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   489篇
  免费   27篇
  国内免费   4篇
耳鼻咽喉   3篇
儿科学   39篇
妇产科学   5篇
基础医学   29篇
口腔科学   10篇
临床医学   33篇
内科学   86篇
皮肤病学   9篇
神经病学   7篇
特种医学   90篇
外科学   57篇
综合类   69篇
预防医学   20篇
眼科学   11篇
药学   20篇
中国医学   2篇
肿瘤学   30篇
  2022年   6篇
  2021年   7篇
  2020年   10篇
  2019年   6篇
  2018年   11篇
  2017年   6篇
  2016年   8篇
  2015年   17篇
  2014年   12篇
  2013年   13篇
  2012年   23篇
  2011年   22篇
  2010年   24篇
  2009年   19篇
  2008年   12篇
  2007年   13篇
  2006年   18篇
  2005年   22篇
  2004年   6篇
  2003年   5篇
  2002年   15篇
  2001年   10篇
  2000年   6篇
  1999年   11篇
  1998年   29篇
  1997年   24篇
  1996年   18篇
  1995年   15篇
  1994年   12篇
  1993年   9篇
  1992年   4篇
  1990年   1篇
  1989年   14篇
  1988年   11篇
  1987年   15篇
  1986年   12篇
  1985年   5篇
  1984年   8篇
  1983年   7篇
  1982年   6篇
  1981年   7篇
  1980年   7篇
  1978年   1篇
  1977年   1篇
  1976年   3篇
  1975年   8篇
  1969年   1篇
排序方式: 共有520条查询结果,搜索用时 46 毫秒
21.
Horne  MK d; Rosse  WF; Flickinger  EG; Saltzman  HA 《Blood》1975,45(3):365-375
The "early-labeled" peak (ELP) of 14CO excretion following injection of glycine-2-14C was used to study erythropoiesis in a patient with sideroblastic anemia and in four subjects with myeloproliferative disorders. The ELP was greatly enlarged in all patients, as compared with a normal volunteer. The contour of the peaks from the hematologically abnormal subjects suggested the presence of increased erythroid heme degradation. In the patient with sideroblastic anemia, all hours of the early peak were significantly reduced after transfusion. This was interpreted to mean that even the earliest or "nonerythroid" phase of the peak is influenced by erythropoietic activity, at least under conditions of erythropoietic stress.  相似文献   
22.
Leonard  JP; Quinto  CM; Kozitza  MK; Neben  TY; Goldman  SJ 《Blood》1994,83(6):1499-1506
Interleukin-11 (IL-11) is a novel multifunctional hematopoietic cytokine capable of stimulating cells of the myeloid, lymphoid, erythroid, and megakaryocytic lineages in vitro. We have tested the pleiotropic properties of this cytokine on the hematopoietic recovery of mice after a combined regimen of sublethal irradiation and carboplatin administration. This regimen results in severe myelosuppression, characterized by a prolonged period of thrombocytopenia and severe anemia. Administration of recombinant human IL-11 (rhIL-11; 250 micrograms/kg/d) had multilineage effects on bone marrow and spleen hematopoietic activity, increasing the number of megakaryocyte, erythroid, granulocyte, and macrophage progenitors compared with the vehicle-treated controls. This was reflected in the peripheral circulation by a reduction of both the platelet and hematocrit nadirs and a significantly reduced period of thrombocytopenia and anemia in the rhIL-11-treated mice. The results from this study support the broad spectrum of biologic activities that have been attributed to rhIL-11 in vitro and suggest that this cytokine may be an effective agent in the treatment of myelosuppression associated with cancer chemotherapy and bone marrow transplantation.  相似文献   
23.
Porter  CD; Parkar  MH; Levinsky  RJ; Collins  MK; Kinnon  C 《Blood》1993,82(7):2196-2202
Chronic granulomatous disease (CGD) is an inherited immunodeficiency resulting from the inability of an individual's phagocytes to produce superoxide anions because of defective NADPH oxidase. The disease may be treated by bone marrow transplantation and as such is a candidate for somatic gene therapy. Two thirds of patients have defects in an X- linked gene (X-CGD) encoding gp91-phox, the large subunit of the membrane cytochrome b-245 component of NADPH oxidase. Epstein-Barr virus-transformed B-cell lines from patients with CGD provide a model system for the disease. We have used retrovirus-mediated expression of gp91-phox to reconstitute functionally NADPH oxidase activity in B-cell lines from three unrelated patients with X-CGD. The protein is glycosylated and membrane associated, and the reconstituted oxidase is appropriately activated via protein kinase C. The kinetics of superoxide production by such reconstituted cells is similar to that of normal B-cell lines. These data show the potential of gene therapy for this disease.  相似文献   
24.

