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51.
An autoregressive model for the analysis of longitudinal data was applied in the context of investigating the effect of bronchial responsiveness on the growth of pulmonary function in children. In the model used, the correlation between pulmonary function values within an individual decreases exponentially as the time between visits increases. The model incorporates both fixed and time-dependent covariates in a unified fashion and does not require complete data in all visits for each individual. Furthermore, the change in pulmonary function is not assumed to be linear over time. Using response to cold air data as a measure of bronchial responsiveness, we found that children who responded to cold air have a slower rate of growth in pulmonary function. In addition, the data suggested that the effect of cigarette smoking may be greater as the response to cold air increases. Extensions of the autoregressive approach to other correlation structures and to the case of unequidistant observations are discussed.  相似文献   
52.
Widely used dichotomous categorical measures of pregnancy intentions do not represent well the complexity of factors involved in women's intentions. We used a variety of exploratory statistical methods to examine measures of pregnancy intention in the 2002 National Survey of Family Growth (N = 3,032 pregnancies). Factor analyses identified two key dimensions of pregnancy intentions (desire and mistiming) and two smaller nondimensional categories (overdue and don't care). Desire included both affective and cognitive variables, as well as partner-specific factors. Similar pregnancy-intention dimensions were found for adolescent and adult women, across socioeconomic status, and among racial and ethnic groups. Both desire and mistiming were highly predictive of the decision to abort or continue the pregnancy. These analyses strongly support prior demographic thinking about the importance of both the timing of pregnancy and wanting a baby, but suggest that multidimensional rather than simple categorical measures of pregnancy intentions should be used.  相似文献   
53.
Fifty-seven teachers of nursing, who comprised 42 women and 15 men and who also comprised 12 senior tutors, 16 nurse tutors and 29 clinical teachers, participated in a study to evaluate a workshop which they attended.
The method of inquiry used was that of a survey by questionnaire. Two questionnaires were used, one being set at the beginning of the workshop and the other at the end of the proceedings. The learning objectives for the workshop were used as the questionnaire items and comprised 20 in all. When the before and after scores relating to the questionnaire items were compared through the use of t tests significant differences were found on 12 out of the 20 objectives. In the course of the paper the differences found are identified and discussed. Some of the limitations of the method of inquiry used are discussed and finally some conclusions are reached.  相似文献   
54.
Detailed invasive haemodynamic studies were performed in 27of 32 patients with severe tetanus. Nineteen had severe uncomplicatedtetanus and eight had associated major complications, chieflyinfection and pulmonary complications. The results were comparedwith those obtained from 15 healthy male volunteers who servedas controls. There were two deaths in 32 patients (mortality6.25 per cent). Severe tetanus without major complications wascharacterized by a high output hyperkinetic circulatory statewith tachycardia (heart rate 131 (19.2) beats/minute), increasedstroke volume index (43.1 (10.7) ml/m2), increased cardiac index(5.48 (0.94)1/min/m2) and a normal left ventricular stroke workindex (60.5 (15.9) g/m/m2). Volume loading demonstrated a significanthaemodynamic response and increased vascular capacitance. Evenso the maximum percent rise from baseline values of these indicesafter volume load was significantly higher in controls (p <0.001). Autonomic cardiovascular disturbances affected bothsympathetic and parasympathetic activity. Hypertension and tachycardiaalternating with hypotension and bradycardia were related tosudden fluctuations in systemic vascular resistance. Our studiessuggested some degree of myocardial dysfunction in patientswith severe uncomplicated tetanus. The haemodynamics of severetetanus were masked and altered by complicating infection, pneumonia,and atelectasis.  相似文献   
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56.
Objectives Strong linkages exist between childhood abuse and adult intimate partner violence (IPV) among women in developed countries. Few studies examine this pattern in developing nations. This study explores the effect of childhood physical and/or psychological abuse on the likelihood of IPV among a national sample of Ecuadorian women of reproductive age. Methods Secondary data analysis was conducted on a subsample of 9,077 Ecuadorian women, utilizing the 2004 Encuesta Demografía y de Salud Materna e Infantil survey. Cross-tabulations and multivariate logistic regression models were utilized to assess whether women who report childhood abuse had a higher likelihood of reporting sexual, physical or psychological IPV during their lifetimes or within the past year. Results Levels of abuse were high. More than 30% of women reported childhood psychological or physical abuse, and 21% experienced both types of abuse. Forty percent of women reported sexual, physical or psychological IPV during their lifetimes, while 15% reported any form of IPV in the past year. The co-occurrence of childhood psychological and physical abuse was highly predictive of all forms of IPV, with less consistent associations for women who reported only physical or only psychological childhood abuse. Conclusions This study suggests that childhood abuse is an important risk factor for IPV victimization among Ecuadorian women. While this analysis supports findings from developed countries, more cross-cultural research about patterns of violence throughout the life course is needed to develop relevant prevention programs.  相似文献   
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58.
A cross sectional study was done between October 1999 and February 2000 to determine antimicrobial susceptibility patterns of consecutive bacterial isolates of 102 clinical samples among surgical in-patients at Lilongwe Central Hospital (LCH), Malawi. Antimicrobial susceptibility was determined using comparative disc diffusion techniques. 83 (81.4%) samples were culture positive for bacterial growth while 19 (18.6%) grew nothing. Of the 93 culture positive specimens, Staphylococcus aureus was the predominant organism 43(51.8%) followed by Proteus species 8(9.6%) and E. coli 7(8.4%). Overall, 98.6% of all isolates tested against ciprofloxacin were susceptible, and against gentamicin and flucloxacin were 84.8% and 66.7% respectively. 59.3% of isolates tested against chloramphenicol were resistant. We recommend a review on the use of chloramphenicol as first-line antimicrobial therapy among surgical in-patients at Lilongwe Central Hospital. We also recommend restricted use of antimicrobials so as to minimise development of drug resistance. Periodic susceptibility studies are necessary to guide judicious use of antibiotics.  相似文献   
59.
d-生物素的立体专一性全合成研究   总被引:1,自引:0,他引:1  
对confaione的d-生物素(1)全合成进行了改进,从半胱氨酸计算,总收率3.7%。5与4-溴代三苯膦丁酸甲酯进行Wittig-Schlosser缩合反应可立体专一性地转化成反式-烯(6)。以叠氮三甲基硅烷代替叠氮化锂亲核进攻9分子中C3-溴原子,可显著地提高顺式-叠氮内酰胺10的收率。  相似文献   
60.
侵及眶部脑肿瘤的临床特征与显微手术处理   总被引:2,自引:1,他引:1  
目的 研究侵及眶部的脑肿瘤临床特征与显微外科手术治疗效果。方法 对58例本病经临床分析与影像学检查而获诊断,采用不同手术入路及显微外科技术切除肿瘤。全组病例中,肿瘤位于前颅凹50例,中颅窝8例,均侵及眶腔。其中39例(67.2%)有头痛、头晕等颅内压增高表现,54例(93.1%)出现视器症状。结果 本组46例肿瘤(79.3%)获手术全切除,12例(20.7%)为次全切除,无死亡。对48例经信访或门诊随访6个月-9年(平均3.6年),39例(81.3%)恢复满意,余9例(18.7%)有不同程度后遗症。结论 脑肿瘤侵及眶部多以视器改变为主要临床表现。采取不同手术入路、以显微外科技术切除本类肿瘤,预后良好。  相似文献   
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