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951.
目的 应用复合聚合酶链反应 (复合 PCR) -膜芯片技术快速检测结核分枝杆菌对链霉素 ( SM)的耐药性。方法 设计与合成用于检测结核分枝杆菌耐 SM基因 rps L和 rrs的寡核苷酸探针制作膜芯片 ,与结核分枝杆菌分离株生物素标记的 rps L和 rrs基因复合 PCR产物进行反向斑点杂交 ,并与 PCR-单链构象多态性 ( PCR- SSCP)和 PCR-直接测序 ( PCR- DS)结果比较。结果 5 2株结核分枝杆菌临床分离株中 ,9株敏感株rps L和 rrs基因的 SSCP图谱、膜芯片杂交结果与标准株完全相同 ;4 3株耐 SM菌株中 ,33株存在 rps L 基因4 3位密码子 AAG→ AGG突变 ,5株有 rrs基因 5 13位 A→C突变 ,1株有 rrs基因 5 13位 A→ T突变 ,突变率为 90 .7%。结论 膜芯片技术检测结核分枝杆菌耐 SM基因型灵敏度高、特异性强、简便、快速 ,可用于临床耐药性检测 相似文献
952.
2002年临床常见革兰氏阴性杆菌耐药性监测 总被引:8,自引:1,他引:8
目的 调查国家细菌耐药性监测网临床常见革兰氏阴性杆菌对各种抗菌药物的耐药性现状。方法 药物敏感性试验采用纸片扩散法 ,耐药性数据分析采用 WHONET5软件。结果 2 0 0 2年国家细菌耐药性监测网 8个省、市、自治区的 5 7家三级甲等医院共收集患者首次分离株 2 4 82 6株 ;大肠埃希氏菌、铜绿假单胞菌和肺炎克雷伯氏菌是最常见菌。主要标本为痰、尿和伤口及分泌物 ,分别占全部标本的 4 7.9% ,16 .8%和 10 .4 %。绝大多数肠杆菌科细菌对亚胺培南和美罗培南敏感 ,其次为第三代头孢菌素、含酶抑制剂的头孢菌素及阿米卡星。 15 % (15 .6 %~ 5 1.2 % )的肠杆菌、柠檬酸杆菌、沙雷氏菌和普罗威登氏菌对第三代头孢菌素耐药。除大肠埃希氏菌外 ,环丙沙星和左氧氟沙星对其他肠杆菌科细菌的耐药率低于 30 % (6 .0 %~ 2 9.7% ) ;产超广谱β-内酰胺酶 (ESBL s)的大肠埃希氏菌和肺炎克雷伯氏菌株的检出率分别为 18.2 %和 2 2 .6 % ;铜绿假单胞菌对亚胺培南和美罗培南的耐药率分别为 19.1%和 15 .2 %。鲍氏不动杆菌对碳青霉烯类抗生素较敏感 ,但对头孢哌酮、头孢他啶和阿米卡星的耐药率分别为 5 2 .8% ,4 1.6 %和 31.8%。结论 细菌耐药性问题是抗感染治疗的主要威胁 ,合理使用抗菌药物以降低耐药性和采取有效措 相似文献
953.
抗菌药物联用对耐甲氧西林金黄色葡萄球菌体外抗菌活性研究 总被引:6,自引:1,他引:6
目的了解万古霉素与头孢哌酮/舒巴坦、亚胺培南、左氧氟沙星联用对MRSA的体外抗菌活性,指导临床合理用药。方法常规方法培养分离细菌,用VITEK微生物自动分析仪或API系统鉴定到种。MRSA鉴定应用乳胶凝集试剂盒,药敏试验采用肉汤倍比稀释法和琼脂平板稀释法。结果万古霉素对40株MRSA的MIC90为4mg/L,而与头孢哌酮/舒巴坦、亚胺培南、左氧氟沙星联用MIC90降为0.25~1mg/L。结论万古霉素与上述三种药物联用以协同作用为主,抗菌活性提高4倍以上。临床上治疗由MRSA引起的重症感染应根据药敏试验结果采用万古霉素与亚胺培南或头孢哌酮/舒巴坦或其它抗菌药物联合应用。 相似文献
954.
:探讨医院工儿得性肺炎至肺炎致病菌的分布及耐药性。方法:对360例医院获得性肺炎105例患者痰及血标本中的124株非发酵蓖培养及药敏进行分析。结果;非发酵菌占总菌数41.1%(124/302)。其中,铜绿假单胞菌54株,不动杆菌41株,嗜麦芽窄食单胞菌12株。铜绿假单胞菌对哌拉西林、阿米卡星、头孢哌酮、头孢他啶、亚胺培南、氨曲南、环丙沙星敏感。不动杆菌对包曲松、亚胺培南、环丙沙星敏感。对嗜麦芽窄食 相似文献
955.
We compared the postprandial blood glucose (BG)-levels following preprandial regular insulin or lispro insulin before and
after eating in adolescents with diabetes. Lispro is a rapidly absorbed insulin analogue. Lispro insulin injected immediately
before breakfast reduced the postprandial BG-rise significantly compared to the 20 min preprandially administered regular
insulin (P<0.01). Postprandial lispro injection resulted in similar BG values as the standard treatment with regular insulin 20 min
preprandially.
Conclusion Lispro insulin injected immediately before the meal leads to lower postprandial BG levels and seems to be an option for teenagers
who use multiple preprandial insulin injections. Postprandial lispro administration could be a benefit in certain situations
since it resulted in similar BG values to preprandial regular insulin.
Received: 13 March 1997 / Accepted: 26 May 1997 相似文献
956.
