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81.
82.
A 4‐month baby with pulmonary atresia, ventricular septal defect, major aortopulmonary collateral arteries (MAPCAs) and an extremely hypoplastic central pulmonary artery developed critical hypoxia following right unifocalization combined with a right Blalock‐Taussig shunt. To increase pulmonary blood flow we stented the left lower MAPCA during extracorporeal membrane oxygenation (ECMO) support. He was successfully weaned from ECMO 2 days after stenting. Percutaneous intervention for a stenosed MAPCA is an effective means of increasing pulmonary blood flow in critically hypoxic patients following unilateral unifocalization, even in the immediate postoperative stage. © 2008 Wiley‐Liss, Inc.  相似文献   
83.
Objectives:   To investigate the pathophysiology of nocturnal polyuria associated with aging.
Methods:   Fifty patients (mean age 67.7 years, range 50–87) with nocturia were recruited for this prospective study. Patients were classified into nocturnal polyuria (NP) and non-nocturnal polyuria (non-NP) groups based on records of their frequency-volume charts. A hypertonic saline infusion test was carried out to evaluate individual osmotic and volume control.
Results:   In the NP group, there was a significantly increased nocturnal diuretic rate compared with the daytime diuretic rate. In the non-NP group, there was a significantly decreased nocturnal diuretic rate compared with the daytime rate. There was also a positive correlation between systolic blood pressure and nocturnal diuretic rate, and a negative correlation between systolic blood pressure and daytime diuretic rate in those with NP, but no correlation in those without NP. Thus, a close relationship between diuretic rates and systolic blood pressure was seen in NP patients. Moreover, a slight overall shift upward from the physiological range of plasma osmolality relative to arginine vasopressin after hypertonic saline loading was seen in those with NP compared with those without. An altered circadian rhythm was also seen in diurnal plasma arginine vasopressin levels in patients with and without NP.
Conclusions:   Patients with nocturnal polyuria are likely to have a more hypervolemic or vasoconstrictive condition. It is considered that non-osmotic control takes on a greater meaning in patients with nocturnal polyuria, though osmotic control contributes less to diuresis within the physiological plasma osmolality range with aging.  相似文献   
84.
A total of 154 stroke patients, 96 males and 58 females, were analyzed to establish the micturitional modality according to the type of detrusor function and the level of activities of daily living (ADL). All patients had only one episode of stroke attack and were checked at least one month after the onset. Localization of cerebral lesion in each patient was evaluated by neurological findings and cerebral angiography in addition to computed tomography of the brain. In the patient groups classified according to the type of detrusor function, micturitional modality was established in 50% of the patients with the underactive type, 70% of those with the overactive type and in 88% of those with normal function. This suggests that the overactive and normal type of detrusor function may not affect establishment of micturitional modality. On the other hand, when classified according to the level of ADL, none established micturitional modality in patients with poor ADL. By contrast, in the patients on higher levels of ADL who were able to transfer themselves from or to a wheel-chair without any assistance it was established in 75%, and in those who were able to gait with or without a brace upon discharged from the hospital, in 91%. It is concluded that establishment of micturitional modality in stroke patients is closely related to the level of ADL or function of lower extremities, but not to localization of the brain lesion.  相似文献   
85.
We have investigated whether poly-L-arginine, with a mean molecular weights of 8.9 and 45.5 kDa (poly-L-Arg (10) and poly-L-Arg (50)), can induce transient and reversible effects involving enhancement of the nasal absorption of fluorescein isothiocyanate-labeled dextran (MW 4.4 kDa, FD-4) and determined the main pathway for the increased transport of FD-4 in rats in vivo. Pre-administration and repeated administration studies were conducted involving the selection of different time intervals between intranasal administration of poly-L-Arg and administration of FD-4, with and without poly-L-Arg, to characterize these transient and reversible effects. The degradation of poly-L-Args in a diluted nasal drip was determined from the fluorescence of degraded poly-L-Arg-fluorescamine products. In the pre-administration study, poly-L-Arg exhibited a transient effect on the increased nasal FD-4 absorption depending on its molecular weight, associated with the degradation rate of poly-L-Arg in mucus. In the repeated administration study, additional poly-L-Arg produced similarly enhanced FD-4 absorption. Confocal laser scanning microscopy showed that fluorescence of FD-4 after co-administration of poly-L-Arg (50) was confined mainly to the paracellular spaces. In conclusion, poly-L-Arg exhibited molecular weight-dependent transient and reversible effects on the enhancement of nasal FD-4 absorption paracellularly in rats in vivo. The enzymatic degradation of poly-L-Arg is one of the key determinants of the transient effect on in vivo enhanced absorption of FD-4.  相似文献   
86.
