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   426篇
  免费   16篇
耳鼻咽喉   4篇
儿科学   19篇
妇产科学   82篇
基础医学   66篇
口腔科学   6篇
临床医学   26篇
内科学   55篇
皮肤病学   3篇
神经病学   96篇
特种医学   4篇
外科学   36篇
预防医学   9篇
眼科学   1篇
药学   27篇
肿瘤学   8篇
  2024年   1篇
  2023年   3篇
  2022年   4篇
  2021年   10篇
  2020年   6篇
  2019年   6篇
  2018年   10篇
  2017年   4篇
  2016年   9篇
  2015年   11篇
  2014年   29篇
  2013年   40篇
  2012年   29篇
  2011年   28篇
  2010年   14篇
  2009年   8篇
  2008年   16篇
  2007年   17篇
  2006年   32篇
  2005年   24篇
  2004年   22篇
  2003年   13篇
  2002年   23篇
  2001年   9篇
  2000年   15篇
  1999年   16篇
  1998年   6篇
  1997年   3篇
  1996年   3篇
  1995年   2篇
  1994年   2篇
  1993年   1篇
  1992年   1篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1986年   1篇
  1985年   2篇
  1982年   1篇
  1975年   3篇
  1974年   1篇
  1973年   5篇
  1972年   1篇
  1971年   3篇
  1970年   1篇
  1969年   1篇
  1968年   2篇
  1967年   1篇
排序方式: 共有442条查询结果,搜索用时 140 毫秒
1.
BACKGROUND: To investigate the degree of systemic inflammation, as reflected by serum C-reactive protein (CRP) levels, associated with controlled ovarian hyperstimulation (COH) with human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) agonist for the induction of final follicular maturation. DESIGN: Prospective, observational study. SETTING: An in vitro fertilization (IVF) unit of an academic medical center. PATIENTS: Twenty-four women undergoing COH and IVF with the flexible GnRH antagonist protocol were prospectively assigned to receive hCG or GnRH agonist for the induction of final follicular maturation. METHODS: Blood was drawn three times during COH for measurement of sex-steroid and CRP levels: the day on which adequate suppression was obtained (Day-0); the day of or prior to administration of hCG (Day-hCG); and (3) the day of ovum pick-up (Day-OPU). Levels were compared among the three time points in the two groups. RESULTS: No between-group differences were observed in terms of patient age, gonadotropin dosage, duration of stimulation or number of oocytes retrieved. Serum CRP levels were significantly higher on Day-OPU than on Day-hCG and Day-0, but the difference was significant only in the hCG group (p<0.03 for both). The percentage change in CRP levels after hCG administration (Day-OPU vs. Day-hCG) (96%) was higher than that after GnRH administration (23%). CONCLUSION: Administration of GnRH agonist in patients undergoing COH for IVF yields a lesser degree of systemic inflammation, as reflected by CRP levels, than hCG.  相似文献   
2.
Status dystonicus (SD) is a life threatening disorder that develops in patients with both primary and secondary dystonia, characterized by acute worsening of symptoms with generalized and severe muscle contractions. To date, no information is available on the best way to treat this disorder. We review the previously described cases of SD and two new cases are reported, one of which occurring in a child with static encephalopathy, and the other one in a patient with pantothenate kinase-associated neurodegeneration. Both patients were admitted to an intensive care unit and treated with midazolam and propofol. This approach proved to be useful in the former while the progressive nature of the dystonia of the second patient required the combination of intrathecal baclofen infusion and bilateral pallidal deep brain stimulation. We believe that a rapid and aggressive approach is justified to avoid the great morbidity and mortality which characterize SD. Our experience, combined with the data available in the literature, might permit to establish the best strategies in managing this rare and severe condition.  相似文献   
3.
OBJECTIVE: To assess the effects of bilateral oophorectomy on the resting ECG and whether they regress with estrogen replacement therapy. STUDY DESIGN: Twenty-six premenopausal and 15 postmenopausal women were enrolled in the present study. All women had undergone hysterectomy and bilateral ovariectomy. All women underwent 12-lead ECG on admission to hospital. A second ECG was recorded 20-25 days after surgery. After this second ECG, premenopausal women were randomly divided into two groups. The women of Group A (n=14) received transdermal ethinyl estradiol (EE). The women of Group B (n=12) did not receive any therapy. A third ECG was performed in both groups 30-35 days after randomization. RESULTS: Bilateral oophorectomy did not induce any significant modifications in the ECG parameters of the postmenopausal women whereas in the premenopausal women, we observed a significant increment in mean duration of the T wave, a significant decrease in its amplitude and significant reduction in ST depression in V2, V3, V4 and V5. The third ECG showed regression of the ECG modifications in Group A. In the women of Group B, the second and third ECGs were not substantially different, but there were statistically significant differences between the first and third ECGs. CONCLUSIONS: The results of the present study show that ovariectomy induces significant though not clinically evident modifications in resting ECG. These ECG changes are probably due to the sudden reduction in sex hormone plasma levels after ovariectomy. Administration of estradiol induced regression of the ECG modifications.  相似文献   
4.
Anti-Müllerian hormone concentrations in maternal serum during pregnancy   总被引:1,自引:0,他引:1  
BACKGROUND: In females, anti-Müllerian hormone (AMH) is expressed only by the ovary. AMH is secreted by the granulosa cells of ovarian follicles and appears to regulate early follicle development. AMH is detected in serum from women of reproductive age and its levels vary slightly with the menstrual cycle, reaching the peak value in the late follicular phase. This study investigated serum AMH levels throughout gestation and after delivery in healthy pregnant women. METHODS: This cross-sectional study recruited pregnant women and healthy non-pregnant women, 84 in total. AMH, FSH and E2 were measured in the follicular phase, in the three trimesters of pregnancy and in early puerperium. RESULTS: Estradiol and FSH levels followed the expected patterns during gestation. During the follicular phase of the menstrual cycle AMH levels were 1.9 +/- 0.5 ng/ml. In the three trimesters of pregnancy and in early puerperium AMH levels were: 2.1 +/- 0.56, 2.4 +/- 0.64, 1.95 +/- 0.6 and 2.05 +/- 0.55 ng/ml respectively. No significant modifications were found in AMH levels during pregnancy and in the early puerperium. CONCLUSIONS: This study has obtained information on AMH and on the possible relationship with FSH. We hypothesize that the profile of the new marker of ovarian activity AMH may indicate that initial non-cyclic ovarian follicular activity during pregnancy is not abolished. Moreover FSH, does not seem to play a direct role on AMH synthesis and secretion.  相似文献   
5.
The authors analyze the incidence of early mechanical and infective CSF shunt complications and various factors that might be correlated with the incidence in a series of 170 children affected by hydrocephalus and meningomyelocele (MM), with the aim of finding specific risk factors related to this particular type of hydrocephalus. Factors investigated for correlation with CSF shunt malfunction are the following: level of the spinal malformation, age of the patient at MM repair, age at diagnosis of hydrocephalus, degree of the ventricular dilatation, age at CSF shunt implantation, modality of the surgical procedure, characteristics of CSF at operation. In the first postoperative year following CSF shunting, 45.9% of the patients presented one shunt malfunction, three-quarters of which were due to mechanical causes, and one quarter to infection. Age of the patient at diagnosis of hydrocephalus and at CSF shunt operation did not significantly influence shunt patency, nor did the surgical modality (programmed vs emergency procedure). On the other hand, MM level did influence the outcome of CSF shunting: a higher percentage of malfunctions (and in particular of infective complications) was observed among the patients with high level MMs than in the group with more caudal location of the spinal defect. Similarly, the degree of ventricular dilatation correlated with the incidence of complications (more severe ventricular dilatation was associated with the highest incidence of complications). The order in which MM repair and CSF shunting were carried out and the age of the patients at MM repair did not affect the occurrence of mechanical complications, whereas they had a significant effect on the incidence of infective complications. In fact, the rate of overall complications, and of infective complications in particular, was proportional the age at MM repair. Furthermore, the group of children who underwent to MM repair and CSF shunting simultaneously scored the lowest percentage of complications, although these were mainly infections; the highest incidence of complications (and in particular of infective ones) was observed in the children who underwent CSF shunting first. The most striking correlation, however, was found with the characteristics of CSF. While normal CSF values correlated with an overall incidence of complications of 39.2%, abnormal CSF values were correlated with a rate of complications of 90.9%; in particular, the rates of infective complications were 2.7% and 77.3%, respectively. On the grounds of these observations a protocol is proposed of temporary CSF external drainage in children requiring prompt relief of increased intracranial pressure but at risk for the presence of a leaking spinal defect or of a MM left unrepaired for more than 48 h.  相似文献   
6.
7.
Adjuvant arthritis (AA) is a T cell mediated disease which can be induced in genetically susceptible rats by immunization with heat-killed Mycobacterium tuberculosis ( Mt ) suspended in incomplete Freund's adjuvant. The critical mycobacterial T cell epitope for the induction of AA was previously identified as residues 178-186 of the mycobacterial 65 kDa heat shock protein ( Mt. hsp65 178-186 ). It was suggested that the development of AA was due to molecular mimicry between a mycobacterial epitope and a cartilage-associated self-antigen. However, until now such cartilage-associated mimicry epitope has not been identified. In this study we designed a computer search profile to predict mimicry self-epitopes, and investigated whether one or more of these self-epitopes could serve as mimicry epitopes in AA. Although several of these self-epitopes were recognized by arthritogenic T cells, no cross-reactivity was found between T cells specific for these self-epitopes and Mt. hsp65 178-186 specific T cells.  相似文献   
8.
9.

