全文获取类型
收费全文 | 217篇 |
免费 | 14篇 |
国内免费 | 4篇 |
专业分类
儿科学 | 22篇 |
妇产科学 | 2篇 |
基础医学 | 18篇 |
口腔科学 | 2篇 |
临床医学 | 16篇 |
内科学 | 46篇 |
皮肤病学 | 2篇 |
神经病学 | 5篇 |
特种医学 | 83篇 |
外科学 | 14篇 |
综合类 | 5篇 |
预防医学 | 4篇 |
药学 | 9篇 |
肿瘤学 | 7篇 |
出版年
2021年 | 1篇 |
2020年 | 1篇 |
2019年 | 6篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 6篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2010年 | 5篇 |
2009年 | 9篇 |
2008年 | 1篇 |
2007年 | 5篇 |
2006年 | 3篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 15篇 |
1997年 | 14篇 |
1996年 | 16篇 |
1995年 | 6篇 |
1994年 | 9篇 |
1993年 | 11篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 5篇 |
1989年 | 12篇 |
1988年 | 10篇 |
1987年 | 9篇 |
1986年 | 9篇 |
1985年 | 11篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 9篇 |
1981年 | 1篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1960年 | 1篇 |
1939年 | 1篇 |
1937年 | 1篇 |
排序方式: 共有235条查询结果,搜索用时 879 毫秒
41.
Cholescintigrams of 17 amebic liver abscesses (ALAs) in 13 patients were studied retrospectively. Rim enhancement around a photopenic defect was seen in nine (53%) of 17 abscesses. Most of the ALAs were solitary, in the right lobe, and ovoid. All were contiguous with the liver capsule. Ultrasonograms, obtained in 11 of 13 patients, showed the ALAs to be predominantly hypoechoic, with low-level echoes on high-gain settings. No sonographic finding could be identified to correlate with rim enhancement. Cholescintigraphic rim enhancement may allow early diagnosis of ALA in patients with right-upper-quadrant pain, facilitating early institution of specific therapy while definitive serologic confirmation of ALA is awaited. 相似文献
42.
Multicystic dysplastic kidney: observations of contralateral disease in the fetal population 总被引:2,自引:0,他引:2
To evaluate multicystic dysplastic kidney (MDK) and associated contralateral renal abnormalities in the fetal population, 27 cases detected and followed in utero were reviewed retrospectively. The sonographic assessment included estimation of amniotic fluid volume and interval growth, evaluation for non-genitourinary anomalies, and postnatal follow-up study. Contralateral renal anomalies were detected in 41% of the fetuses and included obstruction of the ureteropelvic junction, renal agenesis, renal hypoplasia, and bilateral MDK. The incidences of these malformations were compared with results of earlier studies of MDK in the pediatric and adult populations. Lethal anomalies, such as bilateral MDK and MDK associated with contralateral agenesis, are common (19% and 11%, respectively) in the fetal population; obstruction of the contralateral ureteropelvic junction, a nonlethal anomaly, was seen less commonly (7%). Perinatal death from lethal abnormalities may spuriously raise the incidence of nonlethal contralateral abnormalities in the pediatric and adult populations. Contralateral mild fetal pyelectasis, found in 15% of fetuses with MDK, was not clinically significant. 相似文献
43.
Resolving duodenal-jejunal hematoma in abused children 总被引:1,自引:0,他引:1
Acute intramural duodenal-jejunal hematoma is a classical finding in the battered child syndrome. The radiographic findings of a large obstructing intramural mass associated with the "coiled-spring" appearance generally raise the question of child abuse in any patient without appropriate accidental injury. In this study the radiologic features of resolving duodenal-jejunal hematoma are detailed in five abused children. The results show that the coiled-spring appearance is an acute phenomenon associated with a well-localized intramural hematoma. In the resolving phase, localized mural masses in the lateral aspect of the descending duodenum and fold thickening are indications of prior intramural hemorrhage. When these radiologic features are encountered in a child with nonspecific abdominal complaints, child abuse should be suspected. Furthermore, in patients with suspected occult trauma, resolution of abdominal symptoms should not deter the radiologist from performing an upper gastrointestinal tract series, which may provide evidence of child abuse. 相似文献
44.
