全文获取类型
收费全文 | 8590篇 |
免费 | 609篇 |
国内免费 | 89篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 295篇 |
妇产科学 | 291篇 |
基础医学 | 929篇 |
口腔科学 | 159篇 |
临床医学 | 928篇 |
内科学 | 1862篇 |
皮肤病学 | 215篇 |
神经病学 | 860篇 |
特种医学 | 227篇 |
外科学 | 1403篇 |
综合类 | 166篇 |
一般理论 | 3篇 |
预防医学 | 421篇 |
眼科学 | 136篇 |
药学 | 642篇 |
中国医学 | 70篇 |
肿瘤学 | 576篇 |
出版年
2023年 | 43篇 |
2022年 | 101篇 |
2021年 | 218篇 |
2020年 | 105篇 |
2019年 | 196篇 |
2018年 | 233篇 |
2017年 | 165篇 |
2016年 | 186篇 |
2015年 | 253篇 |
2014年 | 312篇 |
2013年 | 433篇 |
2012年 | 559篇 |
2011年 | 624篇 |
2010年 | 376篇 |
2009年 | 354篇 |
2008年 | 518篇 |
2007年 | 504篇 |
2006年 | 520篇 |
2005年 | 460篇 |
2004年 | 446篇 |
2003年 | 326篇 |
2002年 | 309篇 |
2001年 | 275篇 |
2000年 | 216篇 |
1999年 | 217篇 |
1998年 | 59篇 |
1997年 | 60篇 |
1996年 | 54篇 |
1995年 | 33篇 |
1994年 | 45篇 |
1993年 | 44篇 |
1992年 | 100篇 |
1991年 | 102篇 |
1990年 | 104篇 |
1989年 | 97篇 |
1988年 | 80篇 |
1987年 | 71篇 |
1986年 | 58篇 |
1985年 | 56篇 |
1984年 | 54篇 |
1983年 | 37篇 |
1982年 | 16篇 |
1981年 | 25篇 |
1980年 | 20篇 |
1979年 | 40篇 |
1978年 | 23篇 |
1977年 | 20篇 |
1976年 | 23篇 |
1975年 | 19篇 |
1974年 | 23篇 |
排序方式: 共有9288条查询结果,搜索用时 15 毫秒
21.
22.
The reversal of diastolic cerebral blood flow has been regarded as a characteristic waveform of brain death and a useful confirming sign. We report 2 patients who had diastolic flow reversal but survived. One, a 1-month-old boy with status epilepticus, had reversal of diastolic cerebral blood flow detected by Doppler ultrasound soon after admission. Reversal disappeared after medical management for increased intracranial pressure and seizure control. He recovered without sequelae. The other, a 6-month-old girl with choroid plexus papilloma, had reversal of diastolic flow during abrupt clinical deterioration. Emergent surgical removal of the tumor was performed and she survived with hemiparesis and psychomotor retardation. Our patients demonstrated that even in the presence of diastolic reversal of cerebral blood flow, prompt and effective treatment can avoid a fatal outcome. 相似文献
23.
24.
A W Chiu M T Chen W J Huang S T Young C Cheng S W Huang C L Chu L S Chang 《European urology》1992,22(3):250-254
Laparoscopic nephrectomy was performed in 15 male pigs, the procedure was successful in 14. Extraction of the intact kidney through a 5-cm lower abdomen incision was done in 7 animals; complete destruction and evacuation of the kidney was accomplished by a round-knife suction device through a 1-cm port in another 7 pigs. Grossly, the specimen consisted of sausage-like tubular renal tissue and a small amount of tissue debris. Pathology revealed that the glomerular and tubular structures were well preserved, no interstitial hematoma could be found. Four ports were usually used, one 1-cm umbilical camera port, one 0.5-cm port for ureter traction, and two 1-cm working ports along the midclavicular line. All the pigs recovered uneventfully. The average operation time was 3 h 20 min. The application of endo-GIA (United States Surgical Corporation) for renal hilum reduced the operative time to 2 h 20 min. Complications included renal vein tear during endoclip application and cutting in the first case, mild subcutaneous emphysema in 2 cases. This first pig received exploratory laparotomy for the repair and ligation of the renal vein. No more major complications occurred with increasing experience. From this porcine experiment, we conclude that the combination of laparoscopy, a tissue destroyer and an endobag for the entrapment of kidney seem to be a promising technique for clinical nephrectomy. 相似文献
25.
Metastatic septic endophthalmitis in pyogenic liver abscess 总被引:4,自引:0,他引:4
In a consecutive series of 180 patients with pyogenic liver abscess, three patients (two men and one woman, between 46 and 75 years of age) had metastatic Klebsiella endophthalmitis. The incidence of metastatic endophthalmitis was 1.7% in patients with pyogenic liver abscess, 5.2% in patients with Klebsiella liver abscess, and 7.8% in patients with Klebsiella liver abscess having Klebsiella bacteremia. Despite aggressive therapeutic measures, the men permanently lost their vision and the woman eventually required an evisceration of her right eye. Delayed recognition and/or treatment as well as the nature of bacteria probably contributed to the tragic outcome. The findings suggest that a high index of suspicion is critical and a combined effort of the internist and ophthalmologist is mandatory. 相似文献
26.
