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11.

Background

The potassium content of University of Wisconsin solution (UW) is 125 mEq/L and that of histidine-tryptophan-ketoglutarate solution (HTK) only 9 mEq/L. The aim of the present study was to analyze their effects to change potassium levels on reperfusion among patients undergoing living-donor liver transplantation.

Methods

Anesthesia records of adult living-donor liver transplant patients were reviewed retrospectively. Patients received liver graft preserved in UW were grouped in group I (GI) and HTK in group II (GII). The potassium levels in the anheptic phase were compared with those 5 minutes after reperfusion using paired Student t tests. P values of <.05 were regarded to be significant.

Results

Eighty-five GI patients showed the potassium significantly decreased from 3.76 ± 0.70 to 3.60 ± 0.74, whereas the change among 355 GII patients was almost unremarkable: 4.00 ± 0.57 to 3.96 ± 0.06 mEq/L.

Conclusions

Although UW contains a higher potassium content, it seems to have no negative impact on changes in serum potassium levels; in contrast it decreased the potassium level significantly at 5 minutes after reperfusion. Both preservation solutions maintain the patients' potassium levels within the normal range.  相似文献   
12.
Activity and functional significance of the renal kallikrein-kinin-system in polycystic kidney disease of the rat.BACKGROUND: The kallikrein-kinin-system is a complex multienzymatic system that has been implicated in the control of systemic blood pressure, glomerular filtration rate, and proteinuria. The present study investigated its functional role in rat polycystic kidney disease (PKD), which is characterized by progressive renal failure and proteinuria in the absence of systemic hypertension and stimulated renin-angiotensin-system.METHODS: Kallikrein and bradykinin levels were measured in plasma and urine of rats with polycystic kidneys and compared to non-affected controls (SD) and rats with reduced renal mass. The functional relevance of the kallikrein-kinin system (KKS) was assessed by the effects of a short-term treatment with either a selective bradykinin (BK) B1-receptor antagonist (des-Arg9-[Leu8]-BK), a B2-receptor antagonist (HOE 140), an angiotensin converting enzyme inhibitor (ramipril), or an angiotensin II-receptor blocker (HR 720) on systemic and renal parameters.RESULTS: Urine levels of kallikrein were increased threefold in 9-month-old PKD, and BK excretion was increased tenfold in 3-month and 30-fold in 9-month-old PKD compared to age-matched SD rats. Blood pressure in 9-month-old PKD rats was decreased to the same degree by ramipril and HR 720. In contrast, only ramipril and HOE 140 significantly reduced proteinuria and albuminuria, independent from creatinine clearance. This effect was accompanied by an increased excretion of bradykinin. The B1 receptor antagonist had no influence on functional renal parameters.CONCLUSIONS: The present study demonstrates an age-dependent activation of the renal KKS in rats with polycystic kidney disease. The bradykinin B2-receptor is involved in the pathogenesis of proteinuria, independent from systemic blood pressure or creatinine clearance. The antiproteinuric effect of ramipril in this model is angiotensin II-independent and related to its influence on the renal KKS.  相似文献   
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PURPOSE: Laparoscopic radiofrequency ablation is safe, practicable, and combines minimally invasive surgery with the advantages of laparotomy. However, application of the laparoscopic freehand puncture is restricted because of capnoperitoneum and the consequent fixation of the needle on two different points. The use of a laparoscopic ultrasound probe with a canal for puncture can solve this problem and improve precision. However, a stiff needle limits the necessary angulation that is needed to reach right-lateral and cranial liver metastases. Therefore we present a new navigation tool for laparoscopic interventions. MATERIALS AND METHODS: The US Guide 2000 (Ultra Guide, Tirat Hacarmel, Israel) is an independent navigation system compatible with all ultrasound machines and has six degrees of freedom. After proper evaluation of this system under operating room conditions during transcutaneous radiofrequency ablation, we used this technique in laparoscopic radiofrequency ablation. A special adapter was developed to attach the ultrasound-based navigation system to a laparoscopic ultrasound probe. After calibrating the system with an ultrasound phantom, laparoscopic navigation in a liver organ model was studied. RESULTS: Even in cases of angulation of the ultrasound probe no disturbances of the navigation system could be detected. Anatomic landmarks in the liver could be safely reached. No interaction between the navigation system and the laparoscopic ultrasound probe or operating instruments was observed. CONCLUSION: Our preliminary results show the feasibility of this technique in laparoscopic radiofrequency ablation. The use of an ultrasound-based laparoscopic inline navigation system offers the possibility of out-of-plane needle placement and could combine the flexibility of freehand puncture with the accuracy of a canal for puncture. This could increase the safety and accuracy of punctures.  相似文献   
