全文获取类型
收费全文 | 2400篇 |
免费 | 152篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 176篇 |
妇产科学 | 60篇 |
基础医学 | 403篇 |
口腔科学 | 43篇 |
临床医学 | 134篇 |
内科学 | 350篇 |
皮肤病学 | 41篇 |
神经病学 | 120篇 |
特种医学 | 63篇 |
外科学 | 440篇 |
综合类 | 49篇 |
一般理论 | 2篇 |
预防医学 | 155篇 |
眼科学 | 136篇 |
药学 | 239篇 |
中国医学 | 14篇 |
肿瘤学 | 128篇 |
出版年
2023年 | 12篇 |
2022年 | 35篇 |
2021年 | 90篇 |
2020年 | 51篇 |
2019年 | 59篇 |
2018年 | 63篇 |
2017年 | 61篇 |
2016年 | 66篇 |
2015年 | 82篇 |
2014年 | 117篇 |
2013年 | 154篇 |
2012年 | 171篇 |
2011年 | 220篇 |
2010年 | 103篇 |
2009年 | 75篇 |
2008年 | 125篇 |
2007年 | 133篇 |
2006年 | 124篇 |
2005年 | 111篇 |
2004年 | 112篇 |
2003年 | 101篇 |
2002年 | 78篇 |
2001年 | 46篇 |
2000年 | 34篇 |
1999年 | 31篇 |
1998年 | 22篇 |
1997年 | 18篇 |
1996年 | 14篇 |
1995年 | 15篇 |
1994年 | 15篇 |
1993年 | 16篇 |
1992年 | 28篇 |
1991年 | 17篇 |
1990年 | 10篇 |
1989年 | 13篇 |
1988年 | 12篇 |
1987年 | 17篇 |
1986年 | 11篇 |
1985年 | 11篇 |
1984年 | 13篇 |
1983年 | 5篇 |
1980年 | 3篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1975年 | 5篇 |
1974年 | 7篇 |
1973年 | 9篇 |
1972年 | 5篇 |
1971年 | 4篇 |
1970年 | 6篇 |
排序方式: 共有2563条查询结果,搜索用时 15 毫秒
1.
Aditya Kelkar Caroll Webers Rohit Shetty Jai Kelkar Nikhil Labhsetwar Abhishek Pandit Madhulika Malode Sayali Tidke 《Indian journal of ophthalmology》2020,68(10):2143
Purpose:To evaluate the rate of compliance and the reasons for loss to follow-up in Indian patients with diabetic macular edema (DME), age-related macular degeneration (AMD), and retinal vein occlusion (RVO) being treated with anti-vascular endothelial growth factor (VEGF) therapy.Methods:This was a retrospective single-center study. Patients with DME, AMD, or RVO were eligible if they initiated anti-VEGF therapy between January 2013 and December 2017. Patients'' data were obtained from hospital electronic records, including the number of injections received, visits, details of follow-up, missed appointments, and reasons for loss to follow-up (>365 days).Results:A total of 648 patients were eligible for the study, of which 334 (51.54%) patients were lost to follow-up. Overall, 343 (64.96%) were males and the overall mean (SD) age was 66.40 (7.44) years. A total of 376 (58.0%) patients had a history of diabetes and 364 (56.2%) patients had a history of hypertension. Further, 127 (38.0), 112 (33.5), and 95 (28.4) had DME, AMD, and RVO, respectively and were lost to follow-up. The most commonly reported reason for loss to follow-up was “non-affordability” (n = 120; 41.1%) followed by “no improvement in vision” (n = 83; 28.4%). “No improvement in vision” (42.2%) and “non-affordability” (37.5%) were higher among patients with DME. No association was found in gender- and treatment-wise distribution of reasons for loss to follow-up.Conclusion:The results showed that around half of the patients with DME, AMD, and RVO were lost to follow-up to intravitreal anti-VEGF therapy, and the most common factors were “non-affordability” and “no improvement in vision.” 相似文献
2.
