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91.
Eosinophilic esophagitis (EoE) is a chronic immune-mediated disease of the esophagus characterized by symptoms related to esophageal dysfunction, as well as significant esophageal eosinophilia.The entity exists worldwide but has been most extensively studied in Western countries. However, a wide range of symptoms has been noticed such as chest pain or gastro-esophageal reflux disease-like symptoms. Upper gastro-intestinal endoscopy and esophageal biopsies are crucial for the diagnosis. Endoscopy might be normal or reveal typical patterns such as rings, furrows, exudates, edema, and stricture. Two to four biopsies should be performed both in the distal and in the proximal esophagus, and 15 eosinophils per high power field within the esophageal epithelium are the minimal threshold to diagnose eosinophilic esophagitis.Allergy testing is recommended, although its impact to orient treatment remains to be demonstrated. Eosinophilic esophagitis treatment includes medical treatment, diet and endoscopic dilation. Proton pump inhibitors are the first-line therapy as up to 50% of patients respond well to proton pump inhibitors irrespective of objective evidence of GERD. Topical viscous corticosteroids or elimination diet are the treatment of choice in case of unresponsiveness to proton pump inhibitors.  相似文献   
92.
We wanted to evaluate the influence of bone cement on the proton range and to derive a conversion factor predicting the range shift by correcting distorted computed tomography (CT) data as a reference to determine whether the correction is needed. Two CT datasets were obtained with and without a bone cement disk placed in a water phantom. Treatment planning was performed on a set of uncorrected CT images with the bone cement disk, and the verification plan was applied to the same set of CT images with an effective CT number for the bone cement disk. The effective CT number was determined by measuring the actual proton range with the bone cement disk. The effects of CT number, thicknesses, and position of bone cement on the proton range were evaluated in the treatment planning system (TPS) to draw a conversion factor predicting the range shift by correcting the CT number of bone cement. The effective CT number of bone cement was 260 Hounsfield units (HU). The calculated proton range for native CT data was significantly shorter than the measured proton range. However, the calculated range for the corrected CT data with the effective CT number coincided exactly with the measured range. The conversion factor was 209.6 [HU · cm/mm] for bone cement and predicted the range shift by approximately correcting the CT number. We found that the heterogeneity of bone cement could cause incorrect proton ranges in treatment plans using CT images. With an effective CT number of bone cement derived from the proton range and relative stopping power, a more actual proton range could be calculated in the TPS. The conversion factor could predict the necessity for CT data correction with sufficient accuracy.  相似文献   
93.
目的:评估埃索美拉唑40mg静脉注射治疗急性非静脉曲张性上消化道出血的疗效和安全。方法:对内镜证实的25例急性非静脉曲张性上消化道出血征象的患者,随机、双盲分为埃索关拉唑组(n=19)和奥美拉唑组(n=6),实验组和对照组分别给予埃索美拉唑和奥美拉唑40mg q12h静脉滴注,治疗5d。观察72h及120h的临床止血疗效及药物不良事件。结果:治疗72h两组临床上无消化道出血征象受试者百分率无显著性差异(P〉0.05)。治疗120h有效率两组均为100%。中位止血时间埃索关拉唑组为41h,奥美拉唑组为20h,两组比较无显著性差异(P〉0.05)。不良事件发生情况两组相似,均无与药物有关的严重不良事件发生。结论:静脉给予埃索美拉唑治疗急性非静脉曲张性上消化道出血疗效不劣于奥美拉唑,和奥美拉唑相比也有很好的耐受性。  相似文献   
94.
