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41.
目的:探讨家兔阴茎感觉神经来源。方法:健康成年雄性新西兰白兔12只,随机均分为两组:每组6只,A组在左侧脊神经上记录,B组在右侧脊神经上记录。对家兔阴茎施加不同大小的机械刺激,用神经单纤维记录技术,在同侧S1~S4脊神经上记录单纤维放电。结果:通过对家兔阴茎施加各种不同机械刺激,在同侧S2~S3脊神经上能记录到放电,S1、S4脊神经上未能记录到放电。左侧脊神经放电纤维数量分别为:S2:39.67±3.14,S3:21.00±2.19;右侧脊神经放电纤维数量分别为:S2:40.00±3.16,S3:19.67±2.58,左右侧差异无显著性(P>0.05)。结论:家兔阴茎皮肤感觉来源于S2~S3脊神经。 相似文献
42.
数字图书馆的个性化信息服务 总被引:6,自引:0,他引:6
分析了国内外数字图书馆个性化信息服务的现状及相关技术,提出了建立个性化信息服务系统的方法及个性化信息服务中需要注意的问题. 相似文献
43.
目的探讨乳头溢液的渗断和治疗方法,为合理的治疗提供科学依据。方法回顾分析手术治疗的207例乳头溢液病例资料。结果(1)在非哺乳期间发生乳头溢液多属病理性溢液;(2)通过美蓝法或平针头指示法行区段切除术,安全准确。结论(1)乳头溢液特别足血性溢液应手术治疗.对早期发现和早期治疗乳腺癌有鼋要的临床意义。(2)乳头溢液伴肿块者,不沧年龄大小、溢液性质均应手术治疗。 相似文献
44.
Joan Dolce Dunn 《International journal of nursing knowledge》1998,9(Z2):136-143
PURPOSE. The purpose of the study was to develop a scale to calculate college students' powerlessness regarding health service barriers (PHSB). METHODS. Scale items were generated to represent two domains of interest: powerlessness and college students' powerlessness regarding health service barriers. The final 20-item instrument was subjected to multiple measures of validity with college students and panels of nurse experts in the area of nursing diagnosis. Reliability was assessed by two samples (n = 92 and n = 33) of college-age students. A final administration was conducted with 197 college students. FINDINGS. The PHSB scale was determined to be an accurate and consistent measure. CONCLUSIONS. This instrument will provide a reliable and valid measure to conduct research. 相似文献
45.
Sufentanil and vecuronium are commonly used simultaneously in anaesthesia. Bradycardia and asystole have been described immediately after the administration of these two compounds. Therefore, the purpose of the present study was to evaluate the direct cardiac effects of sufentanil and vecuronium in all parts of the cardiac pacemaker and conduction system.
The electrophysiological effects of sufentanil and vecuronium were studied in isolated spontaneously beating guinea-pig hearts perfused by the method of Langendorff. At a concentration of 0.1 μmol/1 sufentanil a significant reduction of the spontaneous sinus rate, prolongation of atrioventricular, intraventricular and His' bundle conduction could be observed. The highest concentration of 10 μmol/1 of sufentanil led to an overall slowing of conduction velocity and to an profound slowing of spontaneous sinus rate. AV nodal as well as atrial and ventricular refractoriness were markedly prolonged at this high concentration of sufentanil. In contrast, during perfusion with vecuronium at a concentration of 0.1 μmol/1 up to 10 μmol/1 no significant effects on cardiac conduction and pacemaker activity could be observed.
In conclusion, the electrophysiological effects of sufentanil are comparable to that of unspecific calcium antagonists. Therefore, especially in patients with a preexisting damage of the cardiac conduction system, the indirect effect of the combination of sufentanil and vecuronium which is predominantly responsible for bradycardia and asystole may be worsened by the direct effects of sufentanil. 相似文献
The electrophysiological effects of sufentanil and vecuronium were studied in isolated spontaneously beating guinea-pig hearts perfused by the method of Langendorff. At a concentration of 0.1 μmol/1 sufentanil a significant reduction of the spontaneous sinus rate, prolongation of atrioventricular, intraventricular and His' bundle conduction could be observed. The highest concentration of 10 μmol/1 of sufentanil led to an overall slowing of conduction velocity and to an profound slowing of spontaneous sinus rate. AV nodal as well as atrial and ventricular refractoriness were markedly prolonged at this high concentration of sufentanil. In contrast, during perfusion with vecuronium at a concentration of 0.1 μmol/1 up to 10 μmol/1 no significant effects on cardiac conduction and pacemaker activity could be observed.
In conclusion, the electrophysiological effects of sufentanil are comparable to that of unspecific calcium antagonists. Therefore, especially in patients with a preexisting damage of the cardiac conduction system, the indirect effect of the combination of sufentanil and vecuronium which is predominantly responsible for bradycardia and asystole may be worsened by the direct effects of sufentanil. 相似文献
46.
