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11.
Analogs of opioid pentapeptide [D-Ala2, Leu5]enkephalin were prepared using two kinds of N-methylation reactions, namely quaternization and amide-methylation. Quaternization reaction with CH3I-KHCO3 in methanol was applied to the deprotected N-terminal group of the pentapeptide derivatives affording trimethylammonium group-containing analogs. [Me3+ Tyr1,D-Ala2, Leu5]enkephalin and its amide were found to show opioid activity on guinea pig ileium assay only slightly lower than the parent unmethylated peptides. Application of amide-methylation reaction using CH3I-Ag2O in DMF to the protected pentapeptide yielded a pentamethyl derivative in which all of the five N atoms were methylated. Deprotection of the derivative gave pentamethyl analogs of [D-Ala2, Leu5]enkephalin, which showed no significant activity on the guinea pig ileum assay and opiate-receptor binding assay.  相似文献   
12.
Abstract Although the vast majority of hepatitis B surface antigen (HBsAg) carriers of the world inhabit South-east Asia, very little is known about delta infection in this area. Therefore, a serological and immunohistological study was made in the Tokyo-Chiba area. One of 58 (1.7%) HBsAg carriers had anti-delta antibody in a high titre in serum. Delta antigen was immuno-histologically localized in the liver in two of 146 (1.4%) HBsAg carriers studied. The antigen was strongly stained in the nuclei, and positive cells were diffusely scattered throughout the liver in both cases. Neither subject was an illicit drug user: one had travelled to Italy 10 years earlier and the other had a blood transfusion during a 5-year residence in Bangkok in the past.
Thus, there is delta infection among non-intravenous drug users in Japan. Delta infection has been linked to severe liver damage, occasionally fatal. Once introduced, it could become epidemic in a country where hepatitis B virus infection is endemic, and might spread among non-drug users.  相似文献   
13.
Our objective was to determint; the adequate pacing rate during exercise in ventricular pacing by measuring exercise capacity, cardiac output, and sinus node activity. Eighteen patients with complete AV block and an implanted pacemaker underwent cardiopulmonary exercise tests under three randomized pacing rates: fixed rate pacing (VVJ) at 60 beats/min and ventricular rate-responsive pacing (VVIR) programmed to attain a heart rate of about 110 beats/min ar 130 beats/min (VVIR 110 and VVIR 130, respectively) at the end of exercise. Compared with VVI and VVIR 130, VVIR 110 was associated with an increased peak oxygen uptake(VVIR 110:20.3 ± 4.5 vs VVI: 16.9 ± 3.1; P < 0.01; and VVIR 130: 19.0 ± 4.1 mL/min per kg, respectively; P < 0.05) and a higher oxygen uptake at anaerobic threshold (15.3 ± 2.7, 12.7 ± 1.9; P < 0.01, and 14.6 ± 2.6 mL/min per kg; P < 0.05). The atrial rate during exercise expressed as a percentage of the expected maximal heart rate was lower in VVIR 110 than in VVI or VVIR 130 (VVIR 110: 75.9%± 14.6% vs VVI: 90.6%± 12.8%; P < 0.01; VVIR 110 vs VVIR 130: 89.1%± 23.1%; P < 0.05). There was no significant difference in cardiac output at peak exercise between VVIR 110 and VVIR 130. We conclude that a pacing rate for submaximal exercise of 110 beats/min may be preferable to that of 130 beats/min in respect to exercise capacity and sympathetic nerve activity.  相似文献   
14.
KAWASAKI, T., et al. : Determinant of QT Dispersion in Patients with Hypertrophic Cardiomyopathy. QT dispersion is thought to reflect a regional difference in repolarization process although QT interval is composed of depolarization and repolarization. This study was designed to investigate the effect of depolarization and repolarization on QT dispersion in hypertrophic cardiomyopathy. Standard 12-lead ECG was recorded in 70 hypertrophic cardiomyopathy patients with anteroseptal wall hypertrophy (HC-As), 8 patients with lateral wall hypertrophy (HC-L), 8 patients with diffuse hypertrophy (HC-D), and 46 normal controls. QRS, JTc, maximum and minimum QTc, and QTc dispersion were compared. The maximum QTc was greater in HC-As and HC-L than in the control; the minimum QTc was similar in all 3 groups; consequently, QTc dispersion was greater in HC-As and HC-L. In HC-D, the maximum QTc and the minimum QTc were greater than the control, which produced QTc dispersion similar to that in the control. JTc did not differ among 4 groups. In hypertrophic cardiomyopathy, both QTc and QRS duration were increased in the leads coinciding with the left ventricular portion of localized hypertrophy. We conclude that QTc dispersion depended on the heterogeneity of QRS duration or depolarization rather than repolarization, which in fact may be ascribed to the regionally different hypertrophy of the left ventricle in hypertrophic cardiomyopathy. (PACE 2003; 26[Pt. I]:819–826)  相似文献   
15.
16.
Sleep disorder in children with autism   总被引:1,自引:0,他引:1  
Abstract Eighty-eight children with autism, living in a suburb of Tokyo, were examined by questionnaire from 21 July to 31 August. Experienced sleep disorders were observed in 56 children; 44 of whom had sleep disorders before 3 years old. The average age when sleep disorders were seen to have stopped was 5 years old. The most common problem was difficulty falling sleep ( n = 23), followed by frequent awakening during sleep time ( n = 19), then early morning awakening ( n = 11). Bed-wetting was observed in 22 children.  相似文献   
17.