马隽 《中国民康医学》2008,20(18):2205-2207
目的:探讨氢质子磁共振波谱分析(^1H—MRS)在碘异常引起海马损害病变中的应用价值。方法:收集临床诊断碘异常引起海马损害的病例38例,其中,低碘组21例,高碘组17例。使用西门子1.5TMRI,多体素相位矩阵扫描。检测低碘组和高碘组患者海马区与常参照区域的代谢物浓度,利用SPSS12.0分析各种代谢物的变化。结果:^1H—MRS示低碘组胆碱降低、γ-氨基丁酸、N-乙酰天门冬氨酸l少;高碘组胆碱增加、谷氨酸升高,γ-氨基丁酸、N-乙酰天门冬氨酸减少。结论:^1H—MRS在碘异常引起海马损害病变定性诊断中有重要自临床价值。  相似文献   
95.
Fifteen patients with esophageal carcinoma (superficial, sixcases; advanced, nine cases) were treated with 250 MeV protonbeam irradiation with or without external x-ray irradiation(12 MV linear accelerator) from October, 1985, to May, 1991.Eleven patients were initially treated with x-ray at doses of16.2-50.4 (mean 42.5) Gy, followed by proton beam at doses of30.0-52.9 (mean 37.6) Gy. The other four patients were treatedwith proton beam alone at total doses of 75.0-88.5 (mean 81.4)Gy. The mean total dose for the 15 patients was 80.4 Gy. Asa result, the primary tumor lesions of all 15 patients disappearedand complete responses were obtained. Approximately four tofive months later, nine of the 15 patients developed esophagealulcer formations at the circumferences of their primary lesions.The ulcerations were healed, however, by conservative management.There was no evidence of local recurrence throughout the observationson six cases of superficial carcinoma. Among nine advanced carcinomapatients, three relapsed into esophageal carcinoma. Recurrenceswere observed eight, 16 and 44 months, respectively, after thetreatment. Ten of the 15 patients died, but eight died of otherdiseases. Three of four cases at autopsy did not show any cancercells in irradiated primary lesions. Four of the 15 patientslived for over five years. The results suggest that a high doseof irradiation delivered by a well-defined proton field couldresult in improved local control and long-term survival in esophagealcarcinoma without undue risk of injury to primary and adjacentorgans.  相似文献   
96.
Laryngopharyngeal reflux disease (LPRD) with nocturnal recovery of gastric acid secretion (nocturnal acid breakthrough: NAB) with proton pump inhibitors (PPI) was first reported. A 79-year-old Japanese woman complained of globus pharyngeus and mild heartburn was examined with the use of tetra-probe 24-h pH monitoring. She had been treated for reflux esophagitis (GERD) for 12 months prior to her visit to our office. She took Lansoprazole (30 mg/day) before dinner every day. The tetra-probe 24-h pH monitoring revealed that the recovery of gastric acid secretion occurred 6.5 h after taking the dose of PPI. The intragastric pH dropped < 4 at about 23:00 and remained below that level for 4 h and 50 min. The 24-h pH-metry at each probe showed that the nocturnal recovery of gastric acid secretion with PPI (NAB on PPI) influenced gastroesophageal and laryngopharyngeal refluxes. The symptoms of the pharynx and esophagus disappeared after taking H2 receptor antagonist (H2RA) additionally before bedtime.  相似文献   
97.
PURPOSE: To examine the relationship between hippocampal volumes, 1H magnetic resonance spectroscopy (MRS)-identified hippocampal metabolic function, and verbal memory in patients with unilateral mesial temporal lobe epilepsy (MTLE). METHODS: Hippocampal volumes, 1H MRS-derived hippocampal creatine to N-acetylaspartate (Cr/NAA), and verbal memory assessment were obtained preoperatively in 22 patients (six right, 16 left) with EEG-defined unilateral MTLE. RESULTS: Left hippocampal volume correlated significantly with left hippocampal Cr/NAA (r=-0.549, p < 0.01), whereas right volume correlated significantly with right Cr/NAA (r=-0.478, p < 0.05). Verbal memory correlated significantly with left hippocampal Cr/NAA (r=-0.594, p < 0.01), but not with left hippocampal volume or right hippocampal measures. CONCLUSIONS: Hippocampal volumes and 1H MRS-derived metabolite ratios are statistically related, but share only a small percentage of variance, suggesting separate but related pathophysiologic processes. Left hippocampal Cr/NAA appears to be more sensitive to verbal memory function than volumes.  相似文献   
98.
