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11.
Dietary intake was assessed among 431 black, white, and Mexican American men and women in southeast Texas using 24-hour dietary recall interviews. These data were collected to provide information on ethnic-specific food sources of selected nutrients; this information was used to construct a food frequency questionnaire for a study of nutrient intake and cancer. Nutrient content of total fat, total vitamin A, and vitamin C was determined for all foods consumed and was aggregated across unique food codes. These aggregated food codes were then ranked according to the contribution of each food to the total population intake of each nutrient. Ethnic differences existed in food sources of nutrients that would not be identified if data from only the analysis of the combined data set were used. Generally, however, the food sources identified from analyses of the combined data set included those foods that were important nutrient sources for each of the ethnic groups as well.  相似文献   
12.
目的:观察对胃溃疡复发有较好疗效的健胃愈疡颗粒对溃疡黏膜乳腺癌相关肽和血小板活化因子表达的影响,分析其可能的作用机制。方法:实验于2005-07/2006-07在湘雅医院中心实验室完成。SD大鼠110只,雌雄各半,随机抽签法分为5组,即正常对照组、假手术组、雷尼替丁组、健胃愈疡组,各20只;模型组30只。以Okabe改良法复制大鼠实验性胃溃疡,假手术组仅以生理盐水代替乙酸注入玻管内。造模后24h,雷尼替丁组、健胃愈疡组大鼠分别灌服盐酸雷尼替丁和健胃愈疡颗粒(药物组成为:柴胡、党参、白芍、延胡索、白芨、珍珠层粉、青黛、甘草,湖南湘雅制药有限公司生产)药液10mL/kg,分别相当于2.70,1.62g/kg,1次/d。假手术组、模型组灌服蒸馏水10mL/kg。10d后各组中随机取出10只大鼠剖腹取胃(处死前大鼠禁食24h),90d时将模型组20只大鼠再分为模型复发组和模型非复发组,各10只;除正常对照组、假手术组、模型非复发组大鼠腹腔内注射生理盐水外,其余各组大鼠腹腔内注射白细胞介素1,1μg/kg;在注射48h,大鼠禁食24h后,剖腹取胃。观察其对胃溃疡大鼠胃黏膜氨基己糖及磷脂含量、溃疡指数和胃黏膜血流的影响,并用RT-PCR观察乳癌相关肽乳癌相关肽和血小板活化因子表达的变化。结果:实验动物110只,全部进入结果分析。①模型组10,92d胃黏膜血流均低于正常对照组(P<0.01);健胃愈疡组同期胃黏膜血流均高于模型组(P<0.01)。②健胃愈疡组和雷尼替丁组10d溃疡指数均低于模型组(P<0.01,P<0.05);模型复发组、健胃愈疡组和雷尼替丁组92d溃疡指数均高于模型组(P<0.01);健胃愈疡组10,92d溃疡指数及复发率均低于雷尼替丁组(P<0.05,P<0.01)。③模型组10,92d氨基己糖和磷脂含量均低于正常对照组(P<0.01)。健胃愈疡组10,92d氨基己糖和磷脂含量均高于模型组和雷尼替丁组(P<0.01)。溃疡指数与氨基已糖、磷脂含量呈负相关(r=-0.957,-0.960,P<0.01)。④健胃愈疡组和雷尼替丁组10d乳癌相关肽mRNA表达较正常组和假手术组提高,血小板活化因子mRNA的表达下调(P<0.01),健胃愈疡组两指标表达变化较雷尼替丁组显著(P<0.01);模型复发组、健胃愈疡组和雷尼替丁组92d乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异无显著性意义(P>0.05);模型组乳癌相关肽mRNA、血小板活化因子mRNA的表达同组10d比较差异有显著性意义(P<0.01)。结论:健胃愈疡颗粒可提高乳癌相关肽mRNA及下调血小板活化因子mRNA的表达,影响胃黏膜氨基己糖及磷脂含量,可能是其促进溃疡愈合的机制之一。  相似文献   
13.
The prevalence of obesity among Hispanic American populations is generally greater than among white populations in the United States. Among Mexican Americans, the prevalence of obesity was higher than among either Cuban Americans or Puerto Ricans. It is well known that the prevalence of diabetes increases with increasing levels of obesity or body mass index. However, it does not appear that the high prevalence of obesity in Mexican Americans completely accounts for the higher prevalence of diabetes seen in this ethnic group. Among Mexican Americans, the association of selected cardiovascular disease risk factors, high-density lipoprotein cholesterol subfractions and systolic blood pressure, was similar to that seen among other U.S. populations. Individuals with diabetes had higher values than seen among those without diabetes. In a comparison of nutrient intake in two Mexican-American populations, one rural and one urban, there were no major differences other than higher calorie intakes in the rural population compared with the urban population. In addition, the diet in the rural population, based on higher levels of the Keys score, was more atherogenic than that of the urban population.  相似文献   
14.