Current advances in rhinomanometry were reviewed in this paper. Active posterior rhinomanometry with a “head-out” body plethysmograph
may be the least invasive method currently available for measuring nasal patency. In general, active anterior rhinomanometry
with a face mask or a nasal nozzle has been employed in various studies throughout the world. Nasal resistance as calculated
from the equationR = 0.78 (ΔP/V)1.33 at any points on a pressure/flow curve, or averaged nasal resistance may be the most suitable expression for nasal patency.
Values for nasal resistance at ΔP 100 Pa in Japanese patients or ΔP 150 Pa in Caucasians have been widely employed as standard objective data for nasal obstruction, although rhinomanometric
results sometimes do not agree with subjective evaluation of nasal obstruction. Nasal airflow acceleration or peak flow index
during nasal breathing at rest can be applied as warranted to confirm an objective diagnosis of symptomatic nasal obstruction.
Further, nationality and anthropological characteristics can be related to the severity and type of stuffiness. 相似文献
957.
The purpose of this study was to determine changes in nasal respiratory pattern with growth and development, particularly to determine the age where upper airway growth ceases. The results on 361 healthy subjects, aged 7 to 24 years, based on aerodynamic measurements during rest breathing, showed clear differences between inspiratory and expiratory phases. Nasal airflow rate and cross-sectional area increased and oral-nasal pressure and nasal resistance decreased with age up to the age of 16, levelling by the age of 20 years. The body size and gender had effect only on nasal airflow rate. This study suggests that the measurements of the nasal respiratory pattern, determining impaired nasal airway, should be done during inspiration and using age-related assesment from a healthy population until the age of 16 years. From then on, guidelines for adults are applicable. 相似文献
958.
Fidel Cano Juan A. García-Velasco Antón Millet José Remohí Carlos Simón Antonio Pellicer 《Journal of assisted reproduction and genetics》1997,14(5):254-261
Purpose: Our purpose was to assess the endocrine status of women with polycystic ovaries (PCO) undergoing IVF, and to compare oocyte
quality with endocrine markers of the syndrome, in an attempt to define a subpopulation with poor quality oocytes.
Methods: This was a retrospective study. Patients were first endocrinologically analyzed: serum levels of androgens (T, androstenedione,
DHEAS), FSH, and LH as well as glucose and insulin after an oral glucose tolerance test (OGTT) were recorded and are expressed
as absolute values and area under the curve (AUC). Subsequently, they were followed over a 2-year period in which patients
underwent several attempts of IVF as well as serving as oocyte donors. Patients were divided into three groups: group I (n=4)
was women who displayed embryos unable to implant in 15 IVF cycles and 10 ovum donation cycles in which they served as donors;
group II (n=16) was PCO patients in whom IVF (n=38) and/or oocyte donation cycles (n=42) resulted in pregnancies; and group
III (n=13) was IVF patients with normal appearance of the ovaries by ultrasound. The endocrine status was compared with the
IVF results.
Results: There was no difference among groups in the endocrinological parameters tested, except for the OGTT which identified women
in group I as having higher serum glucose and insulin levels than patients in groups II and III. Similarly, the OGTT showed
higher serum glucose values in group II compared to group III. Women in group I were also obese. Patients in group III were
older than PCO patients and needed more gonadotropins to reach an ovarian response which resulted in a reduced number of oocytes
retrieved. Fertilization was also impaired in group I, in which no pregnancy was recorded.
Conclusions: This study shows that there is a particular subgroup of PCO patients with lower fertilization rates and embryos unable to
implant. These patients are obese and nonhyperandrogenic and show derangements of insulin secretion. 相似文献
959.
P—糖蛋白在头颈部恶性肿瘤中的表达及意义 总被引:4,自引:0,他引:4
为探讨mdr1基因产物在头颈部恶性肿瘤中的表达状况及其与临床耐药性的关系,作者用免疫组化ABC法47例未化疗的头颈部恶性肿瘤进行P-糖蛋白表达的原位检测,同时应用细胞核仁组成区嗜银蛋白技术(AgNOR)测定了43例肿瘤对8种抗癌药物的敏感性。结果显示,头颈部恶中的P-糖蛋肿瘤中的P-糖蛋白表达阳性率为57%,肿瘤对VCR.ADM.PY<M,MMC4种药物的敏感率在P-糖蛋白阳性组明显低于阴性组,并有统计学意义。 相似文献
960.
4种细胞因子对K562/S及其耐药细胞株K562/A02积蓄柔红霉素的影响 总被引:2,自引:0,他引:2
目的通过检测4种常用细胞因子对白血病细胞株K562/S及其多药耐药细胞株K562/A02积蓄柔红霉素(DNR)能力的影响,评价细胞因子在抗白血病细胞多药耐药性方面的应用前景。方法用流式细胞仪及荧光法检测重组人α-干扰素(IFN-α)、白细胞介素2(IL-2)、肿瘤坏死因子(TNF)、重组人粒-单集落刺激因子(GM-CSF)对K562/S及K562/A02积蓄柔红霉素能力的影响。结果IL-2、TNF、GM-CSF作用后K562/S及K562/A02细胞株对柔红霉素的积蓄无改变,而IFN-α可显著提高耐药细胞系K562/A02细胞内DNR浓度,在150min时升高了4.01倍(P<0.05)。结论小剂量(500U/ml) α-干扰素作用后,多药耐药细胞株 K562/A02对抗肿瘤药物DNR的积蓄作用大大提高,提示IFN-α具有提高耐药细胞株细胞内药物浓度、恢复其药物敏感性、逆转多药耐药性的作用。 相似文献