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81.
82.
近存活期分娩(PVB)儿各组织系统发育极不成熟,易发生各种器官功能损害和并发症,预后常不佳。目前关于PVB儿出生后早期管理的报道不多,诸多尚待解决的问题仍是围产医学所面临的挑战。经有效的新生儿复苏和呼吸循环支持、积极的营养支持和喂养、防治感染、内分泌和代谢性疾病管理、积极处理早产儿相关并发症,以及发育支持护理、家庭参与式护理等一系列个体化管理和精细化护理,四川省医学科学院·四川省人民医院成功救治了1例胎龄23周,出生体质量(BW)为450 g的PVB儿。本文通过总结1例PVB儿的出生后早期管理,并结合文献复习进行归纳总结,以期为提高BW<500 g的PVB儿存活率并获得良好预后提供经验及借鉴。  相似文献   
83.
Background: Tyrosine hydroxylase (TH) is a specific marker for catecholaminergic neurones. Some reports have demonstrated a decrease of TH in the sudden infant death syndrome (SIDS) compared with controls. To further investigate this, the correlation between TH and sleep apnea was investigated here. Materials and methods: Among 27,000 infants studied prospectively to characterize their sleep–wake behavior, 38 infants died under 6 months of age. They included 26 cases of SIDS. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and the duration of sleep apnea were analyzed. The brain-stem material was collected and subjected to immunohistochemical studies for TH. The density of TH-immunoreactive neurons was measured in the nucleus hypoglossus, nervus vagus dorsalis, solitary and ambiguus and the ventrolateral medulla (VLM) in the medulla oblongata. Correlation analyses were carried out between the density of TH-immunoreactive neurons and the data from the sleep apnea studies. Results: There was no SIDS specific correlation between TH-immunoreactive neurons in the nucleus hypoglossus, nervus vagus dorsalis, solitary and ambiguus and the ventrolateral medulla in the medulla oblongata and the frequency and duration of sleep apnea. Conclusions: No significant association between the pathological data and the physiological data refers to TH-positive neurons in the medulla oblongata in SIDS victims.  相似文献   
84.
Background: The Ki-67 antigen appears in all human proliferating cells during late G1, S, M and G2 phases of the cell cycle, but is consistently absent in the Go phase (noncycling) cells. The correlation between Ki-67 in the brainstem and sleep apnea in victims of the sudden infant death syndrome (SIDS) was investigated to elucidate cell kinetics in the brainstem of this condition, which is still the main cause of postneonatal infant death. Materials and methods: Twenty-six cases of SIDS occurred among 38 infants dying under 6 months of age in a cohort of 27,000 infants studied prospectively to characterize their sleep–wake behavior. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and duration of sleep apnea were analyzed. At autopsy, brainstem material was collected and immunohistochemistry for Ki-67 was carried out. The density of Ki-67-positive neurons was measured semiquantitatively. Correlation analyses were carried out between the density of Ki-67-positive neurons and the data on sleep apnea. Results: Except in two cases in SIDS victims and in one control, the detection of Ki-67 was negative. No correlation analysis between the Ki-67 and of sleep apnea was found. Conclusions: There were no abnormal cell kinetics detected by the demonstration of Ki-67 antigen in the brainstems of SIDS victims.  相似文献   
85.
Objectives: The investigation of the effect of time and type of menopause on bone mineral density (BMD) at different ages. Methods: Five hundred and fourteen women, who had never received any hormonal substitution were studied in a cross-sectional design: 177 with normal (NMP), 210 with surgical (SUMP) and 127 with premature natural (EMP) menopause. Age at menopause was 49.1±3.9, 38.3±4.7 and 38.1±4.2 years (mean±1 S.D.), respectively. BMD was measured at L2–L4 vertebrae and proximal femur by the DEXA method. Results: EMP women presented significantly lower vertebral BMD than NMP women in the 45–55-years segments (P<0.001), but did not differ from SUMP women. This group exhibited lower vertebral BMD than NMP between 45 