全文获取类型
收费全文 | 8315篇 |
免费 | 432篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 115篇 |
儿科学 | 455篇 |
妇产科学 | 118篇 |
基础医学 | 897篇 |
口腔科学 | 144篇 |
临床医学 | 612篇 |
内科学 | 1681篇 |
皮肤病学 | 83篇 |
神经病学 | 653篇 |
特种医学 | 283篇 |
外科学 | 1283篇 |
综合类 | 239篇 |
一般理论 | 1篇 |
预防医学 | 429篇 |
眼科学 | 427篇 |
药学 | 772篇 |
中国医学 | 89篇 |
肿瘤学 | 494篇 |
出版年
2023年 | 66篇 |
2022年 | 147篇 |
2021年 | 321篇 |
2020年 | 131篇 |
2019年 | 194篇 |
2018年 | 272篇 |
2017年 | 195篇 |
2016年 | 221篇 |
2015年 | 238篇 |
2014年 | 336篇 |
2013年 | 463篇 |
2012年 | 638篇 |
2011年 | 665篇 |
2010年 | 379篇 |
2009年 | 339篇 |
2008年 | 486篇 |
2007年 | 462篇 |
2006年 | 372篇 |
2005年 | 393篇 |
2004年 | 310篇 |
2003年 | 273篇 |
2002年 | 289篇 |
2001年 | 136篇 |
2000年 | 116篇 |
1999年 | 117篇 |
1998年 | 72篇 |
1997年 | 40篇 |
1996年 | 43篇 |
1995年 | 30篇 |
1993年 | 38篇 |
1992年 | 59篇 |
1991年 | 81篇 |
1990年 | 80篇 |
1989年 | 72篇 |
1988年 | 52篇 |
1987年 | 60篇 |
1986年 | 36篇 |
1985年 | 55篇 |
1984年 | 39篇 |
1983年 | 38篇 |
1982年 | 28篇 |
1981年 | 33篇 |
1979年 | 26篇 |
1978年 | 27篇 |
1977年 | 25篇 |
1976年 | 22篇 |
1975年 | 23篇 |
1973年 | 33篇 |
1971年 | 24篇 |
1969年 | 24篇 |
排序方式: 共有8775条查询结果,搜索用时 93 毫秒
1.
Uday Yanamandra Prateek Deo Kamal Kant Sahu Ram Vasudevan Nampoothiri Nalini Gupta Anusree Prabhakaran Deb Prasad Dhibhar Alka Khadwal Gaurav Prakash Man Upadesh Singh Sachdeva Deepesh Lad Neelam Varma Subhash Varma Pankaj Malhotra 《Clinical Lymphoma, Myeloma & Leukemia》2019,19(3):183-189.e1
Background
Multiple myeloma (MM) is a hematologic malignancy of plasma cell origin. MM primarily affects bone marrow, but extramedullary sites can also be involved. Myelomatous pleural effusion (MPE) is an atypical and rare complication of MM. We aimed to systematically study the incidence and clinicopathologic profile of patients with MPE in a real-world setting.Patients and Methods
In this retrospective study, 415 consecutive patients with MM managed at a tertiary care center in North India during a study period of January 1, 2010 to December 31, 2015 were evaluated for MPE. The patients with MPE were analyzed for their clinical profile, diagnosis, treatment, and outcomes.Results
Of these 415 patients, 11 (2.65%) patients had MPE. The median age of the study population was 50 years with male preponderance. The majority of these patients had immunoglobin (Ig)G Kappa disease. All patients had higher than International Staging System stage I disease. MPE was a presenting feature at MM diagnosis in 45.45% (n = 5) of the patients, whereas the rest developed MPE during follow-up. MPE presented predominantly (81.8%) as a unilateral effusion. Concurrent extramedullary involvement at other site was seen in 45.45% (n = 5), with 3 (27%) patients having concurrent myelomatous ascites. Six of these were managed aggressively, whereas 5 patients opted for palliation. The outcomes were dismal (90.9% mortality), with a median survival of 2.47 months.Conclusion
MPE is a rare entity, and positive outcomes of therapy remain low with dismal prognosis. 相似文献2.
Advait Prakash Bhavesh Doshi Sangram Singh Tanmay Vyas Anvesh Jain 《African Journal of Paediatric Surgery》2015,12(1):82-85
Intussusception is a very rare cause of intestinal obstruction in neonates. It is of extremely rare occurrence among premature neonates. We present a case of 11-day-old premature neonate who presented with abdominal distension, intolerance to feeds, vomiting, significant bilious aspirate and bleeding per rectum. The initial diagnosis of necrotizing enterocolitis (NEC) led to a delay in the diagnosis. On exploratory laparotomy, it turned out to be a case of ileo-colic intussusception with Meckel''s diverticulum as a lead point. This site of intussusception (ileo-colic) and presence of a lead point among premature neonate is of exceedingly rare occurrence and very few such cases have been reported.In this article, the published work about clinical features and management on intussusceptions in premature neonates has been reviewed. The authors intend to highlight the difficulty in distinguishing the NEC and intussusception. Subtle clinical and radiological features which can help in differentiating the two conditions have been emphasized. This can avoid the delay in diagnosis and management which can prove critical. High index of suspicion with timely intervention is the key for optimizing outcome. A diagnosis of intussusception should always be considered in any preterm infant with suspected NEC. 相似文献
3.
4.
5.
