全文获取类型
收费全文 | 881篇 |
免费 | 52篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 50篇 |
妇产科学 | 8篇 |
基础医学 | 70篇 |
口腔科学 | 65篇 |
临床医学 | 80篇 |
内科学 | 115篇 |
皮肤病学 | 8篇 |
神经病学 | 11篇 |
特种医学 | 189篇 |
外科学 | 124篇 |
综合类 | 74篇 |
预防医学 | 47篇 |
眼科学 | 4篇 |
药学 | 41篇 |
中国医学 | 24篇 |
肿瘤学 | 22篇 |
出版年
2024年 | 1篇 |
2022年 | 6篇 |
2021年 | 2篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 15篇 |
2017年 | 14篇 |
2016年 | 12篇 |
2015年 | 11篇 |
2014年 | 27篇 |
2013年 | 50篇 |
2012年 | 42篇 |
2011年 | 37篇 |
2010年 | 42篇 |
2009年 | 35篇 |
2008年 | 35篇 |
2007年 | 51篇 |
2006年 | 17篇 |
2005年 | 16篇 |
2004年 | 9篇 |
2003年 | 12篇 |
2002年 | 12篇 |
2001年 | 14篇 |
2000年 | 7篇 |
1999年 | 16篇 |
1998年 | 58篇 |
1997年 | 49篇 |
1996年 | 42篇 |
1995年 | 26篇 |
1994年 | 27篇 |
1993年 | 23篇 |
1992年 | 11篇 |
1991年 | 8篇 |
1990年 | 12篇 |
1989年 | 29篇 |
1988年 | 24篇 |
1987年 | 25篇 |
1986年 | 16篇 |
1985年 | 22篇 |
1984年 | 8篇 |
1983年 | 10篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 2篇 |
1978年 | 6篇 |
1977年 | 6篇 |
1976年 | 9篇 |
1975年 | 5篇 |
1954年 | 1篇 |
排序方式: 共有938条查询结果,搜索用时 15 毫秒
41.
A Papadopoulou MO Rawashdeh GA Brown AS McNeish IW Booth 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(1):79-83
The short- and long-term effects of an elemental diet in children with acute Crohn's disease were compared with those of prednisolone in historical controls. Clinical remission was induced in 25 of 30 and in 18 of 28 episodes treated for six weeks with an elemental diet and prednisolone. Patients with proximal disease had longer remission after treatment with an elemental diet (p < 0.05) than did patients with colonic disease after treatment with prednisolone (p < 0.01). Disease activity index score improved in both groups compared with the pretreatment scores (p < 0.05). However, the improvement in the elemental diet group was significantly better than in the prednisolone group (p < 0.001). Changes in linear growth were better after treatment with an elemental diet compared with steroids (p < 0.001). Serum albumin and haematocrit concentrations all improved significantly in the children treated with an elemental diet (p < 0.001) but not in those treated with steroids. Thus an elemental diet was better than prednisolone in proximal disease and confirmed improved growth and nutritional status. 相似文献
42.
OBJECTIVE: To retrospectively evaluate the outcome of artificial urinary sphincter (AUS) placement in 79 children, with a mean follow-up of 12.5 years. PATIENTS AND METHODS: A total of 89 children had an AUS placed between 1977 and 1994; complete data were obtained for 79 (63 boys and 16 girls). The indication for AUS placement was urinary incontinence caused by sphincteric deficiency with a stable bladder. Before and after surgery, all patients underwent ultrasonography, voiding cysto-urethrography and urodynamics. Logistic regression was used to assess the factors influencing the outcome. RESULTS: The mean (range) age at surgery was 11.7 (3-18) years. The cause of incontinence was a neuropathic bladder in 74 patients and bladder exstrophy in five. At a mean (range) follow-up of 12.5 (5-22) years, 63 of 79 patients (80%) had an intact AUS. The AUS was removed in 16 patients (20%) because of erosion at a mean (range) of 5.6 (1-11) years after insertion; there were 0.035 revisions per patient-year. Of 63 patients with an AUS in place, 57 (90%) are completely dry and 36 (57%) are using clean intermittent catheterization. Thirteen patients (20%) developed bladder instability during the follow-up, which was managed by anticholinergics in eight, spinal cord de-tethering in three and enterocystoplasty in two. Hydronephrosis occurred in 12 of 126 renal units (10%) that improved after enterocystoplasty or anticholinergics. The overall 10-year survival of the AUS was 79% (78% for early models and 80% for the AMS800); the survival was not affected by age, sex, model, previous bladder neck surgery, augmentation cystoplasty or intermittent catheterization. Bladder exstrophy was associated with lower AUS survival, as four of the five patients affected had the AUS removed secondary to erosion (P = 0.014). CONCLUSION: In children the AUS has a 79% 10-year survival and gives a 90% continence rate. Bladder instability after AUS placement can be managed with anticholinergics or enterocystoplasty. The AUS is not a justifiable treatment option for patients with bladder exstrophy. 相似文献
43.