Plasma thyroid stimulating hormone (TSH) concentrations obtained during the first four years of treatment in 418 children with congenital hypothyroidism, identified by neonatal screening, were examined in relation to paired measurements of plasma thyroxine (n = 1945), free thyroxine (n = 836), triiodothyronine (n = 480), and free triiodothyronine (n = 231), and estimated daily dose of thyroxine at the time of blood sampling. Overall, plasma TSH was above 7 mU/l in 1280 out of 2960 samples (43%); the percentage was not related to severity of hypothyroidism at diagnosis. Mean values for thyroxine and free thyroxine, and to a lesser extent free triiodothyronine, were consistently lower in samples with TSH concentrations over 7 mU/l and this was the case in patients with either severe or less severe hypothyroidism. Raised TSH concentrations were also associated with lower mean doses of thyroxine (micrograms/kg/day) but here the mean doses of thyroxine in children with severe hypothyroidism were higher than in the children with less severe hypothyroidism. The mean dose of thyroxine associated with low/normal TSH values was highest in the first 6 months and fell progressively. Thyroxine dose was significantly related to thyroxine and free thyroxine concentrations but not to triiodothyronine and free triiodothyronine and the latter appeared to be of limited value as measures of plasma thyroid hormone status during treatment. 相似文献
45.
46.
Daniel I. Sessler Joshua A. Bloomstone Solomon Aronson Colin Berry Tong J. Gan John A. Kellum James Plumb Monty G. Mythen Michael P.W. Grocott Mark R. Edwards Timothy E. Miller Timothy E. Miller Monty G. Mythen Michael PW. Grocott Mark R. Edwards 《British journal of anaesthesia》2019,122(5):563-574
Background
Intraoperative mortality is now rare, but death within 30 days of surgery remains surprisingly common. Perioperative myocardial infarction is associated with a remarkably high mortality. There are strong associations between hypotension and myocardial injury, myocardial infarction, renal injury, and death. Perioperative arterial blood pressure management was thus the basis of a Perioperative Quality Initiative consensus-building conference held in London in July 2017.Methods
The meeting featured a modified Delphi process in which groups addressed various aspects of perioperative arterial pressure.Results
Three consensus statements on intraoperative blood pressure were established. 1) Intraoperative mean arterial pressures below 60–70 mm Hg are associated with myocardial injury, acute kidney injury, and death. Injury is a function of hypotension severity and duration. 2) For adult non-cardiac surgical patients, there is insufficient evidence to recommend a general upper limit of arterial pressure at which therapy should be initiated, although pressures above 160 mm Hg have been associated with myocardial injury and infarction. 3) During cardiac surgery, intraoperative systolic arterial pressure above 140 mm Hg is associated with increased 30 day mortality. Injury is a function of arterial pressure severity and duration.Conclusions
There is increasing evidence that even brief durations of systolic arterial pressure <100 mm Hg and mean arterial pressure <60–70 mm Hg are harmful during non-cardiac surgery. 相似文献48.
