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91.
OBJECTIVES: We aimed to evaluate the performance of a newly designed temporary stent device as a percutaneous emergency treatment of pulmonary embolism. BACKGROUND: If thrombolysis is contraindicated or recanalization by thrombolysis delayed in patients with severe pulmonary embolism who are threatened by acute circulatory failure, percutaneous temporary pulmonary stent placement may represent an additional option before surgical embolectomy is considered. METHODS: The newly designed temporary pulmonary stent is made from woven Nitinol and has a distal blunt end and a proximal crimped end, which is firmly fixed to a 0.035-inch guidewire. It is delivered through a 9.5-F polytetrafluoroethylene sheath using a pusher tube. Stent placement and removal were examined in 9 anesthetized sheep with experimentally induced pulmonary embolism. Hemodynamic parameters were recorded in 7 animals. RESULTS: Delivery and removal of the stent was uneventful and rapidly accomplished. Stent placement was associated with a significant decrease in Miller angiographic index (from 11.2 +/- 3.1 to 3.8 +/- 1.9; p = 0.0001), heart rate (from 139 +/- 35 beats/min to 92 +/- 11 beats/min; p = 0.0129), and mean pulmonary artery pressure (from 32 +/- 14 mm Hg to 21 +/- 14 mm Hg; p = 0.0029) and a significant increase in mean aortic pressure (from 48 +/- 14 mm Hg to 61 +/- 8 mm Hg; p = 0.0080). Autopsy revealed neither wall damage nor parenchymal hemorrhage. CONCLUSIONS: Our preliminary study proves the technical feasibility of temporary placement and removal of a newly designed dedicated pulmonary stent to recanalize centrally located embolic occlusions in severe pulmonary embolism. Animal experimental evaluation revealed rapid and significant circulatory improvement after stent placement.  相似文献   
92.
OBJECTIVES: Our study goal was to analyze whether gene variants of angiotensin II type 2-receptor (AT2-R) modulate the effects of angiotensin II on the left ventricle (LV). BACKGROUND: Experimental data suggest that angiotensin II modifies ventricular growth responses via angiotensin II type 1-receptors (AT1-R) and AT2-R. METHODS: In 120 white, young male subjects with normal or mildly elevated blood pressure, we assessed plasma angiotensin II and aldosterone concentrations (RIA), 24-h urinary sodium excretion, 24-h ambulatory blood pressure and LV structure (two-dimensional guided M-mode echocardiography). The intronic +1675 G/A polymorphism of the X-chromosomal located AT2-R gene was investigated by single-strand conformational polymorphism analysis and DNA-sequencing. RESULTS: Hypertensive subjects with the A-allele had a greater LV posterior (11.0 +/- 1.3 vs. 9.9 +/- 1.3 mm, p < 0.001), septal (11.8 +/- 1.4 vs. 10.1 +/- 1.2 mm, p < 0.001) and relative wall thickness (0.44 +/- 0.06 vs. 0.39 +/- 0.06, p < 0.01) as well as LV mass index (138 +/- 23 vs. 120 +/- 13 g/m2, p < 0.001) than those with the G-allele. Confounding factors (i.e., body mass index and surface area, plasma angiotensin II, sodium excretion, systolic and diastolic ambulatory blood pressure) were similar between the two genotypes. In normotensive subjects, relative wall thickness (0.36 +/- 0.05 vs. 0.35 +/- 0.05) and LV mass index (115 +/- 21 vs. 112 +/- 17 g/m2) were nearly identical across the two genotypes, with similar confounding variables. CONCLUSIONS: Our data indicate that the X-chromosomal located +1675 G/A-polymorphism of the AT2-R gene is associated with LV structure in young male humans with early structural changes of the heart due to arterial hypertension.  相似文献   
93.
Smoking is the main causative factor for development of head and neck and lung cancer. In addition, other malignancies such as bladder, stomach, colorectal, kidney and pancreatic cancer have a causative relation with smoking. Continued smoking after having been diagnosed with cancer has many negative consequences: effectiveness of radiotherapy is diminished, survival time is shortened and risks of recurrence, second primary malignancies and treatment complications are increased. In view of the significant health consequences of continued smoking, therefore, additional support for patients to stop smoking seems a logical extension of the present treatment protocols for smoking-related cancers. For prospectively examining the effect of nursing-delivered smoking cessation programme for patients with head and neck or lung cancer, 145 patients with head and neck or lung cancer enrolled into this programme over a 2-year period. Information on smoking behaviour, using a structured, programme specific questionnaire, was collected at baseline, and after 6 and 12 months. At 6 months, 58 patients (40%) had stopped smoking and at 12 months, 48 patients (33%) still had refrained from smoking. There were no differences in smoking cessation results between patients with head and neck and lung cancer. The only significant factor predicting success was whether the patient had made earlier attempts to quit smoking. A nurse-managed smoking cessation programme for patients with head and neck or lung cancer shows favourable long-term success rates. It seems logical, therefore, to integrate such a programme in treatment protocols for smoking-related cancers.  相似文献   
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96.
Objectives/Hypothesis: To assess voice characteristics of patients following radiotherapy for early glottic cancer through a multidimensional analysis protocol including vocal function and voice quality measures. Methods: Voice analyses were performed for 60 patients treated with radiotherapy (66 Gy/33 fractions, 60 Gy/30 fractions, or 60 Gy/25 fractions) for early T1 glottic cancer and 20 matched control speakers. There was a longitudinal group of 10 patients for whom data were collected before as well as 6 months and 2 years after radiation. Furthermore, data were collected for five separate groups of 10 patients each, before, 6 months after, 2 years after, 3 to 7 years after, and 7 to 10 years after radiation. Vocal function was investigated by means of videolaryngostroboscopy, phonetography, maximum phonation time, and phonation quotient measures. Voice quality was assessed by means of objective acoustical analysis and subjective perceptual ratings by trained raters. Results: Voice characteristics of patients were decreased before radiotherapy, improved after treatment, and became comparable to the voice characteristics of control speakers in at least 55% of the patients. Following radiotherapy, deviant voice quality was mainly negatively affected by increased age and stripping the vocal cord for initial diagnosis. Stroboscopy revealed that next to increasing age and stripping the vocal cord, continued smoking after treatment decreased vocal function following radio-therapy. Conclusion: Voices of patients diagnosed with early glottic cancer improved but did not normalize fully after radiotherapy. Stripping the vocal cord for initial diagnosis and continued smoking after treatment decreased voice characteristics. A multidimensional analysis protocol including perceptual and acoustical analysis of voice quality and stroboscopic analysis of vocal function is recommended to investigate voice characteristics following treatment for early glottic cancer.  相似文献   
97.

