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The contributions of pharyngeal mechanical abnormalities, flow demand, and compensatory effectiveness to obstructive sleep apnea severity were determined in 82 patients. Flow demand was estimated from mean inspiratory flow on continuous positive airway pressure. Mechanical load on upper airway muscles was estimated from minimal effective continuous positive airway pressure, flow demand, and minimum flow observed during brief pressure dial downs. Compensatory effectiveness was estimated by relating polysomnographic severity and mechanical load. Mechanical load was more severe in men, in supine position, and in older and heavier patients. Higher flow demand contributed significantly to mechanical load in men and in those who are obese. At the same mechanical load, severity was independent of age, sex, or body mass index but was greater in the supine position and in REM sleep. Mechanical load accounted for only 34% of variability in severity. Eighty-two percent of patients experienced periods of stable breathing despite mechanical loads that would produce continuous cycling without compensation. I conclude that most patients can adequately compensate for the abnormal mechanics, at least part of the time. Higher flow demand contributes to severity in men and in obesity. Severity is largely due to factors other than mechanical load. Compensatory effectiveness is impaired in the supine position and in REM sleep, but not by age, sex, or body mass index.  相似文献   
13.
Objective: To assess the effect of prophylactic corticosteroids administration at 37 weeks before term elective cesarean section (CS) in reducing neonatal respiratory morbidity and admission to neonatal intensive care unit (NICU).

Methods: This randomized trial was conducted focusing on women subjected to term elective CS. Women who were eligible for the study were divided into two groups. At 37 weeks' gestation; study group received two intramuscular doses of 12?mg dexamethasone 24?h apart, while the control group given the usual care without steroids. Outcome measures were adverse neonatal respiratory outcomes (respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN)) and rates of admission to NICU.

Results: Neonates in the treatment group had lower overall incidence of respiratory distress morbidity 7.9% versus 23% when compared to the control group. The main morbidity was TTN (7% in study versus 19.6% in control group). There was significantly lower incidence of both mild and moderate degrees of respiratory distress in the study group (7 and 0.9%, respectively) compared to 17 and 5.3% in the control group. The most significant benefit of steroid administration was noted in those babies 37–37+6 weeks.

Conclusion: Antenatal administration of steroids at 37 weeks appears to be beneficial in reducing neonatal respiratory morbidity in women undergoing elective term CS.  相似文献   

14.
Emergency Radiology - Computed tomography angiographies are frequently performed in the emergency department (ED) for the assessment of cervical artery dissection (CeAD) due to the high risk of...  相似文献   
15.
A simple, cost-effective and green mucilage-capped silver nanoparticles (Mucilage-AgNPs) modified glassy carbon electrode (GC) composite was constructed for efficient and facile electrochemical oxidation of glucose for the first time. Mucilage-AgNPs were synthesized through the direct chemical reduction of Ag+ by mucilage extracted from Opuntia ficus-indica. Mucilage-AgNPs were identified and characterized using ultraviolet-visible spectroscopy, transmission electron microscopy and square wave voltammetry. Modification of the GC with AgNPs was carried out via a transfer-sticking technique with an immobilization time of 1 h. The Mucilage-AgNPs/GC composite was studied as a possible anode for glucose oxidation in a biofuel cell. The composite resulted in glucose oxidation with a current density and power density of 85.7 μA cm−2 and 25.7 μW cm−2, respectively. Glucose sensing using the Mucilage-AgNPs/GC composite was achieved successfully via two pathways: glucose oxidation and AgNP inhibition. The glucose oxidation-based sensor showed a lower detection limit of 0.01 mM and a linear range of 0.01 to 2.2 mM. The AgNPs inhibition-based sensor provides an indirect determination pathway of glucose with a detection limit of 0.1 mM and a linear range of 0.1 to 1.9 mM. AgNP inhibition is a novel pathway that could be used for determining a large number of organic and inorganic molecules. Overall, the Mucilage-AgNPs/GC is considered a pioneering composite for glucose sensing and fuel cell applications.

A simple, cost-effective and green mucilage-capped silver nanoparticles (Mucilage-AgNPs) modified glassy carbon electrode (GC) composite was constructed for efficient and facile electrochemical oxidation of glucose for the first time.  相似文献   
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Purpose

To assess the outcome of transurethral plasmakinetic vaporization (PKVP) in the management of benign prostatic hyperplasia (BPH).

Patients and methods

From August 2010 to May 2012, 60 patients with obstructive LUTS due to BPH were included in the study. All patients were evaluated by International Prostate Symptom Score (IPSS), general examination, digital rectal examination, PSA, routine laboratory examinations, pelvi-abdominal ultrasound, trans-rectal ultrasound, and uroflowmetry. Patients with Qmax of <10 mL/sec., an IPSS of >8 and a prostate volume of >40 mL underwent transurethral PKVP.