Purpose

Evaluation of the psychometric properties of a cross-culturally adapted questionnaire, the Core Outcome Measurement Index for neck pain (COMI-neck).

Methods

The COMI-neck was cross-culturally adapted for the Italian language using established procedures. The following psychometric properties of the instrument were then assessed in patients with chronic neck pain undergoing rehabilitation: test–retest reliability (intraclass correlation coefficient, ICC); construct validity by comparing COMI-neck with the Neck Pain and Disability Scale, a numerical pain rating scale, and the EuroQol-Five Dimension (Pearson’s correlations); and responsiveness by means of Standardized Response Mean (SRM), unpaired t tests, and Receiver Operating Characteristics (ROC) curves.

Results

The questionnaire was completed by 103 subjects. The COMI-neck summary score displayed no relevant floor or ceiling effects. Test–retest reliability was excellent (ICC = 0.87). With one exception (symptom-specific well-being), the individual COMI items and the COMI summary score correlated to the expected extent with the scores of the reference questionnaires (r = 0.40–0.80). The mean change scores for the Italian COMI-neck differed significantly between patients with a good global outcome and those with a poor outcome (p = 0.002); SRM for the good outcome group was 1.23, and for the poor outcome group 0.40. ROC analysis revealed an area under the curve of 0.73 (95 % CI: 0.62–0.85).

