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A. Sabbah  S. Hassoun  J. Le  Sellin  C. Andre  H. Sicard 《Allergy》1994,49(5):309-313
Fifty-eight patients with well-documented history of seasonal rhinoconjunctivitis caused by grass pollens were allocated randomly on a double-blind basis to receive either sublingual therapy with a solution of purified, standardized allergen preparation (Stallergenes) or a matched placebo for 17 weeks. The assessment of the effect of oral immunotherapy, done with drops of five-grass allergen extract, was on the clinical symptoms and on the medication score of the authorized rescue treatments. The actively treated patients had significantly (P<0.05 to P<0.01) fewer symptoms of rhinitis (sneezing and rhinorrhea) and of conjunctivitis (redness and tears) during the pollen season than the placebo group. Consumption of nasal solution of sodium cromoglycate and of betamethasone and dexchlorpheniramine was significantly less in the desensitized group (P<0.01). Side-effects were negligible. This study concludes that perlingual immunotherapy with grass pollen extract in grass-pollen-sensitive seasonal hay fever and conjunctivitis patients is effective, easy to perform, inexpensive, and safe.  相似文献   
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Inter-species variation of schistosome 28-kDa glutathione S-transferases.   总被引:8,自引:0,他引:8  
The 28-kDa glutathione S-transferase from Schistosoma mansoni (Sm28GST) is a candidate vaccine antigen. To evaluate the antigenic and phylogenetic variations between the 28-kDa GSTs from 4 species of schistosome, we have cloned and sequenced the 28-kDa GSTs from Schistosoma haematobium (Sh28GST) and Schistosoma bovis (Sb28GST). Sb28GST and Sh28GST are more similar to each other (97%) than to Sm28GST (90%) and particularly to the 28-kDa GST from Schistosoma japonicum (Sj28GST, 77%). Antisera directed against the major Sm28GST epitopes revealed differences in the recognition of the 28-kDa GSTs from the other schistosome species suggesting that these regions have been subjected to evolutionary pressure. The consequences of such species-specific epitopes on the development of a multi-species anti-schistosome vaccine are discussed.  相似文献   
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Streptococcus agalactiae, also designated group B streptococcus (GBS), is an important pathogen in neonates, pregnant women, and nonpregnant adults with predisposing conditions. We used multilocus sequence typing (MLST) to characterize 158 GBS isolates that were associated with neonatal and adult invasive disease and that were collected in northern and western Sweden from 1988 to 1997. Five major genetic lineages (sequence type [ST] 19, ST-17, ST-1, ST-23, and ST-9 complexes) were identified among the isolates, including serotype Ia, Ib, and II to V isolates, indicating a highly clonal population structure among invasive GBS isolates. A number of STs were found to contain isolates of different serotypes, which indicates that capsule switching occurred rather frequently. Two distantly related genetic lineages were identified among isolates of serotype III, namely, clonal complex 19 (CC19), and CC17. CC19 was equally common among isolates from adult and neonatal disease (accounting for 10.3% of GBS isolates from adult disease and 18.7% from neonatal disease), whereas CC17 significantly appeared to be associated with neonatal invasive disease (isolated from 21.9% of neonatal isolates but only 2.6% of adult isolates). The distribution of the mobile elements GBSi1 and IS1548 reveals that they can act as genetic markers for lineages CC17 and CC19, respectively.  相似文献   
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Methylprednisolone increases absorptive capacity of rabbit ileum in vitro   总被引:2,自引:0,他引:2  
The effect of glucocorticoids on intestinal ion transport was studied in ileum in vitro from control and methylprednisolone (MP)-treated (40 mg im for 2 days) rabbits under the following conditions: a) basal rates of Na and Cl transport, b) the response to an individual absorptive stimulus (alanine, glucose, or epinephrine), and c) the response to a combination of the three absorptive stimuli. The results indicate that MP 1) increases basal absorption of Na and Cl and secretion of bicarbonate (as measured by residual ion flux), 2) does not alter the specific transport pathways stimulated by maximal doses of alanine, glucose, or epinephrine, but 3) significantly increases the absorptive capacity of ileum. After addition of combined alanine, glucose, and epinephrine, MP-treated ileum absorbed 15.8 mueq X cm-2 X h-1 Na (vs. 6.6 in controls, P less than 0.001) and 9.5 mueq X cm-2 X h-1 Cl (vs. 4.1 in controls, P less than 0.005). Additionally MP did not alter the Na dependence of either the short-circuit current or Cl absorption found in controls, although there appears to be a portion of residual ion flux insensitive to epinephrine inhibition. These data suggest that the MP-induced increase in absorptive capacity is due to an increase in a postapical transport step, most probably the Na pump.  相似文献   