BACKGROUND: The effects of preoperative androgen deprivation on the outcomes of prostate cancer patients who received radical prostatectomy and subsequent adjuvant endocrine therapy have not yet been fully evaluated. METHODS: Patients with stage A(2), B or C prostate cancers were randomized to one of two groups: group I (n = 90), who received androgen deprivation (leuprolide and chlormadinone acetate) for 3 months followed by radical prostatectomy and subsequent adjuvant endocrine therapy (leuprolide alone), and group II (n = 86), who underwent the surgery followed by 3-month androgen deprivation (leuprolide and chlormadinone acetate) and subsequent adjuvant endocrine therapy (leuprolide alone). The effects of preoperative androgen deprivation on survival, clinical relapse (serum prostate specific antigen, PSA, above the normal level, local recurrence, or distant metastases), and PSA relapse (PSA above the detectable level) were evaluated at 5 years or later after treatment. RESULTS: There were no significant differences in overall, cause-specific, clinical relapse-free, or PSA relapse-free survival rates between the two groups. In a subanalysis, no prostate cancer deaths or clinical relapses were noted in 29 patients with organ-confined disease (OCD: negativity of capsular invasion, seminal vesicle invasion, surgical margins or nodal involvement). The odds ratio for OCD depending on group assignment was 2.44 (95% confidence interval, CI 1.04-5.72), for group I, demonstrating a higher probability of having OCD. This ratio was increased to 4.00 (95% CI 1.06-15.16) if the analysis was conducted in a subpopulation with prostate specific antigen levels less than 35.6 ng/mL and with clinical stage B or C cancers. CONCLUSION: Preoperative androgen deprivation has no demonstrable benefit in 5-year outcomes for patients undergoing radical prostatectomy and adjuvant endocrine therapy. However, it did increase the probability of OCD, which was associated with no clinical relapse during the follow-up. A longer observation is needed to clarify the exact extent of the benefits in terms of survival.  相似文献   
18.
Diastolic mitral regurgitation has been observed in patients with DDD pacemakers when the atrioventricular (AV) delay was prolonged. However, diastolic mitral regurgitation associated with first-degree AV block has not been fully studied. We examined transmitral blood flow in 24 patients with first-degree AV block and normal cardiac function (ages 35.3 ± 17.4 years), and in nine patients with DDD pacemakers and normal cardiac function (ages 73.1 ± 8.1 years), using pulsed Doppler echocardiography. Diastolic mitral regurgitation was observed in 19 of 24 patients with first-degree AV block. Although PQ interval was shortened from 0.32 ± 0.06 to 0.20 ± 0.05 seconds (P < 0.01) after 1 mg atropine sulfate IV, the interval between P wave (ECG) and the beginning of diastolic mitral regurgitation did not change, while the duration of diastolic mitral regurgitation was shortened from 0.15 ± 0.03 to 0.05 ± 0.03 seconds (P < 0.01). There was a significant correlation between changes in PQ interval and changes in the duration of diastolic mitral regurgifation (r = 0.92, P < 0.001). Although cardiac output (3.9 ± 0.05 L/min) and pulmonary capillary wedge pressure (5.1 ± 1.5 mmHg) were normal in all patients with pacemakers, diastolic mitral regurgitation was observed when the AV delay was prolonged. The critical PQ interval for the appearance of diastolic mitral regurgitation was 0.23 ± 0.01 seconds. In patients with prolonged PQ intervals, delayed ventricular contraction following atrial contraction may be associated with mitral regurgitation in the presence of a reversed AV pressure gradient. The results of this study suggest that diastolic mitral regurgitation occurs not only in patients with DDD pacemakers, but also with AAIR pacemakers when the PQ interval is prolonged. The occurrence of diastolic mitral regurgitation is associated with the pacing mode or the setting of AV delay.  相似文献   
19.
The purpose of this study was to evaluate heart rate variability (HRV) in patients with familial amyloid polyneuropathy (FAP) using the time- and frequency-domain analysis. The study population consisted of 19 patients with FAP, and 19 age and sex matched normal volunteers. The 24-hour Holter recordings of all subjects in sinus rhythm and off medication were analyzed. Five time-domain indices of HRV were computed. The frequency component of HRV was calculated by fast Fourier transform analysis of the RR intervals. The power spectrum of the low frequency (LF) between 0.04–0.15 Hz and high frequency (HF) between 0.15–0.40 Hz and the LF/HF ratio was calculated. Global measures of HRV including the standard deviation of the mean of RR intervals (SDNN) and the standard deviation of 5-minute mean RR intervals (SDANN) were decreased in patients with FAP. Specific vagal influences on HRV including the proportion of RR intervals more than 50 milliseconds different (pNN50) and the HF power on spectral analysis were less in patients with FAP. LF power and LF/HF ratio were more decreased in patients with FAP at the advanced stage than at the early stage. In conclusion, HRV was significantly decreased in patients with FAP at the early stage, and sympathetic activity was more decreased in patients at the advanced stage. These findings suggest that the decrease of the HRV is an indicator of this disease and the power spectral analysis of the HRV is beneficial in assessing the severity of the autonomic dysfunction.  相似文献   
20.
Percutaneous ethanol injection (PEI) was applied to 120 lesions in 95 patients with hepatocellular carcinomas (HCC) smaller than 3 cm in the past 6 years. All main target tumours, in 67 patients who had been followed by sonography for more than 6 months after PEI, decreased in size; 28 tumours (41.8%) became undetectable and have remained so until now. The 1-, 2-, 3-, 4- and 5-year survival rates calculated by the Kaplan-Meier method were 93%, 81%, 65%, 52% and 28% respectively. These survival rates were better than those of patients with HCC smaller than 3 cm who did not receive anticancer treatment (P less than 0.01). The survival of patients of the Child's A or Child's B status was better than that of those with Child's C disease. Recurrence occurred in areas within the liver different from the original lesion in 34% in one year, 61% in two years and 66% in three years after PEI. PEI was then repeated in 61% of such patients.  相似文献   
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