Detecting fetomaternal hemorrhage: a comparison of five methods 总被引:3,自引:0,他引:3
KM Bayliss ; BD Kueck ; ST Johnson ; JT Fueger ; PW McFadden ; D Mikulski ; JL Gottschall 《Transfusion》1991,31(4):303-307
Appropriate postpartum administration of Rh immune globulin relies on sensitive detection and accurate quantitation of fetomaternal hemorrhage (FMH). Recently, the microscopic Du test (micro Du) enhanced with polyethylene glycol (PEG Du) and flow cytometry (FC) have been advocated for this purpose. Three qualitative methods (micro Du, rosette test, and PEG Du) and two quantitative methods (acid elution and FC) for assessing FMH were evaluated with particular attention given to PEG Du and FC. In vitro studies comprised 10 series of dilutions of D+ cord cells in D- adult cells to yield D+ cell concentrations of 0.06, 0.12, 0.25, 0.50, 0.75, 1.0, and 2.0 percent. Additionally, 26 postpartum samples were tested. Of the qualitative techniques, the micro Du test was the least sensitive with 20 percent false-negative results occurring at 0.5 percent fetal cells. The PEG Du test was only slightly more sensitive and offered no clinical advantage. The rosette test was the most sensitive, consistently detecting fetal cells at concentrations of 0.25 percent or greater. FC and acid elution showed similar results, with good correlation obtained between measured and expected quantities of fetal cells (r = 0.99 and 0.96, respectively). One of 26 postpartum samples was positive by all screening techniques; acid elution and FC detected 0.3-percent concentrations of fetal cells and 0.17-percent concentrations of D+ cells, respectively. Although acid elution is a more commonly used method for quantitating FMH, FC offers an acceptable alternative that is capable of analyzing large numbers of cells with objectivity and reproducibility. 相似文献
49.
van der Linden PW; Hack CE; Eerenberg AJ; Struyvenberg A; van der Zwan JK 《Blood》1993,82(6):1732-1739
A postulated role of the contact system in anaphylactic reactions to insect stings was investigated. During prospective, in-hospital sting challenge, we collected serial blood samples from five normal volunteers and 16 patients with a history of insect-sting anaphylaxis. Activation of the contact system was assessed by measuring plasma levels of factor XIIa-C1-inhibitor and kallikrein-C1-inhibitor complexes as well as those of cleaved high molecular weight kininogen (HK). In addition, antigenic levels of (pre)kallikrein, factor XII, and HK were measured. No significant changes in contact system parameters were observed in any of the five volunteers or the four patients who did not develop an anaphylactic reaction after sting challenge. In contrast, significant changes in contact system parameters occurred in 7 of the 12 patients with anaphylactic symptoms after challenge. Peak levels of either C1-inhibitor complex were found 5 minutes after the onset of anaphylactic symptoms. The increase in C1-inhibitor was most pronounced in the 4 patients with angioedema, 2 of which also developed shock. However, activation of HK was observed in all four patients with angioedema, the two patients with shock but no angioedema, as well as in 1 of the remaining 6 patients with anaphylactic symptoms other than angioedema or shock. Thus, activation products of the contact system may be involved in the pathogenesis of angioedema and shock in insect- sting anaphylaxis. 相似文献
50.
In the human promyelocytic cell line HL60, we observed both a strong procoagulant activity (PCA) on the cell membrane and proteolytic activity in the lysate of these cells. Because these cell-line cells are susceptible to differentiation to either a more mature granulocytic or monocytic form, we were able to study the hypothesis that the combination of PCA and proteolytic activity is confined to the promyelocyte. This may explain the severe coagulopathy seen in patients with acute promyelocytic leukemia. Cell differentiation in a myeloid direction induced by retinoic acid or DMSO led to a diminished PCA, while not affecting the fibrinolytic activity. On the other hand, monocytic differentiation obtained by culturing the cells in the presence of 1; 25 dihydroxy vitamin D3 led to the complete disappearance of the proteolytic activity of the cell lysate, although the procoagulant activity was still present. Furthermore, we found that the elastase activity almost disappeared after monocytic differentiation. We also studied the PCA, proteolytic activity, and elastase activity of blast cells of patients with acute myeloid leukemia. Only in patients with acute promyelocytic leukemia did we observe both a strong PCA and fibrinolytic activity. This supports our hypothesis that the combination of these activities is unique to the promyelocyte and may explain the observed bleeding complications in patients with acute promyelocytic leukemia. 相似文献