Purpose: We have examined the effects of proton irradiation on the histologic and receptive field properties of thalamic relay cells in the cat visual system. The cat lateral geniculate nucleus (LGN) is a large structure with well–defined anatomical boundaries, and well–described afferent, efferent, and receptive field properties.

Methods and Materials: A 1.0-mm proton microbeam was used on the cat LGN to determine short-term (3 months) and long-term (9 months) receptive field effects of irradiation on LGN relay cells. The doses used were 16-, 40-, and 60-gray (Gy).

Results: Following irradiation, abnormalities in receptive field organization were found in 40- and 60-Gy short-term animals, and in all of the long-term animals. The abnormalities included “silent” areas of the LGN where a visual response could not be evoked and other regions that had unusually large or small compound receptive fields. Histologic analysis failed to identify cellular necrosis or vascular damage in the irradiated LGN, but revealed a disruption in retinal afferents to areas of the LGN.

Conclusions: These results indicate that microbeam proton irradiation can disrupt cellular function in the absence of obvious cellular necrosis. Moreover, the area and extent of this disruption increased with time, having larger affect with longer post-irradiation periods.  相似文献   

99.
BACKGROUND: Quadruple therapy provided inadequate eradication rate when given twice-a-day at breakfast and evening meals. AIM: To test twice daily (mid-day and evening) quadruple therapy for Helicobacter pylori eradication. METHODS: This was a single-centre pilot study in which H. pylori-infected (positive histology and culture and RUT) patients were given 2 x 250 mg of metronidazole and 2 x 250 mg of tetracycline, two Pepto-Bismol tablets, plus one 20 mg rabeprazole tablet twice-a-day for 14 days. H. pylori status was confirmed 4 or more weeks after the end of therapy. RESULTS: Thirty-seven patients including 3 with peptic ulcer disease, 19 asymptomatic infected, 4 GERD, and 11 with NUD. Mid-day quadruple therapy was successful in 92.3% (95% CI: 79-98%) including 96.2% of those with metronidazole-susceptible strains, and in 83.3% (10/12) of those with metronidazole-resistant H. pylori. Compliance was 100% by pill count except in one individual who stopped medication after 12 days because of side-effects and who failed therapy. Moderate or greater side-effects were experienced by five patients. CONCLUSION: Twice-a-day, mid-day, quadruple therapy proved effective using the combination of bismuth subsalicylate and rabeprazole instead of bismuth subcitrate and omeprazole. Detailed studies of different formulations (e.g. 2 x 250 mg versus 1 x 500 mg of metronidazole or tetracycline) and timing of administration (breakfast and evening meal versus mid-day and evening meals) may result in significant improvements in H. pylori eradication regimens.  相似文献   
100.
Midfield proton magnetic resonance spectroscopy (MRS) provides a noninvasive method to monitor glutamate and glutamine (Glx) levels in vivo. Experiments to detect the γ and β resonances of Glx have been performed by using commercial 0.5 T and 1.5 T MR scanners on seven patients with elevated blood ammonia and eight normal volunteers. Compared with the spectral sensitivity obtained on an otherwise identical system operating at 1.5 T, the singlet resonance of N-acetyl aspartate (NAA) was decreased by a factor of 1.48, which is significantly less than expected using the ratio of Boltzman populations at the two field strengths. However, the resonances of Glx at 0.5 T increased in signal-to-noise ratio (SNR) by a factor of 2. The increased SNR of Glx is principally due to improved B 0 main-field homogeneity and collapse of the strongly J -coupled Glx resonances. Our preliminary results suggest that midfield proton MRS will provide significant clinical utility in the detection of Glx levels in human brain.  相似文献   
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