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81.
A müllerian adenosarcomalike tumor of the seminal vesicle is described in a 49-year-old man. The tumor occupied the entire right seminal vesicle and adhered to the right lobe of the prostate, in the area adjacent to the seminal vesicle. The tumor was also adherent to the rectum. Microscopically, the cells were seen to invade the prostatic tissue. The tumor consisted of a highly cellular stroma with spindle-shaped pleomorphic cells, suggesting the diagnosis of a low-grade sarcoma. In addition, dilated cystic spaces lined by columnar epithelium were seen. Immunohistochemically, most tumor cells showed positivity for vimentin, desmin, and muscle-specific actin, suggesting smooth-muscle cell differentiation. Furthermore, electron microscopy also demonstrated smooth-muscle differentiation of the tumor cells. The patient has been disease-free for 48 months since undergoing a cystoprostatetectomy.  相似文献   
82.
Activation of the complement (C) system has been documented in both experimental and clinical studies of myocardial infarction, but the exact time course and mechanisms leading to C activation have remained unclear. Our earlier postmortem study on human beings showed that formation of the membrane attack complex (MAC) of C was associated with loss of CD59 (protectin), an important sarcolemmal regulator of MAC, from the infarcted area. The recent discovery of a rat analogue of CD59 has now allowed the first experimental evaluation of the temporal and spatial relationship between C component deposition and loss of CD59 in acute myocardial infarction (AMI). After ligating the left coronary artery in rats the earliest sign of C activation, focal deposition of C3, was observed at 2 hours. Deposition of the early (C1, C3) and late pathway (C8, C9) components in the AMI lesions occurred at 3 hours. Glycophosphoinositol-anchored rat CD59 was expressed in the sarcolemmal membranes of normal cardiomyocytes. In Western blot analysis extracts of normal rat heart CD59 appeared as a band of 21 kd of molecular weight under nonreducing conditions. Loss of CD59 in the AMI lesions was observed in association with deposits of MAC from day one onward. Our results show that C activation universally accompanies AMI in vivo. It is initiated within 2 hours after coronary artery obstruction via deposition of C3, which may be due to generation of the alternative pathway C3 convertase in the ischemic area. Deposition of C1 and late C components also starts during the early hours (2 to 4 hours) after ischemia. Subsequent loss of the protective CD59 antigen may initiate postinjury clearance of the irreversibly damaged tissue.  相似文献   
83.
BACKGROUND: The fascio-cutaneous radial forearm flap is especially suitable to rebuild the contour of the foot, but because of low natural low flow this flap lacks the beneficial effect of large muscle flaps on bypass graft flow. The aim of this study was to introduce a novel technique of flap coverage combined to vascular bypass: an internal av-fistula was created within a radial forearm flap. METHODS: Nine critically ischaemic limbs were treated with a modified radial forearm flap in the Department of Plastic and Vascular Surgery, Helsinki University Central Hospital 1998-2003. All the patients were candidates for a major amputation unless this combined operation was attempted. A two-team approach was used: the vascular surgeon performed the distal bypass and the radial forearm flap was raised by the plastic surgeon. In eight cases a femorodistal bypass was performed and in the ninth the vein graft supplied the flap directly. The internal fistula within the flap was created between the distal end of the radial artery and either the cephalic vein or the concomitant vein of the radial artery. Flow was measured during surgery. RESULTS: Vein graft flow increased significantly after the radial forearm flap anastomosis (76 vs 44 ml/min, p=0.016). The flow of both the bypass graft and the flap artery were higher with the av-fistula patent (p=0.016 and p=0.004). Graft patency was 89% at 2 years. Infection was a major cause of amputation, 1- and 2-year limb salvages being 67 and 53%. CONCLUSION: In a group of diabetic patients increased flow in a vascular bypass graft was achieved by an internal av-fistula within a radial forearm flap. This method is useful in selected cases with poor run off and large ischaemic lesions.  相似文献   
84.
中老年职工工作能力与职业因素的关系研究   总被引:4,自引:0,他引:4  
为探讨常见职业因素在中老年职工工作能力减退中所起的作用,以工作能力指数为工具,采用成组病例对照研究方法对180名工作能力减退的职工,及857名工作能力正常的职工,进行研究因素危险度的评价。结果显示,工作场所中的一些常见有害因素在研究的工作环境中更为普遍,经常暴露于粉尘,有害化学物质、噪声,振动,高温,潮湿等环境中的中老年职工发生工作能力减退的危险性增加;在易发生我伤事故的工作环境中工作也是一种有显  相似文献   
85.
