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41.
Hereditary hemochromatosis (HH) is a common preventable disorder of iron overload that can result in liver cirrhosis and reduced lifespan. Most HH is due to homozygosity for the HFE p.C282Y substitution. We conducted a study of screening for p.C282Y in high schools where p.C282Y heterozygotes (CY) individuals were informed of their genotype by letter. We studied whether these individuals understood the implications of their genotype, whether this resulted in anxiety or reduced health perception and whether cascade testing was higher in families of CY than wild‐type homozygous (CC) individuals. We found 586 of 5757 (1 in 10) screened individuals were CY. One month after receiving their result, 83% correctly answered that they have one copy of p.C282Y. There was no adverse change in anxiety or health perception from prior to screening to 1 month after receiving results. Significantly more family members of CY individuals than CC individuals were informed about HH and had testing for HH. In conclusion, we found that informing CY individuals of their genotype does not increase anxiety and the implications are generally well understood. This leads to cascade testing in a minority of families. CY individuals should be informed of their genetic status when identified by population screening.  相似文献   
42.
Aim:  The classical combination of abdominal pain, vomiting, rectal blood loss and a palpable abdominal mass is only present in a minority of children with intussusception. Neurological signs and symptoms have been described, but are not a well understood phenomenon. We performed a retrospective study to ascertain the frequency and nature of these symptoms and to describe the characteristics of the patients presenting in this atypical way.
Methods:  The records of 58 children presenting with intussusception from 2003 to 2008 were reviewed for abdominal and neurological signs and symptoms, duration of symptoms and effectiveness of treatment.
Results:  In 10 out of 58 patients (17%), one or more neurological symptoms were recorded at presentation, with lethargy being the most frequent, followed by hypotonia and fluctuating consciousness. The patients with neurological abnormalities were significantly younger and presented with a shorter duration of symptoms. Therapy was more invasive, although not statistically significant, in this patient category.
Conclusion:  Intussusception should be considered in the differential diagnosis in young children presenting with lethargy, hypotonia and/or sudden alterations of consciousness even in the absence of the classical symptoms of intussusception.  相似文献   
43.
Neuropeptides such as corticotropin-releasing factor (CRF) may play a role in regulating the pronounced seasonal changes in food intake shown by white-crowned sparrows (Zonotrichia leucophrys gambelii). White-crowned sparrows held on short day length received injections into the third ventricle (icv) of saline or 5.0, 15.0, and 30 microg/kg. Meal size over the subsequent 180 min was significantly depressed in a dose-dependent fashion. Other non-specific behaviors such as preening, hopping, and immobile behaviors appeared to not be affected by a dose that suppressed food intake. This experiment suggests that white-crowned sparrows, when weight-stable, respond to CRF in a manner comparable with several mammalian species.  相似文献   
44.
A number of approaches have been developed in recent years to try effectively to engage service users in the process of planning and delivering health-care services. The consumerist methodology for the strategy described in this paper was designed to maximise staff involvement in capturing user views, in order to develop services at a district general hospital. This strategy--the Patient Care Development Programme (PCDP)--provides a framework for both staff and patient involvement in shaping and influencing the development of health-care services. Uses the findings from applying the strategy to modify care packages, roles, skills, layouts, protocols and procedures, in response to both the "shortfalls" and the service strengths that the patient's view uncovers. Discusses the results of an evaluation of the programme which has been replicated in another part of the UK. The PCDP now forms part of a clinical governance framework and is being used to develop multi-agency integrated care pathways.  相似文献   
45.
Despite the increasing popularity of antibiotic prophylaxis to reduce febrile morbidity in patients who undergo cesarean delivery, little is known of the pharmacokinetics of antibiotics in the patient at term gestation. This study was designed to elucidate the pharmacokinetics of cefoxitin when administered intravenously or by uterine and peritoneal lavage at cesarean section. Significant differences were found in the values for total body clearance area under the serum concentration-time curve (AUC), and K21 of cefoxitin administered intravenously to pregnant patients at term gestation compared to values for these parameters observed in nonpregnant patients. The concentration of cefoxitin in decidual tissue after uterine and peritoneal lavage with the antibiotic was 92.5 +/- 10.1 micrograms/gm (mean +/- SEM), whereas the concentration of cefoxitin in decidual tissue after intravenous administration of the antibiotic was 36.9 +/- 10.5 micrograms/gm (mean +/- SEM). This difference is statistically significant (p less than 0.05). We conclude that the pharmacokinetics of cefoxitin are altered in the pregnant patient as evidenced by the increased rapidity of clearance of the antibiotic (total body clearance for cefoxitin in pregnant patients, 20.41 L/hr). Moreover, uterine and peritoneal lavage results in significant tissue concentrations of antibiotic, which is of potential importance since the decidua is a presumed site of initiation of bacterial infection after cesarean section.  相似文献   
46.
