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1.
This study was conducted to assess the effect of sevoflurane on lung resistance and compliance, and its responsiveness to histamine. We studied eight dogs to compare the effect of sevoflurane, isoflurane, enflurane, and halothane on bronchoconstriction caused by histamine. Baseline values of pulmonary resistance (RL) and dynamic pulmonary compliance (Cdyn) were measured prior to administration of histamine. Histamine (2, 4, and 8 μg · kg−1) were administered iv, and the values of RL and Cdyn at the time of peak effect were recorded. Under 1 or 2 MAC anaesthesia, sevoflurane as well as the other three anaesthetics had no bronchoactive effects. The four anaesthetics, including sevoflurane, demonstrated inhibitory effect on increases in RL and decreases in Cdyn caused by histamine. At 1 MAC anaesthesia, % changes in RL caused by 2, 4, or 8 μg · kg−1 of histamine were 38 ± 11, 85 ± 21, or 132 ± 24% (mean ± SE) for halothane, and 65 ± 11, 132 ± 15, or 172 ± 19% for sevoflurane, respectively. Sevoflurane was less effective than halothane in preventing increases in RL. In preventing decreases in Cdyn, sevoflurane was less effective than halothane only at 8 μg · kg−1 of histamine under 1 and 2 MAC anaesthesia. There was no difference in attenuating effect on changes in RL and Cdyn between sevoflurane and isoflurane or enflurane. We concluded that sevoflurane was less potent than halothane in attenuating changes in RL and Cdyn in response to iv histamine. Cette étude a été réalisée dans le but d’évaluer les effets du sévoflurane sur la résistance et la compliance pulmonaires en réponse à l’histamine. Les effets du sévoflurane, de l’isoflurane, de l’enflurane et de l’halothane sur la bronchoconstriction induite par l’histamine sont comparés sur huit chiens. Avant l’administration d’histamine, on mesure les valeurs initiales de la résistance (RL) et de la compliance dynamique (Cdyn) pulmonaires. L’histamine (2, 4, 8 μg · kg−1) est administrée par la voie veineuse et les valeurs maximales de la RL et de la Cdyn sont enregistrées. Les quatre anesthésiques, dont le sévoflurane inhibent l’augmentation de la RL et la diminution de la Cdyn provoquées par l’histamine. A MAC 1 d’anesthésie, les pourcentages de changement de RL produits par 2, 4, ou 8 μg · kg−1 d’histamine sont respectivement de 38 ± 11, 85 ± 21, ou 132 ± 24% (moyenne + SD) pour l’halothane, et de 65 ± 11, 132 ± 15, ou 172 ± 19% pour le sévoflurane. Le sévoflurane est moins efficace que l’halothane pour prévenir les augmentations de RL. Le sévoflurane est moins efficace pour prevenir la diminution de Cdyn mais seulement à 8 μg · kg−1 d’histamine sous anesthésie à MAC 1 et 2. Le sévoflurane, l’halothane et l’isoflurane ne sont pas de différents pour amortir les changements de RL et Cdyn. Nous concluons que le sévoflurane est moins puissant que l’halothane pour diminuer la réponse à l’histamine de la RL et de la Cdyn.  相似文献   
