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1.
We conducted a prospective randomized double blind study to determine: (1) the safety and immunogenicity of live oral tetravalent human-rhesus rotavirus reassortant vaccine in neonates; and (2) whether a second dose at the age of 6 to 8 weeks enhances the immunogenicity. Two hundred forty healthy neonates were enrolled and received vaccine (183) or placebo (57) on the second day of life. At the age of 6 to 8 weeks 133 received placebo and 88 received a second dose of vaccine. Medical events were noted within 10 days from vaccine administration in 6 of 183 (3.3%) vaccine recipients vs. 0 of 57 placebo recipients (P = 0.34) after the first dose and in 8 of 88 (9%) vs. 4 of 133 (3%) after the second dose (P = 0.069); none was severe and all were of short duration. Seroresponse of any type (detectable IgA or 4-fold increase of titer to rhesus rotavirus was 9% for the placebo, vs. 52 and 46% for those who received one and two doses of vaccine, respectively. However, neutralizing antibodies against human serotypes 1, 2 and 3 were not raised successfully in vaccinated infants when compared with placebo recipients. The same pattern was found when geometric mean titers were compared. Vaccine take was better when cord blood titers were low. At the age of 1 year the vaccinees had more often high titers for antirhesus rotavirus antibodies (> 640) than the placebo recipients (49% vs. 0%; P < 0.001). NO difference was found between the groups in neutralizing antibodies to human serotypes 1, 2 and 3 rotavirus.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Chemotoxicity of indium-111 oxine in mammalian cells   总被引:2,自引:0,他引:2  
We have studied the uptake and toxicity of [111In]oxine in Chinese hamster V79 lung fibroblasts. The incorporation of the radionuclide into these cells reached a plateau within 2 hr. Uptake was proportional to the extracellular radioactive concentration. Both radioactive and "decayed" [111In]oxine exhibited similar toxicities, indicating that the observed toxicity was chemical in nature. These results are discussed in terms of the present status of this radiolabeling agent.  相似文献   
3.
Noninvasive monitoring of gene transfer will benefit basic research and patient care. Most gene-transfer imaging systems do not directly detect the gene of interest, and most do not exploit radiopharmaceuticals that have Food and Drug Administration approval for total-body use. (111)In-Octreotide is used clinically to locate tumors overexpressing primarily somatostatin receptor type 2 (SSTR2). We report the in vitro and in vivo detection of SSTR2 chimeric gene transfer with this radiopharmaceutical. METHODS: Full-length SSTR2A was ligated into a vector downstream of a 5' Igkappa leader sequence and the hemagglutinin A (HA) sequence. The vector plus insert was then introduced into HT1080 cells. Igkappa and HA domain functions were confirmed by immunologic methods. Receptor binding was studied in transfected cells incubated with (111)In-octreotide with and without somatostatin-28. Mice bearing tumors produced by transfected cells were injected with (111)In-octreotide for biodistribution and imaging studies. RESULTS: Cell-membrane localization by the amino-terminal Igkappa domain was confirmed by immunofluorescence. The HA domain was identified by enzyme-linked immunosorbent assay, immunofluorescence, and Western blotting analysis with anti-HA antibodies. (111)In-Octreotide detected the SSTR2 portion of the fusion protein in vitro (receptor-binding assay) and in vivo (biodistribution studies and gamma-camera imaging). In addition, in vitro studies using either the anti-HA antibody or (111)In-octreotide correlated with biodistribution and imaging studies when cell clones expressing different levels of the fusion protein were tested. This approach may be feasible clinically because we were able to discern chimeric gene transfer in tumor-bearing animals with (111)In-octreotide at doses similar to those already used in humans. CONCLUSION: With this method it may be possible to monitor transfer of a gene of interest directly and noninvasively.  相似文献   
4.
Factors predicting ventilator-associated pneumonia recurrence   总被引:2,自引:0,他引:2  
OBJECTIVE: To determine the factors associated with ventilator-associated pneumonia recurrence in patients alive after 8 days of treatment for a first episode. DESIGN: A 16-month, prospective, observational cohort study of patients diagnosed with a first ventilator-associated pneumonia episode. Predictors of recurrence were assessed by logistic regression analysis. SETTING: Two intensive care units in a university hospital. PATIENTS: Bronchoscopy was performed in 124 patients with clinically or radiologically suspected ventilator-associated pneumonia. Ventilator-associated pneumonia was confirmed by the presence of at least two of the following criteria: >/=2% of cells with intracellular bacteria found on direct examination of bronchoalveolar lavage fluid, protected specimen brush sample culture >/=103 colony-forming units/mL, or bronchoalveolar lavage culture >/=104 colony-forming units/mL. Ventilator-associated pneumonia recurrence was confirmed using the same microbiological criteria. Antibiotic treatment for ventilator-associated pneumonia lasted 14 days. MEASUREMENTS AND MAIN RESULTS: Clinical, radiologic, and biological data at intensive care unit admission, on the day of bronchoscopy (D1) and on D8, and outcome variables were prospectively recorded. Ventilator-associated pneumonia recurred in 28 patients (all of them still on mechanical ventilation on D8), 21 +/- 9 days after the first episode (82% after D14). Factors significantly associated with recurrence were: acute respiratory failure as initial reason for mechanical ventilation, D1 radiologic score >7, D8 radiologic score >8, adult respiratory distress syndrome on D8, mechanical ventilation persistence on D8, D8 temperature >38 degrees C, and D8 temperature >D1 temperature, but not disease-severity scores at inclusion and D8, or first-episode pathogen(s). Multivariate analysis identified D1 radiologic score >7 (odds ratio = 3.9; 95% confidence interval, 1.3-11.6), D8 temperature >38 degrees C (odds ratio = 4.4; 95% confidence interval, 1.4-13.4), and adult respiratory distress syndrome on D8 (odds ratio = 14.6; 95% confidence interval, 1.5-143.5) as predictors of recurrence. CONCLUSIONS: Factors of ventilator-associated pneumonia recurrence evaluated on D8 of a 14-day course of antibiotics are linked to the severity of lung injury and persistence of fever, but not to first-episode pathogen(s).  相似文献   
5.
