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81.
Background: Molecular subtypes of breast cancer have been extensively studied in invasive carcinoma. They were shown to have a different distribution within the various ethnic populations. Few studies have applied the same classification to Ductal Carcinoma in Situ (DCIS). We report the distribution of the molecular breast cancer subtypes in DCIS between African American (AA) and Caucasian American (CA) women, their association with pathological features and outcome. Materials and methods: Tissue microarrays were constructed from paraffin blocks of 94 DCIS cases (67 AA and 27 CA) selected from a cohort of AA and CA patients diagnosed with DCIS between 1996 and 2000; mean age at diagnosis was 61 ± 12 for the AA and 58 ± 11 years for the CA group. TMA blocks were labeled with antibodies for ER, PR, HER2, Ki-67, and CK5/6. The cases were subtyped as Luminal A (ER+ and/or PR+; HER2?), Luminal B (ER+ and/or PR+; HER2+), HER2+ (ER?, PR?; HER2+), basal-like (BL) (ER?, PR?, HER2?; CK5/6+) or unclassified triple negative (UTN) (ER?, PR?, HER2?, CK5/6?). Information on grade, size and follow-up were obtained. Results: (1) Most DCIS cases were Luminal A, comprising 80% of the DCIS cases in AA and 92.6% in CA patients. (2) HER2+, BL and UTN DCIS subtypes were not seen in the CA population, and formed 9% of the DCIS cases in the AA population; these cases were all high grade. (3) In the cases with recurrence (8 AA and 1 CA patients), DCIS was Luminal A in 6 AA and 1 CA and Luminal B in 2 AA patients. Conclusion: The distribution of the molecular subtypes of DCIS did not show a significant difference between the two ethnic groups in our study. In addition, the risk of recurrence might not be higher in the non-luminal subtypes than in Luminal A and B.  相似文献   
82.
A simple and rapid liquid chromatographic method was developed and validated for the determination of triclabendazole with high accuracy and precision within 6 min. Good chromatographic separation was achieved using a CLC Shim‐pack C8 (250 × 4.6 mm, 5 µm particle size) using the mobile phase containing a mixture of 0.02 m phosphate buffer and methanol with a ratio of (20 : 80 v/v) at pH 4.0 was pumped at a flow rate of 1.2 mL/min with fluorescence detection for the first time at 338 nm after excitation at 298 nm. Losartan potassium was used as an internal standard. The method showed good linearity in the ranges of 0.05–2.0 µg/mL with limits of detection and quantification of 14.1 and 42.6 ng/mL, respectively. The suggested method was successfully applied for the analysis of triclabendazole in tablets. The high sensitivity of the method enabled the determination of the studied drug in spiked human plasma with mean percentage of recoveries of 99.79 ± 5.09. Statistical evaluation of the data was performed according to ICH Guidelines. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
83.

Background

Bacteria are frequently cultured from sputum samples of severe asthma patients suggesting a defect in bacterial clearance from the airway. We measured the capacity of macrophages from patients with asthma to phagocytose bacteria.

Methods

Phagocytosis of fluorescently-labelled polystyrene beads, Haemophilus influenzae or Staphylococcus aureus by broncholaveolar lavage alveolar macrophages (AM) and by monocyte-derived macrophages (MDM) from non-asthmatics, mild-moderate and severe asthmatic patients was assessed using fluorimetry.

Results

There were no differences in phagocytosis of polystyrene beads by AMs or MDMs from any of the subject groups. There was reduced phagocytosis of Haemophilus influenzae and Staphylococcus aureus in MDMs from patients with severe asthma compared to non-severe asthma (p < 0.05 and p < 0.01, respectively) and healthy subjects (p < 0.01and p < 0.001, respectively). Phagocytosis of Haemophilus influenzae and Staphylococcus aureus by AM was also reduced in severe asthma compared to normal subjects (p < 0.05). Dexamethasone and formoterol did not suppress phagocytosis of bacteria by MDMs from any of the groups.

Conclusions

Persistence of bacteria in the lower airways may result partly from a reduced phagocytic capacity of macrophages for bacteria. This may contribute to increased exacerbations, airway colonization and persistence of inflammation.  相似文献   
84.
The ant genus Solenopsis Westwood 1840, is recorded for the first time in Saudi Arabia. The worker caste of S. saudiensis n. sp., collected in Riyadh is described and illustrated. This resembles S. cooperi Donisthorpe 1947, and S. kochi Finzi 1936. A revised key to the Arabian species is given together with ecological and biological notes. S. saudiensis n. sp. is identified by the following characters: Anterior clypeal margin with a central pair of stout projecting teeth and a lateral pair of short, broad basal blunt teeth; eyes with two minute facets; funicular segments 2–7 about twice as wide as long; propodeum short and low with the basal face making a continuous arc with the declivity; and petiole as long as broad in dorsal view.  相似文献   
85.
86.