27.
Glucokinase gene is genetic marker for NIDDM in American blacks. 总被引:13,自引:0,他引:13
Glucokinase (ATP:D-glucose-6-phosphotransferase), expressed exclusively in liver and pancreatic islet beta-cells, catalyzes the first step of glycolysis and acts as glucose sensor and metabolic signal generator in these tissues. The enzyme plays a key role in glucose homeostasis and as such is an excellent candidate for inherited defects predisposing to non-insulin-dependent diabetes mellitus (NIDDM). A compound-imperfect dinucleotide (CA)n repeat element was found approximately 10-kb 3' of the human glucokinase gene on chromosome 7p, which revealed polymorphism with alleles differing in size by 2-15 nucleotides in unrelated individuals. A polymerase chain reaction assay was developed, and genomic DNA from 275 biologically unrelated American black individuals was typed for glucokinase alleles. The differences in allelic frequencies between individuals with NIDDM and nondiabetic individuals were compared. After typing 112 diabetic and 163 nondiabetic subjects, we found five different-sized alleles, with Z defined as the most common allele, Z + 2, Z + 4, Z + 10, and Z - 15. The Z allele was more common in nondiabetic subjects than in diabetic patients (60.4 vs. 49.6%, P = 0.012). The Z + 4 allele was more common in diabetic patients than in nondiabetic subjects (20.1 vs. 12.0%, P = 0.009). After adjusting for age, sex, and body mass index, the Z + 4 allele continued to have a positive association with NIDDM (P = 0.0018), and the Z allele had a negative association with NIDDM (P = 0.0334). The Z + 4 allele, transmitted as an autosomal dominant trait, appeared to be the most significant one at this locus.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
28.
Rats treated one week with flurazepam were killed while still on the drug or 48 h after termination of drug treatment. The brain 'microsac' preparation derived from the cerebral cortices was used for studying the GABA-stimulated chloride influx. There was no significant change in the basal or GABA-stimulated influx between control and treated groups. However, the effect of flunitrazepam to enhance 10 microM GABA-stimulated influx was significantly reduced, indicating tolerance. Methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3- carboxylate (DMCM), an 'inverse agonist' at benzodiazepine receptors, dose dependently inhibited 50 microM GABA-stimulated influx; chronic treatment did not alter the effect of DMCM. This study demonstrates that one week treatment with flurazepam produces tolerance to benzodiazepines without any change in the effect of GABA or DMCM. This indicates that GABA and benzodiazepine sites are differently modulated after chronic treatment with benzodiazepines. However, since both benzodiazepine and DMCM act on the same receptors it appears that the different 'domains' on the benzodiazepine receptor are differently altered during chronic treatment. 相似文献
29.
K S Leung W Y Shen H K Tsang K H Chiu P C Leung L K Hung 《The Journal of hand surgery》1990,15(1):11-17
One hundred cases of comminuted fracture of the distal radius were treated by a simple uniform method consisting of distraction by an external fixator for 3 weeks followed by functional bracing. During the application of the external fixator, autogenous cancellous bone chips were taken from the iliac crest and packed into the fracture site to realign the juxtaarticular fragments and to fill up the bone gap. Complications have been minimal. The results, after an average follow-up period of 20 months, taking into consideration subjective assessment of pain, objective measurement of wrist motion, and radiologic angles, have been excellent. 相似文献
30.
The major concern of the national population policy in Taiwan in recent years has been to lower the incidence of hereditary diseases and mental retardation in the general population. It has been estimated that there are around 10,000 mentally retarded school children in Taiwan. If effective chromosomal screening can be extended to these children, some of the family members who are carriers of balanced chromosomal rearrangements may benefit from follow-up studies and genetic counseling. The present report is the result of a pilot study conducted from 1988 to 1991 to explore the possibility of chromosomal screening of mentally retarded school children in Taipei. A total of 871 blood samples were collected from 1,147 children registered in 46 schools or residing in homes for the retarded. Chromosomal analysis was successfully accomplished on 674 out of 871 blood samples. The following chromosomal abnormalities were observed: 28 Down's syndrome, four Klinefelter syndrome, one XYY, one triple X, 11 translocations, seven inversions, four mosaics, three duplications, one deletion and one with an extra marker chromosome. After follow-up cytogenetic analyses of 13 families with probands with structural chromosomal anomalies, three of these families were shown to have one or two carriers of balanced translocated chromosomes. It seems that the present screening system would not be practical or cost-effective if it were applied island-wide in the future. 相似文献