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41.
OBJECTIVE: To investigate the effects of stellate ganglion blockade (SGB) on the internal mammary (IMA) and radial arteries (RA) in patients undergoing coronary artery bypass graft (CABG) surgery with in vivo and in vitro studies. DESIGN: Prospective, randomized trial. SETTING: University hospital. PARTICIPANTS: Thirty-seven patients undergoing CABG surgery. INTERVENTIONS: SGB was performed on 19 patients before anesthesia induction. Another group of 18 patients underwent surgery without SGB. Diameters of proximal RA, distal RA, and IMA were determined by Doppler ultrasonography before (T1) and after (T2) anesthesia induction. Control or blocked IMA and RA segments were obtained. Norepinephrine (NE) was applied to determine the contractile force of IMA and RA rings in a concentration-dependent manner. The maximal contractile response and the sensitivity of the vessels were compared. MEASUREMENTS AND MAIN RESULTS: The diameters of IMA and distal RA were statistically larger in the SGB group than those in the control group at T2. NE-induced maximum contraction was higher in the blocked RA rings than those in the control RA and blocked IMA rings. The sensitivity of IMA segments to NE was higher than that of RA segments in the SGB group. The control and blocked IMA segments showed similar sensitivity to NE. CONCLUSION: The present results show that SGB not only increases distal RA and IMA diameters but is also associated with in vitro differences, the mechanism of which remains to be elucidated. Therefore, SGB might be considered as an alternative to topical and systemic vasodilators for reducing vasospasm in patients undergoing CABG.  相似文献   
42.
In this study, we aimed to compare Cystatin C (Cys C) with other traditional glomerular filtration rate (GFR) markers and to evaluate its superiority over them in detecting early renal involvement in patients with primary hypertension. Fifty-one primary hypertensive patients and 29 healthy control subjects, who were similar in terms of age and gender, were included in the study. In all subjects serum levels of Cys C, beta-2 microglobulin, serum creatinine (SCr), uric acid, BUN, albumin; 24 h urinary levels of protein (Upro), albumin (Ualb) and creatinine were measured. The GFR was calculated according to Creatinine Clearance (CrCl), Cockcroft-Gault (CG) and Modification of Diet in Renal Disease (MDRD) formulas. The MDRD was used as the reference method. A GFR<80 mL/min/1.73 m2 was considered as the lower cut-off limit. Mean levels of the serum parameters were found to be significantly higher in the patient group than they were in the control group (p<0.05). Mean CrCl, CG, and MDRD levels were lower in patients than they were in controls but the difference was statistically significant for CG and MDRD. The serum parameter having the best correlation with MDRD was SCr (r = -0.760) in patients and Cys C (r = -0.622) in controls. However, in ROC analysis; the area under curve (AUC) for Cys C was found to be superior (AUC = 0.900) to the other markers. The CrCl was the parameter having the worst diagnostic efficiency (AUC = 0.598). As a conclusion, compared to other traditional markers, measurement of Cys C may be a better parameter to estimate GFR, especially to detect mild reductions of GFR in primary hypertensive patients.  相似文献   
43.
Intracranial abscesses are serious complications of chronic suppurative otitis media (COM). This study included 32 patients presenting with intracranial abscesses from 780 patients hospitalized for treatment of COM. The 32 patients had 59 intracranial complications. Perisinus abscess (13 of 32) was the most common intracranial abscess, followed by temporal lobe abscess (8 of 32), epidural abscess (7 of 32), cerebellar abscess (6 of 32) and subdural empyema (2 of 32). Headache (93%), fever (87%) and altered mental status (62%) were the most common presenting symptoms and signs, along with symptoms of COM. All patients were treated with intravenous antibiotics and canal wall down mastoidectomy. Cholesteatoma with granulation tissue and bony defects at the sinus plate and/or dural plate were seen in most of the patients. Gram negative bacilli and anaerobes were the most common organisms cultured from the abscesses. Three patients had neurological sequels. One patient died. The early diagnosis of these complications requires a high index of suspicion and imaging studies. A multidisciplinary and coordinated approach is important for the management of these patients.The authors did not receive any financial support for the present study.  相似文献   
44.