The high‐flow management of cardiopulmonary bypass (CPB; ≥2.4 L/min/m2) is a standard strategy used at this institute for children with pulmonary atresia (PA) due to a fear that the blood flow may be diverted by the major/minor aortopulmonary‐collateral‐arteries and hypervascularization due to long‐term hypoxia. The purpose of this study was to describe the validity of high‐flow management in children with PA. The CPB records of 23 children with PA who underwent a definitive biventricular repair between Feb 2006 and Nov 2008 were retrospectively reviewed. The mean age at the operation was 33 ± 22 months. The blood‐pressure during bypass was controlled with the same protocol. The mean cooling‐temperature was 28.4 ± 3.7°C. The mean minimum hematocrit was 25.0 ± 3.4%. The mean maximum bypass flow index at the initiation, the mean maximum flow index during aortic cross‐clamping, the mean minimum flow index during aortic cross‐clamping, and the mean maximum flow index after rewarming were 3.1 ± 0.5, 3.1 ± 0.5, 2.6 ± 0.4, and 3.2 ± 0.4 L/min/m2, respectively. The higher bypass flow indexes significantly correlated with the lower serum lactate levels. The lowest oxygen delivery during CPB had significant influences on the urine output during bypass (R = 0.547, P = 0.007), the serum lactate levels at the end of CPB (R = ?0.442, P = 0.035), and the postoperative thoracic effusion (R = ?0.459, P = 0.028). A bypass flow index of 2.4 L/min/m2 may not be sufficient and the maximum requirement of bypass flow index may be 3.2 L/min/m2 or more in this patient population.  相似文献   
87.
Careful rewarming of perfusion blood following cardiopulmonary bypass surgery is critical to a successful outcome, but the optimal rewarming strategy is not clear. The purpose of this study was to derive a formula for a rewarming index (defined as [rewarming time × perfusion flow]/[body weight × body surface area]) that would enable the calculation of the ideal rewarming conditions for pediatric cardiopulmonary perfusion. We retrospectively investigated 220 pediatric cardiopulmonary bypass operations conducted from July 2005 to June 2008 in Okayama University Hospital, Japan. We determined the formula as Φ = (T × Q)/(R × S) = |0.9127P ? 0.0152|, where Φ = rewarming index, T = rewarming time (min), Q = perfusion volume (L), R = body weight (kg), S = body surface area (m2), and P = temperature gap (). The formula will help those who perform pediatric cardiopulmonary bypass surgery to establish ideal perfusion flow conditions and to control physiological temperature during rewarming.  相似文献   
88.
Purpose: To assess the efficacy of diazepam suppositories at preventing febrile seizure recurrence during a single febrile illness to determine how to treat children with a febrile seizure on presentation at the hospital. Methods: We studied 203 children with febrile seizures from December 2004 through March 2006. On admission between December 2004 and May 2005, a diazepam suppository was administered to the patients. Patients seen between June 2005 and March 2006 were not treated with antiepileptic drugs on admission. Results: We saw a significant difference in the rate of recurrence of febrile seizures between children treated with diazepam and those who were not. Recurrences were observed in 2 (2.1%) of 95 children treated with diazepam and in 16 (14.8%) of 108 untreated children. For the 108 untreated patients, the median age was 22.8 months in those with recurrences and 30.6 months in those without, confirming that a younger age was related to a recurrence. Conclusions: A diazepam suppository after a febrile seizure will reduce the incidence of recurrent febrile seizures during the same febrile illness. However, a diazepam suppository after a febrile seizure should be used after carefully considering the benefits and potential adverse effects.  相似文献   
89.

Background  

The RGS family, comprising 22 homologues of proteins, plays a role in cellular proliferation, differentiation, membrane trafficking, and embryonic development through the involvement of the mitogen-activated protein kinase signaling pathway.  相似文献   
90.
BackgroundIn patients with end-stage renal disease, angiotensin II type 1A receptor (AT1) blockade attenuates the associated cardiac dysfunction. We investigated the molecular signaling mediating that effect.Methods and ResultsWe used 5/6 nephrectomy to induce significant renal dysfunction in AT1 knockout (AT1KO) and wild-type mice (WT). Twelve weeks after nephrectomy, WT showed significant left ventricular dilation and dysfunction that were accompanied by cardiomyocyte hypertrophy, fibrosis, and reduced capillary density. All of these effects were significantly mitigated in AT1KO. Nephrectomy led to upregulation of myocardial expression of AT1, transforming growth factor-β1 (TGF-β1), matrix metalloproteinase (MMP)-2, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), and phosphorylated Akt (p-Akt), and also led to increased oxidative damage in cardiomyocytes. In AT1KO, TGF-β1, TIMP-1, oxidative damage levels were lower, whereas MMPs and p-Akt levels were higher. Treating nephrectomized WT mice with valsartan (an AT1 blocker), but not hydralazine, improved cardiac function and altered molecular signaling in a manner similar to that seen in AT1KO mice. Notably, AT1 expression was downregulated in valsartan-treated but not hydralazine-treated hearts.ConclusionsThese findings provide novel insight into the mechanism underlying the beneficial effects of AT1 blockade on cardiac function in a model of renal dysfunction–associated heart failure.  相似文献   
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