The tipE gene, originally identified by a temperature-sensitive paralytic mutation in Drosophila, encodes a transmembrane protein that dramatically influences sodium channel expression in Xenopus oocytes. There is evidence that tipE also modulates sodium channel expression in the fly; however, its role in regulating neuronal excitability remains unclear. Here we report that the majority of neurons in both wild-type and tipE mutant (tipE-) embryo cultures fire sodium-dependent action potentials in response to depolarizing current injection. However, the percentage of tipE- neurons capable of firing repetitively during a sustained depolarization is significantly reduced. Expression of a tipE+ transgene, in tipE- neurons, restores repetitive firing to wild-type levels. Analysis of underlying currents reveals a slower rate of repolarization-dependent recovery of voltage-gated sodium currents during repeated activation in tipE- neurons. This phenotype is also rescued by expression of the tipE+ transgene. These data demonstrate that tipE regulates sodium-dependent repetitive firing and recovery of sodium currents during repeated activation. Furthermore, the duration of the interstimulus interval necessary to fire a second full-sized action potential is significantly longer in single- versus multiple-spiking transgenic neurons, suggesting that a slow rate of recovery of sodium currents contributes to the decrease in repetitive firing in tipE- neurons.  相似文献   
47.
48.
BACKGROUND: Changes in flow to the gut and the kidney during hemorrhage and resuscitation contribute to organ dysfunction and outcome. We evaluated regional and splanchnic oxygen (O2) flow distribution and calculated oxygen supply distribution during hemorrhage and reperfusion and compared them with global measures. METHODS: Seven anesthetized pigs were instrumented to evaluate global hemodynamics, visceral blood flow, and oxygen transport. Tonometric pH probes were positioned in the stomach and jejunum. Animals were bled to 45 mm Hg for 1 hour. Crystalloids and blood were infused during the following 2 hours to normalize blood pressure, heart rate, urine output, and hemo- globin. RESULTS: During hemorrhage, mesenteric flow and O2 consumption were significantly decreased, whereas systemic consumption remained normal. Renal flow was reduced, but renal O2 consumption remained normal. After resuscitation, despite normal hemodynamics, neither systemic, mesenteric, nor renal O2 delivery returned to baseline. Lactate remained significantly increased. Arterial pH, base excess, and gastric and jejunal pH were all decreased. CONCLUSION: During hemorrhage, the gut is more prone than other regions to O2 consumption supply dependency. After resuscitation, standard clinical parameters do not detect residual O2 debt. Lactate, arterial pH, base excess, and intramucosal gut pH are all markers of residual tissue hypoperfusion.  相似文献   
49.
Rademaker KJ, Groenendaal F, Jansen GH, Eken P, de Vries LS. Unilateral haemorrhagic parenchymal lesions in the preterm infant: shape, site and prognosis. Acta Pædiatr 1994;83:602–8. Stockholm. ISSN 0803–5253 In a prospective cranial ultrasound study of 544 infants with a gestational age of 32 weeks or less, 20 (3.6%) infants were diagnosed as having a unilateral parenchymal lesion (PL). Based on the shape of the PL and the evolution on ultrasound, the infants were divided into three groups: group I consisted of 11 infants, in whom the PL was triangular/fan-shaped and separate from the ventricle. The PL evolved into small cystic lesions; group II comprised 3 infants who had a PL with a similar shape, but partially communicating with the ventricle; group III consisted of 6 infants who had a globular-shaped lesion in communication with the ventricle. In groups II and III, the PL evolved into one porcncephalic cyst. The PL was considered to be due to venous infarction in all cases with intraventricular haemorrhage preceding the PL in 7 cases. Sixteen infants survived. A postmortem was performed in 2 of the 4 infants who died, confirming the diagnosis of venous infarction. Neurologicdl sequelae were present in only 2 cases in the first group, while all 6 survivors of the other two groups developed mild to severe hemiplegia. Long-term follow-up was not always available and 4 of the 18 survivors were still less than 18 months when last seen. In 9 of the 11 infants in group I, the PL was localized in the frontoparietal region, while in 8 of the 9 infants in group II or III, the PL was beyond the trigone in the occipital region. The outcome of the unilateral PL is not always unfavourable. It was evident that not only the shape of the lesion and whether or not there was communication with the lateral ventricle, but also the site of the lesion (whether or not it extended into the occipital periventricular white matter) appeared to be important with regard to neurodevelopmental outcome.  相似文献   
50.
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