目的 探索层流洁净技术治疗大面积烧伤的价值。方法 对室内空气及创面进行细菌培养;监测病房使用时间的细菌微粒数比较,各洁净级别杀菌率。不同级别地点细菌培养结果比较。结果 千级以上层流病房细菌培养为“0”,与普通病房对照有较大差别,患者死亡率明显降低,疗程缩短,医疗费用下降,手术植皮及其他伤口均达Ⅰ期愈合,无交叉感染。结论 层流洁净病房应用于烧伤治疗,疗效非常满意。 相似文献
44.
45.
Hafez AT Smith CR McLorie GA El-Ghoneimi A Herz DB Bägli DJ Khoury AE 《The Journal of urology》2001,166(4):1429-1432
PURPOSE: We compared tunica vaginalis applied as a flap versus a graft for covering defects in the ventral tunica albuginea in a rabbit model. MATERIALS AND METHODS: We used 18 New Zealand White rabbits in the study. The urethra was mobilized off of the corpus cavernosum. A defect was created in the ventral aspect of the tunica albuginea by excising a 1 x 0.5 cm. rectangular area. The defect was covered by the testicular surface of tunica vaginalis as a vascularized flap in 9 animals and as a graft in 9. At 2, 6 and 12-week intervals 3 animals per group were sacrificed. Transverse sections of the penis at the repair site were stained with hematoxylin and eosin, and Masson's trichrome for microscopy. RESULTS: Autopsy revealed no contracture in any of the tunica vaginalis flaps. In contrast, the tunica vaginalis grafts had contracted by a mean of 22% (range 20% to 25%) at 2, 38% (range 30% to 44%) at 6 and 42% (range 38% to 48%) at 12 weeks. Microscopic examination of the tunica vaginalis flaps showed evidence of an intact blood supply and viable cremasteric muscle layer but no evidence of necrosis. Collagen remodeling and maturation was noted at 12 weeks. In tunica vaginalis grafts there was evidence of necrosis of all tunica vaginalis layers at 2 weeks with granulation tissue and active fibrosis at the periphery. At 6 and 12 weeks most necrotic tissue was replaced by fibrosis. Osseous metaplasia was identified in 1 graft at 12 weeks. CONCLUSIONS: The optimal use of tunica vaginalis for correction of chordee is as a flap rather than as a free graft. Grafts were associated with significant necrosis and contracture, of which neither was associated with flaps. 相似文献
46.
Herz D Hafez A Bagli D Capolicchio G McLorie G Khoury A 《The Journal of urology》2001,166(5):1880-1886
PURPOSE: Subureteral injection of bulking agents is an accepted surgical treatment of vesicoureteral reflux in children. Polydimethylsiloxane, a silicone elastomer, is an ideal agent because of bulky consistency, lack of migration, minimal local inflammatory reaction and is safe in laboratory animals. We record our experience with endoscopic subureteral polydimethylsiloxane injection in children for vesicoureteral reflux. MATERIALS AND METHODS: During a 2-year period 16 boys and 58 girls, with an average age of 8 years, with 112 refluxing ureters underwent endoscopic subureteral polydimethylsiloxane injection to treat vesicoureteral reflux. Vesicoureteral reflux was grade I in 8, II in 43, III in 50, IV in 10 and V in 1 ureter. Operative indications were breakthrough urinary tract infection in 29 children, nonresolution of reflux 38 and high grade reflux 7. All procedures were on an outpatient basis and performed with patient under general anesthesia. All children had a postoperative ultrasound and voiding cystourethrogram at 12 weeks. Followup was from 6 to 24 months. RESULTS: Overall, reflux was corrected in 90 (81%) ureters and 56 (76%) children after a single injection. With repeat injection reflux was corrected in 101 (90%) ureters and 63 (85%) children. Correction by grade was 85%, 84%, 80%, 45% and 0% for grades I to V, respectively. With repeat injection correction was 100%, 92%, 90% and 55% for grades I to IV, respectively. There were no surgical complications. De novo contralateral reflux developed in 2 (3%) children. There were 3 (4%) children who required open ureteral reimplantation for failed injection. Detection of the polydimethylsiloxane implant by followup ultrasound was 89% sensitive and 86% specific for the correction of reflux. CONCLUSIONS: Endoscopic subureteral polydimethylsiloxane injection is an effective treatment of vesicoureteral reflux in children. The procedure is safe with low associated morbidity. The presence of the polydimethylsiloxane implant can be documented accurately by ultrasound, and there is a strong correlation between implant stability and correction of reflux. 相似文献
47.
