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991.
A family is reported in which there is one case of adrenomyeloneuropathy, one case of Addison's disease and at least three heterozygous females with spastic paraparesis and peripheral neuropathy. Adrenomyeloneuropathy has not been reported previously in Scandinavia. The differences in the clinical picture between the sexes and at different ages are emphasized. Elevation of the levels of very-long-chain fatty acids in plasma is a characteristic feature of the disease and confirms the diagnosis. Some recent reports in the literature seem to provide some hope that the clinical manifestations of adrenomyeloneuropathy/adrenoleukodystrophy may be prevented. 相似文献
992.
993.
EMILIO BOSSI ETIENNE E. JOSS ROLF P. ZURBRÜGG 《Acta paediatrica (Oslo, Norway : 1992)》1973,62(4):401-404
Different growth parameters and their graphical presentation in disorders with advanced and retarded bone age are discussed. Their usefulness for the evaluation of the effect of treatment on growth and maturation is compared. In precocious puberty, more information is obtained when height is plotted against bone age instead of chronological age. It is more reasonable from a physiological standpoint to plot height velocity against bone age rather than chronological age. For the evaluation of the efficiency of treatment on adult height prognosis in precocious puberty, two possibilities are proposed: height velocity expressed as height increment per bone age year, or the quotient height age increment/bone age increment. However, where skeletal maturation is severely retarded, as in hypopituitary growth retardation, these growth parameters should be related in the conventional way to chronological age, rather than to bone age. 相似文献
994.
Paul Matz Christopher Turner Philip R. Weinstein Stephen M. Massa S. Scott Panter Frank R. Sharp 《Brain research》1996,713(1-2)
The heme released following subarachnoid hemorrhage is metabolized by heme-oxygenase (HO) to biliverdin and carbon monoxide (CO) with the release of iron. The HO reaction is important since heme may contribute to vasospasm and increase oxidative stress in cells. HO is comprised of at least two isozymes, HO-2 and HO-1. HO-1, also known as heat shock protein HSP32, is inducible by many factors including heme and heat shock. HO-2 does not respond to these stresses. To begin to examine HO activity following subarachnoid hemorrhage (SAH), the expression of HO-1 and HO-2 was investigated after experimental SAH in adult rats. Immunocytochemistry for HO-1, HO-2 and HSP70 proteins was performed at 1, 2, 3 and 4 days after injections of lysed blood, whole blood, oxyhemoglobin and saline into the cisterna magna. A large increase in HO-1 immunoreactivity was seen in cells throughout brain following injections of lysed blood, whole blood, and oxyhemoglobin but not saline. Lysed blood, whole blood and oxyhemoglobin induced HO-1 in all of the cortex, hippocampus, striatum, thalamus, forebrain white matter and in cerebellar cortex. HO-1 immunoreactivity was greatest in those regions adjacent to the basal subarachnoid cisterns where blood and oxyhemoglobin concentrations were likely highest. Double immunofluorescence studies showed the HO-1 positive cells to be predominately microglia, though HO-1 was induced in some astrocytes. HO-1 expression resolved by 48 h. HO-2 immunoreactivity was abundant but did not change following injections of blood. A generalized induction of HSP70 heat shock protein was not observed following injections of lysed blood, whole blood, oxyhemoglobin, or saline. These results suggest that HO-1 is induced in microglia throughout rat brain as a general, parenchymal response to the presence of oxyhemoglobin in the subarachnoid space and not as a stress response. This microglial HO-1 response could be protective against the lipid peroxidation and vasospasm induced by hemoglobin, by increasing heme clearance and iron sequestration, and enhancing the production of the antioxidant bilirubin. 相似文献
995.
G. Massa M. Vanderschueren-Lodeweyckx J. -P. Fryns 《European journal of pediatrics》1992,151(12):893-894
In the mothers of two girls with Turner syndrome due to a deletion of the short arm of an X chromosome, the same chromosomal anomaly was detected. Both mothers and daughters had short stature but normal pubertal development. Short parents and normal pubertal development do not exclude Turner syndrome in a girl with small stature. 相似文献
996.
Immunocytochemical examination of the presence of amelogenin during the root development of rat molars 总被引:2,自引:0,他引:2
The presence of enamel proteins, especially amelogenins, during root development has been a subject of controversy for a long time. Whereas some studies have reported the presence of enamel proteins on the root surface, others were not able to detect them at these places. Since microwave (MW) processing has been shown to improve the antigen retention in mineralised tissues, we have applied MW techniques to ultrastructurally analyse the presence of amelogenin during root formation in rat molars. Upper molar tooth germs from 12 and 13-day-old Wistar rats were fixed in 0.1% glutaraldehyde + 4% formaldehyde under MW irradiation. They were then decalcified in 4.13% EDTA, dehydrated in graded concentrations of ethanol and embedded in LR White Resin. Ultrathin sections were processed for post-embedding colloidal gold immunolabelling using a chicken egg yolk antibody against a 24 kDa rat amelogenin. Then, the grids were incubated with a rabbit anti-chicken IgG secondary antibody and with a protein A-gold complex. The immunoreactivity for 24-kDa amelogenin was detected in the cytoplasm of the epithelial diaphragm cells--the most apical portion of the Hertwig's epithelial root sheath (HERS), and in less amounts on the adjacent dental papilla extracellular matrix. Amelogenin was no longer observed at advanced stages of root dentinogenesis or later, during cementogenesis. The restricted presence of amelogenin at the early stages of root formation suggests that this protein may play a role in the differentiation of ectomesenchymal cells into root odontoblasts. 相似文献
997.
