全文获取类型
收费全文 | 2241篇 |
免费 | 101篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 52篇 |
儿科学 | 164篇 |
妇产科学 | 23篇 |
基础医学 | 220篇 |
口腔科学 | 71篇 |
临床医学 | 93篇 |
内科学 | 524篇 |
皮肤病学 | 10篇 |
神经病学 | 254篇 |
特种医学 | 31篇 |
外科学 | 206篇 |
综合类 | 83篇 |
预防医学 | 127篇 |
眼科学 | 137篇 |
药学 | 230篇 |
中国医学 | 11篇 |
肿瘤学 | 115篇 |
出版年
2022年 | 25篇 |
2021年 | 52篇 |
2020年 | 32篇 |
2019年 | 34篇 |
2018年 | 53篇 |
2017年 | 24篇 |
2016年 | 29篇 |
2015年 | 37篇 |
2014年 | 44篇 |
2013年 | 54篇 |
2012年 | 89篇 |
2011年 | 97篇 |
2010年 | 54篇 |
2009年 | 43篇 |
2008年 | 87篇 |
2007年 | 78篇 |
2006年 | 91篇 |
2005年 | 74篇 |
2004年 | 59篇 |
2003年 | 73篇 |
2002年 | 64篇 |
2001年 | 51篇 |
2000年 | 64篇 |
1999年 | 72篇 |
1998年 | 25篇 |
1997年 | 19篇 |
1996年 | 22篇 |
1993年 | 19篇 |
1992年 | 61篇 |
1991年 | 78篇 |
1990年 | 37篇 |
1989年 | 68篇 |
1988年 | 56篇 |
1987年 | 60篇 |
1986年 | 60篇 |
1985年 | 35篇 |
1984年 | 25篇 |
1983年 | 18篇 |
1982年 | 16篇 |
1979年 | 33篇 |
1978年 | 16篇 |
1977年 | 24篇 |
1975年 | 19篇 |
1974年 | 39篇 |
1973年 | 35篇 |
1972年 | 26篇 |
1971年 | 22篇 |
1970年 | 15篇 |
1969年 | 17篇 |
1966年 | 20篇 |
排序方式: 共有2351条查询结果,搜索用时 0 毫秒
1.
Background
Traumatic perforation of the distal oesophagus due to blunt trauma is a very rare condition and is still associated with a significant morbidity and mortality. This is further exacerbated by delayed diagnosis and management as symptoms and signs are often masked by or ascribed to more common blunt thoracic injuries. 相似文献2.
Y K Murali P Anand V Tandon R Singh R Chandra P S Murthy 《Experimental and clinical endocrinology & diabetes》2007,115(10):641-646
The aqueous extract of the fruits of Terminalia chebula Retz. has been evaluated for its antidiabetic activity in streptozotocin (STZ) induced mild diabetic rats and compared with a known drug, tolbutamide. The oral effective dose (ED) of the extract was observed to be 200 mg/kg body weight, which produced a fall of 55.6% (p<0.01) in the oral glucose tolerance test. Oral administration of ED of aqueous extract of T.chebula (AETC) daily once for two months reduced the elevated blood glucose by 43.2% (p<0.01) and significantly reduced the increase in glycosylated hemoglobin (HbA1c) (p<0.01). The same dose also showed a marked improvement in controlling the elevated blood lipids as well as decreased serum insulin levels in contrast to the untreated diabetic animals. Hepatic and skeletal muscle glycogen content decreased by 75% and 62.9% respectively in diabetic controls, these alterations were partly prevented (34.9% and 21.17%) in AETC treated group when compared to the healthy controls. The in vitro studies with pancreatic islets showed that the insulin release was nearly two times more than that in untreated diabetic animals. The treatment did not have any unfavorable effect on other blood parameters of liver and kidney function tests. LD 50 was found to be above 3 g/kg bw i.e. 15 times of ED, because there were no deaths of animals even at this dose indicating high margin of safety. These findings suggest further investigations for the possible use of the aqueous extract of fruits of T.chebula for the treatment of diabetes. 相似文献
3.
