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71.
Andrews  RG; Singer  JW; Bernstein  ID 《Blood》1986,67(3):842-845
A monoclonal antibody, 12-8, prepared against KG-1a cells, recognizes an approximately 115-kd cell surface antigen and reacts with 3% to 4% of bone marrow cells, including most of the blast cells. The antigen is not expressed on peripheral blood cells. Marrow cells expressing 12-8 collected by fluorescence-activated cell sorting contained nearly all of the unipotent (CFU-GM, BFU-E) and multipotent (CFU-MIX) colony- forming cells. The isolated 12-8 positive marrow population also contained precursors of these colony-forming cells. In a two-stage long- term marrow culture system employing irradiated allogeneic marrow adherent cells, 12-8 positive cells produced both unipotent and multipotent colony-forming cells for ten weeks. Moreover, the output of colony forming cells substantially exceeded the input. Antibody 12-8 appears useful for analysis and possibly enrichment of hematopoietic progenitor cells that include colony-forming cell precursors.  相似文献   
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73.
Background: Limited data support a recommended maximum osmolarity for administration of peripheral parenteral nutrition (PPN). In this retrospective, matched‐cohort study, we evaluated the incidence of phlebitis or infiltration associated with administration of PPN with an osmolarity >1000 mOsm/L vs ≤1000 mOsm/L. Materials and Methods: Patients ≤18 years old who received PPN in a 2‐year period were included in the study. Data related to patient demographics, PPN constituents, and adverse effects were analyzed. Results: A total of 352 patients met entry criteria. Overall, 139 (40%) patients experienced phlebitis or infiltration. There were no differences between patients who did or did not develop adverse events in terms of age or weight. Administration of PPN with osmolarity >1000 mOsm/L vs ≤1000 mOsm/L significantly increased infiltration (17% vs 7%; odds ratio [OR, 2.47]; 95% confidence interval [CI], 1.24–4.94; P = .01) and the combined composite end point of phlebitis or infiltration (45% vs 34%; OR, 1.65; 95% CI, 1.07–2.54; P = .02). In multivariate analysis, osmolarity >1000 mOsm/L vs ≤1000 mOsm/L was an independent risk factor for developing complications (OR, 1.67; 95% CI, 1.08–2.52; P = .02). Conclusion: Two of every 5 children experienced phlebitis or infiltration during administration of PPN. These adverse effects were more often observed in those who received PPN with osmolarity >1000 mOsm/L vs ≤1000 mOsm/L. With this high incidence of adverse effects, we recommend that if PPN is used, the osmolarity should not exceed 1000 mOsm/L. More important, PPN should only be used temporarily until central access is obtained.  相似文献   
74.
Data from the European School Survey Project on Alcohol andother Drugs have shown that adolescent substance use is a growingproblem in western and particularly Eastern European countries.This paper describes the development, implementation and resultsof the Icelandic Model of Adolescent Substance Use Prevention.The Icelandic Model is a theoretically grounded, evidence-basedapproach to community adolescent substance use prevention thathas grown out of collaboration between policy makers, behaviouralscientists, field-based practitioners and community residentsin Iceland. The intervention focuses on reducing known riskfactors for substance use, while strengthening a broad rangeof parental, school and community protective factors. Annualcross-sectional surveys demonstrate the impact of the interventionon substance use among the population of 14- to 16-year-oldIcelandic adolescents. The annual data from two cohorts of over7000 adolescents (>81% response rate) show that the proportionsof those who reported being drunk during the last 30 days, smokingone cigarette or more per day and having tried hashish onceall declined steadily from 1997 to 2007. The proportions ofadolescents who reported spending time with their parents andthat their parents knew with whom they were spending their timeincreased substantially. Other community protective factorsalso showed positive changes. Although these data suggest thatthis adolescent substance use prevention approach successfullystrengthened a broad range of parental, school and communityprotective factors, the evidence of its impact on reducing substanceuse needs to be considered in light of the correlational dataon which these observations are based.  相似文献   
75.
76.

Purpose

It has been proposed that biological/chemical substances in the intestine might play a role in the occurrence and deterioration of perianal fistulas. Elimination of such unidentified factors from the lower gastrointestinal tract might offer a new strategy for the management of anal fistulas. The aim of this study was to evaluate the clinical effects on non-Crohn’s disease perianal fistula healing, and the safety and tolerability of a new medical device that applies high-purity, high-activity granular activated carbon locally into the rectum twice daily of patients with perianal fistulas without any concomitant medication.

Methods

An open, single-arm, prospective study with active treatment for 8 weeks and an optional follow-up until week 24 (ClinicalTrial.gov identifier NCT01462747) among patients with chronic, uncomplicated perianal fistulas scheduled for surgery was conducted.

Results

Of 28 patients included, 10 patients (35.7%) showed complete fistula healing (closed, no discharge on palpation) after 8 weeks; seven of these patients, corresponding to 25% of the enrolled patients, remained in remission for up to 31 weeks. At week 8, there was a statistically significant reduction in the discharge visual analog scale (p = 0.04), a significant improvement in the patient-perceived quality of life for the category of embarrassment (p = 0.002), and a trend toward improvement in the other assessment categories.

