全文获取类型
收费全文 | 537篇 |
免费 | 18篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 29篇 |
妇产科学 | 1篇 |
基础医学 | 54篇 |
口腔科学 | 10篇 |
临床医学 | 23篇 |
内科学 | 104篇 |
皮肤病学 | 8篇 |
神经病学 | 7篇 |
特种医学 | 83篇 |
外科学 | 54篇 |
综合类 | 122篇 |
预防医学 | 15篇 |
眼科学 | 2篇 |
药学 | 12篇 |
肿瘤学 | 33篇 |
出版年
2021年 | 26篇 |
2020年 | 1篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 10篇 |
2014年 | 6篇 |
2013年 | 7篇 |
2012年 | 8篇 |
2011年 | 7篇 |
2010年 | 25篇 |
2009年 | 21篇 |
2008年 | 20篇 |
2007年 | 14篇 |
2006年 | 26篇 |
2005年 | 14篇 |
2004年 | 17篇 |
2003年 | 15篇 |
2002年 | 13篇 |
2001年 | 9篇 |
2000年 | 6篇 |
1999年 | 13篇 |
1998年 | 32篇 |
1997年 | 24篇 |
1996年 | 28篇 |
1995年 | 16篇 |
1994年 | 31篇 |
1993年 | 10篇 |
1992年 | 6篇 |
1991年 | 1篇 |
1990年 | 7篇 |
1989年 | 12篇 |
1988年 | 15篇 |
1987年 | 16篇 |
1986年 | 14篇 |
1985年 | 13篇 |
1984年 | 9篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1980年 | 8篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1961年 | 1篇 |
排序方式: 共有558条查询结果,搜索用时 62 毫秒
31.
绝经后女性类风湿关节炎患者骨密度变化影响因素分析 总被引:2,自引:0,他引:2
目的探讨绝经后女性类风湿关节炎(RA)患者发生骨质疏松(OP)的原因。方法收集63例绝经后女性RA患者一般临床资料、疾病活动相关指标、手足X线资料,并同时测量患者7个部位的骨密度。结果23例患者(36.5%)有至少一处检测部位表现为低骨量。前臂和桡尺骨远端的低骨密度发生率(23.8%)与OP总发生率(28.6%)无显著性差异(P>0.05)。OP的发生与疾病活动指标及糖皮质激素的使用均无相关性。多元回归分析显示绝经的年限和关节腔狭窄为低骨量发生的独立危险因素(P<0.05);而雌激素替代疗法(HRT)为低骨量发生的唯一保护因素(P<0.05),小剂量糖皮质激素对本组患者的骨密度无影响。结论OP是绝经后女性RA患者的常见并发症,绝经年限长和关节破坏严重是低骨量发生的独立危险因素,HRT是防治低骨量的保护因素。 相似文献
32.
An increase in the rate of breast-feeding is beneficial for the developing countries both with regard to economy and health (1). The nutritional and immunological superiority of breastfeeding compared to artificial feeding is universally recognized. Breast-feeding has advantages not only for the infant but also for the mother and the family unit. It has also been recognized as the most effective method of birth-spacing in developing countries (2, 3) and it has advantages for the family because of its convenience and low cost (4). 相似文献
33.
Wang WS; Fan FS; Hsieh RK; Chiou TJ; Lin JK; Lin TC; Yen CC; Liu JH; Hsu H; Chen PM 《Japanese journal of clinical oncology》1997,27(3):174-179
5-Fluorouracil in combination with leucovorin has been shown to be active
in therapeutic trials of metastatic colorectal carcinoma. In this study, we
administered these drugs to 72 patients with metastatic colorectal
carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil
were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and
leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36
patients with or without prior 5-fluorouracil treatment received
5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous
infusion every two weeks. Clinical efficacy and toxicity were assessed by
WHO criteria. Variables were tested for relations to response and survival
by univariate and multivariate analysis. The response rate was 19.4% in
weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527).
Median survivals in the two arms were 18.4 months (weekly) and 21 months
(biweekly) respectively (P = 0.708). Gastrointestinal side effects
including nausea, vomiting, diarrhea and mucositia were the major
toxicities of these regimens. By multivariate analysis, the only factor to
influence response rate was the site of metastases (P = 0.009). The only
factor to affect survival was performance status of the patient (P =
0.0001). We concluded that the two 5-fluorouracil based regimens are
well-tolerated and shown to have a response rate comparable with previous
reports of similar regimens in patients with metastatic colorectal cancer.
Only liver metastases seemed to have a better response to therapy.
Performance status is the most important prognostic factor in patients with
metastatic colorectal cancer.
相似文献
34.
Wang WS; Liu JH; Chiou TJ; Hsieh RK; Yen CC; Chen PM 《Japanese journal of clinical oncology》1997,27(3):180-184
A 28-year-old woman was admitted to our Hospital with a chief complaint of
progressive gingival swelling and loosening of teeth over about a year.
