首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   10801篇
  免费   734篇
  国内免费   64篇
耳鼻咽喉   62篇
儿科学   247篇
妇产科学   281篇
基础医学   1538篇
口腔科学   396篇
临床医学   991篇
内科学   2214篇
皮肤病学   195篇
神经病学   1326篇
特种医学   321篇
外科学   1252篇
综合类   25篇
现状与发展   1篇
一般理论   8篇
预防医学   967篇
眼科学   121篇
药学   711篇
中国医学   49篇
肿瘤学   894篇
  2024年   11篇
  2023年   115篇
  2022年   198篇
  2021年   424篇
  2020年   257篇
  2019年   393篇
  2018年   429篇
  2017年   340篇
  2016年   394篇
  2015年   372篇
  2014年   465篇
  2013年   605篇
  2012年   874篇
  2011年   851篇
  2010年   455篇
  2009年   431篇
  2008年   679篇
  2007年   643篇
  2006年   634篇
  2005年   577篇
  2004年   541篇
  2003年   476篇
  2002年   386篇
  2001年   116篇
  2000年   86篇
  1999年   111篇
  1998年   59篇
  1997年   70篇
  1996年   39篇
  1995年   34篇
  1994年   31篇
  1993年   24篇
  1992年   56篇
  1991年   66篇
  1990年   35篇
  1989年   42篇
  1988年   36篇
  1987年   35篇
  1986年   27篇
  1985年   27篇
  1984年   25篇
  1983年   8篇
  1982年   15篇
  1981年   9篇
  1980年   8篇
  1979年   11篇
  1977年   11篇
  1974年   13篇
  1973年   10篇
  1971年   8篇
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
941.

Background

Clinical and psychosocial outcomes of a multimodal surgical approach for chronic intestinal pseudo-obstruction were analyzed in 24 patients who were followed over a 2- to 12-year period in a single center after surgery or intestinal/multivisceral transplant (CTx).

Methods

The main reasons for surgery were sub-occlusion in surgery and parenteral nutrition–related irreversible complications with chronic intestinal failure in CTx.

Results

At the end of follow-up (February 2015), 45.5% of CTx patients were alive: after transplantation, improvement in intestinal function was observed including a tendency toward recovery of oral diet (81.8%) with reduced parenteral nutrition support (36.4%) in the face of significant mortality rates and financial costs (mean, 202.000 euros), frequent hospitalization (mean, 8.8/re-admissions/patient), as well as limited effects on pain or physical wellness.

Conclusions

Through psychological tests, transplant recipients perceived a significant improvement of mental health and emotional state, showing that emotional factors were more affected than were functional/cognitive impairment and social interaction.  相似文献   
942.

Background

Obesity and metabolic surgery is known to improve chronic inflammatory status. Whether improvement is related to anatomical changes or weight loss is still to debate.

Objective

The aim of this clinical trial is to compare the different bariatric procedures sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and One-anastomosis gastric bypass (OAGB), pertaining to their effects on inflammation markers.

Methods

Patients who underwent SG, RYGB, or OAGB as a primary treatment for severe obesity were included. The data collected preoperatively (T0) and 1, 3, and 6 (T6) months after surgery included gender, weight, comorbidities and toxic habits at baseline, body mass index (BMI), waist circumference, total body weight loss in % (TBWL), leukocyte count in ×?103/μl, C-reactive protein (CRP) in mg/l, HbA1c in %, aspartate transaminase in U/l, alanine transaminase in U/l, gamma-glutamyltransferase in U/l, bilirubin in mg/dl, cholesterol in mg/dl, and triglycerides in mg/dl.

Results

Four hundred sixty-eight patients were included. Drop-out rate was 25.8% at T6. Preoperatively the mean value of leukocytes and CRP was 7.4?×?103/μl?±?2 and 10.5 mg/l?±?8.1. At T6, mean value of leukocytes and CRP was 7.1?×?103/μl?±?1.9 (p?=?0.075) and 7.2 mg/l?±?9.5 (p?<?0.001). TBWL % at T6 was 24.2?±?7.6 in the SG, 25.8?±?5.9 in the RYGB and 25.5?±?4.6 in the OAGB group. Comparing SG, RYGB, and OAGB in relation to leukocyte count and CRP no significant difference was seen between the groups.

Conclusion

CRP but not leukocyte count decreased after all three bariatric procedures but without any significance between the three groups. Surgically induced weight loss and not anatomical changes might play an important role for improvement in chronic inflammation.