重症监护病房革兰阴性菌耐药现状研究   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:了解我院重症监护病房分离菌株对常用抗生素的耐药现状。方法:采用琼脂双倍稀释法测定从我院重症监护病房分离的230株革兰阴性菌的最低抑菌浓度(MIC),并采用抑制剂增强的纸片扩散法测定大肠埃希菌和肺炎克雷伯菌超广谱β-内酰胺酶(ESBLs)。结果:50株肺炎克雷伯菌和17株大肠埃希菌中ESBLs阳性率为62.1%。阴沟肠杆菌、产ESBLs的大肠埃希菌和肺炎克雷伯菌对三代头孢、庆大霉素、阿米卡星的耐药率≥50%。而对碳青霉烯类非常敏感。铜绿假单胞菌对各种抗菌药物均有一定的耐药性。嗜麦芽寡养单胞菌对碳青霉烯类耐药率达100%。结论:受试的230株革兰阴性菌对三代头孢、复合青霉素、氨基糖苷类和环丙沙星的总耐药率≥30%。CPZ/SB和头孢吡肟、碳青霉烯类耐药率较低。  相似文献   
15.
一种用于筛选降血糖及降血脂药物的动物模型   总被引:6,自引:0,他引:6  
一种用于筛选降血糖及降血脂药物的动物模型刘京,申竹芳,刘海帆,叶菲,谢明智(中国医学科学院药物研究所,中国协和医科大学北京100050)糖尿病为常见病和多发病,同时伴有多方面的并发症,脂质代谢紊乱即其中之一。这就要求治疗糖尿病时,除控制病人的血糖外,...  相似文献   
16.
17.
Seventeen to 20 years of mortality follow-up were used to study the relation of leisure time physical activity (LTPA) to coronary heart disease mortality and to all-cause mortality in white male US railroad workers (n = 3,043). This cohort was initially examined from 1957 to 1960, reexamined from 1962 to 1964, and followed until 1977 or death. LTPA was ascertained by a precursor of the Minnesota Leisure Time Physical Activity Questionnaire. The risk estimate for coronary heart disease death, after adjusting for age, was 1.39 for sedentary men who expended 40 kcal/wk in LTPA compared with very active men who expended 3,632 kcal/wk. This relation was attenuated by adjusting for other coronary heart disease risk factors, but it remained independent and significant. Caloric expenditure in light and moderate activity, as well as that performed in any intense activity, showed independent relations to cardiovascular death and all-cause mortality. Associations were slightly stronger in occupationally sedentary men. These results support the hypothesis that physical activity protects against death from coronary heart disease and all-cause mortality.  相似文献   
18.
19.
氯化四乙基铵及维拉帕米对家兔缺血心肌不应期的影响   总被引:1,自引:0,他引:1  
实验比较了K+通道阻断剂氯化四乙基铵(TEA)及Ca2+通道阻断剂维拉帕米(verapamil,Ver)对家兔缺血性心室肌不应期(ERP)的影响。结果表明,阻断冠脉10min及30min后,缺血中心区(CIZ)和缺血边缘区(BIZ)心肌ERP比缺血前均明显缩短,而TEA和Ver均能延长急性缺血性心肌的ERP,可能对心肌缺血引起的心律失常有预防作用。  相似文献   
20.
The objective of this study was to determine visual quality, diagnostic accuracy, and surgical merits of small diameter laparoscopy (SDL). Thirty-seven patients were randomly selected. The indications for laparoscopy were infertility, desire for tubal sterilization or chronic pelvic pain. Patients underwent SDL, followed by conventional laparoscopy (CL) as a control under general anaesthesia. Findings at operation were compared. The mean time for diagnostic work-up was longer with SDL than CL, 11.7 +/- 5.6 versus 7.6 +/- 3.2 min respectively (P < 0.04). Visual quality was scored from 4 to 1 by the operator; mean visual quality, mean endometriosis score and mean adnexal adhesions score were slightly lower with SDL than CL. Sensitivity of SDL in diagnosing endometriosis, adhesions, ovarian, uterine and pouch of Douglas lesions were 71, 58, 81, 89 and 73% respectively; specificity was 100, 96, 100, 100, 100% in the same order. Suction irrigation, cyst aspiration, tissue biopsies, simple adhesiolysis, tubal ligation and cauterization were easily performed with SDL. We conclude that SDL seems a good alternative to CL in diagnosing macro-pelvic anatomy and coarse pelvic pathologies and may also be good in performing surgical procedures such as: tubal ligation, biopsies and differential diagnosis of pelvic fluids. But SDL must be used cautiously in micro-oriented, functional conditions such as infertility, pelvic pain, endometriosis and adhesion scoring or treatment. SDL may be regarded as a less invasive but less sensitive tool with limited surgical merits.   相似文献   
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