Conclusions

The treatment was well tolerated, and patient acceptance was high. The results support the efficacy and safety of locally administered activated carbon for the treatment of patients with chronic uncomplicated perianal fistulas not receiving any other medication for fistula problems.
  相似文献   
77.
Freezing of gait (FOG) in Parkinson’s disease (PD) likely results from dysfunction within a complex neural gait circuitry involving multiple brain regions. Herein, cerebellar activity is increased in patients compared to healthy subjects. This cerebellar involvement has been proposed to be compensatory. We hypothesized that patients with FOG would have a reduced ability to recruit the cerebellum to compensate for dysfunction in other brain areas. In this study cerebellar activity was modified unilaterally by either excitatory or inhibitory theta burst stimulation (TBS), applied during two separate sessions. The ipsilateral cerebellar hemisphere, corresponding to the body side most affected by PD, was stimulated. Seventeen patients with PD showing ‘off’ state FOG participated. The presence of FOG was verified objectively upon inclusion. We monitored gait and bimanual rhythmic upper limb movements before and directly after TBS. Gait was evaluated with a FOG-provoking protocol, including rapid 360° turns and a 10-m walking test with small fast steps. Upper limb movement performance was evaluated with a repetitive finger flexion–extension task. TBS did not affect the amount of freezing during walking or finger tapping. However, TBS did increase gait speed when walking with small steps, and decreased gait speed when walking as fast as possible with a normal step size. The changes in gait speed were not accompanied by changes in corticospinal excitability of M1. Unilateral cerebellar TBS did not improve FOG. However, changes in gait speed were found which suggests a role of the cerebellum in PD.  相似文献   
78.

BACKGROUND AND PURPOSE

Vasoactive intestinal peptide is expressed in the respiratory tract and induces its effects via its receptors, VPAC1 and VPAC2. RO5024118 is a selective VPAC2 receptor agonist derived via chemical modification of an earlier VPAC2 agonist, RO0251553. In the present studies, we characterized the pharmacological activity of RO5024118.

EXPERIMENTAL APPROACH

Stability of RO5024118 to human neutrophil elastase was assessed. Bronchodilatory activity of RO5024118 was investigated in guinea pig and human isolated airway smooth muscle preparations and in a guinea pig bronchoconstriction model. Pulmonary anti-inflammatory activity of RO5024118 was investigated in a lipopolysaccharide mouse model and in a porcine pancreatic elastase (PPE) rat model.

KEY RESULTS

RO5024118 demonstrated increased stability to neutrophil elastase compared with RO0251553. In human and guinea pig isolated airway preparations, RO5024118 induced bronchodilatory effects comparable with RO0251553 and the long-acting β-agonist salmeterol and was significantly more potent than native vasoactive intestinal peptide and the short-acting β-agonist salbutamol. In 5-HT-induced bronchoconstriction in guinea pigs, RO5024118 exhibited inhibitory activity with similar efficacy as, and longer duration than, RO0251553. In a lipopolysaccharide-mouse model, RO5024118 inhibited neutrophil and CD8+ cells and myeloperoxidase levels. In rats, intratracheal instillation of PPE induced airway neutrophilia that was resistant to dexamethasone. Pretreatment with RO5024118 significantly inhibited PPE-induced neutrophil accumulation.

CONCLUSIONS AND IMPLICATIONS

These results demonstrate that RO5024118 induces dual bronchodilatory and pulmonary anti-inflammatory activity and may be beneficial in treating airway obstructive and inflammatory diseases.  相似文献   
79.

Purpose

Until now there are no systematic studies about the long-term course of myoma growth. Therefore, the aims of the present study were: (1) ultrasound monitoring of the natural course of growth of uterine leiomyomas; (2) assessment of whether the growth of myomas depends on the age of the patients, the location, or the initial size (possible co-factors/predictor criteria for increase of growth); influence of oral contraceptives (OC).

Methods

Patient records (2010–May 2016) were retrospectively and systematically evaluated in regards to their growth and clinical course. The patients received a follow-up questionnaire by mail about the further history. Linear regression analysis and generalized regression analysis were performed to determine the influence of various factors on the growth of myomas.

Results

Overall, 152 met the further inclusion criteria. Most of the myomas increased in size but 10% of the myomas became smaller without therapy. There is a significant dependency between the initial myoma size, and the first and second measurements, but not between those measures and myoma localization. In regression analysis, there was also a significant association between the growth of the myomas and the initial size but no association with age, complaint symptoms, and use of OC. However, the use of OC waas significantly associated with myoma growth in GEE.

Conclusions

The course of growth of myomas has large variance, so this should not be taken as a sign for a malignant event (sarcoma or the so-called STUMP). The growth takes place with considerable individual variability and ultimately is not predictable.
  相似文献   
80.
Substance use is associated with impaired social cognition. Experimental studies have shown that acute intoxication of alcohol, tobacco, and cannabis decreases the performance in non-verbal, social communication and theory of mind tasks. However, in epidemiological studies the temporal direction of this association has gone relatively unstudied. We investigated both directions of association within an adolescent birth cohort: the association of social cognition with subsequent substance use, and the association of early substance use with subsequent social cognition. We used data from the Avon Longitudinal Study of Parents and Children, a UK birth cohort. Logistic regression indicated that poor childhood non-verbal communication was associated with decreased odds of adolescent alcohol (OR 0.70, 95% 0.54–0.91), tobacco (OR 0.62, 95% CI 0.47–0.83), and cannabis use (OR 0.62, 95% CI 0.46–0.83). Early adolescent substance use was associated with increased odds of poor social communication (alcohol: OR 1.46, 95% CI 0.99–2.14; tobacco: OR 1.95, 95% CI 1.33–2.86) and poor social reciprocity (alcohol: OR 1.57, 95% CI 1.18–2.09; tobacco: OR 1.92, 95% CI 1.43–2.58; cannabis: OR 1.54, 95% CI 1.16–2.05). Overall, the relationship between social cognition and substance use was different in each temporal direction. Poor non-verbal communication in childhood appeared protective against later substance use, while adolescent substance use was associated with decreased social cognitive performance.  相似文献   
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