machine learning approach used also allowed the use of a large number of unclassified tweets to increase performance.

Results

Query-based analysis of the collected tweets revealed that a large number of users contributed to the online discussion and that a frequent topic mentioned was resistance. A number of prominent events related to antibiotics led to a number of spikes in activity but these were short in duration. The category-based classifier developed was able to correctly classify 70% of manually labeled tweets (using a 10-fold cross validation procedure and 9 classes). The classifier also performed well when evaluated on a per category basis.

Conclusions

Using existing tools such as Hive, Flume, Hadoop, and machine learning techniques, it is possible to construct tools and workflows to collect and query large amounts of Twitter data to characterize the larger discussion taking place on Twitter with respect to a particular health-related topic. Furthermore, using newer machine learning techniques and a limited number of manually labeled tweets, an entire body of collected tweets can be classified to indicate what topics are driving the virtual, online discussion. The resulting classifier can also be used to efficiently explore collected tweets by category and search for messages of interest or exemplary content.  相似文献   
10.
ObjectivesTo understand the association between markers of oxidative stress, levels of vascular endothelial growth factor (VEGF), and cell proliferation index in relation to disease progression, clinical stage, and cytologic grade in pathophysiology of prostate carcinoma.Patients and methodsCase control study comprised of 40 prostate carcinoma patients along with 40 age- and sex-matched healthy subjects as controls. Levels of 8-hydroxy-2-deoxy guanosine, protein carbonyl, and malondialdehyde along with total antioxidant status were measured to study the oxidative stress status in the study subjects. Angiogenesis was evaluated by studying the VEGF level and cell proliferation index.ResultsThe levels of markers of oxidative stress along with VEGF and cell proliferation index were found to be significantly higher with significantly decreased levels of antioxidant activity in the study subjects in comparison with healthy controls. The results indicate oxidative stress, angiogenesis, and cell proliferation activity increase progressively with the increase in staging and progression of disease.ConclusionsOxidative stress parameters, angiogenesis, and cell proliferation activity point clearly that with the progression of oxidative stress there is a simultaneous progression of angiogenesis, regulation and control of endothelial cell proliferation in relation to disease progression, clinical stage, and cytologic grade in the pathophysiology of prostate carcinoma.  相似文献   
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