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31.
Sixty strains of Riemerella anatipestifer were isolated from ducks and geese with infectious serositis in Taiwan. Sixty per cent of the isolates (36/60) contained a 3.9 b plasmid, 12% (7/60) contained 6.5 b and 16 b plasmids, 5% (3/60) contained 2.9, 16 and 18 b plasmids and 13% contained no plasmid (14/60). The 3.9 b plasmid (designated as pCFC1) was completely sequenced to determine if it encoded virulence factors. pCFC1 was 27% G-C and had four large open reading frames (ORF). Two of the ORFs (designated as VapD1 and VapD2) encoded proteins that shared 80, 83, 69 and 67 (VapD1) and 50, 48, 21 and 20% (VapD2) identity with virulence-associated proteins of Actinobacillus Actinomycetemcomitans, Dichelobcater nodosus, Haemophilus influenzae and Neisseria gonorrheae, respectively. pCFC1 also had an ORF (designated as RepAl) that encoded a protein with approximately 30% identity to the RepA proteins of Neisseria gonorrhoeae, Campylobactor hyointestinalis and Pseudomonas aeroginosa. The region upstream of the RepA ORF had an A-T-rich region that was followed by four 21 bp perfect and one 20 bp imperfect direct repeat. The fourth ORF (designated as RepA2) encoded a protein with a region that was 44% homologous to the Helicobactor pylori replication protein.  相似文献   
32.
Knife injuries can be classified into stabbing injuries and multiple laceration or multiple chops, the latter being much more common in Chinese communities. It is the mark of criminal gang attacks with their tendency to use long knives and choppers rather than guns. The intention is often to wound rather than kill. A survey of 89 cases revealed that 90% of the victims are men, with a mean age of 27 years; 75% was admitted to the hospital at night, and in 78% of the cases the assailants were persons unknown, or so we were told by the victims. The reasons for the attacks were also not given. Most of the women victims were assaulted by their spouse. Some 74% of the patients suffered three to six lacerations; 62% of the injuries were on the extensor surfaces of the upper limbs, while the hand and the back of the trunk were also common sites. The type of management differs from that for stabbing injuries. There were no fatalities, and less than half of the patients required blood transfusion. The average hospital stay was 6.2 days. The morbidity of these injuries involves damaged tendons and nerves.  相似文献   
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The vascular anatomy of the pronator quadratus muscle and distal radius was studied in 24 cadaveric forearms by dissection under magnification and india ink and latex injection studies. The anterior interosseous artery divides into a muscular branch and a dorsal branch 1 cm to 3.5 cm from the proximal margin of the pronator quadratus muscle, and on its deep surface. Injection studies showed a rich periosteal plexus contributed by the anterior interosseous artery. Retrograde injection through the dorsal branch also showed good perfusion of the distal radius that was confirmed microscopically on bone sections. A muscle-bone graft from the anteromedial cortex of distal radius with an intact anterior interosseous artery has mobility of less than 2 cm. After ligating and dividing the anterior interosseous artery, blood supply to the distal radius bone flap relies on a retrograde flow and the bone flap could then be mobilized distally up to 4 to 6 cm.  相似文献   
35.
Previously, we reported that transgenic mice overexpressing endothelin-1 in astrocytes showed more severe neurological deficits and increased infarct after transient focal ischemia. In those studies, we also observed increased level of aldose reductase (AR), the first and rate-limiting enzyme of the polyol pathway, which has been implicated in osmotic and oxidative stress. To further understand the involvement of the polyol pathway, the mice with deletion of enzymes in the polyol pathway, AR, and sorbitol dehydrogenase (SD), which is the second enzyme in this pathway, were challenged with similar cerebral ischemic injury. Deletion of AR-protected animals from severe neurological deficits and large infarct, whereas similar protection was not observed in mice with SD deficiency. Most interestingly, AR(-/-) brains showed lowered expression of transferrin and transferrin receptor with less iron deposition and nitrotyrosine accumulation. The protection against oxidative stress in AR(-/-) brain was also associated with less poly(adenosine diphosphate-ribose) polymerase (PARP) and caspase-3 activation. Pharmacological inhibition of AR by Fidarestat also protected animals against cerebral ischemic injury. These findings are the first to show that AR contributes to iron- and transferrin-related oxidative stress associated with cerebral ischemic injury, suggesting that inhibition of AR but not SD may have therapeutic potential against cerebral ischemic injury.  相似文献   
36.