Background  

The combination of mass spectrometry and solution phase amide hydrogen/deuterium exchange (H/D exchange) experiments is an effective method for characterizing protein dynamics, and protein-protein or protein-ligand interactions. Despite methodological advancements and improvements in instrumentation and automation, data analysis and display remains a tedious process. The factors that contribute to this bottleneck are the large number of data points produced in a typical experiment, each requiring manual curation and validation, and then calculation of the level of backbone amide exchange. Tools have become available that address some of these issues, but lack sufficient integration, functionality, and accessibility required to address the needs of the H/D exchange community. To date there is no software for the analysis of H/D exchange data that comprehensively addresses these issues.  相似文献   
87.

Background

CT perfusion (CTP) is used to estimate the extent of ischemic core and penumbra in patients with acute ischemic stroke. CTP reliability, however, is limited. This study aims to identify regions misclassified as ischemic core on CTP, using infarct on follow-up noncontrast CT. We aim to assess differences in volumetric and perfusion characteristics in these regions compared to areas that ended up as infarct on follow-up.

Materials and Methods

This study included 35 patients with >100 mm brain coverage CTP. CTP processing was performed using Philips software (IntelliSpace 7.0). Final infarct was automatically segmented on follow-up noncontrast CT and used as reference. CTP and follow-up noncontrast CT image data were registered. This allowed classification of ischemic lesion agreement (core on CTP: rMTT≥145%, aCBV<2.0 ml/100g and infarct on follow-up noncontrast CT) and misclassified ischemic core (core on CTP, not identified on follow-up noncontrast CT) regions. False discovery ratio (FDR), defined as misclassified ischemic core volume divided by total CTP ischemic core volume, was calculated. Absolute and relative CTP parameters (CBV, CBF, and MTT) were calculated for both misclassified CTP ischemic core and ischemic lesion agreement regions and compared using paired rank-sum tests.

Results

Median total CTP ischemic core volume was 49.7ml (IQR:29.9ml-132ml); median misclassified ischemic core volume was 30.4ml (IQR:20.9ml-77.0ml). Median FDR between patients was 62% (IQR:49%-80%). Median relative mean transit time was 243% (IQR:198%-289%) and 342% (IQR:249%-432%) for misclassified and ischemic lesion agreement regions, respectively. Median absolute cerebral blood volume was 1.59 (IQR:1.43–1.79) ml/100g (P<0.01) and 1.38 (IQR:1.15–1.49) ml/100g (P<0.01) for misclassified ischemic core and ischemic lesion agreement, respectively. All CTP parameter values differed significantly.

Conclusion

For all patients a considerable region of the CTP ischemic core is misclassified. CTP parameters significantly differed between ischemic lesion agreement and misclassified CTP ischemic core, suggesting that CTP analysis may benefit from revisions.  相似文献   
88.
The myrmicine ant genus Carebara is recorded for the first time in Saudi Arabia from the Arabian Peninsula as a whole. A new species Carebara abuhurayrisp. n. is described based on workers collected from Al Bahah region. One of the smallest ant species known to occur in Arabia, Carebara abuhurayri is found in an area inhabited by many ant species including Tetramorium sericeiventre Emery, 1877, Pheidole minuscula Bernard, 1952, Pheidole sp., Monomorium destructor (Jerdon, 1851), Monomorium exiguum (Forel, 1894) and Monomorium sp. and Crematogaster sp.  相似文献   
89.
Sodium dodecyl sulfate–polyacrlyamide gel electrophoresis (SDS–PAGE) was used to assess the purity and molecular weight of the previously purified alkaline keratinase enzyme of Scopulariopsis brevicaulis. The enzyme was homogenous, as seen by a single band of protein, and had an apparent molecular weight of 28.5 kDa. Amino acid profile of the purified keratinase revealed that it was composed of 14 different amino acids with high proportions of glutamic acid (20.86%), alanine (14.52%), glycine (14.21%), leucine (8.59%) and serine (7.81%). The enzyme contained moderate amounts of valine (6.01%), threonine (5.58%) and phenyl alanine (5.22%). The purified enzyme of S. brevicaulis exerted a potent keratinolytic activity and was capable to hydrolyze different keratinaceous materials with highest activity on chicken feathers followed by human nails and human hair.  相似文献   
90.
A new microwave curing system was used to affect crosslinking of cotton fabric with nonformaldehyde finishes, namely, glyoxal, glutaraldehyde and 1,2,3,4 butanetetracarboxylic acid (BTCA). Water soluble chitosan was incorporated in the finishing bath in order to impart antibacterial activity to the fabric in addition to the ease of care characteristics. Glyoxal proved to be the best finish and, hence, it was studied along with the chitosan under a variety of conditions including chitosan concentrations, power and time of microwave curing. Besides the crease recovery and strength properties of the finished fabrics, the latter were also monitored for N%, antibacterial activity and characterized using scanning electron microscope (SEM) and FTIR spectra when compared. With conventional curing system, the microwave curing system was found advantageous in production of cotton fabrics with easy care antibacterial properties without high losses in strength properties.  相似文献   
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