Conclusions

This study provides evidence that the Italian version of the COMI-neck is a valid and responsive questionnaire in the population of patients examined. Its use is recommended for clinical and research purposes.  相似文献   
25.
26.
Chronic right lower quadrant pain is a common clinical entity and continues to remain a diagnostic and therapeutic problem. Laparoscopy is changing the view regarding exploration in patients with chronic right lower quadrant pain. Of recent, chronic or recurrent right lower quadrant pain is an entity that has generated much interest, hence this study has been undertaken. To study the role of elective laparoscopic appendicectomy for chronic or recurrent right lower quadrant pain. To study the relationship between clinical improvement and histopathological findings of removed appendix. Forty three cases of chronic right lower quadrant pain, who met the inclusion criteria, were included in the clinical study. Three cases were excluded during initial diagnostic laparoscopy because of ovarian cyst. Laparoscopic appendicectomy was performed in 40 cases. In our study amongst 40 (100 %) patients, 36(90 %) patients were relieved of pain completely. Only 4(10 %) patients continued to have persistent right lower quadrant pain. Duration of follow up was 6 months. Postoperative pain scores favour appendicectomy (p < 0.005). There was no association between postoperative pain scores and histopathology findings. There was no mortality in our study. Persistent or recurrent right lower quadrant pain can be treated successfully by elective laparoscopic appendicectomy in properly selected cases. Laparoscopic appendectomy is a feasible and safe procedure. Histopathology of the removed appendix does not contribute to the diagnosis.  相似文献   
27.
Objective: It has been shown that adiponectin serves as an insulin-sensitizing adipokine. Serum concentrations of adiponectin are low in children with obesity, and increase with fat mass loss, indicating that adiponectin can serve as a biomarker. Since the prevalence of overweight and obesity is increased in children with congenital adrenal hyperplasia (CAH), our study aimed to evaluate serum levels of adiponectin in a cohort of CAH children and adolescents, and their associations with clinical parameters such as chronological age (CA), body mass index (BMI), Tanner stage (TS), medication and metabolic control.
Patients and methods: We studied 51 patients, aged between 5.6 and 19.6 years (median 11.8; 30 females, 21 males), cross-sectionally. All patients had genetically confirmed CAH and received standard steroid substitution therapy. Adiponectin was measured by an enzyme linked immunoassay. Since BMI SDS of the CAH cohort were significantly higher compared to the reference population, we built matched pairs with healthy Caucasian subjects from a normal representative cohort for sex, Tanner stage, chronologic age and BMI.
Results: Adiponectin concentrations were significantly higher in CAH patients (median 11 μg/L) compared to the matched controls (6.7 μg/L, p < 0.0001). Correlation analyses in CAH patients revealed a significant inverse relationship between adiponectin and CA, TS, BMI, serum DHEAS and serum testosterone, but no correlation with hydrocortisone and fludrocortisone dosage.
Conclusion: Currently, the importance of the elevated adiponectin concentrations in CAH children for risk assessment is not clear. However, our data imply that besides adequate metabolic control of glucocorticoid substitution, a long-term follow-up of other metabolic markers of insulin resistance should be conducted in CAH patients.  相似文献   
28.
We describe the case of a 40‐year‐old woman who presented with a pararenal hyaline‐vascular type Castleman’s disease that had an arterial supply from the renal artery and a draining vein as showed by multidetector CT. Identification of the renal artery relationship to the feeding vessel of the mass is critical to prevent potential surgical complications.  相似文献   
29.
In a case-control study to understand the risk factors for development of life-threatening dehydration, a total of 379 children comprising 243 cases (moderate or severe dehydration) and 136 controls (non or mild dehydration) up to 2 years of age suffering from acute watery diarrhoea were studied. By univariate analysis, the presence of vibrios in stool, withdrawal of breast feeding during diarrhoea, not giving fluids, including oral rehydration solution (ORS), during diarrhoea, frequent purging (> 8/ day), vomiting (> 2/day) and undernutrition were identified as risk factors. However, by multivariate analysis after controlling for confounders, withdrawal of breast feeding during diarrhoea (odds ratio (OR) = 6.8, p < 0.00001) and not giving ORS during diarrhoea (OR = 2.1, p < 0.006) were identified as significant risk factors. The confounding variables which also contributed significantly to increasing the risk were age (≤ 12 months; OR = 2.7, p = 0.001), frequent purging (> 8/day; OR = 4.1, p < 0.00001), vomiting (> 2/day; OR = 2.4, p = 0.001) and severe undernutrition (%median <60 weight-for-age of Indian Academy of Paediatrics classification; OR = 3.1, p = 0.001). We feel that these findings will be useful for Global and National Diarrhoeal Diseases Control Programmes for formulating intervention strategies for preventing death due to diarrhoeal dehydration.  相似文献   
30.
At the Department of Radiation Oncology, Westmead Hospital, between 1980 and 2000, 60 patients with squamous cell carcinoma of anal canal or margin (including 15 with Stage IIIA or IIIB) were treated radically; 55 received chemoradiation (89% were prescribed mitomycin C and 5‐fluorouracil). Five‐year overall survival was 64% (95% confidence interval (CI): 48–79%), with a median survival of 9.75 years (median follow up 5.6 years, range 5 months to 22.5 years). Ten patients have died of disease. At 2 years the local control rate was 86%, and colostomy‐free survival was 83%. Relapse after 2 years was uncommon. Tumour size was the main factor driving outcomes, especially survival. Patients with larger tumours (T > 4 cm) had a hazard ratio for survival of 5.7 (95% CI: 1.8–17). Fourteen (24%) patients experienced treatment interruptions as a result of acute toxicity, including one death from neutropoenic sepsis. Seven (12%) patients, in total, experienced one or more late toxicities, grade 3 or above, including four women (all postmenopausal) who developed a radiation‐induced bone injury. Most patients with anal cancer can expect to retain a functional sphincter after chemoradiation/radiation. Further studies are in progress to determine the optimal chemoradiation protocol.  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