The purpose of this prospective study was to evaluate microsurgical thyroidectomy by comparing it with traditional thyroidectomy. Before surgery, patients were assigned either to the microscopic thyroidectomy group (MT group), with the use of the surgical microscope, or the traditional thyroidectomy group (TT group), without the use of visual magnification. Outcome measures were operative time, intraoperative bleeding and complication rates including injury to the recurrent laryngeal nerve (RLN), the external branch of the superior laryngeal nerve (EBSLN) or the parathyroid glands. Ninety-eight patients underwent thyroid surgery (58 patients in the MT group, 40 patients in the TT group). The two groups were similar in age, sex, surgical procedures and histological findings. There was no difference between the two techniques regarding the operative time and the amount of blood loss. Neither permanent nerve palsy nor persistent hypocalcemia occurred in either group. Transient nerve palsies (RLN and EBSLN) were lower in the MT group (1.7%) compared to the TT group (7.5%), but the difference did not reach statistical significance (P>0.05). Overall transient hypocalcemia was significantly lower in the MT group (1.7%) compared with the TT group (12.5%, P=0.032). If the population was restricted to total thyroidectomy, the rate of transient hypocalcemia was 4.1% in the MT group and 33.3% in the TT group, respectively (P=0.022). In conclusion, microsurgical thyroidectomy is a feasible and efficacious surgical procedure. It significantly reduces the complications without increasing the operating time in thyroid surgery procedures. A major advantage of this technique is the possibility of attaching a camera to the microscope, thereby greatly facilitating teaching.The authors did not receive any financial support for this study.  相似文献   
45.
Severs disease (calcaneal apophysitis) is a self-limiting condition seen in physically active children. Although there is controversy about the radiographic appearance, some reports propose the importance of fragmentation of the secondary nucleus in the diagnosis of Severs disease. We studied secondary nucleus of the calcaneus with ultrasonography. Twenty-one symptomatic heels of 14 children were examined. All these heels showed fragmentation of the secondary nucleus on both conventional radiograph and sonography. Ultrasonographic examination also showed 2 retrocalcaneal bursitis. Our initial data showed that sonography may be valuable in the diagnosis of Severs disease.  相似文献   
46.
Reliable, and easy to measure, immunological markers able to denote disease characteristics in multiple sclerosis (MS) patients are still lacking. We applied a multivariate statistical analysis on results obtained by measuring-by real-time RT-PCR-mRNA levels of 25 immunological relevant molecules in PBMCs from 198 MS patients. The combined measurement of mRNA levels of IL-1beta, TNF-alpha, TGF-beta, CCL20 and CCR3 was able to distinguish MS patients from healthy individuals. CXCR5, CCL5, and CCR3 combined mRNA levels identify primary progressive MS patients while TNF-alpha, IL-10, CXCL10 and CCR3 differentiate relapsing MS patients. Our results indicate that multi-parametric analysis of mRNA levels of immunological relevant molecules in PBMCs may represent a successful strategy for the identification of putative peripheral markers of disease state and disease activity in MS patients.  相似文献   
47.
The association of leukocytoclastic vasculitis and renal cell carcinoma has been rarely documented. We report a patient who presented with leukocytoclastic vasculitis involving the skin and was diagnosed later as renal cell carcinoma. After the nephron-sparing surgery, the vasculitic lesions disappeared. We also briefly review cases of vasculitis and renal neoplasms.  相似文献   
48.