Akshay Pratap Devendra Kumar Gupta Chandra Shekhar Agrawal Rakesh Kumar Pandit Shailesh Adhikary Anand Kumar Awadhesh Tiwari Satyendra Narayan Singh 《International journal of urology》2007,14(3):198-202
OBJECTIVES: We analyzed the methods and outcomes of urethroplasty in men with complex urethral disruptions. METHODS: The medical records of 40 men with complex urethral disruptions were analyzed. Surgical methods were individualized according to stricture location, severity and length of the stricture, bladder neck characteristics and presence of complicating factors. Patients were divided into four groups based on the above characteristics. RESULTS: End-to-end urethroplasty performed in six patients with short bulbar strictures (<3 cm) was successful in all. Elaborated perineal repair was performed in 10 patients with intermediate (3-6 cm) strictures with or without complicating factors. Elaborated perineal repair with urethral substitution was performed in nine patients with long segment stricture (>6 cm). Abdominal transpubic repair was successfully applied to patients with rectourethral fistula or lacerated bladder neck. Success rate of anastomotic urethroplasty was 95% while over all success rate was 85%. CONCLUSION: Guidelines for urethral reconstruction of complex urethral disruptions are predicated on stricture length, location, bladder neck characteristics and associated complicating factors. End-to-end urethroplasty with stricture excision is highly reliable for short strictures for which previous operative repair have failed. Elaborated perineal repair is extremely versatile for intermediate and longer strictures with associated complicating factors. Abdominal transpubic urethroplasty is effective for patients with rectourethral fistula or lacerated bladder neck. 相似文献
3.
M Vijaya Lakshmi MRCP G V Sridharan MRCP D Butterworth MRCP 《International journal of clinical practice》1993,47(3):164-165
Gallstones are common and their incidence increases with age.1 Fifty per cent of these stones are in the common bile duct (CBD) in the elderly.2 Most of them are silent but with time there is an increasing chance of developing symptoms which are more likely to be serious in the elderly.3 Failure to relieve mechanical obstruction of bile flow may lead to secondary biliary cirrhosis.4 It has been estimated that on average secondary biliary cirrhosis develops some seven years after the onset of obstruction from a stricture, four and half years after gallstone obstruction and 10 months after the onset of malignant stricture.5 The characteristic features are the pathological findings of portal-portal linkages, with a pattern of monolobular cirrhosis and the preservation of normal vascular relationships.6 Secondary biliary cirrhosis may lead to hepatic insufficiency and portal hypertension with the resultant complications, such as bleeding oesophageal varices, hypersplenism with pancytopenia, ascites and encephalopathy. We describe a patient in whom the diagnosis was not suspected until laparotomy and confirmed only at autopsy. 相似文献
4.
K K Sethi N Pandit M Bhargava J C Mohan R Arora M Khalilullah 《Indian heart journal》1992,44(3):145-149
The long term performance of various pacing leads in use for at least one year is reported from one centre. Between January 1975 and December 1990, 1056 cardiac pacing leads were implanted in 881 patients (mean age 57 +/- 13 years). Eight hundred and three leads were silicone insulated (SI) and 253 leads were polyurethane insulated (PUI). Leads from different manufacturers were used (Medtronic, CPI, Telectronics). The average duration of follow up was 56.6 +/- 77 months (range 12-221 months) for SI and 47.1 +/- 24 months (range 12-99 months) for PUI leads. Overall lead failure occurred more often in the PUI group (n = 46, 18.2%) compared to SI group (n = 93, 11.3%, p < 0.025). Majority of lead failures occurred in the first 36 months after implantation. In particular, Medtronic models 6971, 6972 (urethane) and 6901 (silicone) showed higher rate of complications (25.5%, 26.3% and 44.5% respectively). 相似文献
5.
6.
Treaba D Assad L Govil H Sariya D Reddy VB Kluskens L Green L Selvaggi SM Gattuso P 《Diagnostic cytopathology》2002,26(6):380-383
At the present time fine-needle aspiration (FNA) is considered a routine diagnostic procedure in evaluating neoplastic vs. nonneoplastic lesions in many organs, with high sensitivity and specificity. The purpose of this study was to assess the utility of FNA in areas of diagnostic difficulty and its limitations in evaluating bone lesions in patients with a previous history of malignancy. From 1989 to 2000, 249 CT-guided FNAs of bone lesion were performed at our institutions; 187/249 (75.1%) patients had a previous history of malignancy. Aspirated material was air-dried for Diff-Quik stain or fixed in ethanol for Papanicolaou staining. Subsequent surgical tissue was available in 69/187 (36.9%) of the cases. There were 114 males and 73 females, ages 14-86 yr (mean, 64 yr). The primary tumor site was lung 49, genitourinary 46, breast 31, gastrointestinal 28, hematopoietic 26, soft tissue/skin 5, and thyroid 2. There were 125 FNAs of the vertebral spine, 19 from the pelvis, 11 from the ribs, 9 from the sternum, 5 from the femur, and 18 from miscellaneous bone sites. Out of 187, 166 (88.7%) were malignant aspirates confirming the patients' primary malignancies. The most common malignancy encountered was adenocarcinoma, 126/187 (67.4%). Surgical tissue was available for review in 69 patients and the results were in agreement with the FNAs diagnosis in all cases. Nine out of 187 (4.8%) cases were diagnosed as marrow elements on cytological material. These patients have been followed for 1-9 yr and have failed to reveal signs or symptoms of clinical recurrence. Three out of 187 (1.6%) cases showed osteomyelitis. Nine out of 187 (4.8%) were unsatisfactory specimens, with biopsy follow-up available in four cases, showing three metastatic tumors and one case of osteomyelitis. FNA of metastatic bone lesions is a major step in pretreatment diagnosis. On satisfactory specimens, the cytological diagnosis viewed in the clinical-radiological context proves to be similar to surgical diagnosis. FNA is an excellent technique with a high accuracy rate in assessing metastatic bone lesions. 相似文献
7.