Di Pace RF Massa S Ribeiro OG Cabrera WH De Franco M Starobinas N Seman M Ibañez OC 《Carcinogenesis》2006,27(8):1517-1525
Mouse lines produced by bidirectional selection on the basis of maximum (AIRmax) or minimum (AIRmin) acute inflammatory reactions were examined for the development of chemically induced acute colitis and colon tumors and the development of lung tumors. AIRmax mice were more susceptible than AIRmin to acute colitis induced by ingestion of dextran sodium sulfate showing a 3-fold higher disease activity index and presenting an intense inflammatory infiltrate in the base of colon crypts as well as elevated expression of IL-1beta, TNFalpha, IFNgamma and IL-6 mRNA in colon tissue. AIRmax were also more susceptible than AIRmin to colon cancer induced by 2 or 7 weekly doses of 1,2-dimethylhydrazine (DMH), showing significantly higher numbers of colonic aberrant crypt foci (ACF) at 150 days after DMH treatment (P = 0.01) and significantly higher numbers of tumors affecting larger intestinal areas at 300-475 days. At the latter time point, however, multiple lung adenomas and large adenocarcinomas were found in AIRmin but not in AIRmax mice. Treatment of mice with nimesulide for 60 days beginning 24 h before the first of two DMH doses almost completely inhibited the appearance of ACF in both lines. Furthermore, ACF numbers and the degree of acute inflammation directly co-segregated in an F2 (AIRmax x AIRmin) intercross population. The results demonstrate that genetic determinants of the inflammatory response differentially influence susceptibility to colon and lung carcinogenesis in the AIRmax and AIRmin mouse model. 相似文献
998.
In sheep carrying simultaneously extra alpha-globin genes (triplications and quadruplications) and two alpha-chain allelic variants, a gradient of decreasing expression of the downstream genes was previously reported. We show here that in these sheep the proportions of the normal and variant Hbs reflect not only the position effect, but also the differential affinity of one of the alpha variants for the betaA and betaB allelic chains. 相似文献
999.
Despite advances in G-protection, F-16 student pilots continue to demonstrate G-performance inadequacies. The G-Risk Indicator Management (GRIM) Program was introduced at Luke Air Force Base in 2000 to facilitate early detection of G-related problems and to aid in the establishment of tailored ground training programs designed to enhance a student's performance under G. Assessment of anthropomorphic data, previous G-performance, anaerobic fitness, and centrifuge qualification scores comprise the initial assessment in the GRIM Program. Observations from these assessments are used to qualitatively determine the level of risk for the student. In the absence of any historical controls, no conclusions could be drawn with regards to the overall efficiency of the GRIM program. Significant differences were found between groups for anaerobic test scores, centrifuge scores, and gradebook comments. The results from this non-experimental study suggest the need for future studies to better determine the validity of G-risk indicators. 相似文献
1000.
R. Massa R. Lodi B. Barbiroli S. Servidei G. Sancesario G. Manfredi P. Zaniol G. Bernardi 《Acta neuropathologica》1996,91(3):322-329
A late-onset, myopathic variant of phosphofructokinase (PFK) deficiency has been previously described in two patients of
Ashkenazic descent. We report here on a non-Ashkenazic woman with the onset, at the age of 48 years, of a progressive limb
girdle myopathy that was not preceded by a history of exercise intolerance. Muscle biopsy findings at the age of 58 years
showed deposition of amylopectin-like material in muscle fibers and the absence of histochemical PFK activity. Enzymatic PFK
activity in vitro was only 4% of normal. Since the forearm ischemic exercise test induced a sub-normal production of serum
lactate, the patient underwent phosphorus magnetic resonance spectroscopy (31P-MRS), a non-invasive method that allows in vivo assessment of the functional status of the glycolytic pathway and mitochondrial
oxidative metabolism by measuring the high-energy phosphates and cytosolic pH. In vivo, 31P-MRS disclosed a residual glycolytic flux and a normal rate of ATP production both at rest and during exercise. These results
suggest that, in some patients, muscle PFK deficiency may be partial in vivo, and more severe in vitro, possibly due to protein
or mRNA instability rather than absence. The presence of these findings in a patient with the late-onset myopathic form is
compatible with a distinct pathogenetic mechanism, relying on progressive polysaccharide accumulation, rather than on acute
energetic shortage in muscle fibers.
Received: 4 May 1995 / Revised, accepted: 28 September 1995 相似文献