Background.

We report the results of a multicenter randomized phase III study, assessing quality of life (QOL) in intra‐arterial (IA) versus standard intravenous (IV) chemoradiation in advanced head and neck cancer.

Methods.

Two hundred seven patients with inoperable stage IV disease—152 men and 55 women; mean age, 55 years—were included in this study. The patients were treated with standard radiotherapy with 4 weekly IA or 3 weekly IV cisplatin infusions. The QOL assessments carried out were EORTC‐C30, H&N35, and trial‐specific questionnaires.

Results.

Overall QOL deteriorated in all patients during treatment, is gradually improving over 1 year. IA patients showed significantly less nausea and vomiting at week 7 (p <.001). IV patients were significantly more fatigued (p <.006). At 1 year, no significant difference in tube feeding was found. Voice quality slightly exceeded the pretreatment values at 1 year. Forty‐two of 62 employed patients returned to work.

Conclusion.

During treatment, significantly fewer problems with nausea and vomiting occurred in IA than in IV patients. Both groups showed improved voicing and oral intake during follow‐up, often exceeding pretreatment values at 1 year. © 2008 Wiley Periodicals, Inc. Head Neck, 2009  相似文献   
98.
In an in vitro study using Staphylococcus epidermidis RP 62 A, a slime-producing strain and its isogenic slime-negative mutant M7, we demonstrated that both strains adhere to pure titanium discs with significantly higher colony counts for the slime-producing strain. The colony count was dependent on temperature, time and strain. Prolonged incubation time (24 h) under growth conditions leads to higher colony counts for the slime-producing strain RP 62 A. As the slime-negative mutant M 7 can adhere to, but not form multiple layers on metallic surfaces, increase of incubation time does not produce higher colony counts on the metallic surface. We conclude that slime production is important for adherence and subsequent accumulation of S. epidermidis onto pure titanium discs in vitro.  相似文献   
99.
Effect of Pentoxifylline and Tocopherol on Radiation Proctitis/Enteritis   总被引:1,自引:0,他引:1  
BACKGROUND AND PURPOSE: Chronic radiation proctitis/enteritis is a relevant complication of pelvic irradiation, which is still mainly treated by supportive measures only. There is some evidence that the combined treatment with pentoxifylline and tocopherol might alter the pathogenesis of radiation-induced fibrosis. In a retrospective analysis the clinical benefit of the treatment with pentoxifylline/tocopherol on radiation-induced proctitis/enteritis was evaluated, compared to supportive care only. PATIENTS AND METHODS: Of 30 patients with radiation-induced proctitis/enteritis grade I-II according to the RTOG/EORTC toxicity criteria, 21 were treated with pentoxifylline and tocopherol. Depending on physician's decision nine patients received symptomatic treatment only. RESULTS: With pentoxifylline/tocopherol treatment 15/21 patients (71%) experienced a relief of their symptoms. A reduction from grade I/II to grade 0 toxicity was observed in seven and from grade II to grade I toxicity in eight patients. No improvement was seen in six patients. The median time to improvement with pentoxifylline and tocopherol treatment was 28 weeks. In three of nine patients who were treated supportively only, deterioration of symptoms occurred. Three patients experienced no amelioration, and three patients with grade I toxicity experienced a spontaneous relief of their symptoms (33%). CONCLUSION: The combination treatment with pentoxifylline and tocopherol seems to have a benefit in patients with grade I-II radiation-induced proctitis/enteritis. The optimal schedule of treatment duration is not yet clear. From the observations made in this study it is assumed the treatment should be given for 6-12 months at least. A prospective phase II study should be undertaken to evaluate optimal treatment duration.  相似文献   
100.
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