Bhattacharya B Sariya D Reddy VB Kluskens L Gould VE Gattuso P 《Diagnostic cytopathology》2002,26(6):384-386
A 4(1/2)-yr-old female presented with right-sided pleural effusion and a retroperitoneal mass. Cytologic analysis of the pleural fluid yielded malignant small round blue cells, which were noncohesive, 3-4 times the size of lymphocytes. The malignant cells had hyperchromatic, pleomorphic nuclei with moderate amounts of vacuolated cytoplasm. A few fiber-shaped cells were also seen. Immunostains for desmin, muscle-specific actin were positive; ultrastructural findings of thick and thin actin-myosin filaments confirmed the diagnosis of embryonal rhabdomyosarcoma. This case illustrates the importance of performing appropriate immunohistochemical stains and ultrastructural studies on cytological material to arrive at a definitive diagnosis. 相似文献
8.
Alan Ma Sunita Gurnasinghani Edwin P. Kirk Conor McClenaghan Gautam K. Singh Dorothy K. Grange Chetan Pandit Yung Zhu Tony Roscioli George Elakis Michael Buckley Bhavesh Mehta Philip Roberts Jonathan Mervis Andrew Biggin Colin G. Nichols 《American journal of medical genetics. Part A》2019,179(8):1585-1590
Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain‐of‐function mutations in the regulatory (SUR2) and pore‐forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel‐blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg–1 kg–1 day–1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg?1 kg?1day?1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS. 相似文献
9.
10.
Krishnamoorthy V Latash ML Scholz JP Zatsiorsky VM 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,152(3):281-292
Movements by a standing person are commonly associated with adjustments in the activity of postural muscles to cause a desired shift of the center of pressure (COP) and keep balance. We hypothesize that such COP shifts are controlled (stabilized) using a small set of central variables (muscle modes, M-modes), while each M-mode induces changes in the activity of a subgroup of postural muscles. The main purpose of this study has been to explore the possibility of identification of muscle synergies in a postural task using the framework of the uncontrolled manifold (UCM) hypothesis employing the following three steps in data analysis: (i) Identification of M-modes: Subjects were asked to release a load from extended arms through a pulley system, resulting in a COP shift forward prior to load release. Electromyographic (EMG) activity of eleven postural muscles on one side of the body was integrated over a 100 ms interval corresponding to the early stage of the COP shift, and subjected to a principal component (PC) analysis across multiple repetitions of each task. Three PCs were identified and associated with a push-back M-mode, a push-forward M-mode and a mixed M-mode. (ii) Calculation of the Jacobian of the system, which relates changes in the magnitude of M-modes to COP shifts using regression techniques: Subjects performed three different tasks (releasing different loads at the back, voluntarily shifting body weight forward and backward, at different speeds) to verify if the relationship between magnitudes of M-modes and COP shifts is task or direction specific. (iii) UCM analysis: Three tasks were chosen (load release in the front, arm movement forward and backward) which were associated with an early shift in COP. A manifold was identified in the M-mode space corresponding to a certain average (across trials) shift of the COP and variance per degree of freedom within the UCM (VUCM) and orthogonal (VORT) to the UCM was computed. Across subjects, VUCM was significantly higher than VORT when analysis at the third step was performed using a Jacobian computed based on a set of tasks associated with a COP shift in the same direction but not in the opposite direction. This result confirms our hypothesis that the M-modes work together as a synergy to stabilize a desired shift of the COP. Forward and backward COP shifts are associated with different synergies based on the same three M-modes.An erratum to this article can be found at 相似文献