Previous pharmacological studies with the pituitary gland have suggested that acetylcholine (ACh) might be involved in the regulation of intermediate lobe (IL) function. Whether ACh is endogenous to the IL cells or provided from an extrinsic source is unclear. The present experiments tested the possibility that the endocrine cells of the IL may be a source of ACh by measuring certain cholinergic markers in a primary culture of dissociated porcine cells. The endogenous ACh content was readily measurable in both the freshly dissociated IL cells and in 2- or 4-day primary cultures. Choline acetyltransferase activity was also measurable in the freshly dissociated and cultured IL cells and was reduced by 53% in the presence of a specific inhibitor, napthylvinylpyridine (50 μM). IL cells incubated in the presence of [14C]choline (1 μM) were able to synthesize [14C]ACh and the accumulation of the new ACh was inhibited by hemicholinium-3 (30 μM), a competitive inhibitor of high affinity choline uptake at cholinergic nerve terminals. In conclusion, these results demonstrate that the endocrine cells of the IL are capable of synthesizing and storing ACh. 相似文献
4.
Sandeep Nijhawan Mukul Rastogi Ashish Joshi Atul Shende Manish Tandon Dinesh Singla Amit Mathur Subhash Nepalia Ramesh Roop Rai 《Digestive endoscopy》2007,19(2):80-82
Background: Ingestion of coins is a common clinical problem in children. Many of the coins are ferromagnetic and can be retrieved with the help of a magnet. We describe the use of a novel endoscopic accessory for removing ferromagnetic coins. Material and methods: Two magnet discs of 1.5 cm diameter were joined to a 200 cm steel wire of 0.75 mm thickness with a terminal 5 cm spring. A Teflon tube (160 cm, 7 F) was used along with this instrument as a sleeve. The use of this accessory was analyzed prospectively in subjects presenting with a history of coin ingestion. The time taken for removal of coins, complications during the procedure and failure rate was noted. Effect of the magnet on cardiac rhythm was also noted during the procedure. Results: A total of 55 children (mean age 5.1 ± 2.3 years) with coin ingestion presented over a period of 1 year. Forty‐four coins were ferromagnetic. All ferromagnetic coins were removed successfully. Mean time for removal was 68 ± 22 s. No complications were encountered. Conclusion: The novel magnetic instrument is precise, safe and quick for the removal of ferromagnetic coins under direct vision. 相似文献
5.
Vishwa Prakash Raman Tandon Raghav Mantri 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(10):1102-1104
Supragaleal placement of tissue expander for management of alopecia of scalp excludes tough galeal layer so that easier and faster expansion of scalp may be achieved. 相似文献
6.
7.
Richard Lehman Frederick Andermann ré Olivier Prakash N. Tandon Luis F. Quesney Theodore B. Rasmussen 《Epilepsia》1994,35(6):1117-1124
Summary: It is not generally appreciated that intractable seizures involving the face area are amenable to surgical treatment. Twenty patients with onset of sensorimotor seizures in the face area of the pre- and postcentral gyri have been studied and surgically treated since 1948. Seizures started in the face, tongue, or throat, followed by diverse patterns depending on spread of seizure activity. Two patients had epilepsia partialis continua; 6 had either tonic or atonic drop attacks. All patients had pre- and postcentral face area resections, 12 in the dominant hemisphere. In addition, 3 had more extensive postcentral removal, 7 had temporal lobe, and 4 had small separate or contiguous frontal or parietal resection. Because the seizures were not sufficiently reduced by the first operation, 6 required reoperation; 4 of these patients had residual epileptiform activity on electrocorticogram (ECoG) after the first resection. Three patients had new neurologic signs that did not return to the preoperative level, but in 2 of them the deficit related mainly to higher resection in the central area. All but 2 of these 20 patients had at least moderate seizure reduction. Corticectomy can be performed for treatment of seizures arising in the lower central area and usually does not lead to significant permanent neurologic deficit. 相似文献
8.
