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81.
We present a case of a 79-year-old female with a history of pain at the right groin for 9 days. Computer tomography of the pelvis showed herniation of the appendix through the obturator canal with a huge abscess surrounding the right hip joint. Laparotomy was performed and histopathology confirmed a perforated necrotic tip of the herniated appendix. An obturator hernia is a rare hernia of the pelvic floor. It is most common in old, emaciated, multiparous women and can cause groin pain with extension to the medial aspect of the thigh. In case of incarceration of bowel, patients also present with obstruction. Isolated incarceration of the appendix, however, does not cause obstruction. The diagnosis of an obturator hernia is often delayed, due to a non-specific clinical presentation. CT scan may offer the clue to the correct diagnosis and should be performed in case of a possible obturator hernia.  相似文献   
82.
The pharmacokinetic (PK) profiles of von Willebrand factor (VWF) /factor VIII (FVIII) concentrates are important for treatment efficacy and safety of von Willebrand disease (VWD) patients. This prospective, head-to-head, randomised crossover study compared the PK profile of a new, high purity, human plasma-derived (pd)VWF/FVIII concentrate, Wilate, with the PK profile of an intermediate purity (pd)VWF/FVIII concentrate, Humate-P, in VWD patients. Subjects with inherited VWD were randomised to a single intravenous dose (40 IU/kg VWF ristocetin cofactor activity [VWF:RCo]) of Wilate or Humate-P in Period 1, and switched to the other study drug in Period 2. Each period was preceded by a washout time of ≥ 7 days. Coagulation factor parameters were analysed at multiple time-points. Of 22 randomised subjects, 20 had evaluable PK profiles, which indicated comparability for VWF antigen and VWF:RCo between Wilate and Humate-P. The reported VWF:RCo average and terminal t1/2 of 10.4 and 15.8 hours (h), respectively, for Wilate and 9.3 h and 12.8 h for Humate-P, were not statistically different. Also, the mean VWF:RCo in vivo recoveries (Wilate 1.89, Humate-P 1.99 IU/dl per IU/kg) were similar between the two replacement therapies. Wilate showed parallel decay curves for VWF:RCo and FVIII clotting activity (FVIII:C) over time, while FVIII:C of Humate-P displayed a plateau between 0 and 12-24 h. This study demonstrated bioequivalent PK properties for VWF between Wilate and Humate-P. The PK profile of Wilate, combined with the 1:1 VWF/FVIII ratio, theoretically should facilitate dosing and laboratory monitoring of VWF replacement to prevent bleeding in individuals with VWD.  相似文献   
83.
84.
Arthropod-borne diseases such as malaria and dengue virus afflict billions of people worldwide imposing major economic and social burdens. Control of such pathogens is mainly performed by vector management and treatment of affected individuals with drugs. The failure of these conventional approaches due to emergence of insecticide-resistant insects and drug-resistant parasites demonstrate the need of novel and efficacious control strategies to combat these diseases. Genetic modification (GM) of mosquito vectors to impair their ability to be infected and transmit pathogens has emerged as a new strategy to reduce transmission of many vector-borne diseases and deliver public health gains. Several advances in developing transgenic mosquitoes unable to transmit pathogens have gained support, some of them attempt to manipulate the naturally occurring endogenous refractory mechanisms, while others initiate the identification of an exogenous foreign gene which disrupt the pathogen development in insect vectors. Heterologous expression of transgenes under a native or heterologous promoter is important for the screening and effecting of the transgenic mosquitoes. The effect of the transgene on mosquito fitness is a crucial parameter influencing the success of this transgenic approach. This review examines these two aspects and describes the basic research work that has been accomplished towards understanding the complex relation between the parasite and its vector and focuses on recent advances and perspectives towards construction of transgenic mosquitoes refractory to vector-borne disease transmission.  相似文献   
85.
86.
Objective To assess the sensitivity and specificity of MRI criteria in the differentiation between malignant peripheral nerve sheath tumors (MPNST) and non-neurogenic malignant soft-tissue tumors (MSTT).Design and patients MRI examinations of 105 patients with pathologically proven malignant soft-tissue lesions (35 MPNST and 70 MSTT) were retrospectively reviewed, the reviewers being unaware of the pathological diagnosis. Using a standardized protocol, the tumors were evaluated for multiple parameters regarding morphology and appearance on different sequences before and after gadolinium contrast administration (location, distribution, delineation, homogeneity, size, shape, relationship to bone and neurovascular bundle, intralesional hemorrhage, necrosis, perilesional edema, lymphangitis and signal intensities). Results were compared using a chi-square or Fisher’s exact test.Results MRI findings suggestive of MPNST (p<0,05) were intermuscular distribution, location on the course of a large nerve, nodular morphology, and overall non-homogeneity on T1-weighted images, T2-weighted images and T1-weighted images after gadolinium contrast injection. MRI findings in favor of MSTT were intramuscular distribution, ill-delineated appearance of more than 20% of the lesion’s circumference, and presence of intralesional blood vessels, perilesional edema and lymphangitis. There is no significant difference for degree and pattern of enhancement after gadolinium contrast injection, nor for presence of bone involvement or cystic or necrotic areas.Conclusion MRI provides several features that contribute to the differentiation between MPNST and non-neurogenic malignant soft-tissue tumors. MRI findings suggestive of MPNST should be helpful to pathologists in the strategy for further examination.  相似文献   
87.