Results

Mean age of the patients was 66.8±4.5 years. The mean times of the operation, post-operative bladder irrigation, and post-operative catheterization were 63.8±13.9 minutes, 15.2±5.7 hours, and 23.9±5.2 hours, respectively. At 3 months of follow-up, there were significant reductions in the mean IPSS from 23.4±3.5 to 9.2±3.7 (P=0.4), mean PSA from 3.03±2.2 ng/mL to 1.2±1.04 ng/mL (P value=0.02), mean post voiding residual urine from 149.8±59.5 mL to 46.9±24.1 mL (P value <0.01), and mean prostate volume from 72.8±10.3 mL to 22.7±6.1 mL (P value <0.01). Also, there was a statistically significant increase in the mean Q max. from 8.7±2.4 mL/s to 19.5±3.5 mL/s (P value <0.01).

Conclusion

PKVP is an effective and safe treatment option in the management of symptomatic BPH.  相似文献   
18.
Vitamin D and calcium are involved in a wide range of proliferation, apoptosis and cell signaling activities in the body. Suboptimal concentrations may lead to cancer development. The role of phosphate in cancer metabolism is particularly relevant in breast cancer while, magnesium deficiency favors DNA mutations leading to carcinogenesis. Objectives: To determine serum levels of vitamin D, calcium, phosphorus, magnesium, and parathormone in female breast cancer patients and to assess their association with some prognostic factors in breast cancer. Design and methods: This study is done on 98 newly diagnosed female breast cancer patients and 49 age matched apparently healthy female volunteers as controls. Serum samples from all patients and controls were subjected to 25-OH Vit D, calcium, phosphorus, magnesium, and parathormone measurements. Results: In the breast cancer group, the median serum levels of 25-OH Vit D were 15 ng/ml, while it was 21 ng/ml in the control group. Levels of 25-OH Vit D and other tested minerals were significantly lower while calcium:magnesium (Ca:Mg) ratio, and calcium:phosphorus (Ca:P) ratio were significantly higher in the breast cancer group. Significant negative correlation was detected between phosphorus and calcium, ionized calcium , calcium magnesium ratio, and calcium phosphorus ratio. Conclusion: It is not only the deficient levels of Vit D and other related minerals, but the combination of the abnormal levels of all the studied parameters that might contribute to the development of cancer. Further studies with larger number of patient are needed.  相似文献   
19.
Renal allograft survival requires multiple immunosuppressive drugs. This strategy may lead to gastric complications that necessitate gastro‐protective medications, notably, proton pump inhibitors (PPI). This study aimed to compare the influence of pantoprazole and esomeprazole on serum cyclosporine trough levels (C0) in renal transplant recipients (RTR). A prospective, parallel, open‐label trial was conducted on 47 adult RTR receiving cyclosporine doses adjusted to attain trough concentrations of 100 to 150 μg/L, mycophenolate mofetil (MMF) 750 mg q12 hour and prednisolone at 5 mg daily at Nasser Institute, Cairo, Egypt from January to September 2016. Patients were randomized into the esomeprazole group (25) or pantoprazole group (22) receiving the same dose (40 mg once daily). The study outcomes included clinical signs of rejection and renal function decline, assessed by elevations in serum creatinine, caused by cyclosporine level variations in either of the two study groups. Renal function, C0 and CBC measurements were measured at baseline and monthly for 6 months. The mean C0 values were higher in the pantoprazole group than in the esomeprazole group in the sixth month only (P = .007). Serum creatinine level was lower in the sixth month than at baseline in the esomeprazole group (P = .004). There were no signs of rejection biochemical or clinical in any of the study groups. In conclusion, PPIs should be used with caution and doses should be titrated to reach the C0 targets in RTR, which is of more importance in pantoprazole than esomeprazole to avoid C0 level elevation or decline affecting the allograft function.  相似文献   
20.
The pathophysiology of irritable bowel syndrome(IBS) is not completely understood. However, several factors are known to play a role in pathophysiology of IBS such as genetics, diet, gut microbiota, gut endocrine cells,stress and low-grade inflammation. Understanding the pathophysiology of IBS may open the way for new treatment approaches. Low density of intestinal stem cells and low differentiation toward enteroendocrine cells has been reported recently in patients with IBS. These abnormalities are believed to be the cause of the low density of enteroendocrine cells seen in patients with IBS.Enteroendocrine cells regulate gastrointestinal motility, secretion, absorption and visceral sensitivity. Gastrointestinal dysmotility, abnormal absorption/secretion and visceral hypersensitivity are all seen in patients with IBS and haven been attributed to the low density the intestinal enteroendocrine cells in these patients.The present review conducted a literature search in Medline(Pub Med) covering the last ten years until November 2019, where articles in English were included.Articles about the intestinal stem cells and their possible role in the pathophysiology of IBS are discussed in the present review. The present review discusses the assumption that intestinal stem cells play a central role in the pathophysiology of IBS and that the other factors known to contribute to the pathophysiology of IBS such as genetics, diet gut microbiota, stress, and lowgrade inflammation exert their effects through affecting the intestinal stem cells.It reports further the data that support this assumption on genetics, diet, gut microbiota, stress with depletion of glutamine, and inflammation.  相似文献   
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