M Tandon S Singh L Xu P Kumar L I Wiebe E E Knaus W P Gati M L Tempest 《Drug design and discovery》1992,9(1):79-91
The synthesis of the two diastereomers (9 and 10) of 5-(2,2-difluorocyclopropyl)-2'-deoxyuridine are described. Their antiviral and cytotoxic activities were determined, in comparison with (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) and 5-fluoro-2'-deoxyuridine (FDU), respectively. 5-[(1R)-2,2-Difluorocyclopropyl]-2'-deoxyuridine (10) was the most active antiviral agent against HSV-1 (IC50 = 5 micrograms/ml) relative to BVDU (IC50 = 0.082 micrograms/ml), and cytotoxic agent in the CCRF-CEM (IC50 = 230 microM) screen relative to FDU (IC50 = 4.7 x 10(-3) microM). The 5-[(1S)-2,2-difluorocyclopropyl] diastereomer was inactive in both screens. Partition coefficients (P) and affinity for the mouse erythrocyte nucleoside transporter (Ki) were not determinants of antiviral or cytotoxic activities. However, the (1R)-diastereomer (10) was more resistant to glycosidic bond cleavage by thymidine phosphorylase than the (1S)-diastereomer (9). 相似文献
9.
T cell responses to orbital antigens in thyroid-associated ophthalmopathy. 总被引:3,自引:1,他引:2
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
K Arnold N Tandon R S McIntosh R Elisei M Ludgate A P Weetman 《Clinical and experimental immunology》1994,96(2):329-334
Thyroid-associated ophthalmopathy (TAO) is most likely to be a T cell-mediated disease, in which cytokines released in the extraocular muscles activate fibroblasts, increasing glycosaminoglycan production. The nature of the orbital antigen recognized by the infiltrating T cells is unclear, although it is possible that there is cross-reactivity between this and a thyroid autoantigen to explain the close association with thyroid autoimmunity. We have tested the ability of human and porcine eye muscle antigen preparations to stimulate proliferation of circulating T cells from healthy subjects and patients with TAO or Graves' disease without clinical TAO. Occasional responses were seen, particularly after depletion of CD8+ T cells, and two out of 10 TAO patients responded to eye muscle proteins of 25-50 kD after fractionation of antigens on gels and subsequent elution. There was no disease-specific response of T cells to R1, R14, D1 and 1D3, recombinant proteins identified from screening an eye muscle cDNA library with sera from patients with autoimmune thyroid disease. We have also found that interferon-gamma (IFN-gamma) production by T cells from TAO patients was not stimulated by eye muscle membrane antigens or by 1D3. These results suggest that the frequency of circulating T cells responding to eye muscle antigens in TAO is low, and that several candidate orbital antigens, including the 64-kD protein 1D3, are unlikely to be important T cell autoantigens in this condition. 相似文献
10.
Preventive and therapeutic role of vitamin E in chronic plumbism 总被引:1,自引:0,他引:1
The ability of vitamin E to prevent or treat experimental lead intoxication was investigated in rats. Lead ingestion (10 mg/kg, lead as lead acetate, orally for 6 weeks) significantly inhibited the activity of blood delta-aminolevulinic acid dehydratase (ALAD), reduced the brain dopamine (DA) contents, enhanced the blood zinc protoporphyrin, and enhanced the urinary excretion of delta-aminolevulinic acid (ALA). Lead exposure also elevated brain norepinephrine, homovanillic acid, and 5-hydroxyindole acetic acid (5-HIAA) levels and concentration of lead in blood and tissue. Simultaneous supplementation of vitamin E along with lead significantly reduced the inhibition of blood ALAD activity, brain DA and 5-HIAA levels, and elevation of urinary ALA excretion. Blood and liver lead concentrations were also significantly reduced by simultaneous supplementation with vitamin E. Postlead exposure treatment with vitamin E was ineffective in reducing the lead-induced effects, except that the inhibition of blood ALAD activity was slightly reduced. The present results suggest that vitamin E given simultaneously with lead is effective in reducing the severity of lead intoxication. 相似文献