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91.
There is a need recognized by the National Institute of Dental & Craniofacial Research and the National Cancer Institute to advance basic,translational and clinical saliva research. The goal of the Salivaomics Knowledge Base (SKB) is to create a data management system and web resource constructed to support human salivaomics research. To maximize the utility of the SKB for retrieval,integration and analysis of data,we have developed the Saliva Ontology and SDxMart. This article reviews the informatics advances in saliva diagnostics made possible by the Saliva Ontology and SDxMart.  相似文献   
92.
Previous research has shown that basal forebrain cholinergic inputs to the cerebral cortex are necessary for attentional processing. However, the key components of attention-demanding tasks for demonstrating deficits following loss of basal forebrain corticopetal cholinergic neurons are unclear. In the present experiment, rats were trained in a visual cued discrimination task with limited explicit attentional demands and then received intrabasalis infusions of the immunotoxin, 192 IgG-saporin, or saline. Postsurgically, attentional demands were increased by decreasing the signal duration or the intertrial interval or by increasing the variability of these parameters. Subsequently, rats were trained in a task that required discrimination of successively presented signals and "blank" trials with no signal presentation. Again, attentional demands were increased by manipulating signal duration or the intertrial interval. Finally, all rats were trained in a task with both the signal duration and the intertrial interval designed to increase attentional demands. Compared to sham-lesioned animals, lesioned animals exhibited deficits in signal detection only during the successive discrimination task with both the signal duration and intertrial interval shorter and variable. The present data suggest that attentional deficits following loss of cortical cholinergic inputs result from overall attentional task demands rather than being dependent on any single task parameter.  相似文献   
93.
Sarcoidosis.     
PURPOSE OF REVIEW: Research conducted in recent years has added to our current understanding of the epidemiologic, immune, and genetic factors involved in the pathogenesis of sarcoidosis. RECENT FINDINGS: Exposure to an environmental or occupational antigen in a genetically susceptible individual is thought to trigger an immunologic response. The cells and cytokines that lead to granuloma formation have been an area of active study. Certain human leukocyte antigen genes appear to play roles in susceptibility and disease phenotype, and two genome scans have identified candidate genes. A genetic susceptibility has been suggested for ocular involvement as well. High-resolution computed tomography has been invaluable in selected patients, and new radionucleotide techniques are currently being developed. The tumor necrosis factor alpha antagonist infliximab has been used successfully in cases of refractory sarcoidosis, whereas the use of etanercept in the treatment of sarcoidosis has been disappointing, and may actually cause the disease. SUMMARY: Recent advances in our understanding of the immunologic events in sarcoidosis may lead to developments in treatments that would further decrease systemic and ocular morbidity.  相似文献   
94.
Hyperkalaemia is a potentially fatal disorder that demands direct treatment. The efficacy of traditional medical treatment is unpredictable, limited, of short duration or carries the risk of serious adverse events. The administration of salbutamol for hyperkalaemia in children is described in several clinical trials and case reports.

Conclusion: Salbutamol, inhaled or infused, is safe and efficacious and results in a predictable and long-lasting reduction in serum potassium. Salbutamol merits a place as the preferred medication for hyperkalaemia in children without arrhythmias. If follow-up with haemodialysis is required, the administration of salbutamol gives time to make the necessary preparations.  相似文献   
95.
OBJECTIVE: To determine the effect of nocturnal hypoglycaemia on sleep architecture in adolescents with insulin dependent diabetes mellitus (IDDM). DESIGN: 20 adolescents with IDDM (mean age 12.8 years, mean glycated haemoglobin (HbA1c) 8.9%) were studied on one night. Plasma glucose was measured every 30 minutes and cortisol and growth hormone levels every 60 minutes. Sleep was recorded using standard polysomnographic montages, and sleep architecture was analysed for total sleep time, stages 1-4, rapid eye movement, fragmentation, and arousals. RESULTS: Six subjects (30%) became hypoglycaemic (five subjects < 2.5 mmol/l), with one being symptomatic. There were no differences in age, HbA1c, duration of diabetes, or insulin regimen between hypoglycaemic and non-hypoglycaemic subjects. Hypoglycaemia was not predicted by glucose measurements before bed. There was no detectable rise in plasma cortisol or growth hormone concentrations during hypoglycaemia. Sleep architecture was not disturbed by nocturnal hypoglycaemia with no differences found in sleep stages, fragmentation, or arousals. CONCLUSIONS: Nocturnal hypoglycaemia is a common and usually asymptomatic complication of treatment in adolescents with IDDM. Moderate hypoglycaemia has not been shown to affect sleep architecture adversely. These findings are consistent with, and may explain, the observation that severe hypoglycaemia, with consequent seizure activity, is more common at night than during the day. Counterregulatory hormone responses to nocturnal hypoglycaemia may be less marked than with similar degrees of diurnal hypoglycaemia.  相似文献   
96.
