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41.
The autonomic nervous control of cardiac function during active orthostatic load has been studied by measuring the power spectrum of heart rate fluctuations in 16 insulin-dependent diabetic patients and 14 age-matched control subjects. The patients were subdivided into two groups: 8 with normal respiratory sinus dysrhythmia (RSA+) and 8 with reduced respiratory sinus dysrhythmia (RSA-). In RSA- patients the total power (0.01-0.50 Hz) was significantly reduced compared with control subjects (4.7 versus 15.5 min-2, 2p less than 0.05) and the pattern of heart rate fluctuations was characterized by a relative increase in the low-frequency component (0.01-0.05 Hz) as compared with RSA+ patients and control subjects (45% versus 24% and 27%, both 2p less than 0.01). There was also a significant reduction in the high-frequency component (0.15-0.50 Hz) as compared with RSA+ patients and control subjects (17% versus 36% and 33%, both 2p less than 0.05). During standing, a significant increase in total power was found only in control subjects (2p less than 0.01) and the difference between control subjects, and RSA+ and RSA- patients reached significance (32.2 versus 15.1 and 12.7 min-2, 2p less than 0.02 and 2p less than 0.01). The pattern of heart rate fluctuations in RSA- patients showed no significant change on standing. These results suggest that the reduced overall heart rate variability in diabetic patients with cardiac autonomic neuropathy is associated with a typical heart rate fluctuation pattern.  相似文献   
42.
选择89年2月至90年2月175例上呼吸道感染患儿,分为病毒唑雾化吸入组(61例).病毒唑全身给药组(53例)和对照组(61例).平均退热时间分别为30.01±.11,31.89±9.28,40.57±16.94小时.病毒唑组与对照组有非常显著性差异(p<0.01)但两病毒唑治疗组之间无显著性差异,并发现发病时间在一天内接受治疗者,退热时间明显短于超过一天之病例,且发病两天后治疗者与对照组已无显著差异(p<0.05).病毒唑全身用药组和对照组共有4例发展为支气管炎和肺炎,而雾化吸入组无,说明该治疗方法可以阻止病毒感染蔓延至下呼吸道.  相似文献   
43.
Vesicovaginal fistulas (VVFs) occurring as a result of obstetric trauma are a vast problem in Nigeria and Ghana, where at least 20 000 women await repair, and fewer than 50 physicians have the necessary expertise. Through a series of conferences those VVFs that are at high risk and those at low-risk for repair failure, were identified. A clinic was established where repair of low-risk VVFs was done on an ongoing basis in a remote region of Ghana. A visiting surgical team was utilized to repair the difficult, or high-risk, VVFs, which included 4–6 cm VVFs (3), recurrent VVF (1), combined VVF and RVF (rectovaginal fistula), a large 5 cm juxtacervical VVF (1), and a vesicouterine fistula (1). Management of these patients and others with VVF repair complications is discussed.  相似文献   
44.
Seven middle-aged men with manifest type II diabetes mellitus underwent an endurance training programme for 10–15 weeks. The maximal aerobic capacity, as well as the endurance capacity, was improved by 10% (p<0.05). The intramuscular glycogen store increased by more than 80% (p<0.05) from 350 μmol/g dw (dry weight), and the activities of citrate synthase and 3-hydroxy-acyl-CoA dehydrogenase increased by more than 50% (p<0.05) and 30% (p<0.05). The activity of glycogen synthase was decreased by approximately 20% (p<0.05), whereas lactate dehydrogenase remained unchanged. Capillaries/fibre and fibre area increased by more than 50% (p<0.05) and 30% (p<0.05) leaving the area of supply constant. Training did not influence fasting blood lipids and glucose, glycosylated hemoglobin, oral glucose tolerance, and insulin response to an oral glucose load measured 72 hours post-exercise. It is concluded that patients with manifest type II diabetes, as normoglycaemic individuals, adapt to physical training. However, no persistent effect on glucohomeostasis and lipaemia is produced by short-term training in the diabetic patients.  相似文献   
45.
A feedforward network is used to recognize short, digitized, isolated utterances. A high, multispeaker recognition rate is achieved with a small vocabulary with a single training utterance. This approach makes use of the pattern recognition property of the network architecture to classify different temporal patterns in the multidimensional feature space. The network recognizes the utterances without the need of segmentation, phoneme identification, or time alignment. We train the network with four words spoken by one single speaker. The network is then able to recognize 20 tokens spoken by 5 other speakers. We repeat the above training and testing procedure using a different speaker's utterances for training each time. The overall accuracy is 97.5%. We compare this approach to the traditional dynamic programming (DP) approach, and find that DP with slope constraints of 0 and 1 achieve 98.5% and 85% accuracies respectively. Finally we validate out statistics by training and testing the network of a four-word subset of the Texas Instruments (Tl) isolated word database. The accuracy with this vocabulary exceeds 96%. By doubling the size of the training set, the accuracy is raised to 98%. Using a suitable threshold, we are able to raise the accuracy of one network from 87% to 98.5%. Thresholding applied to all networks would then raise the overall accuracy to well over 99%.