Acute bronchiolitis (AB) is caused primarily by respiratory syncytial virus (RSV). Recent laboratory tools have implicated a variety of other pathogens; however, their clinical relevance has not been clearly defined. The purpose of this study was to determine whether the etiological agents of AB affect its course. A multicenter prospective study was performed in previously healthy children <24?months of age who presented with <4?days duration of AB. Subjects were divided into the following groups: “only RSV,” “also RSV,” “no RSV,” and “no pathogen.” The clinical severity score on admission as well as the overall severity of disease was assessed. RSV was the most common cause of AB (77.5?%). “Only RSV” or “also RSV” patients had a higher clinical score on admission compared to those with “no RSV,” p?<?0.001 and p?<?0.02, respectively. “Only RSV” and “also RSV” patients had a higher disease severity score when compared to patients with “no RSV,” 5.9?±?1.4 vs. 5.1?±?1.5, p?<?0.001, and 5.6?±?1.4 vs. 5.1?±?1.5, p?<?0.02, respectively. Disease severity did not vary as a function of transfer to the pediatric intensive care unit (PICU) or duration of supplemental oxygen, yet, “only RSV” was associated with a longer length of stay (LOS) than “no RSV,” p?<?0.02. “Only RSV”-related AB was associated with a more severe initial clinical presentation and a longer LOS. There appears to be little immediate clinical benefit to diagnosing RSV AB to the individual patient, but the application of these diagnostic methods may have significant cost-saving implications and, thus, deserves consideration by medical professionals and health policy analysts.  相似文献   
6.
A vascular selective calcium antagonist, felodipine, was evaluated in a randomised, double blind, crossover trial in 18 patients with chronic congestive heart failure of ischaemic cause. Felodipine (10 mg twice daily) or a corresponding placebo was added to conventional treatment. After three weeks haemodynamic function was assessed at rest, during a standard supine leg exercise, and during 45 degrees passive upright tilt. In patients in the supine resting position, felodipine reduced the mean arterial pressure (9%) and systemic vascular resistance (24%) and increased the stroke volume (25%) and cardiac index (23%). The heart rate and right and left ventricular filling pressures were unchanged. During felodipine treatment the standard exercise was accomplished at a similar cardiac index but at a substantially lower heart rate (7%), arterial pressure (10%), systemic vascular resistance (17%), and left ventricular filling pressure (19%), and a higher stroke volume (13%). During both placebo and felodipine administration there were substantial reductions in cardiac filling pressure during upright tilting. Upright tilting during the placebo phase did not increase the heart rate. It also caused a greater fall in systemic vascular resistance while the arterial pulse pressure but not the mean pressure was maintained and the cardiac index and stroke volume increased. The reduced cardiac filling pressures during the felodipine upright tilt were accompanied by reductions in arterial pulse pressure and stroke volume and the patients were able to maintain the mean arterial pressure by an increase in both the heart rate and systemic vascular resistance. Thus three weeks treatment with felodipine improved haemodynamic function at rest and during standard exercise and normalised the baroreflex mediated haemodynamic response in patients with congestive heart failure. The haemodynamic efficacy of the drug in such patients may be associated with a baroreceptor mediated effect as well as direct vasodilatation.  相似文献   
7.
8.
Mechanisms controlling forearm muscle vascular resistance (FMVR) during postural changes were investigated in seven patients with severe congestive heart failure (CHF) and in seven control subjects with unimpaired left ventricular function. Relative brachioradial muscle blood flow was determined by the local 133Xe-washout technique. Unloading of baroreceptors with use of 45 degree upright tilt was comparably obtained in the patients with CHF and control subjects. Control subjects had substantially increased FMVR and heart rate to maintain arterial pressure whereas patients with CHF had decreased FMVR by 51 +/- 11% (mean +/- SEM, p less than .02) and had no increase in heart rate despite a fall in arterial pressure during upright tilt. The autoregulatory and local vasoconstrictor reflex responsiveness during postural changes in forearm vascular pressures were intact in both groups. Further investigations were carried out in the patients with CHF. The left axillary nerve plexus was blocked by local anesthesia in the seven patients. No alterations in forearm vascular pressures were observed. This blockade preserved the local regulation of FMVR but reversed the vasodilator response to upright tilt as FMVR increased by 30 +/- 7% (p less than .02). Blockade of central neural impulses to this limb combined with brachial arterial infusions of phentolamine completely abolished the humoral vasoconstriction in the tilted position. Infusions of propranolol to the contralateral brachial artery that did not affect baseline values of heart rate, arterial pressure, or the local reflex regulation of FMVR reversed the abnormal vasodilator response to upright tilt as FMVR increased by 42 +/- 12% (p less than .02). Despite augmented baseline values, forearm venous but not arterial plasma levels of epinephrine increased in the tilted position, as did arterial rather than venous plasma concentrations of norepinephrine in these patients. The results suggest a beta-adrenergic reflex mechanism elicited by spinal or supraspinal neural impulses and probably modulating a cotransmitter release in the patients with CHF.  相似文献   
9.
European Journal of Clinical Microbiology & Infectious Diseases - The purpose of this study was to estimate the impact of pneumococcal conjugate vaccine-13 (PCV-13) introduction into the...  相似文献   
10.
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