According to past history, she had received total thyroidectomy 2 years
previously due to thyromegaly. The thyroidectomy specimen was at first
interpreted as 'poorly differentiated carcinoma of the thyroid'. One year
ago, she began to be aware of gingival swelling and loosening of teeth. A
gum biopsy was taken and the pathologic features were similar to her
'thyroid carcinoma'. Subsequent investigations, including
immunohistochemical stain, showed the gum was heavily infiltrated with
histiocyte-like Langerhans' cells which were positive for S-100 protein.
Ultrastructural examination of the cells under electron microscope revealed
many typical intra-cytoplasmic Birbeck granules. Langerhans' cell
histiocytosis was diagnosed. Langerhans' cell histiocytosis with thyroid
involvement is extremely rare and may run a relatively indolent course.
Even on a retrospective examination, it may easily be confused with poorly
differentiated carcinoma of the thyroid. We suspect that this error may
have been made on other occasions and that the occurrence of this condition
may be underreported.
相似文献
35.
M-mode echocardiographic findings were compared between sickle cell anemic and healthy children. Patients were composed of two groups; Group 1: mild group with no crises, no blood transfusions at the ages of 5.0 to 13.0, total of 12 children; Group 2: severe group, with frequent crises with requirement of blood transfusions at the ages of 3.0 to 13.0 years, total of 18 children. Control group was composed of 12 healthy children aged 5.0 to 13.0. When M-mode echocardiographic findings were compared, important findings were as follows: Mean left atrium dimension was increased both in the mild and severe groups (P < 0.001) compared with controls. This finding also supports the increase in the left ventricle end-diastolic dimension in both the severe and mild groups as compared with controls (P < 0.001). The increase in end-diastolic left ventricle dimension could be due to anemia present in the patients, but there was no difference between the two patient groups. Posterior left ventricle thickness and left ventricle mass was increased in both the mild and severe groups compared with controls (P < 0.001, P < 0.05), respectively. Left ventricular fractional shortening was more or less the same with controls. In spite of left ventricular volume load and dilatation, left ventricular contraction was good and systolic function was normal, and there was no correlation between the ECHO findings and hematological indices. 相似文献
36.
Exchange transfusion in neutropenic septicemic neonates: effect on granulocyte functions 总被引:1,自引:0,他引:1
NB Mathur BKM Subramanian VK Sharma RK Puri 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(12):939-943
Depletion neutropenia caused by overwhelming bacterial infection is associated with fatal outcome and is an objective indicator of the severity of sepsis. Studies on controlled evaluation of exchange transfusion in the management of severe neonatal sepsis have not considered neutropenia as an inclusion critcrion, and randomized, controlled trials on evaluation of ncutrophil functions after exchange transfusion are scarce. This prompted us to carry out the present study. Septicemic neonates were enrolled if they had neutropenia and were randomized to undergo exchange transfusion (study group, n = 20) or not (controls, n= 10). Granulocyte functions were assessed using the nitro blue tetrazolium (NBT) reduction test and the staphylococcicidal index. Blood was drawn for granulocyte function tests once from controls and donors, and before, immediately after and 6 h after exchange transfusion in the study group. Mortality was 35% in the study group and 70% in controls. Gram-negative organisms accounted for 80%, in the study group and 90% in controls. Mean total leukocyte count and neutrophil count increased significantly immediately after exchange transfusion and 6 h later. Absolute band count decreased significantly immediately after exchange transfusion and incrcased 6 h later. NBT reduction in septicemic neonates in the study group, as wclras in controls. was significantly decreascd as compared to donor cells. NBT reduction improved significantly immediately after exchange transfusion and 6 h later. The valucs of the perccntage of viable staphylococci recovered from neutrophils also improved significantly immediately after exchange transfusion and 6 h later. We conclude that exchange transfusion with fresh whole blood in severe neonatal septicemia with neutropenia improves survival, increases the neutrophil count and cnhances neutrophil function. 相似文献
37.
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
38.
39.
Muscular sufficiency, serum protein, enzymes and bioenergetic studies (31-phosphorus magnetic resonance spectroscopy) in chronic malnutrition 总被引:2,自引:0,他引:2
Muscle sufficiency was significantly lower in 1336 children with chronic malnutrition of moderate to severe degree. Eighteen children with a chronic moderate degree of malnutrition and 8 well-nourished, age-matched controls were selected for biochemical and 31-phosphorus magnetic resonance spectroscopy (31 -P MRS) studies. The results showed that: (a) serum total protein, albumin, iron, calcium and inorganic phosphate were similar in both groups; (b) serum enzyme levels were significantly increased in the malnourished group; (c) 31-P MRS showed significantly higher means for total ATP, β-ATP, a-ATP and inorganic phosphate for the malnourished compared to the control group. In chronic malnutrition, proteins are maintained by degradation in muscle resulting in release of amino acids and enzymes. 31-P MRS studies showing increases in total ATP, β-ATP and inorganic phosphate and a decrease in phosphocreatine suggest that ATP is maintained at the cost of phosphocreatine. 相似文献
40.
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