Resistance of Copenhagen rats to chemical induction of glutathione S- transferase 7-7-positive liver foci 总被引:2,自引:0,他引:2
Copenhagen (Cop) rats are completely resistant to the chemical induction of
mammary adenocarcinomas, but their susceptibility to hepatocarcinogenesis
is virtually unknown. Rat liver is a well- characterized and easily
manipulated tissue in which to study carcinogenesis. Therefore, if Cop rats
are resistant to hepatocarcinogenesis, studies into resistance mechanisms
may be feasible. Male Cop and F344 rats, 7-8 weeks old, were initiated
using either N-nitrosodiethylamine (DEN) (200 mg/kg, i.p.) or a two-thirds
partial hepatectomy (PH) followed by N-methyl-N-nitrosourea (MNU) (60
mg/kg, i.p.). The rats were then promoted using a modified resistant
hepatocyte (RH) protocol (a combination of four doses of 2-
acetylaminofluorene (2-AAF) and a single dose of CCl4 that provides a
selective mitotic stimulus for initiated cells). Six weeks after initiation
the rats were killed and liver sections were stained for glutathione
S-transferase 7-7 (GST 7-7), a marker for putative preneoplastic
hepatocytes. Cop rats were found to be highly resistant, having a
approximately 9- and approximately 27-fold smaller percentage of liver area
occupied by GST 7-7-positive foci than susceptible F344 rats following
initiation by DEN and MNU respectively. Furthermore, gross liver nodules
did not form in any of the Cop rats, whereas all F344 rat livers contained
nodules. Hepatic necrosis caused by DEN during initiation, and CCl4 during
promotion is necessary to stimulate compensatory hepatocyte division. We
demonstrated that these agents do indeed increase serum transaminase levels
and produce histologic evidence of necrosis in Cop rats. In order for liver
foci to grow rapidly in the RH protocol, the surrounding normal hepatocytes
must be mito-inhibited by 2-AAF. We found that the degree of
mito-inhibition of normal hepatocytes by 2-AAF is the same in Cop and F344
rats. These results show that the Cop rat is highly resistant to the
chemical induction of putative preneoplastic liver foci and nodules.
相似文献
48.
GA McCarthy B Kampmann V Novelli RF Miller DE Mercey D Gibb 《Archives of disease in childhood》1996,74(5):455-457
AIDS related Kaposi's sarcoma is commonly seen in homosexual men, only occasionally in men and women with heterosexually acquired HIV, and extremely rarely in children. The case of an HIV infected mother and her vertically infected child who both developed visceral Kaposi's sarcoma is reported. It is proposed that the putative Kaposi's sarcoma agent may also be transmitted vertically. 相似文献
49.
Extracorporeal membrane oxygenation (ECMO) is a life support technique based on modifications of heart-lung bypass technology. It is used to support severe but potentially reversible pulmonary or cardiopulmonary failure. There is increasing use of the technique for neonates and a return of interest in its use for adults. The number of non-neonatal paediatric patients receiving pulmonary support with ECMO worldwide is, however, small, and survival rates average less than 50%. Initial experience in 15 patients aged 3 months to 5 years with a high survival and low morbidity is reported. 相似文献
50.
MJ Evans PA McKeever GA Pearson D Field RK Firmin 《Archives of disease in childhood》1994,71(2):F88-F92
The pathology was reviewed of the early deaths identified from the first 50 neonates treated with extracorporeal membrane oxygenation (ECMO) during its introduction to the UK. Fifteen neonates died during or shortly after ECMO between August 1989 and June 1992. Data on 12 are presented (three did not have a postmortem examination). The clinical diagnoses at referral for ECMO were as follows: persistent pulmonary hypertension of the newborn (six infants), primary congenital pneumonia (one infant), community acquired pneumonia (two infants), birth asphyxia (one infant), respiratory distress syndrome (one infant), and meconium aspiration syndrome (one infant). In our group, at necropsy, five had significant haemorrhage (three intracranial, one pulmonary, one pericardial and intraventricular). Three of five infants with evidence of haemorrhage also had signs of sepsis. Six infants had evidence at necropsy of systemic sepsis, five showed evidence of severe anoxic brain injury, and four infants had cerebellar haemorrhages. Three infants had evidence of myocardial ischaemia. It is difficult to discriminate between the relative influence of the primary diagnosis, the mode of treatment, and the severity of presentation in the genesis of this pathology. It is likely that the extent and severity of some of the findings represent a pathological progression that would have been interrupted by the death of the patient, had ECMO not been instituted. 相似文献