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101.
Long-term renal isografts in humans and laboratory animals exhibit features similar to those of chronic allograft nephropathy (CAN), indicating that antigen-independent factors, such as acute renal ischemia, are likely to be involved in the development of CAN. Hepatocyte growth factor (HGF) has been demonstrated to play a renotropic role in renal regeneration and protection from acute ischemic injury. This study was thus conducted to investigate the effect of HGF on the development of CAN, using an established rat model. HGF was administered daily (100 microg/d, intravenously) for 4 wk after engraftment. Control animals received saline solution. Allografts from control animals exhibited early evidence of severe structural collapse and necrotic cell death in the proximal tubules and outer medulla, with mononuclear cell infiltration, within 1 wk after engraftment. This was followed by sequential upregulation of adhesion molecules and cytokines, accompanied by dense macrophage infiltration. Fibrogenic events, as indicated by marked increases in transforming growth factor-beta1 expression and the accumulation of smooth muscle alpha-actin, occurred during the same period. Control animals ultimately developed features typical of CAN, with functional deterioration and severe histologic changes; a survival rate of 50.6% by 32 wk was observed. In contrast, remarkably little early injury and no late fibrogenic events were observed for the HGF-treated group. All treated animals survived, with well preserved graft function, during the 32-wk follow-up period. These results indicate that renal protection and recovery from early allograft injury with HGF treatment greatly contribute to a reduction of susceptibility to the subsequent development of CAN in a rat model. The potential application of HGF in the prevention of CAN warrants further attention.  相似文献   
102.
To estimate the prevalence and distribution of salmonellae, especially Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis), in Western Japan, an investigation was conducted of the chicken industry and environmental sources between 1995 and 1998. Salmonellae were isolated from 34 of 90 samples (37.8%) of raw chicken parts, 34 of 98 faecal samples (34.7%) at 35 broiler farms, 11 of 59 samples (18.6%) of liquid eggs, and from 71 of 272 samples (26.1%) of swab specimens from equipment and cracked or faecally soiled shell eggs at the processing facilities. Salmonellae, including S. Enteritidis, were also isolated from swab samples of henhouses associated with one of the shell-egg processing facilities (11 samples out of 55, 20%). In the broiler meat production environment, S. Infantis was dominant. Twenty-two of 36 sewage samples (61.1%) and 16 of 72 samples (22.2%) taken from 5 rivers contained salmonellae including S. Enteritidis. S. Enteritidis isolates were analysed with pulsed-field gel electrophoresis using enzyme Bln I. Thirty-four isolates from shell-egg processing facilities and henhouses, obtained over several years, had the same pulsed-field profile as isolates obtained from four individual outbreaks that occurred in this location in 1997. One of the clonal lines of S. Enteritidis, among multiple serovars of salmonellae in the environment, was thought to have distributed in reservoirs, laying hens, for several years, and continued to cause outbreaks in this area.  相似文献   
103.
The ideal timing to implement anterior cruciate ligament injury prevention programs with respect to maturation is unclear. The purpose of this study was to investigate the effects of an injury prevention program on knee mechanics in early-, late-, and post-pubertal females. In the study, 178 adolescent female basketball players were assigned to six groups: early-pubertal training, early-pubertal control, late-pubertal training, and late-pubertal control, post-pubertal training, and post-pubertal control. The training groups performed an injury prevention program for six months. Medial knee displacement, knee flexion range of motion, and the probability of high knee abduction moment were assessed before and after the training period. After the six-month training period, medial knee displacement was significantly increased in the early-pubertal control group whereas it was unchanged in the early-pubertal training group. Knee flexion range of motion was significantly decreased in the early-pubertal control group whereas it did not change in the early-pubertal training group. The probability of high knee abduction moment was increased in the early-pubertal control group whereas it was unchanged in the earl-pubertal training group. The probability of high knee abduction moment was also decreased in the post-pubertal training group whereas it did not change in the post-pubertal control group. The program limited the development of high-risk movement patterns associated with maturation in early puberty while improving the knee mechanics in post-pubertal adolescents. Therefore, an injury prevention program should be initiated in early puberty and continue through the post-puberty years.Key points
  • An ACL injury prevention program limited the development of high-risk movement patterns associated with maturation in early puberty while it improved the knee mechanics in post-pubertal adolescents.
  • An improvement through a program might not be obvious due to the natural development of the faulty movement patterns in early-pubertal adolescents, while significant improvement through the training program can be expected in post-pubertal adolescents.
  • An ACL injury prevention program should be initiated in early puberty and continue through the post-puberty years.
Key words: Knee injuries, landing, neuromuscular control, puberty  相似文献   
104.