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目的比较5French(5F)及6French(6F)导引导管在经桡动脉冠状动脉介入治疗(TRI)患者中的安全性及有效性。方法共纳入2009年2月至2010年3月患者,收集相关资料录入数据库,包括患者基线临床资料、导引导管的尺寸、靶血管、靶病变的特点、手术的成功率、手术失败原因、经桡动脉冠状动脉介入治疗手术的成功率及失败原因、患者住院期间主要不良心血管事件率及术后桡动脉闭塞率。结果连续纳入患者共185例,接受195次经桡动脉冠状动脉介入治疗术,平均年龄(57±11)岁(33~81岁);其中54例患者纳入6F导引导管组,共进行56次手术,治疗89处病变;138例患者纳入5F导引导管组,共行146次手术,治疗231处病变。AHA B2/C型病变比例在两组间差异无统计学意义(5F组43.7%/29.0%比6F组46.1%/34.6%,P>0.05),但慢性闭塞性病变、分叉病变、钙化病变5F组显著少于6F组(5.6%比14.6%,P=0.005;23.4%比37.1%,P=0.012;9.5%比47.2%,P<0.001);组间的手术时间[(45±21)min比(46±19)min)]、手术X线曝光时间[(15±12)min比(16±13)min]、使用造影剂量[(140±45)ml比(156±56)ml]差异均无显著统计学意义(P>0.05),但是5F组造影剂用量有减少的趋势(P=0.066);组间住院时间[(1.40±1.26)d比(1.29±0.69)d]和手术成功率(95.2%比94.6%)也差异无统计学意义(P>0.05);5F组1例患者术后桡动脉闭塞,6F组无患者术后桡动脉闭塞(P=1.0),5F组1例发生卒中。结论经桡动脉冠状动脉介入治疗,即使是复杂及高危冠脉病变,5F导引导管有效、安全,手术成功率不低于常规使用的6F导引导管;换用5F导引导管进行冠状动脉介入治疗是一种有吸引力的选择。  相似文献   
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Oral Diseases (2012) 19 , 46–58 Sjögren’s syndrome (SjS) is one of the most common autoimmune rheumatic diseases, clinically characterized by xerostomia and keratoconjunctivitis sicca. We investigated the following controversial topics: (i) Do we have reliable ways of assessing saliva production? (ii) How important are the quantity and quality of saliva? (iii) Are only anti‐SSA/Ro and anti‐SSB/La relevant for the diagnosis of SjS? (iv) Are the American‐European Consensus criteria (AECC) the best way to diagnose SjS? Results from literature searches suggested the following: (i) Despite the fact that numerous tests are available to assess salivation rates, direct comparisons among them are scarce with little evidence to suggest one best test. (ii) Recent developments highlight the importance of investigating the composition of saliva. However, more research is needed to standardize the methods of analysis and collection and refine the quality of the accumulating data. (iii) In addition to anti‐Ro/La autoantibodies, anti α‐fodrin IgA and anti‐MR3 autoantibodies seem to be promising diagnostic markers of SjS, but more studies are warranted to test their sensitivity and specificity. (iv) AECC are classification, not diagnostic criteria. Moreover, recent innovations have not been incorporated into these criteria. Consequently, treatment directed to patients diagnosed using the AECC might exclude a significant proportion of patients with SjS.  相似文献   
6.
Cross‐matching of records between Singapore's tuberculosis and HIV registries showed that 3.3% of individuals with tuberculosis (TB) were coinfected with HIV (2000?2014), the TB incidence among individuals with HIV infection was 1.65 per 100 person‐years, and 53% of coinfections were diagnosed within 1 month of each other. The findings supported joint prevention programmes for early diagnosis and treatment.  相似文献   
7.
It is generally considered that in complete right bundle branch block, the electrocardiographic standard for the diagnosis of right ventricular hypertrophy is not applicable. According to Cohen's criteria, right ventricular overload exists if thallium-201 myocardial perfusion demonstrates the right ventricular wall, and in this light we attempted to reassess the validity of the electrocardiographic standard for right ventricular hypertrophy. Twenty-three children with complete right bundle branch block (abbreviated as CRBBB) were evaluated. The agreement and disagreement ratios of the electrocardiographic standard with Cohen's criteria was 20/23 and 3/23 respectively. Even in patients without intracardiac anomalies, right ventricular overload was suspected by Cohen's criteria. The electrocardiographic standard was in agreement with Cohen's criteria in most of these patients.  相似文献   
8.
