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1.
In a survey of clinical trials concerning the efficacy of short-contact therapy with anthralin in psoriasis vulgaris, focusing principally on methodologic issues, twenty-four papers published between January 1982 and December 1989, in English, French, and Italian, were selected. Nine of 24 papers reported on more than one trial, giving a total of 37 clinical trials to be evaluated. A great heterogeneity was evident in many aspects of the design and conduct of these trials, making pooling of results impossible. Most trials suffered from flaws in general methodologic aspects such as randomization and blinding. Limitations in general applicability of results were discussed with reference to the popular use of self-control design and selection of composite indexes (e.g., PASI) as an outcome variable. Published trials are not a reliable guide to clinical decisions concerning short-contact therapy, and some methodologic observations we made could be of general interest in designing clinical trials of psoriasis.  相似文献   
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The aim of the present study is to evaluate drawbacks and advantagesof the choice of hospital versus population controls in a casecontrol study on diet and cancer through the analysis of a retrospectivestudy on diet and gastric cancer (GC) conducted in Forli, Italy,involving 232 cases, 430 population controls and 252 hospitalizedcontrols. The present paper reports the comparison of resultson diet and GC risk obtained using the 2 types of controls.Population controls tended, in general, to eat all kinds offoods slightly more frequently (bread, pasta, cold cuts, freshfish, seasoned cheeses, legumes, garlic, onions and preservedfruits), with the exception of cooked vegetables, which werereported less frequently by population than by hospital controls.ORs for specific foods adjusted for confounders and other foodswere consistent in the separate models including populationand hospital controls respectively for all food groups, withthe exception of cooked vegetables which represented a protectivefactor only when hospital controls were considered (high consumers,population controls: adjusted, OR=0.9, trend p value 0.54; highconsumers, hospital controls, adjusted OR=0.5, trend p value<0.01). Hospital controls were slightly less often currentsmokers (22.6 versus 30.0%) and more often regular wine drinkers(57.5 versus 47.8%) compared with population controls, but noneof these variables was associated with GC risk. The main resultsin this study were consistent using both types of controls,nevertheless the distribution of some dietary variables notrelated to the disease under study differed between the 2 controlgroups, suggesting some caution in the use of hospital controlswhen studying diseases other than GC.  相似文献   
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In the diagnostic work‐up of hypersomnias of central origin, the complaint of excessive daytime sleepiness should be objectively confirmed by MSLT findings. Indeed, the features and diagnostic utility of spontaneous daytime sleep at 24 h continuous polysomnography (PSG) have never been investigated. We compared daytime PSG features to MSLT data in 98 consecutive patients presenting with excessive daytime sleepiness and with a final diagnosis of narcolepsy with cataplexy/hypocretin deficiency (n = 39), narcolepsy without cataplexy (n = 7), idiopathic hypersomnia without long sleep time (n = 19), and ‘hypersomnia’ with normal sleep latency at MSLT (n = 33). Daytime sleep time was significantly higher in narcolepsy‐cataplexy but similar in the other groups. Receiver operating characteristics (ROC) curves showed that the number of naps during daytime PSG predicted a mean sleep latency ≤8 min at MSLT with an area under the curve of 0.67 ± 0.05 (P = 0.005). The number of daytime sleep‐onset REM periods (SOREMPs) in spontaneous naps strikingly predicted the scheduled occurrence of two or more SOREMPs at MSLT, with an area under the ROC curve of 0.93 ± 0.03 (P < 10?12). One spontaneous SOREMP during daytime had a sensitivity of 96% with specificity of 74%, whereas two SOREMPs had a sensitivity of 75%, with a specificity of 95% for a pathological REM sleep propensity at MSLT. The features of spontaneous daytime sleep well correlated with MSLT findings. Notably, the occurrence of multiple spontaneous SOREMPs during daytime clearly identified patients with narcolepsy, as well as during the MSLT.  相似文献   
