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41.
Fifty healthy children were included in the study; tracheal and laryngeal aspirations were performed after oral endotracheal intubation during minor surgery. The aspirates were evaluated and examined in the same way as aspirates from children suspected of pneumonia; 31 samples were accepted for the final analysis. After culturing, specimens from 30 children exhibited growth of potential pathogenic bacteria either from the larynx, the trachea or both. Prior to culture, bacteria were seen by microscopy in 24 samples from 30 children. These results indicate that the majority of healthy children carry potential pathogenic bacteria, not only in the larynx but also to a certain extent in the trachea. We conclude that aspirates from the larynx and the trachea are of limited value in the diagnosis of bacterial pneumonia in children.  相似文献   
42.
Two xanthones, 2-hydroxyethoxy-6-(5-tetrazoyl) (BW A440C) and 2-ethoxy- 6-(5-tetraozyl) (BW A827C), are members of a chemical series tested in vitro as potential additives to citrate-phosphate-dextrose-adenine (CPDA-1) medium for blood storage. P50 was maintained in the presence of these compounds during 42 days' storage by a partial maintenance of 2,3 diphosphoglycerate (2,3 DPG) and by a direct effect on hemoglobin previously reported for BW A827C. Red cell 2,3 DPG levels for BW A440C (n = 5), BW A827C (n = 5), and control (n = 6), respectively, were 3.38 +/− 0.47, 3.44 +/− 0.25, and 1.20 +/− 0.10 mM +/− SEM on day 7; 1.16 +/− 0.13, 1.52 +/− 0.37, and 0.16 +/− 0.02 mM on day 21; and 0.67 +/− 0.09, 0.61 +/− 0.08, and 0.06 +/− 0.006 mM on day 42. Red cell adenine triphosphate levels at the same time intervals were 1.84 +/− 0.09, 1.46 +/− 0.18, and 2.11 +/− 0.04 mM; 2.10 +/− 0.05, 2.07 +/− 0.17, and 2.13 +/− 0.05 mM; and 1.42 +/− 0.13, 1.37 +/− 0.13, and 1.38 +/− 0.06 mM, respectively. The degree of hemolysis was less with the addition of the compounds, and the methemoglobin formation, plasma Na+ and K+, and lactate production were unaffected by the compounds.  相似文献   
43.
It is unknown why some infants wheeze during upper respiratory tract infections. One possibility is that secretory IgA, which has a major role in mucosal defence against viral infection, might be deficient in wheezy infants. The nasal IgA response to upper respiratory tract infection in 32 wheezy infants (median age 5.8 months) was compared with nine siblings (median age 2.6 years) who had nasal symptoms only. Nasal lavage was performed during infections and on follow up when free from symptoms, using inulin as a marker of dilution to determine absolute concentrations of IgA in the nasal secretions. The two groups showed a similar increase in total IgA and total protein levels during infection, but secretory IgA concentrations were unchanged. This study shows that wheezy infants have a normal nasal IgA response to infection and that the increase in total IgA during early infection is due to plasma exudation rather than increased production of secretory IgA.  相似文献   
44.
Pneumoperitoneum is usually associated with gastrointestinal perforation or following surgical and endoscopic procedures. We report a rare case of spontaneously perforated pyometra presenting with generalised peritonitis and pneumoperitoneum. Perforation of the uterus is also unusual and often associated with the presence of an intrauterine device, a gravid uterus or malignancy. Our case illustrates the importance of clinical knowledge of acute and neoplastic gynaecological diseases, which are not uncommonly encountered by the general surgeon. Moreover, good appreciation of pelvic anatomy and close collaboration with gynaecology colleagues is essential as operative intervention is often required.  相似文献   
45.
46.
SUMMARY The antianginal efficacy of a fixed combination of atenolol (50 mg) and nifedipine (20 mg) was compared with nifedipine (20 mg) alone; 102 patients experiencing three or more anginal attacks on their current monotherapy received each treatment twice daily for 3 weeks in a randomised, double-blind crossover trial. Both treatments reduced the weekly number of angina attacks compared with existing therapy; treatment with the fixed combination resulted in significantly fewer angina attacks per week than treatment with nifedipine alone. Also, when the fixed combination treatment followed the period of nifedipine therapy a further decrease in weekly angina attack rate was apparent. Comparison of individual patient response to each treatment showed that twice as many patients reported lower attack rates while on the fixed combination: 6 patients were withdrawn while receiving fixed combination compared with 10 patients on nifedipine alone. However, the incidence of commonly reported complaints was similar with both treatments.  相似文献   
47.
Hematogones: a multiparameter analysis of bone marrow precursor cells   总被引:1,自引:1,他引:1  
Morphologically distinct lymphoid cells with homogeneous, condensed chromatin and scant cytoplasm can be observed in large numbers in the bone marrow of children with a variety of hematologic and nonhematologic disorders. In some patients, these cells may account for greater than 50% of the bone marrow cells, creating a picture that can be confused with acute lymphoblastic leukemia (ALL) or metastatic tumor. Although originally called hematogones (HGs), a variety of other names have been proposed for these unique cells. The clinical significance of expanded HGs has not been resolved, and the biologic features of these cells are incompletely described. In this study, we correlate the clinical, morphologic, cytochemical, flow cytometric, molecular, and cytogenetic properties of bone marrow samples from 12 children with substantial numbers of HGs (range 8% to 55% of bone marrow cells). Diagnoses in these patients included anemia, four; neutropenia, one; anemia and neutropenia, one; idiopathic thrombocytopenic purpura, two; retinoblastoma, two; Ewing's sarcoma, one; and germ cell tumor, one. Flow cytometric analyses of bone marrow cells demonstrated a spectrum extending from early B-cell precursors (CD10+, CD19+, TdT+, HLA-Dr+) to mature surface immunoglobulin-bearing B cells in these patients, corroborating our morphologic impression of HGs, intermediate forms, and mature lymphocytes. DNA content was normal, and no clonal abnormality was identified by either cytogenetic or immunoglobulin and T-cell receptor (TCR) gene rearrangement studies. Follow-up ranged from 3 months to 3 years. None of the patients has developed acute leukemia or bone marrow involvement by solid tumor. The possible role of HGs in immune recovery and hematopoiesis is presented.  相似文献   
48.

