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1.
By 2–3 months, infants engage in exploration of their own body as it moves and acts in the environment. They babble and touch their own body, attracted and actively involved in investigating the rich intermodal redundancies, temporal contingencies, and spatial congruence of self-perception. Recent research is presented, which investigats the spatial and temporal determinants of self-perception and action infancy. This research shows that, in the course of the first weeks of life, infants develop an ability to detect intermodal invariants and regularities in their sensorimotor experience, which specify themselves as separate entities agent in the environment. Recent observations on the detection of intermodal invariants regarding self-produced leg movements and auditory feedback of sucking by young infants are reported. These observations demonstrate that, early in development and long before mirror self-recognition, infants develop a perceptual ability to specify themselves. It is tentatively proposed that young infants’ propensity to engage in self-perception and systematic exploration of the perceptual consequences of their own action plays an important role in the intermodal calibration of the body and is probably at the origin of an early sense of self: the ecological self.  相似文献   
2.
Cigarette smoking is associated with an increased incidence of atherosclerotic diseases. The aim of this study was to examine the progression of the preatherosclerotic lesions previously observed by us in coronary arteries of fetuses of smoker mothers and in infants with smoker parents. We examined the coronary arteries of 34 infants, aged 1–36 months, and the histological and biological [c-fos, proliferating cell nuclear antigen (PCNA), and apoptosis] features of the early atherosclerotic lesions. In 17 infants (50%), at least one parent smoked, generally more than five cigarettes a day. In 18 cases (53%), we observed variable thickening of the coronary walls from preatherosclerotic lesions to juvenile atherosclerotic plaques, related to parental smoking habit. This morphological progression of the lesions was accompanied by a sequence of biological changes in the smooth muscle cells of the tunica media. We suggest that the oxidants present in the gas phase of the parental cigarette smoke pass through the endothelium and induce at first the c-fos gene activation and subsequently the PCNA positivity, that is, a proliferative process.  相似文献   
3.
Generalized arterial calcification of infancy (GACI) is a rare disorder caused by ENPP1 or ABCC6 variants. GACI is characterized by low pyrophosphate, arterial calcification, and high mortality during the first year of life, but the natural course and possible differences between the causative genes remain unknown. In all, 247 individual records for patients with GACI (from birth to 58.3 years of age) across 19 countries were reviewed. Overall mortality was 54.7% (13.4% in utero or stillborn), with a 50.4% probability of death before the age of 6 months (critical period). Contrary to previous publications, we found that bisphosphonate treatment had no survival benefit based on a start-time matched analysis and inconclusive results when initiated within 2 weeks of birth. Despite a similar prevalence of GACI phenotypes between ENPP1 and ABCC6 deficiencies, including arterial calcification (77.2% and 89.5%, respectively), organ calcification (65.8% and 84.2%, respectively), and cardiovascular complications (58.4% and 78.9%, respectively), mortality was higher for ENPP1 versus ABCC6 variants (40.5% versus 10.5%, respectively; p = 0.0157). Higher prevalence of rickets was reported in 70.8% of surviving affected individuals with ENPP1 compared with that of ABCC6 (11.8%; p = 0.0001). Eleven affected individuals presenting with rickets and without a GACI diagnosis, termed autosomal recessive hypophosphatemic rickets type 2 (ARHR2), all had confirmed ENPP1 variants. Approximately 70% of these patients demonstrated evidence of ectopic calcification or complications similar to those seen in individuals with GACI, which shows that ARHR2 is not a distinct condition from GACI but represents part of the spectrum of ENPP1 deficiency. Overall, this study identified an early mortality risk in GACI patients despite attempts to treat with bisphosphonates, high prevalence of rickets almost exclusive to ENPP1 deficiency, and a spectrum of heterogenous calcification and multiple organ complications with both ENPP1 and ABCC6 variants, which suggests an overlapping pathology. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.  相似文献   
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Sera from 263 newborns and infants suspected of congenital toxoplasmosis were tested for the presence of rheumatoid factor (RF) by the latex agglutination test, of which 40 were also tested by the enzyme-linked immunosorbent assay (ELISA). RF was detected in only one serum sample (0.38%), suggesting that false-positive results of the IgM-indirect fluorescent antibody test and the IgM-ELISA due to RF is most unusual in infancy.  相似文献   
6.
Summary Fourteen juvenile patients with small cell gliomas were studied at two institutes. These tumors are believed to form a distinct entity. They arise mostly in the diencephalon or the brain stem and are composed of a poorly differentiated small cell component having a prononounced tendency to differentiate into a glioma. Signs of neuroblastic differentiation were also found with the electron microscope. Small cell gliomas disseminate early and profusely throughout the ventricular walls and the subarachnoid spaces including the spinal meninges. Prognosis is grave, most patients dying within 1 year of diagnosis or surgical intervention. The designation infantile small cell glioma overlaps with both the metastasising gliomas in young subjects of Eade and Urich (1971) and with the primitive neuroectodermal tumor of infancy of Hart and Earle (1973).  相似文献   
7.
大连市幼儿血硒与血铅含量相关性研究   总被引:1,自引:0,他引:1  
采用新极谱法对大连市 84 6例幼儿全血样品进行硒含量测定 ,其值为 12 1 9± 4 0 5 μg/L ,其中男性与女性血硒含量分别为 12 0 4± 4 1 9μg/L (45 4例 ) ,12 3 7± 38 7μg/L (392例 ) ,均处于我国全血硒临床正常值和营养状态 ,男女血硒含量无显著性差异 (P >0 .10 )。血铅含量超过 10 0 μg/L的幼儿血硒含量为 116 7±39 5 μg/L(178例 ) ,与血铅含量正常幼儿血硒含量为 12 3 3± 4 0 6 μg/L(6 6 8例 )比较有显著性差异 (P <0 0 5 )。血铅含量超过 10 0 μg/L的各年龄段幼儿血硒含量无显著性差异 (P >0 10 ) ,但低于各年龄段血铅含量正常的幼儿的血硒含量。  相似文献   
8.
Captopril, an orally active inhibitor of angiotensin-converting-enzyme, offers a new approach in the treatment of renin-induced hypertension, which is refractory to conventional drugs. A 4 months old infant developed after nephrectomy again hypertension which was probably renin-induced. BP did not respond to high doses of methyl-dopa, clonidine, hydralazine, and furosemide. An acute BP response to captopril was seen at a daily dose of 150 mg. During long-term treatment, 75 mg captopril and 12.5 mg hydrochlorothiazide resulted in normalization of BP. In a second child with renin-induced hypertension since the firth month of life, treatment wiht hydralazine, clonidine and hydrochlorothiazide was in part effective, but failure to thrive was progressive. Captopril treatment was started at the age of 20 months. BP was lowered at a daily dose of 75 mg and normalized during long-term therapy with 50 mg. Side effects were not seen.  相似文献   
9.
Cardiac tumours in infancy are rare and are mostly benign with rhabdomyomas, fibromas and teratomas accounting for the majority. The presentation depends on size and location of the mass as they tend to cause cavity obstruction or arrhythmias. Most rhabdomyomas tend to regress spontaneously but fibromas and teratomas generally require surgical intervention for severe haemodynamic or arrhythmic complications. Other relatively rare cardiac tumours too are discussed along with an Indian perspective.  相似文献   
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