Sociodemographic Differences in the Prevalence of Self-Reported Headache in Icelandic School-Children 总被引:1,自引:0,他引:1
Gúdrun Kristjánsdóttir R.N. M.Sc. Vivian Wahlberg R.N. Dr. Med. Sc. Professor 《Headache》1993,33(7):376-380
SYNOPSIS
The study considers the prevalence of headache experiences in a random national sample of 2140 Icelandic 11-12 and 15-16 year-old school-children. The study finds an overall 21.9% prevalence of "at least weekly" headache. The prevalence is significantly higher among younger children end among girls. The gender difference is found to be related to the fact that older boys have a markedly lower prevalence than younger boys. No gender difference is observed in the younger group. Social class interacts with gender, with the gender difference leveling out in the upper class. The frequency of headache experiences correlates with last months use of medication to relieve headache. The high overall prevalence of headache found in this study agrees with earlier findings, and is a matter of concern since little is being done to counter this problem of discomfort among school-children. 相似文献
The study considers the prevalence of headache experiences in a random national sample of 2140 Icelandic 11-12 and 15-16 year-old school-children. The study finds an overall 21.9% prevalence of "at least weekly" headache. The prevalence is significantly higher among younger children end among girls. The gender difference is found to be related to the fact that older boys have a markedly lower prevalence than younger boys. No gender difference is observed in the younger group. Social class interacts with gender, with the gender difference leveling out in the upper class. The frequency of headache experiences correlates with last months use of medication to relieve headache. The high overall prevalence of headache found in this study agrees with earlier findings, and is a matter of concern since little is being done to counter this problem of discomfort among school-children. 相似文献
47.
Quality and standardization in blood component preparation with an automated blood processing technique 总被引:3,自引:0,他引:3
van Rhenen Vermeij de Voogt Bernes & Payrat 《Transfusion medicine (Oxford, England)》1998,8(4):319-324
The use of automated blood processors in combination with bottom and top blood containers has been found to improve the standardization and quality of blood components. A study was performed to validate a new type of processor (Optipress® II) and compare its performance with a first generation processor (Optipress® I).
Primary separation on the Optipress II was investigated on 570 mL (± 10%) of anticoagulated blood in a nonpaired study. In addition, the quality of the products in routine production was compared between the results of the Optipress I and Optipress II. The whole blood units were kept overnight at room temperature (20 ± 2 °C). Separation was performed under conditions to obtain 55 mL buffy coats with a 50% haematocrit (ht). Platelet concentrate preparation was investigated in a paired study and compared to the routine manual method using PAS II additive solution. Parameters studied were volume, red cell, white cell and platelet counts, ht, haemoglobin (hb, total and free).
Primary separation was more efficient in the Optipress II because the platelet count was lower in the erythrocyte concentrates ( P < 0.0001), platelets were lower in plasma ( P < 0.0001) and platelet counts were higher in buffy coats ( P < 0.0001). Buffy coat volume showed less variation (Optipress II VC = 4%, Optipress I VC = 7.4%). Secondary separation did not show differences between the Optipress II and manual method but was advantageous because of the automatic termination of the procedure.
Further improvement of standardization in blood component preparation is possible with an automated blood processor, leading to improvement of the quality of blood products for patient care. 相似文献
Primary separation on the Optipress II was investigated on 570 mL (± 10%) of anticoagulated blood in a nonpaired study. In addition, the quality of the products in routine production was compared between the results of the Optipress I and Optipress II. The whole blood units were kept overnight at room temperature (20 ± 2 °C). Separation was performed under conditions to obtain 55 mL buffy coats with a 50% haematocrit (ht). Platelet concentrate preparation was investigated in a paired study and compared to the routine manual method using PAS II additive solution. Parameters studied were volume, red cell, white cell and platelet counts, ht, haemoglobin (hb, total and free).
Primary separation was more efficient in the Optipress II because the platelet count was lower in the erythrocyte concentrates ( P < 0.0001), platelets were lower in plasma ( P < 0.0001) and platelet counts were higher in buffy coats ( P < 0.0001). Buffy coat volume showed less variation (Optipress II VC = 4%, Optipress I VC = 7.4%). Secondary separation did not show differences between the Optipress II and manual method but was advantageous because of the automatic termination of the procedure.
Further improvement of standardization in blood component preparation is possible with an automated blood processor, leading to improvement of the quality of blood products for patient care. 相似文献
48.
Shaping ability of the M4 handpiece and Safety Hedstrom Files in simulated root canals 总被引:1,自引:0,他引:1
A. LLOYD A. JAUNBERZINS A. DHOPATKAR S. BRYANT P. M. H. DUMMER 《International endodontic journal》1997,30(1):16-24
The aim of this study was to assess the shaping ability of the M4 reciprocating handpiece and Safety Hedstrom files in simulated canals. A total of 40 simulated canals of various angles and positions of curvature were prepared with an M4 handpiece using Safety Hedstrom files oriented with the ground, flattened surface towards the inner aspect of the curve. A standard regimen was adopted throughout. Pre- and post-operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount and location of resin material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Preparation time varied significantly (P<0.001) between the canal types; overall, 20° canals were prepared more quickly than 40° canals. Zips and elbows were observed in 16 out of the 40 canals with most (11) being created in 40° specimens. Ledges were found in 19 canals and perforations in only 1. There were no significant differences between canal shapes for these aberrations. Excessive removal of material from the inner aspect of the canal at the curve to create a danger zone was found in 20 canals, but only in those with 40° curves. Significant differences in total canal width between the canal types were seen at the zips (P<0.05), elbows (P<0.05) and danger zones (P<0.001). Transportation at the danger zones varied significantly (P<0.001) between canal types. Under the conditions of this study, the M4 handpiece and Safety Hedstrom files created hour-glass preparations in a substantial proportion of canals. In reality, the Safety Hedstrom file with its one flattened surface was ineffective at reducing removal of material along the inner aspect of canal curves in severely curved specimens and clearly has the potential to create strip perforations in teeth. 相似文献
49.
50.
五所医院特需医疗服务状况调查 总被引:1,自引:1,他引:0
通过对上海医科大学附属华山医院、协和医院、北京同仁医院、中山医科大学附属第一医院、浙江医科大学附属第二医院开展的特需医疗服务情况的调查,论述了五所医院的具体做法,在对调查结果进行分析的基础上,就特需医疗服务的管理提出了建议。 相似文献