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Summary. Between 1970 and 1976, 290 patients with endometrial cancer were treated at the 1st Obstetrics and Gynecology Clinic of the University of Milan. The median age was 62 years. Surgery was completed in 262 (90.3%) patients. Abdominal hysterectomy was used in 158 (70.9%) stage I and 40 (71.4%) stage II/III patients; vaginal hysterectomy in 55 (24.7%) stage I and nine (16.1%) stage II/III patients. Resection of the upper vagina was performed in 168 patients. Postoperative external beam radiotherapy was used in stage II/III patients and in 44 (19.7%) stage I high-risk patients. Ten-year survival, determined by the life-table method, was 84.8% in stage I (223 patients), 53.4% in stage II (37 patients), 64.4% in stage III (19 patients), and 9.1% in stage IV (11 patients). Factors associated with poorer prognosis were: late age at diagnosis (P<0.001); deep myometrial invasion (P<0.001); poorly differentiated histological grade ( P =0.11); lack of resection of the upper vagina ( P = 0.13). The role and importance of surgery is discussed, with special emphasis on the selective use of the vaginal route in aged, obese and medically high-risk patients.  相似文献   
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Abstract:  Approximately, 1–4% of all new melanoma cases occur in patients younger than 20 years. The clinical presentation of melanoma in the young is often challenging. We report the experience of the Melanoma Unit of University Hospital Spedali Civili of Brescia, Italy. Study subjects were drawn from 1470 patients with histologically confirmed melanoma. From this group, melanoma developed in 12 patients younger than 19 years. For each melanoma diagnosed, histologic characteristics, treatment, and outcomes were evaluated. Of the 12 patients described in this study, four were men and eight were women. The average age was 15.6 years ranging from 11 to 18 years. Regarding invasive melanomas, Breslow thickness ranged from 0.15 to 0.66 mm with a mean thickness of 0.36 mm. Primary treatment of 12 patients included wide local excision of their primary lesions. In many cases reported in literature lesions are amelanotic, nodular, and resemble pyogenic granuloma. From our case studies it was found that the clinical characteristics detected in melanomas diagnosed in childhood and adolescence have been the same as those described in adults and that the ABCDE clinical criteria may be helpful basics of melanoma.  相似文献   
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Twenty-three multiprogrammable pacemakers and four implantable cardioverter defibrillators (ICDs) containing either complementary metal-oxide semiconductor (CMOS) or CMOS/Bipolar integrated circuit (IC) technology were exposed to 6-MV photon and 18-MeV electron radiation at various dose levels. Of the 17 pacemakers exposed to photon radiation eight failed before 50 Gy, whereas four of the six pacemakers exposed to electron radiation failed before 70 Gy. Photon scatter doses were well tolerated. For the ICDs detection and charging time increased with accumulated radiation dose, the charging time increased catastrophically at less than 50 total pulses delivered when compared with the charging time of six implanted ICDs. Sensitivity and output energy delivered by the ICD pulse were constant during the test. It was found that devices using the shorter channel length IC technology (i.e., 3 microns CMOS) were per se harder to ionizing radiation than the devices using larger channel length IC technologies (i.e., either 8 microns CMOS or combined 5 microM CMOS/20 V Bipolar). In fact, none of the devices based on 3 microns CMOS IC technology failed before 76 Gy, which is above the highest dose level (70 Gy) normally used in radiation oncology treatments.  相似文献   
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PLADYS, P., et al. : Influence of Sympathetic Heart Rate Modulation on R Interval Rate Adaptation In Conscious Dogs . The objective was to test if changes in autonomic tone still influenced the RT-RR relationship when full RT adaptation is completed, when heart rate is controlled, and when beat-to-beat variability is abolished by atrial pacing. Eight dogs (8–11 kg) were chronically instrumented with atrial pacing electrodes. Digital ECG (1,000 Hz, 12 bits) were recorded from healthy conscious dogs during spontaneous sinus rhythm and during atrial pacing. The protocol was repeated before and after atenolol (2 mg/kg), prazosin (0.5 mg/kg), or atenolol + prazosin. A vocal incitation was used as sympathetic stimulation. Beat-to-beat quantitative analysis of the RT interval (from QRS apex to end of T wave) was correlated with the preceding RR by linear regression. In spontaneous rhythm, atenolol increased RR (P < 0.001), RT (P < 0.001), and short-term heart rate variability (P < 0.01) and decreased RT-RR slopes (P < 0.001). Prazosin did not significantly modify any parameter. Sympathetic stimulation decreased RR (P < 0.001), RT (P < 0.05), and short-term heart rate variability (P < 0.01) and increased RT-RR slopes (P < 0.001). In atrial pacing, the RTRR slopes were steeper during pacing than during spontaneous rhythm but were not modified by pharmacological manipulation of the autonomic nervous system. During sinus rhythm the RT-RR relationship is increased by sympathetic stimulation and decreased by β–blockade. When heart rate modulation and the effects of the time delay in RT rate adaptation are abolished by atrial pacing, the influence of autonomic tone on RT rate adaptation disappears.  相似文献   
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