Phospholipids located in the cellular membrane play a critical role in the fluid-mosaic model of membrane structure and membrane function. Evidence is mounting for the role of abnormal phospholipid metabolism in some neuropsychiatric disorders including schizophrenia. As an important essential fatty acid (EFA), omega-3 (omega-3) fatty acid series are found in large amounts in fish oil. The aim of this experimental study was to assess the changes of some of the oxidant and antioxidant parameters in the hypothalamus of rats fed with omega-3 EFA diet (0.4 g/kg/day) for 30 days. Eight control rats and nine rats fed with omega-3 were decapitated under ether anesthesia, and hypothalamus was removed immediately. Malondialdehyde (MDA) and nitric oxide (NO) levels as well as superoxide dismutase (SOD) and xanthine oxidase (XO) enzyme activities in the hypothalamus were measured. SOD activity was significantly decreased in omega-3 EFA treated group compared to control group (p < 0.014). Tissue MDA and NO levels were also decreased in omega-3 EFA treated group compared to control rats (p < 0.0001). Xanthine oxidase activity was found to be increased in omega-3 EFA treated rats when compared to the control group (p < 0.0001). Taken together, this preliminary animal study provides strong support for a therapeutic effect of omega-3 EFA in some neuropsychiatric disorders in which reactive oxygen species (ROS) are recently accused to be an important physiopathogenetic factor.  相似文献   
49.
OBJECTIVE: To test whether twin-twin transfusion syndrome (TTTS) and non-TTTS cases that were suspect but not confirmatory for developing the syndrome (non-TTTS-with-symptoms) have discordant fetal growth patterns that correlate with our previously derived algebraic relations. METHODS: In 25 monochorionic twin pregnancies, fetal growth was determined by standard ultrasonography. The difference between estimated fetal weights (dEFW) as well as the difference divided by the average of the two weights, the difference average ratio (DAR), were fitted to the predicted trends of discordant fetal growth for TTTS and non-TTTS pregnancies. The best fits were compared with the clinical data. RESULTS: Out of 13 TTTS cases, dEFW analysis correctly correlated with 8 (62%) and DAR analysis correctly with 10 (77%). Out of 12 non-TTTS-with-symptoms cases, dEFW analysis correctly correlated with 7 (58%) and DAR analysis correctly with 9 (75%). If TTTS correlated best, dEFW analysis was correct in 8/12 (67%), and DAR analysis in 10/11 (91%) cases. If non-TTTS correlated best, dEFW analysis was correct in 7/9 (78%), and DAR analysis in 9/12 (75%). The likelihood ratios of TTTS and non-TTTS were 1.9 and 0.26, respectively, with dEFW analysis, and 9.2 and 0.31 with DAR analysis. CONCLUSION: The simple algebraic relations derived to identify trends of fetal discordant growth show evidence that clinical TTTS and non-TTTS manifestations are quantifiable. The relations may contribute to future risk stratification in monochorionic twin pregnancies, e.g., by prospectively distinguishing between cases that will develop TTTS and those that will not, despite presenting with symptoms.  相似文献   
50.
Purpose: The aim of this study was to test the feasibility of isolation and culture of adult and fetal rabbit bladder smooth muscle cells (SMCs) and comparison of their interactions with different types of biodegradable biopolymers in cell culture. Methods: Bladder SMCs isolated from adult and fetus rabbits were identified by immunostaining for smooth muscle [alpha ]-actin and myosin. Growth kinetics of SMCs were estimated using population doubling time (PDT) and thymidine labeling index (TLI). Poly (D, L-lactide-co-glycolide; PLGA) copolymers were synthesized at 85:15 and 75:25 monomer ratios. The porous scaffolds prepared from these polymers were seeded with SMCs. The study compared the effectiveness of adsorbing fibronectin and fetal calf serum (FCS) on these biopolymers. The cells grown on these polymers were quantified using a neutral red uptake assay. Results: Over 90% of the 2 cell populations stained positive for SMC marker proteins. Fetal SMCs were seen to emerge from the tissue after 3 to 4 days, whereas adult SMCs were seen after 5 to 6 days. However, estimated PDT of fetal and adult SMCs was 85.2 and 54.5 hours, respectively, and TLI of adult SMCs was also higher than with fetal SMCs. Proliferation on 75:25 PLGA was better than for 85:15 and for both biopolymers; adsorption of FCS significantly affected cell attachment relative to fibronectin. Conclusions: Although fetal SMCs were shown to emerge from explants early after seeding onto dishes, doubling time and S-phase fraction of adult bladder SMCs were markedly higher than of fetal derived cells. Adsorption of serum proteins significantly enhances the attachment of both fetal and adult SMCs to biopolymers. J Pediatr Surg 38:21-24.  相似文献   
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