Elaboration by mammalian mesenchymal cells infected with Trypanosoma cruzi of a fibroblast-stimulating factor that may contribute to chagasic cardiomyopathy. 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Myocardial fibrosis can occur as a complication of chronic infection of the heart with Trypanosoma cruzi (Chagas' disease) and can lead to serious disability. To assess whether there might be a direct relationship between intracellular parasitization and subsequent tissue fibrosis in this disease, we tested serum-free conditioned media from cultures of fibroblasts, vascular smooth-muscle cells, and myocardial cells for fibroblast-stimulating activity. Conditioned media from all infected cultures, but not from uninfected cultures, stimulated fibroblast [3H]thymidine incorporation, DNA and protein synthesis, and cell proliferation. Fibroblast-stimulating activity was also detected in extracts of amastigotes but not of trypomastigotes or epimastigotes. We conclude that parasitization of mesenchymal cells, including myocardial cells, results in elaboration of a fibroblast-stimulating factor(s), perhaps of parasite origin. We postulate that this factor may play a role in initiation of myocardial fibrosis in Chagas' disease. 相似文献
6.
Ziprasidone (Geodone), a novel atypical antipsychotic agent, is recently approved for the treatment of schizophrenia. It undergoes extensive metabolism in preclinical species and humans after oral administration, and only a very small amount of administered dose is excreted as unchanged drug. In vitro studies using human liver microsomes have shown that the oxidative metabolism of ziprasidone is mediated primarily by CYP3A4. However, coadministration of ziprasidone with ketoconazole, a CYP3A4 inhibitor, showed only a modest increase in its exposure. Therefore, in vitro metabolism of ziprasidone was investigated in hepatic cytosolic fractions to further understand its clearance mechanisms in preclinical species and humans. The major metabolite from incubation of ziprasidone in cytosolic fractions of rat, dog, and human was characterized by liquid chromatography-tandem mass spectrometry and found to be the product of reductive cleavage. Derivatization and hydrogen/deuterium exchange were used to deduce that the addition of two hydrogen atoms had occurred at the benzisothiazole moiety. Further studies to determine the enzyme involved in the formation of this metabolite are currently in progress. The identification of this novel metabolite in cytosol has clarified the clearance mechanism of ziprasidone in humans and preclinical species. 相似文献
7.
A model is developed to describe protein release kinetics from injectable, polymer solution depots which undergo rapid phase inversion on injection. The model consists of a polymer-rich phase and a solvent-rich phase, consistent with experimentally observed phase inversion morphology. Equations in the polymer-rich phase are based on diffusion-reaction mass balances for solvent, water and dissolved drug, and the rate of dissolution of dispersed drug particles. Equations in the water-rich phase are also of the diffusion-reaction type. Transport parameters in the polymer-rich phase are coupled to the ternary thermodynamics through friction formalism, and remaining parameters are estimated from literature data, leaving two free parameters: volume fraction of water-rich phase (epsilon) and k, the mass-transfer coefficient for bath-side transfer of the protein. Variations of these parameters lead to predictions of release profiles that vary from a rapid, burst-like behavior followed by a locking-in of the polymer-rich phase, to a uniform, zero-order profile. Comparisons are made to lysozyme release data for three systems: PLGA solutions in N-methlypyrollidinone (NMP), PLA solutions in NMP, and the latter with added Pluronic. Good agreement between model predictions and data is shown; in particular, the transition from rapid release to zero-order kinetics that occurs on addition of Pluronic is illustrated. 相似文献
8.
9.
10.
Hand-assisted laparoscopic nephroureterectomy for upper urinary tract transitional cell carcinoma. 总被引:1,自引:0,他引:1
Jay D Raman Michael A Palese Casey K Ng Stephen A Boorjian Douglas S Scherr Joseph J Del Pizzo R Ernest Sosa 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(4):432-438
OBJECTIVE: We report our experience with hand-assisted laparoscopic nephroureterectomy (HALN) for upper urinary tract transitional cell carcinoma and compare our results with a contemporary series of open nephroureterectomy (ON) performed at our institution. METHODS: Between August 1996 and May 2003, 90 patients underwent nephroureterectomy for upper-tract transitional cell carcinoma (TCC). Thirty-eight patients underwent HALN, while 52 had an ON. End-points of comparison included operative time, estimated blood loss (EBL), intraoperative and postoperative complications, length of hospital stay, pathologic grade and stage of tumor, and tumor recurrence. RESULTS: The mean patient age was 72.3 and 70.6 years in the ON and HALN groups, respectively. Mean operative duration was 243 minutes (ON) and 244 minutes (HALN), with an EBL of 478mL in the open group versus 191 mL in the hand-assisted group (P<0.001). No intraoperative complications occurred, but postoperative complications occurred in 4% and 11% of the ON and HALN groups, respectively (P=0.21). The mean hospital duration was 7.1 days (ON) versus 4.6 days (HALN) (P<0.01). No difference existed in the pathologic grade or stage distribution of urothelial tumors between the 2 groups. The mean follow-up was 51.0 months in the ON group and 31.7 months in the HALN group. Recurrence of urothelial carcinoma occurred in 50% of patients who underwent ON and 40% treated by HALN (P=0.38) at a median interval of 9.1 and 7.7 months, respectively, after surgery. CONCLUSION: Hand-assisted laparoscopic nephroureterectomy is an effective modality for the treatment of upper urinary tract urothelial carcinoma. Patients benefited from less intraoperative blood loss and a shorter hospitalization with an equivalent intermediate-term oncologic outcome compared with that of the open approach. 相似文献