Trial Registration

The National Clinical Trials number was NCT02697695 (https://clinicaltrials.gov/ct2/show/NCT02697695).
  相似文献   
943.
Several new quinolone derivatives were investigated for their influence on human lymphocyte blastogenesis and gamma-interferon production following concanavalin A stimulation. All the antimicrobials induced inhibition of lymphocyte DNA synthesis. The gamma-interferon measurements showed that nalidixic acid and norfloxacin have a negative influence on lymphokine production and release.  相似文献   
944.
Irving SY  Simone SD  Hicks FW  Verger JT 《AACN clinical issues》2000,11(4):541-58; quiz 637-8
The requirements of growth and organ development create a challenge in nutrition management for the pediatric patient. The stress of critical illness further complicates the delivery of adequate nutrients. Enteral feeding has several advantages over parenteral nutrition (PN), which include preservation of the gastrointestinal mucosa and decreasing the occurrence of sepsis related to bacterial translocation. Although feeding through the gastrointestinal tract is the preferred route for nutritional management, there are specific instances when PN as adjunctive or sole therapy is necessary to meet nutritional needs. With meticulous attention to fluid, caloric, protein, and fat requirements along with monitoring the metabolic status of the patient, it is possible to provide full nutritional support for the critically ill child within 24 to 48 hours of hospital admission.  相似文献   
945.
946.
947.
BACKGROUND: There is currently no international reference preparation for IgG subclass (IgGSc) quantification. This situation has led to calibration differences among assays and a variety of reference interval values with consequential difficulties in comparing results. We therefore evaluated IgGSc concentrations in Certified Reference Material 470 (CRM 470). METHODS: Pure, polyclonal IgG1, -2, -3, and -4 were prepared from a large serum pool for use as primary standards. The IgG mass in each preparation was calculated from amino-acid analysis data. IgGSc concentrations were assessed in CRM 470 by nephelometry with modern analytical techniques, using these reference preparations. Subsequently, IgGSc concentrations were measured in 380 healthy individuals (250 males and 130 females), and age-dependent reference intervals were established. RESULTS: IgGSc concentrations in CRM 470 were as follows: IgG1, 5028 mg/L; IgG2, 3418 mg/L; IgG3, 579 mg/L, and IgG4, 381 mg/L, with a total IgG concentration of 9406 mg/L, 2.83% below the certified total IgG value of 9680 mg/L. Age-dependent percentile curves for the four IgGSc were constructed using a Box-Cox transformation. Maximum median values were as follows: IgG1, 6.02 g/L at 11 years; IgG2, 3.45 g/L at 31 years; IgG3, 0.63 g/L at 17 years; and IgG4, 0.48 g/L at 14 years. No significant sex-related differences were observed. CONCLUSIONS: The correlation between the summation of individual IgGSc and separate measurements of total IgG concentrations was good and supports the accuracy of the results. The results are based on The Binding Site assays and should not be considered appropriate for other assays unless so demonstrated.  相似文献   
948.
949.
Background  Chronic heart failure (CHF) is a widespread disease with severe quality of life impairment and a poor prognosis. Beta-blockers are the mainstay of CHF therapy; yet they are under-prescribed and under-dosed in clinical practice. This is particularly evident in elderly patients, which may be due to a fear of side-effects or intolerance. Beta-blockers have further not been adequately tested in patients with diastolic CHF, which is particularly common in elderly patients. Finally, comparative data on the use of different beta-blockers in patients with CHF is scarce. Aim  To compare the tolerance of bisoprolol and carvedilol in elderly patients with CHF. Methods  CIBIS-ELD is an investigator-initiated, multi-centre, 1:1 randomised, double-blind, phase III trial comparing bisoprolol and carvedilol in patients ≥65 years with systolic or diastolic CHF. Recruitment started in April 2005 and is anticipated to be completed by April 2008 with at least 800 patients enrolled. Perspective  This is the first large scale head to head beta-blockers trial in an elderly population with CHF. Besides determining which of two standard beta-blockers is best tolerated in elderly patients with systolic or diastolic CHF, we expect to gain further insight into the treatment of the particular population of patients with diastolic CHF. This trial was supported by the Competence Network of Heart Failure funded by the Federal Ministry of Education and Research (BMBF, project number 01GI0205) and is registered with number ISRCTN34827306 at .  相似文献   
950.

Background

Adrenal cavernous hemangiomas are very rare benign tumors that usually present as incidental findings on abdominal imaging. Preoperative differential diagnosis from other benign or malignant adrenal neoplasms may be challenging.

Case presentation

A 70-year old man was referred for an 8-cm abdominal mass incidentally discovered on a contrast-enhanced computed tomography (CT) performed to investigate a pulmonary nodule. Biochemical tests ruled out any endocrine dysfunction and iodine 123 metaiodobenzylguanidine whole body scintiscan single-photon emission CT excluded a pheocromocitoma. Findings on magnetic resonance imaging were non-specific and the patient was elected for a left adrenalectomy. Histopathological diagnosis revealed a cavernous hemangioma. A portion of the resected tissue was tested for drug sensitivity to mitotane, doxorubicin, and sunitinib.

Conclusions

Adrenal hemangioma is a rare disease but should be included in the differential diagnosis of adrenal tumors. The surgical resection is generally required to exclude malignant disease, resolve pressure-related symptoms, and prevent retroperitoneal hemorrhage. Although specific features in diagnostic imaging are often lacking, if the diagnosis is established preoperatively a laparoscopic adrenalectomy can be performed due to the benign nature of the lesion. Doxorubicin and sunitinib were both capable of reducing primary culture cell viability, this suggest that similar drugs may be useful in the medical treatment of adrenal hemangiomas.
  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号