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11.
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目的:检测γ-氨基丁酸(gamma-aminobutyricacid,GABA)和谷氨酸脱羧酶(glutamicaciddecarboxylase,GAD)在大鼠降结肠上皮的表达及分布特征,并探讨GABA与上皮细胞分化增殖的关系.方法:用免疫荧光及激光共聚焦显微扫描技术,检测GABA、GAD65及GAD67在大鼠降结肠上皮中的表达,并以麦芽凝聚素组织化学染色与免疫荧光结合的双重染色显示GABA和GAD65表达细胞的分布特征.同时,用RT-PCR和原位分子杂交方法检测GADmRNA的表达.此外,用3H-胸腺嘧啶放射自显影法显示降结肠上皮的增殖带.结果:RT-PCR显示降结肠黏膜中GAD65及GAD67mRNA均阳性,原位杂交显示阳性杂交信号主要分布在上皮细胞的隐窝和腔面,且GAD65信号较GAD67强.GABA及GAD65免疫反应阳性细胞主要分布在降结肠的腔面和隐窝的上1/3上皮细胞的胞质,而GAD67阳性细胞仅分布腔面,此外,GABA及GAD65阳性染色也见于黏膜固有层.双重染色显示杯状细胞中GABA及GAD65均阴性.3H-胸腺嘧啶标记阳性细胞主要在隐窝的中下段.结论:GABA及GAD65分布在大鼠降结肠上皮的成熟带及功能带,GABA系统可能参与上皮细胞的分化与增殖的调节.  相似文献   
13.
BACKGROUND: Salt status plays a pivotal role in angiotensin-II-induced organ damage by regulating reactive oxygen species status, and it is reported that reactive oxygen species activate mineralocorticoid receptors. METHOD: To clarify the role of reactive oxygen species-related mineralocorticoid receptor activation in angiotensin-II-induced cardiac dysfunction, we examined the effect of the following: salt status; an MR antagonist, eplerenone; and an antioxidant, tempol in angiotensin-II-loaded Sprague-Dawley rats. RESULTS: Angiotensin-II/salt-loading elevated blood pressure, and neither eplerenone nor tempol antagonized the rise in blood pressure significantly. Left ventricular diastolic function was monitored by measuring peak velocity of a mitral early inflow (E), the ratio of mitral early inflow to atrial contraction related flow (E/A), deceleration time of mitral early inflow and -dP/dt, the time constant (T), and filling pressure (left ventricular end-diastolic pressure) by echocardiography or cardiac catheterization. Despite the suppressed serum aldosterone, left ventricular diastolic function was deteriorated with angiotensin II/high salt, but not affected by angiotensin II/low salt. However, angiotensin-II/salt-induced cardiac dysfunction was restored by eplerenone and tempol. Nicotinamide adenine dinucleotide phosphateoxidase-derived superoxide formation was greater in the hearts of the angiotensin II/high-salt rats than of the angiotensin II/low-salt rats. The expression of the Na(+) -H(+) exchanger isoform 1, a target of mineralocorticoid receptor activation, was significantly increased in the angiotensin II/high-salt group. Both tempol and eplerenone inhibited the angiotensin-II/salt-induced upregulation of Na(+) -H(+) exchanger isoform 1. CONCLUSION: These findings demonstrate that mineralocorticoid receptor activation by oxidative stress can cause left ventricular diastolic dysfunction in a rat model of mild hypertension.  相似文献   
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Colloid osmotic pressure (COP) is important in calculating vascular permeability during hemodialysis (HD). However, few reports have directly measured COP in HD patients. Therefore, the currently published formulas may not be clinically optimal for predicting COP for HD patients. Here, the study aims were (i) to directly measure COP in HD patients and compare the measured and predicted COP values using four previously reported formulas, and (ii) to develop a formula for approximating COP using clinical parameters. We obtained 212 measured COP values using an osmometer; the average value was 22.0 ± 0.2 mm Hg. The predicted COP based on the four different formulas was positively correlated with the measured COP (0.87 < r < 0.89), but was significantly overestimated compared to it (P < 0.001). We also performed a stepwise analysis using serum albumin and non‐albumin protein concentrations and obtained the following simple formula for COP approximation: COP (mm Hg) = ?7.91 + 5.64 × albumin (g/dL) + 3.00 × non‐albumin proteins (g/dL). A positive linear correlation was observed between the measured COP and approximated COP using this formula (r = 0.90, P < 0.001). We calculated the mean Kr (plasma‐refilling coefficient) as a marker for determining dry weight in HD patients using the measured COP and approximated COP. No differences were observed between the mean Kr derived from the measured and approximated COP. We report here significant differences between measured and predicted COP values, and have devised a simple formula for COP approximation in HD patients.  相似文献   
16.
Pancreatic schwannoma is a very rare tumor that tends to be confused with other pancreatic tumors preoperatively. We report a case of schwannoma of the pancreatic head. A 40-year-old woman was admitted to our hospital for treatment of a pancreatic tumor which was found by medical checkup. It was a well-defined solid tumor exhibiting heterogeneous enhancement with some necrotic foci on contrast-enhanced computed tomography (CT) and on magnetic resonance imaging (MRI). Angiography and CT during arteriography revealed the main feeding arteries of the tumor to be the posterior and anterior superior pancreaticoduodenal arteries. Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) showed accumulation of FDG in the tumor with a maximum standardized uptake value of 3.6. We diagnosed a solid pseudopapillary neoplasm or a pancreatic neuroendocrine tumor preoperatively and performed pylorus-preserving pancreaticoduodenectomy. The tumor had well a well-defined capsule and was composed of a large solid portion containing spindle cells and a smaller hemorrhagic portion containing hypocellular stroma, and diagnosed as pancreatic schwannoma by immunohistochemistry. In this case, CT during arteriography was useful in determining the origin of the tumor. MRI reflected the pathological features of the tumor. The most important finding was that FDG-PET showed abnormal accumulation of FDG in the benign pancreatic schwannoma.  相似文献   
17.
The aim of this study was to measure exercise-induced changes in knee joint laxity in patients with knee osteoarthritis (OA). The study subjects were 46 female patients with OA and 22 age- and sex-matched normal controls. Radiographs of the knee were taken in all subjects, and the disease severity was graded according to the Kellgren and Lawrence (K-L) grading system. The K-L grade of the control subjects (non-OA group) was 0-1. The OA patients were divided into those with mild OA (K-L grade 2, n = 20) and advanced OA (K-L grade 3-4, n = 26). The subject climbed up and down 8 steps on a staircase apparatus over a period of 10 min. The anteroposterior (A-P) translation was measured with KT2000 arthrometer, and varus-valgus (V-V) rotation was measured on stress radiographs before and after the stair climbing. The Δchange in A-P translation after the exercise was significantly larger in mild OA group than other groups (P < 0.005). The Δchange in V-V rotation after exercise was significantly larger in mild and advanced OA groups than the control (P < 0.003). There were no significant differences in A-P laxity and V-V laxity before exercise among the non-OA, mild OA and advanced OA groups. Exercise resulted in significant changes in A-P knee joint laxity in patients with mild OA relative to the control. The results suggest that daily physical activities (e.g., knee bending or squatting) play a role in the development of knee laxity, particularly in patients with mild OA, and that progression of knee OA seems to correlate with increments of A-P knee joint laxity.  相似文献   
18.