Frontal intracerebral haemorrhage (ICH) is a common result of cranial trauma. Outcome differences between bilateral and unilateral frontal ICH are not well studied but would be valuable to predict prognosis in clinical practice. Two aims are proposed in this study: first to compare the risk of developing delayed ICH after bilateral or unilateral frontal ICH, and second to determine the variables helpful to predict outcome according to the Glasgow Outcome Scale (GOS). Between January 1993 and December 1997, 694 consecutive patients with traumatic ICH were admitted to the Chang Gung Medical Center within 24 h of the trauma. Patients with ICH in sites other than the frontal lobes were excluded. A total of 161 cases (mean age 46.3+/-20.3 years), including 57 bilateral (mean age 52.5+/-18.7 years) and 104 unilateral (mean age 42.9+/-20.5 years) traumatic frontal ICH were studied. Twenty-eight of 57 patients (49%) with bifrontal ICH versus 17 of 104 patients (16%) with unilateral frontal ICH had a further, delayed ICH. In 42 of 45 patients (93%) with delayed ICH, this occurred within 5 days of the initial trauma. Multivariate logistic regression was used to select significant predictors of outcome. We found that delayed ICH (p<0.001), age (p=0.004) and mechanism of injury (p=0.001) explained the worse outcome in patients with bifrontal ICH. The best-fitting logistic regression model included three variables: delayed ICH (p=0.011), initial GCS (p=0.023), and a sum score of clinical and radiological variables (p=0.003). Bifrontal ICH tended to occur in older patients after a fall and was associated with a higher risk of developing delayed ICH or brain stem compression compared to unilateral ICH damage. Using these three variables - delayed ICH, initial GCS, and the sum score - in a logistical regression model is useful to predict outcome in patients with traumatic frontal ICH and may aid patient management.  相似文献   
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38.
Carcinoids of the pancreas are exceedingly rare tumors that orieinate from the enterochromaffin cells of the gastroenteropancreatic neuroendocrine system. According to a recent report,1 pancreatic carcinoids are found in only 0.58% (79/13 715 cases) of the entire carcinoid group. Todate, very limited information regarding the detection and diagnosis of this entity has been reported in the available literature. Although pancreatic carcinoid tumors grow.  相似文献   
39.
多沙唑嗪与特拉唑嗪治疗原发性高血压的疗效比较   总被引:3,自引:0,他引:3  
目的:比较甲磺酸多沙唑嗪和特拉唑嗪治疗原发性高血压的疗效和安全性.方法:采用随机单盲平行对照试验,将符合条件的轻、中度高血压患者63例随机分为试验组(多沙唑嗪)和对照组(特拉唑嗪).试验剂量从2 mg开始逐渐递增至2~8 mg/d,疗程4周.治疗前后分别行心电图、常规体检、血尿常规和生化检查.结果:①治疗4周后,多沙唑嗪组降压总有效率80.7%,特拉唑嗪组降压总有效率70.0%.两组间无显著性差异.②多沙唑嗪组治疗前后收缩压、舒张压的下降幅度分别为10.81%、10.70%,特拉唑嗪组为10.01%、11.47%.两组间无显著性差异.③多沙唑嗪组有效剂量2~6 mg/d,平均3.04 mg/d,特拉唑嗪组有效剂量2~8 mg/d,平均4.19 mg/d.④每组不良事件发生率相似,多沙唑嗪组25.8%,特拉唑嗪组33.3%(P>0.05).最常见的不良反应为头晕、头痛、心悸、体位性低血压等,多为轻度,可迅速缓解,多沙唑嗪组未发生体位性低血压.结论:甲磺酸多沙唑嗪2~6 mg/d,一天一次口服治疗轻、中度高血压安全有效.  相似文献   
40.
目的 :探讨自身免疫性白内障 (AIC)的病理生理学机制。 方法 :采用酶组织化学方法以及晶状体生理功能检查 ,观察AIC模型动物晶状体生理功能与组织内主要酶活性的变化。 结果 :晶状体组织内Na K ATP酶活性降低与晶状体调节力下降、裂隙灯下显微镜混浊改变之间存在着相关性。 结论 :自身免疫性晶状体损伤 ,进而造成晶状体组织内相关酶代谢异常是AIC的病理基础  相似文献   
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