97.
PURPOSE: Ocular side effects attributable to intravenous fluorescein dye are not well characterized. The purpose of this report was to describe three patients with an unusual ocular reaction after the intravenous administration of fluorescein dye. METHODS: Retrospective review of the clinical and photographic records of three patients. RESULTS: Each patient had some type of preexisting ocular inflammatory disease. Each patient described the subacute onset of a unilateral burning sensation and tearing several minutes after the administration of intravenous fluorescein dye. Findings included a new onset of or a worsening of unilateral conjunctival chemosis and injection in all three patients and yellowish discoloration of the conjunctiva in two patients. In each patient, the noninflamed (fellow) eye did not develop any symptoms or show any visible reaction. The symptoms and findings resolved promptly in the affected eye without specific treatment or effect on vision. CONCLUSIONS: Ocular side effects of intravenous fluorescein dye can include transient symptomatic burning and tearing associated with conjunctival chemosis, injection, and yellowish discoloration. Eyes with active inflammatory diseases may be predisposed to this rare effect through an unclear mechanism.  相似文献   
98.
1 肝素类药物的基本特性 1.1 肝素的化学性质肝素是天然氨基葡聚糖,由肥大细胞产生。药用的肝素由猪或牛的黏膜中提取。肝素由糖醛酸链和葡糖胺链交替组成, 含多少不等的硫酸根,相对分子质量5 ku~35 ku。现在使用  相似文献   
99.
STATEMENT OF PROBLEM; Several studies have attempted to determine the ideal combination of dental materials and laboratory techniques to produce the most accurate dental cast. Most have made use of 2-dimensional manual measuring devices, which neglect to account for the dimensional changes that exist along a 3-dimensional surface. PURPOSE: The purpose of this study was to determine the effect of impression tray selection and cast formation techniques on the dimensional change of a dental cast with the use of new, 3-dimensional optical digitizing technology. MATERIAL AND METHODS: Multiple impressions of a machined steel die that resembled a dental arch were made with custom and stock impression trays and vinyl polysiloxane impression material. The impressions were poured in type V artificial dental stone and allowed to set with the tray inverted or noninverted. The steel master die and stone casts were digitized with the Steinbichler Comet 100 Optical Digitizer, which was developed at the Minnesota Dental Research Center for Biomaterials and Biomechanics. Three-dimensional images of the stone casts were aligned to the 3-dimensional image of the master die and analyzed with AnSur-NT software. Multiple measurements of the master die and stone casts were analyzed to determine the accuracy of the 3-dimensional technology and of the impression and cast fabrication techniques. Planar distances between the center of each crown preparation were measured, as were crown heights. Data were analyzed with analysis of variance (P<.05), and root mean square error values were determined. RESULTS: Casts were compared with a total of 45 significance tests, of which only 4 yielded P<.05. There was no pattern to these results, which suggests that they were false-positive findings. CONCLUSION: Results obtained with the use of new optical digitizing technology indicated that neither impression tray type nor cast formation technique affected the accuracy of final casts.  相似文献   
100.
OBJECTIVE: To describe an outbreak of infections with permanent cuffed hemodialysis catheters recognized through ongoing surveillance and related to a specific malfunctioning permanent catheter. DESIGN: The outbreak was suspected from the results of prospective infection surveillance and confirmed by a retrospective cohort study using medical records for patients receiving dialysis between April 1, 1999, and March 31, 2000. SETTING: Integrated network of six outpatient hemodialysis facilities in southern Idaho and eastern Oregon. PATIENTS: Outpatients receiving long-term hemodialysis. RESULTS: During the 18 months prior to the outbreak, the overall infection rate was 4.1 infections per 1,000 dialysis sessions with a catheter rate of 8.9 per 1,000 dialysis sessions. During the 7 months of the outbreak, the overall rate increased to 5.8 per 1,000 dialysis sessions, whereas the catheter rate increased to 18.1 per 1,000 dialysis sessions. Reports of malfunctioning "Brand A" catheters prompted discontinuation of their placement. A manufacturer recall occurred in April 2000. During the 14 months after the outbreak, the overall infection rate decreased to 3.3 per 1,000 dialysis sessions and the catheter rate to 10.8 per 1,000 dialysis sessions. A 12-month retrospective cohort study recognized 96 patients with an identifiable catheter brand and 48 infections. Of these, 27 (56%) occurred in patients with Brand A catheters. The relative risk for infection when compared with other catheter brands was 1.96 (95% confidence interval, 1.32 to 2.92; P < .001). CONCLUSIONS: Ongoing infection surveillance in hemodialysis facilities can identify specific device-related outbreaks of infections and promote interventions to reduce infectious complications and promote patient safety. Surveillance for vascular access site infections is recommended as a routine activity in hemodialysis facilities.  相似文献   
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