Background

Postoperative hyperperfusion may lead to severe neurological complications after superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis. However, there are no reliable modalities to predict the occurrence of postoperative hyperperfusion during surgery. The purpose of this study is to evaluate whether a semiquantitative analysis of indocyanine green (ICG) videoangiography could be useful in predicting postoperative hyperperfusion after STA-MCA anastomosis.

Methods

This study included seven patients who underwent STA-MCA anastomosis due to occlusive carotid artery diseases. During surgery, ICG videoangiography was performed before and after bypass procedures, and ICG intensity–time curves were semiquantitatively analyzed to evaluate hemodynamic changes by calculating maximum intensity, time to peak (TTP), and blood flow index (BFI).

Results

Maximum intensity significantly increased from 252.6?±?132.5 to 351.7?±?151.9 after bypass (p?<?0.001). TTP was significantly shortened from 12.9?±?4.4 s to 9.8?±?3.7 s (p?<?0.001). Furthermore, BFI significantly increased from 33.9?±?28.1 to 74.6?±?88.4 (p?<?0.05). Postoperative hyperperfusion was observed in five of seven patients 1 day after surgery. The ratio of BFI before and after bypass procedures was significantly higher in patients with postoperative hyperperfusion than those without, 2.5?±?1.1 and 1.5?±?0.4, respectively (p?=?0.013).

Conclusions

These findings suggest that semiquantitative analysis of ICG videoangiography is helpful in predicting occurrence of hyperperfusion after STA-MCA anastomosis in patients with occlusive carotid artery diseases.  相似文献   
19.

Background

Quality of life (QOL) is a concern for patients with lumbar spinal stenosis (LSS). In this study, QOL was examined using the 5-item EuroQol (EQ-5D).

Methods

QOL and activities of daily living (ADL) were surveyed for 91 patients who visited 18 medical institutions in our prefecture and were diagnosed with LSS-associated intermittent claudication. A second survey was performed after ≥6 weeks for 79 of the subjects to evaluate therapy with limaprost (an oral prostaglandin E1 derivative) or etodolac (an NSAID). Symptoms, maximum walking time, QOL, ADL items, and relationships among these variables were investigated for all 91 patients. Leg pain, leg numbness, and low back pain while walking were surveyed by use of VAS scores (0–100).

Results

Leg pain, leg numbness, and low back pain while walking (VAS ≥25) were present in 83.5, 62.6, and 54.9 % of the patients in the first survey, and approximately half of the patients had a maximum walking time <15 min. The mean EQ-5D utility value for QOL was 0.59 ± 0.12. This value was significantly associated with maximum walking time (p = 0.030) based on classification of patients into groups with walking times <7.5, 7.5–15, 15–30, and >30 min, showing that maximum walking time affected health-related QOL. Of the 79 patients who completed the second survey, 56 had taken limaprost and 23 (control group) had received etodolac. Limaprost improved possible walking time, reduced ADL interference, and significantly increased the EQ-5D utility score, whereas no significant changes occurred in the control group. Maximum walking time was prolonged by ≥10 min and the EQ-5D utility value was improved by ≥0.1 points in significantly more patients in the limaprost group than in the control group.

Conclusion

According to the findings of this survey, at an average of 8 weeks after administration limaprost improved symptoms, QOL, and ADL in LSS patients whereas treatment with an NSAID reduced pain but did not have any other effects.  相似文献   
20.
This report describes case series of the femoral head fractures associated with fracture-dislocation of the hip joint to evaluate the mid- and long-term outcomes and to highlight the surgical technique of fixation of the femoral head from the posterior trochanteric flip osteotomy approach. Twelve patients (6 men and 6 women) with dislocated femoral head fractures (mean age at the time of injury, 56 years; range, 23–80) were followed up for mean period of 9.7 years (range, 5–20). All dislocations were reduced within less than 6 h after the injury. The type of femoral head fracture was classified according to the Pipkin classification on radiographs and CT. Five patients were classified as type I, 2 as type II, 2 as type III, and 3 as type IV. The clinical and radiological outcomes were assessed by Thompson and Epstein’s regimen. Excluding 2 patients with Pipkin type III, the outcome of 9 patients was excellent/good, and poor in 1. The latter patient sustained Pipkin type IV and developed osteoarthritis 1 year after surgery and consequently required total hip arthroplasty. We conclude that small fragment of the femoral head less than 1 cm can be removed, while larger fragments should be fixed by bioabsorbable screws or pins in all types of femoral head fractures. In Pipkin type IV fractures, surgeons should always take anatomical reduction in the acetabulum into consideration during surgery.  相似文献   
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