Background

Adenosine kinase deficiency is a recently described defect affecting methionine metabolism with a severe clinical phenotype comprising mainly neurological and hepatic impairment and dysmorphism.

Methods

Clinical data of 11 additional patients from eight families with adenosine kinase deficiency were gathered through a retrospective questionnaire. Two liver biopsies of one patient were systematically evaluated.

Results

The main clinical symptoms are mild to severe liver dysfunction with neonatal onset, muscular hypotonia, global developmental retardation and dysmorphism (especially frontal bossing). Hepatic involvement is not a constant finding. Most patients have epilepsy and recurrent hypoglycemia due to hyperinsulinism. Major biochemical findings are intermittent hypermethioninemia, increased S-adenosylmethionine and S-adenosylhomocysteine in plasma and increased adenosine in urine. S-adenosylmethionine and S-adenosylhomocysteine are the most reliable biochemical markers. The major histological finding was pronounced microvesicular hepatic steatosis. Therapeutic trials with a methionine restricted diet indicate a potential beneficial effect on biochemical and clinical parameters in four patients and hyperinsulinism was responsive to diazoxide in two patients.

Conclusion

Adenosine kinase deficiency is a severe inborn error at the cross-road of methionine and adenosine metabolism that mainly causes dysmorphism, brain and liver symptoms, but also recurrent hypoglycemia. The clinical phenotype varies from an exclusively neurological to a multi-organ manifestation. Methionine-restricted diet should be considered as a therapeutic option.
  相似文献   
10.
Clinical Oral Investigations - The aim of this systematic review was to explore the efficacy of different minimal invasive surgical (MIS) and non-surgical (MINST) approaches for the treatment of...  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