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The ambulatory electrocardiogram (ECG) is an important medical tool, not only for diagnosis of adverse cardiac events, but also to predict the risk of such events occurring. The 24-hour ambulatory ECG has certain problems and drawbacks because the signal is corrupted by noise from various sources and also several other conditions which may alter the ECG morphology. We have developed a Windows based program for the computer analysis of ambulatory ECG which attempts to address these problems. The software includes options for importing ECG data, different methods of waveform analysis, data-viewing, and exporting the extracted time series. In addition, the modular structure allows for flexible maintenance and expansion of the software. The ECG was recorded using a Holter device and oversampled to enhance the fidelity of the low sampling rate of the ambulatory ECG. The influence of different sampling rates on the interval variability were studied. The noise sensitivity of the implemented algorithm was tested with several types of simulated noise and the precision of the interval measurement was reported with SD values. Our simulations showed that, in most of the cases, defining the end of QT interval at the maximum of the T wave gave the most precise measurement. The definition of the onset of the ventricular repolarization duration is most precisely made on the maximum or descending maximal slope of the R wave. We also analyzed some examples of time series from patients using power spectrum estimates in order to validate the low level QT interval variability.  相似文献   
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Diarrhea is best defined as passage of loose stools often with more frequent bowel movements. For clinical purposes, the Bristol Stool Form Scale works well to distinguish stool form and to identify loose stools. Laboratory testing of stool consistency has lagged behind. Acute diarrhea is likely to be due to infection and to be self‐limited. As diarrhea becomes chronic, it is less likely to be due to infection; duration of 1 month seems to work well as a cut‐off for chronic diarrhea, but detailed scientific knowledge is missing about the utility of this definition. In addition to duration of diarrhea, classifications by presenting scenario, by pathophysiology, and by stool characteristics (e.g. watery, fatty, or inflammatory) may help the canny clinician refine the differential diagnosis of chronic diarrhea. In this regard, a careful history remains the essential part of the evaluation of a patient with diarrhea. Imaging the intestine with endoscopy and radiographic techniques is useful, and biopsy of the small intestine and colon for histological assessment provides key diagnostic information. Endomicroscopy and molecular pathology are only now being explored for the diagnosis of chronic diarrhea. Interest in the microbiome of the gut is increasing; aside from a handful of well‐described infections because of pathogens, little is known about alterations in the microbiome in chronic diarrhea. Serological tests have well‐defined roles in the diagnosis of celiac disease but have less clearly defined application in autoimmune enteropathies and inflammatory bowel disease. Measurement of peptide hormones is of value in the diagnosis and management of endocrine tumors causing diarrhea, but these are so rare that these tests are of little value in screening because there will be many more false‐positives than true‐positive results. Chemical analysis of stools is of use in classifying chronic diarrhea and may limit the differential diagnosis that must be considered, but interpretation of the results is still evolving. Breath tests for assessment of carbohydrate malabsorption, small bowel bacterial overgrowth, and intestinal transit are fraught with technical limitations that decrease sensitivity and specificity. Likewise, tests of bile acid malabsorption have had limited utility beyond empirical trials of bile acid sequestrants.  相似文献   
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