OBJECTIVE:

To describe services received by preschool children diagnosed with autism spectrum disorder (ASD) during the five-year period following their diagnosis.

METHOD:

An inception cohort of preschoolers diagnosed with ASD from Halifax (Nova Scotia), Montreal (Quebec), Hamilton (Ontario), Edmonton (Alberta) and Vancouver (British Columbia) were invited to participate. Parents/caregivers (n=414) described the services provided to their children at four time points: baseline (T1; within four months of diagnosis; mean age three years); six months later (T2); 12 months later (T3); and at school entry (T4). Data were first coded into 11 service types and subsequently combined into four broader categories (no services, behavioural, developmental and general) for analysis.

RESULTS:

More than 80% of children at T1, and almost 95% at T4 received some type of service, with a significant number receiving >1 type of service at each assessment point. At T1, the most common service was developmental (eg, speech-language therapy). Subsequently, the most common services were a combination of behavioural and developmental (eg, intensive therapy based on applied behaviour analysis and speech-language therapy). Service provision varied across provinces and over time.

DISCUSSION:

Although most preschool children with ASD residing in urban centres were able to access specialized services shortly after diagnosis, marked variation in services across provinces remains a concern.  相似文献   
49.
Theodorsson  B; Hedner  U; Nilsson  IM; Kisiel  W 《Blood》1983,61(5):973-981
A method for specific removal of large amounts of factor IX:C alloantibodies by a resin to which highly purified factor IX was linked (factor IX CH-Sepharose) is described. Factor IX was isolated from human plasma by a three-step procedure, including barium citrate adsorption and elution, DEAE-Sepharose CL-6B chromatography, and dextran sulfate agarose chromatography. Approximately 100 mg factor IX was obtained from 60 liters of plasma. The preparation was about 95% pure as judged by SDS-PAA gel electrophoresis. Its specific coagulant activity was 160 U/mg (IX) and its factor IX clotting antigen (IX:Ag) 500-600 U/mg. Essentially quantitative coupling of the factor IX preparation to activated CH-Sepharose 4B was obtained (4 mg factor IX/ml gel; 2300-3000 U/IX:Ag/ml). This resin bound 1500-2000 U factor IX inhibitor/ml gel and could be re-used at least 5 times without any loss in binding capacity. The binding capacity was dependent on the flow rate. No signs of activation of the coagulation, fibrinolytic, or complement system were observed in vitro. Using this factor IX resin, factor IX alloantibodies were isolated and found to consist of two portions, one minor bound to the resin only in the presence of Ca2+ and another major portion Ca2+ independent. The specific inhibitory activity/milligram IgG of the Ca2+-dependent alloantibodies was about 5 times higher in the presence of Ca2+. It is concluded that 25 ml of the factor IX resin described can remove about 40,000 factor IX inhibitor units (comparable to 120,000 Bethesda U) in one run, provided the flow rate does not exceed 20 ml/hr. By using such a technique for removal of antibodies it seems feasible to convert hemophilia-B patients complicated with inhibitors against factor IX into ordinary hemophilia- B patients for treatment at an emergency or in association with major surgery.  相似文献   
50.
Summary. Patients with moderate and severe haemophilia are evaluated on a regular basis at their haemophilia centres but patients with mild haemophilia are seen less often because of fewer problems related to their disease. The needs of patients with milder forms of haemophilia, however, are often underestimated, both by the patient and staff at healthcare facilities. This study evaluated the knowledge of disease and adherence to treatment among patients with severe, moderate and mild haemophilia. This was a prospective multicentre study performed in Haemophilia Centres in Scandinavia. A total of 413 (67%) of 612 patients aged >25 years with mild, moderate and severe haemophilia completed a self‐administered questionnaire. The mean age of the respondents was 49.7 years (range 25–87 years). Of the 413 respondents, 150 had a mild, 86 had a moderate and 177 had a severe form of haemophilia. A total of 22 (5%) patients did not know the severity of their disease, and 230 (56%) patients knew the effect of factor concentrate in the blood. Of the 413 respondents, 53 (13%) of the cohort never treated a haemorrhage. Patients with mild haemophilia, P ≤ 0.001, were the least likely to treat a haemorrhage. The relative number of patients who were afraid of virus transmission by factor concentrate was about similar in the three groups, 27% of those with severe haemophilia, 26% with moderate and 24% with mild haemophilia. This study shows that the amount of knowledge among haemophilia patients about their disease and treatment is somewhat limited, and demonstrates the importance of continually providing information about haemophilia and treatment, especially to patients with a mild form of the disease.  相似文献   
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