This study evaluated the pulp biocompatability of a new light-cured composite resin which was placed in etched glass-ionomer-lined cavities of monkey teeth. The pulpal response to this material was less than that to zinc-oxide eugenol cement in each observation period. Therefore this material seems to meet acceptable biocompatability standards in nonhuman primates.  相似文献   
105.
A 72 years old man developed slowness of the motion and orthostatic hypotension at the age of 69. Neurological examination showed slight finger tremor, rigidity of extremities, bradykinesia, and marked orthostatic hypotension. The illness progressed steadily and the patient died of pneumonia. At autopsy brain weighed 1220 g. Grossly the putamen was bilaterally shrunken, the color of the substantia nigra and locus ceruleus became pale. Base of the pons and the cerebellum were atrophic. Microscopically the most remarkable change was seen in the striato-nigral system. In the putamen, there were severe loss of small neurons and intense gliosis and brownish pigments were observed in the neuropil and within some of the astrocytes. There found neuronal loss and gliosis in the substantia nigra. A few Lewy bodies were seen in the substantia nigra. In the cerebellum there were slight loss of Purkinje cell and many torpedos were seen. There were demyelination and fibrirally gliosis in the cerebellar white matter except the hilus of dentate nucleus. The transverse pontocerebellar fibers were degenerated and fibrirally gliosis was seen there. The inferior olivary nuclei showed neuronal loss and astrocytosis. But the degeneration of the olivo-ponto-cerebellar system in this case was not so severe as the typical case of OPCA. In the spinal cord there was depletion of nerve cells in the intermediolateral nuclei and Onufrowitz nuclei. Slight neuronal loss and many spheroids were observed in the anterior horns and there was demyelination in the corticospinal tracts.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
106.
The relationship between hypothalamic-pituitary-adrenal (HPA) function and the noradrenergic system was examined in patients with affective and with schizophrenic disorders. In response to the Dexamethasone Suppression Test (DST), serum cortisol, plasma catecholamine levels, and serum creatine kinase (CK) activity were measured. Among patients with major depression, those with higher post-DST cortisol levels had higher plasma catecholamine levels and lower serum CK activity. Among acute schizophrenic patients, those with higher serum CK activity had higher baseline and post-DST cortisol levels. These results indicate that in both major depression and in acute schizophrenia, there is a dysfunction of the HPA axis and the noradrenergic system, but the noradrenergic dysfunctions are different in the two disorders.  相似文献   
107.
To examine the possible involvement of D1 dopamine receptors in behavioral sensitization induced by subchronic methamphetamine (MAP) administration, regional D1 receptors labeled with [3H]SCH 23390 were examined using binding assay and quantitative autoradiography. Rats received 4 mg/kg/day MAP (i.p.) for 14 days, and were decapitated after an abstinence period of 24 h, 7 days or 21 days. In MAP-treated rats, a significant decrease in Kd in the mesolimbic area was observed 24 h but not 7 days after the last injection. Neither Kd nor Bmax changed in the striatum or medial prefrontal cortex of MAP-treated rats after any period of abstinence. Autoradiography revealed a significant increase in specific [3H]SCH 22390 binding in the lateral part of the substantia nigra pars reticulata (SNr) of MAP-treated rats. Since this increase lasted up to 21 days after cessation of subchronic MAP administration, it is suggested that lasting increase in the nigral D1 receptors may be associated with the biological changes underlying MAP-induced behavioral sensitization.  相似文献   
108.
Intracerebral dialysis was used to study the mechanism underlying cross-behavioral sensitization between methamphetamine (MAP) and cocaine. The challenge injection of cocaine caused a significantly greater increase in striatal perfusate dopamine (DA) levels in MAP-pretreated rats than in saline-pretreated rats. Similarly, the challenge injection of MAP caused a significantly greater increase in extracellular DA levels in cocaine-pretreated rats than in control rats. These results suggest that an enhancement in striatal DA efflux may play an important role in cross-behavioral sensitization between MAP and cocaine.  相似文献   
109.
110.
We have examined the effect of neuromedin C on exocrine pancreatic secretion both in vivo and in vitro, and compared its bioactivity with those of related peptides. In anesthetized dogs, neuromedin C caused a dose-dependent initial reduction of pancreatic blood flow and an increase in secretin-stimulated exocrine pancreatic secretion, and had almost the same potency as gastrin-releasing peptide (GRP) in decreasing pancreatic blood flow. A potent stimulatory effect on exocrine pancreatic secretion was found in conscious dogs accompanied by a significant elevation in the circulating cholecystokinin (CCK) levels. In isolated rat pancreatic acini, amylase was released dose-dependently in response to neuromedin C. This study demonstrates that neuromedin C (a smaller molecular form of GRP) possesses potent bioactivity on exocrine pancreas and suggests that two factors may be involved in the mechanism by which this peptide effects exocrine secretion, namely; direct stimulation on acinar cells and stimulation of CCK release.  相似文献   
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