14.
Background and aims Radiofrequency-ablation (RFA) is increasingly used for destruction of unresectable primary and secondary liver tumors. We report our experience in the use of RFA for the management of unresectable hepatic malignancies. Patients and methods Between February 2000 and December 2004 we have undertaken 120 RFA procedures to ablate 426 unresectable primary or metastatic liver tumors in 88 patients. RFA was performed via laparotomy (n=68), laparoscopy (n=9) or a percutaneous approach (n=43). Primary liver cancer was treated in seven patients (8%) and metastatic liver tumors were treated in 81 patients (92%). All patients were followed to assess complications, treatment response and recurrence of malignant disease. Results Procedure-related complication rate was low (3.4%). During a mean follow-up of 21.2 months, 15 patients had local tumor progression (17%), 21 patients (23,9%) had new malignant disease and 27 patients (30.7%) died from intervention-unrelated complications of their malignant disease. Additional liver lesions were identified in 27 (35%) of 77 cases by intraoperative ultrasound. Thirty-six patients received simultaneous resection and RFA. Conclusion RFA is a safe, well-tolerated and effective treatment for patients with unresectable primary and secondary liver malignancies.  相似文献   
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We report on an adult male with Klinefelter phenotype and an isodicentric Y chromosome (47,XX,+idic(Y)(q12)), a combination which has to the best of our knowledge not been reported before. The patient was hospitalized in forensic psychiatry because of repeated delinquency, aggressive, aberrant and inappropriate behavior, and borderline intelligence. Molecular cytogenetic studies (FISH) showed that the SRY gene was present on both ends of the idicY, while there was only one signal for the Yq subtelomere probe. Molecular investigations by multiplex PCR, using STS markers covering the short and long arm of the Y chromosome did not indicate a deletion of Y chromosomal material. Molecular investigations of STR markers located on Xp22.3 and Xq28 indicated paternal origin of the additional X chromosome and an error in paternal meiosis I. Results of FISH analysis and molecular investigations are compatible with a phenotype as described for individuals with a 48,XXYY karyotype and support the findings that isodicentric Y chromosomes are frequently accompanied by other sex chromosomal abnormalities.  相似文献   
18.
Sohn SW  Lee HS  Park HW  Chang YS  Kim YK  Cho SH  Kim YY  Min KU 《Allergy》2008,63(3):268-273
Background:  Although airway hyperresponsiveness (AHR) is a characteristic feature of asthma, it is also frequently present in allergic rhinitis (AR). However, the pathogenesis of AHR is unclear and the roles of cytokines in the airway have not been well established in AR. We sought to compare cytokine mRNA levels in the sputum of AR patients with or without AHR and those of asthma patients, and to evaluate whether differences in cytokine levels are associated with the development of an abnormal airway response and the absence of respiratory symptoms in AR patients with AHR.
Methods:  Airway cells were obtained by sputum induction from 18 AR patients with AHR, 58 AR patients without AHR, and 27 asthma patients. Airway cell cytokine levels, interleukin (IL) -4, IL-5, IL-13, vascular endothelial growth factor (VEGF), and interferon-γ (IFN-γ), were studied at the mRNA level by RT-PCR.
Results:  Vascular endothelial growth factor and IL-5 mRNA levels were significantly higher in AR patients with AHR than in AR patients without AHR, but these were lower than those of asthmatic patients. Eosinophils were significantly higher in AR patients with AHR and in asthmatic patients than in AR patients without AHR. Interleukin-4, IL-13, and IFN-γ levels were not elevated in AR patients with or without AHR vs asthma patients.
Conclusions:  These findings suggest that VEGF and IL-5 can be important determinants of the development of AHR in AR patients and that lower levels of other cytokines may be associated with the absence of asthmatic symptoms in AR patients with AHR.  相似文献   
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