Objective

During the ESSR 2011 Research Committee Meeting, the duration of intellectual property of a research proposal was discussed. A duration of 2 years from idea to publication was suggested. The purpose of this study was to evaluate how many ESSR 2008 and 2009 scientific abstracts were PubMed cited in print within 2 years of the congress.

Materials and methods

In September of 2011, two researchers independently performed a literature search using author names and title words of all ESSR 2008 and 2009 scientific abstracts published in Skeletal Radiology. In case of similarity or doubt, a senior reviewer made the final decision. Publication details were recorded and analyses were performed in Microsoft Excel (Microsoft, Redmond, WA, USA).

Results

Until September of 2011, 62 out of 137 ESSR 2008 and 2009 scientific abstracts (45 %) were PubMed cited in print [2008:34/73(47 %); 2009:28/64(44 %)]. 54 out of 137 abstracts (39 %) were PubMed cited in print within 2 years of the congress [2008:30/73(41 %); 2009:23/64(36 %)] including eight out of 137 abstracts (6 %), which were already published before the congress [2008:4/73(5 %); 2009:4/64(6 %)]. The top-ranking journal in absolute numbers of publications was Skeletal Radiology. The top publishing country was the United Kingdom. Study sample size and first author position between abstract and publication did not change in the majority.

Conclusions

Thirty-nine percent of ESSR 2008 and 2009 scientific abstracts were published within 2 years of the congress including 6 % that were already PubMed cited in print before the congress.  相似文献   
88.

Purpose

The aim of this prospective study was to compare routine MRI scans of the knee at 1.5 and 3 T obtained in the same individuals in terms of their performance in the diagnosis of cartilage lesions.

Methods

One hundred patients underwent MRI of the knee at 1.5 and 3 T and subsequent knee arthroscopy. All MR examinations consisted of multiplanar 2D turbo spin-echo sequences. Three radiologists independently graded all articular surfaces of the knee joint seen at MRI. With arthroscopy as the reference standard, the sensitivity, specificity, and accuracy of 1.5- and 3-T MRI for detecting cartilage lesions and the proportion of correctly graded cartilage lesions within the knee joint were determined and compared using resampling statistics.

Results

For all readers and surfaces combined, the respective sensitivity, specificity, and accuracy for detecting all grades of cartilage lesions in the knee joint using MRI were 60, 96, and 87 % at 1.5 T and 69, 96, and 90 % at 3 T. There was a statistically significant improvement in sensitivity (p < 0.05), but not specificity or accuracy (n.s.) for the detection of cartilage lesions at 3 T. There was also a statistically significant (p < 0.05) improvement in the proportion of correctly graded cartilage lesions at 3 T as compared to 1.5 T.

Conclusion

A 3-T MR protocol significantly improves diagnostic performance for the purpose of detecting cartilage lesions within the knee joint, when compared with a similar protocol performed at 1.5 T.

Level of evidence

III.  相似文献   
89.
As per WHO recommendations, measles vaccine is administered at the age of 9 months which is based on studies demonstrating seroconversion (from positive to negative) at this age. However this contention may not hold good in preterm babies since they may have lower initial levels of passively transferred IgG antimeasles antibodies of maternal origin. To explore this possibility, 50 preterm babies (gestational age less than 37 weeks) were studied for antimeasles antibodies. Serum samples were collected at birth and then at 3 months and 5 months of age in all the cases. Antimeasles antibody assay was done in all the serum samples using ELISA kits. At birth 32% of infants were positive for antimeasles antibodies whereas 60% were weakly positive and 8% were negative. At 3 months of age 50% were sero negative, 2% positive and 40% weakly positive. The sero negativity was found to be 98% at 5 months with only 2% remaining positive. Since seroconversion is seen to occur in this vast majority of preterm infants at the age of 5 months, antimeasles vaccine should be administered at this age to this subset of more vulnerable babies.KEY WORDS: Antimeasles antibodies, Preterm babies, Seroconversion  相似文献   
90.
The applicability of a low pH volatile electrolyte for fast analysis of benzodiazepines with CE-MS was investigated. The electrolyte is based on a commercially available CEofix buffer system that produces a substantial and highly reproducible electroosmotic flow through a dynamic double coating principle. The system was first evaluated with a mixture of benzodiazepine standards in CE-DAD and the electrolyte composition was further optimized for CE-MS. The LOD for the six selected benzodiazepines with CE-MS was ca. 100 ppb, except for diazepam, for which the LOD was lower than 50 ppb. RSDs varied from 0.51 to 1.02% (n = 7) for migration times and from 4.75 to 11.80% (n = 7) for peak areas. The method was successfully applied to the analysis of a spiked urine sample after solid-phase extraction (SPE). CE-MS2 was performed on a standard mixture.  相似文献   
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