This technique is especially promising because of the low overhead and computational requirements, which make it suitable for a low cost, portable, command recognition type of application.  相似文献   

46.
目的研究支气管哮喘(简称哮喘)过敏性刺激诱发气道感觉神经敏化机制。方法成年雄性豚鼠39只,按随机数字表法分为生理盐水致敏/激发对照组(A组,9只)、卵白蛋白(OVA)致敏/生理盐水激发对照组(B组,9只)、OVA致敏/激发实验组(C组,21只)。A组以生理盐水(0.5ml/只)致敏,B、C组以10%OVA(0.5ml/只)致敏,第10天开始雾化吸入生理盐水(A、B组)或1%OVA(C组)进行激发,每天1次,每次30min,根据实验需要又将C组21只豚鼠分为激发1d组(C1组,6只)、连续激发3d组(C2组,6只)、连续激发5d组(C3组,9只)。利用免疫荧光双标技术结合激光共聚焦扫描显微观察与Westernblot技术,研究生长相关蛋白43(GAP43)在气道神经以及结状神经节、颈静脉神经节内分布与水平及与P物质(SP)和胶质源神经生长因子(GDNF)受体c RET表达神经元关系。结果免疫荧光结果显示,C3组豚鼠气道内GAP43免疫反应阳性神经呈网状分布于大、中支气管内,以黏膜下层为主,部分GAP43阳性神经纤维向黏膜层内延伸;在结状神经节和颈静脉神经节内有大量GAP43免疫阳性神经胞体,在结状神经节内主要与SP免疫阳性胞体共存,在颈静脉神经节内主要与c RET免疫阳性胞体共存。Westernblot结果显示,A、B、C1、C2、C3组GAP43蛋白表达水平吸光度(A)值分别为0.38±0.04、0.41±0.03、0.49±0.05、0.79±0.08、0.76±0.04。C1、C2、C3组分别与A、B组比较差异均有统计学意义(P均0.05);C2组GAP43蛋白表达与C1组比较差异有统计学意义(P<0.01),但与C3组GAP43蛋白表达比较差异无统计学意义(P>0.05)。结论哮喘过敏性刺激能诱发气道感觉神经———SP肽能神经、GDNF敏感性神经纤维与胞体表达GAP43蛋白。  相似文献   
47.
The Diploma in Clinical Dentistry (Conscious Sedation and Pain Control) of the Faculty of Dentistry, University of Sydney, is the first dedicated programme devoted to this field in Australia. Its development followed a decision by the Dental Board of New South Wales to require a formal qualification from the University of Sydney before dental practitioners could offer sedation and pain management in practice.
The programme is conducted at Westmead Hospital in conjunction with the Department of Anaesthetics, and satisfies the guidelines developed by the Royal Australasian College of Dental Surgeons and the Royal Australasian College of Surgeons.
The course is conducted either over one or two years, with block sessions requiring attendance at Westmead Hospital, together with assignments which are completed outside the block sessions. In this way, a dental practitioner enrolled in the programme is able to continue practice.
The block sessions need not be completed over one year, but must be completed within two years.  相似文献   
48.
49.
A new approach designed to establish the most suitable area for eccentric viewing and to teach and train patients with severe age-related macular degeneration (AMD) to use the eccentric viewing technique is described. Using a computer and video display based system, as well as software written specifically for this purpose, we investigated and trained ten consecutive patients with AMD. The patients were 80.1 ± 5.6 years old, on average. All of them had an absolute central scotoma. Mean visual acuity was 0.035 ± 0.016. After 30 min of testing, instruction and reading on the screen, followed by 2.6 ± 0.69 one-hour training sessions, on average, with the low vision therapist, reading newspaper and book texts with the aid of hyperoculars or aplanatic systems and a very short reading distance, the patients achieved a reading speed of 58.9 ± 19.7 words/min, significantly (p<0.001) higher than the initial speed when reading on the screen, 11.5 ± 4.5 words/min.  相似文献   
50.
Branhamella catarrhalis is being isolated with increasing frequency from patients with symptoms and signs of respiratory tract infection. Records of 77 patients were reviewed to define the spectrum of respiratory illness and to compare clinical and laboratory features with those of respiratory infection due to Haemophilus influenzae. Both B catarrhalis and H influenzae caused respiratory infection predominantly in elderly males with underlying heart or lung disease. There were no clinical or laboratory features aside from sputum Gram stain and culture which differentiated the two groups. Although fewer than one-half of each group received antibiotics, no patient developed progressive respiratory disease.  相似文献   
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