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931.
In 261 infants with vomiting, 11 duodenal abnormalities were diagnosed with fluid-aided ultrasound (US). These abnormalities included duodenal obstruction, malrotation with and without associated volvulus, incomplete rotation, and duodenal stenosis. US was the initial modality used in the evaluation of vomiting in these neonates and young infants. The overall sensitivity and specificity of fluid-aided US evaluation of duodenal abnormalities were 100% and 99%, respectively. (Workup bias limits the reliability of these figures.) Fluid-aided US examination of the stomach and duodenum provided a dynamic view of duodenal rotation and anatomy, and at the very least provided a method of triaging those infants who may require surgery, upper gastrointestinal series, or follow-up US to make a definitive diagnosis.  相似文献   
932.
933.

Background  

Oral health-related quality of life (OHRQoL) measures are being increasingly used to introduce dimensions excluded by normative measures. Consequently, there is a need for an index which evaluates children's OHRQoL validated for Brazilian population, useful for oral health needs assessments and for the evaluation of oral health programs, services and technologies. The aim of this study was to do a cross-cultural adaptation of the Child Oral Impacts on Daily Performances (Child-OIDP) index, and assess its reliability and validity for application among Brazilian children between the ages of eleven and fourteen.  相似文献   
934.
Previous experiments with rifalazil (RLZ) (also known as KRM-1648) in combination with isoniazid (INH) demonstrated its potential for short-course treatment of Mycobacterium tuberculosis infection. In this study we investigated the minimum RLZ-INH treatment time required to eradicate M. tuberculosis in a murine model. RLZ-INH treatment for 6 weeks or longer led to a nonculturable state. Groups of mice treated in parallel were killed following an observation period to evaluate regrowth. RLZ-INH treatment for a minimum of 10 weeks was necessary to maintain a nonculturable state through the observation period. Pyrazinamide (PZA) was added to this regimen to determine whether the treatment duration could be further reduced. In this model, the addition of PZA did not shorten the duration of RLZ-INH treatment required to eradicate M. tuberculosis from mice. The addition of PZA reduced the number of mice in which regrowth occurred, although the reduction was not statistically significant.  相似文献   
935.
BACKGROUND: The objective was to evaluate the effect of patient characteristics and other factors on cardiopulmonary resuscitation (CPR) survival, hospital discharge survival and function, and long-term survival. METHODS: All patients 18 years and older experiencing in-hospital CPR from December 1983 through November 1991 at Marshfield Medical Center (Marshfield Clinic and adjoining St Joseph's Hospital), Marshfield, Wis, were selected. We performed a retrospective medical record review and augmented these data with updated vital status information. MAIN OUTCOME MEASURES: Cardiopulmonary resuscitation survival, hospital discharge survival and function, and long-term survival. RESULTS: Of 948 admissions during which CPR was performed, 61.2% of patients survived the arrest and 32.2% survived to hospital discharge. Mechanism of arrest was the most important variable associated with hospital discharge. Patients with pulseless electrical activity had the worst chance of hospital discharge, followed by those with asystole and bradycardia. Follow-up information was available for 298 patients who survived to discharge. One year after hospital discharge, 24.5% of patients, regardless of age, had died. Survival was 18.5% at 7 years in those 70 years or older, compared with 45.4% in those aged 18 to 69 years. Heart rhythm at the time of arrest strongly influenced long-term survival. Bradyarrhythmias produced a nearly 2-fold increased mortality risk compared with normal sinus rhythm. CONCLUSIONS: Survival until hospital discharge after CPR at our institution during an 8-year period was higher than previously reported for other institutions. Long-term survival after discharge was equal to or higher than reported estimates from other institutions. Hospital admission practices and selection of patients receiving CPR may account for these findings.  相似文献   
936.
937.
938.
This study aimed to validate prognostic models for predicting ongoing pregnancy after the first and second in-vitro fertilization cycles. Models were developed using data from the University Hospital, Nijmegen, 1991-1994 and tested using more recent data from the same centre and data from two other centres. Although the variables included in the models seemed plausible, the predictions of the models were unsatisfactory. The models did not discriminate between women who had achieved pregnancy and women who did not achieve pregnancy; neither could they indicate which women had a (very) low probability of ongoing pregnancy. Taking into account the success rate of a specific clinic or the success rate during a specific period did not show any advantage. The predictions were even inaccurate in the same hospital during another period. It is obvious that these prognostic models should not be used. This study shows the importance of validating prognostic models before their implementation in clinical practice.   相似文献   
939.
The genetic basis of myotonic dystrophy (DM) is the expansion of an unstable CTG repeat in the 34 UTR of the DM protein kinase gene on chromosome 19. One of the principal features of the DM mutation is an extraordinarily high level of somatic mosaicism, due to an extremely high degree of somatic instability both within and between different tissues. This instability appears to be biased towards further expansion and continuous throughout the life of an individual, features that could be associated with the progressive nature of the disease. Although increasing measured allele size between patients clearly correlates with an increased severity of symptoms and an earlier age of onset, this correlation is not precise and measured allele length cannot be used as an accurate predictor of age of onset. In order to further characterize the dynamics of DM CTG repeat somatic instability, we have studied repeat length changes over time in 111 myotonic dystrophy patients with varying clinical severity and CTG repeat size over time intervals of 1-7 years. We have found a direct progression of the size heterogeneity over time related to initial CTG repeat size and the time interval and always biased towards further expansion. Attempts to mathematically model the dynamics have proved only partially successful suggesting that individual specific genetic and/or environmental factors also play a role in somatic mosaicism.   相似文献   
940.
Low level chromosome mosaicism found at amniocentesis is problematic for clinicians and patients. We report prenatal diagnosis of a fetus with a rare karyotype of 47.XX, + 15/46, XX. Second trimester amniocentesis was performed for advanced maternal age. Fetal ultrasound revealed a hypoplastic right ventricle and intrauterine growth retardation (IUGR). The rest of the fetal anatomy was within normal limits. A mosaic karyotype of 47.XX, + 15/46, XX was observed. The couple interrupted the pregnancy at 19 weeks by dilation and suction evacuation. Careful evaluation of multiple pieces of fetal parts and placenta revealed one abnormal finding: a single umbilical artery. Cytogenetic metaphase and fluorescent in situ hybridization (FISH) interphase analyses of cells from fetal lung, heart, placenta, and skin revealed the presence of the trisomic line in all tissues. Molecular analysis demonstrated that the origin of the extra chromosome 15 was maternal, the error most likely occurred in meiosis I and the diploid line was of biparental inheritance. This case report discusses the associated findings in this fetus and reviews the literature describing other cases of mosaic trisomy 15.  相似文献   
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