Cerebral aneurysm may occur in some cases of major cerebral artery occlusion. However, according to our search of the literature, only four cases of aneurysmal subarchnoid hemorrhage (SAH) associated with bilateral common carotid artery occlusion (CCAO) have been reported in addition to the case we report here with a summary of the previously reported cases. A healthy 82-year-old female was found unconscious and admitted to our hospital where her neurological state was diagnosed as Hunt & Kosnik grade II, World Federation of Neurosurgical Societies grade II. General physical examination yielded no abnormal findings. A computed tomography (CT) scan of the head revealed a subarachnoid hemorrhage (Fisher's classification group 3). An aortogram demonstrated the presence of both vertebral arteries (VA), but the origins of the common carotid arteries (CCAS) were not visible at all. The left vertebral angiogram (VAG) revealed anastomosis between the muscle branch of the VA and the occipital artery, with retrograde blood flow through the external carotid artery supplying the internal carotid artery (ICA). These findings were also visible on the right VAG, but there was severe stenosis of the C2 portion of the right ICA. The right enlarged posterior communicating artery (Pcom) supplied the right ICA. Two saccular aneurysms arising from the junction of the right posterior cerebral artery (PCA) and the enlarged right Pcom and the P2 segment of right PCA, respectively were also observed. Aneurysm formation in this case was probably caused by hemodynamic stress secondary to bilateral CCAO induced by arteriosclerosis.  相似文献   
9.
Purpose. CO2 absorbents convert sevoflurane to fluoromethyl-2,2-difluoro-1-(trifluoromethyl) vinyl ether (compound A), whose toxicity in rats raises concern regarding the safety of sevoflurane in a low-flow system. The type of CO2 absorbent is one of factors that affect compound A concentration in the anesthetic circuit. The aim of the present study was to investigate the concentration of compound A in an anesthetic model circuit following the use of different brands of soda lime and Baralyme. Methods. We measured the concentrations of compound A in four different brands of CO2 absorbent using a low-flow (1 l·min−1 fresh gas) model circuit in which 2% sevoflurane was circulated. Sodasorb II, Baralyme, Sofnolime and Wakolime-A were used as CO2 absorbents. The concentration of compound A was measured hourly, and the temperature of the CO2 absorbent was monitored. Results. The maximum concentration of compound A in the circuit was highest for Baralyme (25.5 ± 0.6 ppm) (mean ± SD), followed by Sodasorb II (18.9 ± 1.6 ppm), Wakolime-A (16.1 ± 0.7 ppm), and Sofnolime (15.8 ± 1.4 ppm). The maximum temperature was 50.8 ± 1.3°C for Baralyme, 48.8 ± 1.3°C for Wakolime-A, 47.0 ± 1.4°C for Sodasorb II, and 43.5 ± 3.9°C for Sofnolime. Conclusion. The relative concentrations of compound A in the low-flow circuit were Baralyme > Sodasorb II > Wakolime-A = Sofnolime. Received: August 27, 1999 / Accepted: January 13, 2000  相似文献   
10.
The present study assessed effects of estrogens and their steroid metabolites on the endometrial carcinogenesis in young adult mice initiated with N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG). A total of 272 female CD-1 (ICR) mice were used and equally divided into 17 groups. Mice were implanted cholesterol pellets to the back subcutis at 9 weeks of age. Pellets contained nothing (control) or one of the experimental agents, three different estrogens and their 13 different steroid metabolites, at a concentration of 0.5% (w/w). At 10 weeks of age, mice were given a single intra-uterine administration of ENNG at a dose of 25 mg/kg body weight. When reaching the 30 weeks of age (20 weeks after the ENNG treatment), mice were sacrificed to assess the development of endometrial proliferative lesions. While endometrial proliferative lesions, including hyperplasias and adenocarcinomas, were observed in all groups, the incidences of hyperplasias in the groups treated with 2-hydroxyestriol, 2-methoxyestradiol, 2-methoxyestriol and 16-epiestriol were significantly higher than that in the control group. On the other hand, adenocarcinomas were significantly developed in the groups treated with estrone, estradiol, estriol, 16beta-hydroxyestrone, 16alpha-hydroxyestrone and 17-epiestriol. These results indicate that, on the endometrial carcinogenesis in mice initiated with ENNG, estrogens and their metabolites belonging to the 16alpha-hydroxylation pathway and the upstream of the 16beta-hydroxylation pathway exert both promoting and progressing effects, whereas, the estrogen metabolites belonging to the 2- and 4-hydroxylation pathways (catechol estrogens) and the downstream of the 16beta-hydroxylation pathway exert only promoting or no effects. It is thus suggested that a metabolic profile of estrogens may be crucial for the endometrial carcinogenesis and that the rate of the 16alpha-hydroxylation may be associated with the increased carcinogenic risks of estrogens on the endometrium.  相似文献   
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