and 50 years (P<0.001). Regarding femoral neck, EMP women exhibited lower values than SUMP in the 45–50 and 55–65 age segments (P<0.001) whereas SUMP women presented significantly higher BMD values than NMP women after 55 years of age (P<0.001). The percentages of women with vertebral BMD (T-score values) in the osteoporotic range were significantly greater in EMP compared with either NMP or SUMP groups (both P<0.001) whereas in femoral neck lower in SUMP than the other two categories. Conclusions: Women with either natural or surgical premature menopause exhibit lower BMD of trabecular bone compared with normal menopause women at the age segments 45–55 and 45–50, respectively. However, surgical menopause women exceed normal menopause women in their mixed bone BMD values after 60 years as well as premature natural menopause women at almost all age segments.  相似文献   
86.
Attention mediates the acquisition and encoding of information about the world and is central to motor action. Heart rate deceleration and behavioral inhibition are sensitive indices of the attentional process, but it is unknown whether these indices are valid in the context of overt action. The current study investigated the relationship between visual attention, action, and heart rate during reaching in 7(1/2)-month-old infants. We found that infants showed prolonged looking and large heart rate decelerations on reaching and looking trials. We conclude that overt action itself does not prevent the autonomic and behavioral changes that are also seen in attention to simple visual displays and that attention is maintained throughout the act of reaching.  相似文献   
87.
双歧杆菌对早产儿食道pH值的影响及临床意义   总被引:2,自引:0,他引:2  
目的为探讨双歧杆菌对早产儿食道pH值的影响,及其对早产儿易发生的消化道疾病的防治意义。方法我们采用便携式24hpH值自动记录仪,对61例早产儿进行了食道pH值的动态监测。结果口服双歧杆菌活菌制剂组的30例早产儿,食道pH值明显高于未服药的对照组,t=2.4093,P<0.05。总pH值<4的时间占总观察时间的百分比显著小于对照组。并且治疗组发生消化道疾患的人数也较对照组少。结论早产儿口服双歧杆菌活菌制剂可以减少胃食道反流等消化道疾病的发生。  相似文献   
88.
目的探讨我院2006年334例早产儿,分析发生的危险因素,以总结提高产科早产预防、医疗水平,并提供研究参考。方法早产组334例与同期分娩的足月对照组334例分析比较,早产的临床相关因素及对围产儿的影响。结果胎膜早破,妊娠高血压综合征,前置胎盘,臀位,多胎妊娠是早产的重要因素。早产使新生儿窒息,围生儿死亡,低体重儿增加。结论早产使围产儿窒息和死亡率增加。加强早产预测可望降低早产的发生,提高围生医学质量。  相似文献   
89.
Breast development gives insights into breast disease   总被引:2,自引:0,他引:2  
Aims : Studies of developing human breasts are essential for understanding the organogenesis as well as molecular pathogenesis of benign and malignant breast diseases. In this study we have examined the distribution of TGF-α, TGF-β1, tenascin-C and collagen type IV with the aim of starting to build a picture of the profile of molecules that may be involved in the development of the human breast.  

Methods and results


Ten fetal breasts (16 to 23 weeks of gestation) and 45 infant breasts, ranging in age from newborn to 2 years, were used in this study. Paraffin sections from these samples were immunostained with antibodies for these proteins and for Ki67 to elucidate the level of proliferative activity in different stages of breast development. TGF-α immunoreactivity was observed both in the stromal and the epithelial cells within fetal and infant breasts up to 25 days. TGF-β1 immunoreactivity was localized in the extracellular matrix. Tenascin-C was found around the neck of the developing breast bud and in the extracellular matrix of the infant with peaks in the newborn at 6–12 weeks. The immunoreactivity for type IV collagen was more intense in the region of the breast bud neck in the fetal breasts and reduced around the tips of lobular and terminal-end buds within the infant breasts.  

Conclusions


The distribution of the growth factors and extracellular matrix proteins within the developing human breast indicates that they play a significant role in different cellular compartments during morphogenesis and provides insights into breast disease.  相似文献   
90.
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