Eleven piglets with haemorrhagic necrotizing pancreatitis and nine piglets with oedematous pancreatitis were imaged using a multi-breath-hold TurboFLASH (TR 6.5 ms, TE 3 ms, TI 300 ms, flip angle 8 °, three slices) pre-excited T1-weighted sequence with an IV bolus injection of gadopentetate dimeglumine (Gd-DTPA, 0.3 mmol/kg) as a contrast agent to show dynamic contrast enhancement of the pancreas by MRI. All piglets were imaged according to the same protocol before inducing the disease. Following the IV Gd-DTPA bolus, time-enhancement curve of the pancreas during haemorrhagic necrotizing pancreatitis was significantly lower than during oedematous pancreatitis. The enhancement curves for the healthy piglets and piglets with oedematous pancreatitis did not differ significantly. Each piglet served as its own control. Because the results of this initial study are similar to those obtained with contrast-enhanced CT, we conclude that our results may encourage further clinical trials, and contrast-enhanced dynamic MRI may be an alternative to the established method of CT for diagnosing acute haemorrhagic necrotizing pancreatitis. Received 12 April 1995; Revision received 16 January 1996; Accepted 18 January 1996  相似文献   
86.
Using scotopic visually evoked potentials (VEP), an objective test of concentric absolute field defects is presented. At 0.8 log units above the mean VEP threshold, the full field, the central area of 50° diameter, and the complementary peripheral field were flash stimulated. In 13 normal subjects the peripheral VEP response was larger in amplitude and shorter in latency compared to the central response. In four cases of concentric field restriction due to hysteria and malingering, the same results were found. In three cases of retinitis pigmentosa and advanced glaucoma, the peripheral VEP sensitivity was worse than the central one or no response could be found. The amount of stray light was estimated as the difference of the thresholds for central and peripheral stimulation (1.6 to 1.8 log units) in a patient with a residual central field of 20°.  相似文献   
87.
The purpose of the study was to analyse the generalisability and geographic transportability of survival estimates produced by commonly used prognostic factors. We compared the influence of tumour size, histologic grade, axillary nodal status, oestrogen and progesterone receptor contents, age at diagnosis and two prognostication schemes (the Nottingham Prognostic Index and St. Gallen criteria) in two nationwide cohorts of patients diagnosed with breast cancer in 1991–2, the FinProg (n = 2923, Finland) and the SEER series (n = 43,249, the United States (US)). Eight-year estimates of breast cancer-specific (84% versus 80%), relative (86% versus 83%), and overall (70% versus 69%) survival were slightly more favourable in the SEER than in the FinProg series, respectively. Despite differences in demographic variables and the frequency of use of adjuvant therapies and mammography screening between the series, the prognostic factors examined produced close to overlapping survival curves with similar shapes. The results suggest that quantitative survival estimates based on frequently used prognostic factors and prognostication schemes are generalisable and transportable between large, unselected cohorts of breast cancer patients.  相似文献   
88.
BACKGROUND: Reliable markers of early developing coeliac diseases are needed. Coeliac autoantibodies in the serum or Marsh I inflammation may be indicators of subsequent coeliac disease. AIM: To investigate whether determination of intestinal transglutaminase 2-targeted autoantibody deposits would detect early developing coeliac disease better than previous methods. METHODS: The study investigated patients previously excluded for coeliac disease: 25 had positive serum coeliac autoantibodies (endomysial), 25 antibody-negative had Marsh I, and 25 antibody-negative had Marsh 0 finding. Seven (median) years after baseline investigation, new coeliac cases were recorded, and small bowel biopsy was offered to the rest of the patients. Serum and intestinal coeliac autoantibodies and intraepithelial lymphocytes were assessed as indicators of developing coeliac disease. RESULTS: Seventeen patients had developed coeliac disease: 13 in the autoantibody-positive group, three in the Marsh I group and one in the Marsh 0 group. At baseline, intestinal coeliac autoantibody deposits had a sensitivity and specificity of 93% and 93% in detecting subsequent coeliac disease, CD3+ 59% and 57%, gammadelta+ 76% and 60%, and villous tip intraepithelial lymphocytes 88% and 71%, respectively. CONCLUSIONS: Endomysial antibodies with normal histology indicates early developing coeliac disease. Transglutaminase 2-targeted intestinal autoantibody deposits proved the best predictor of subsequent coeliac disease.  相似文献   
89.
Data from a six-year period were retrospectively retrieved from medical records and an intensive care unit data management system to study the impact of infections on patients with status epilepticus. Out of 161 admitted patients, 33 had a community-acquired infection and 35 acquired an infection during their hospital stay, 10 while in a ward before admission to the intensive care unit and 25 while in an intensive care unit, giving an infection rate of 42% of all admissions (68 patients). The patients with intensive care unit-acquired infection had three times longer stays in the intensive care unit than those without any infection (P<0.001), and they utilized almost four times more nursing resources than those without infections (P<0.001). Furthermore, they were more often sedated with thiopentone infusion, either alone or in combination with other drugs, than the non-infectious patients (80% vs 20%, P <0.001). Both community- and hospital-acquired infections were related to longer intensive care unit stays (P<0.001). The hospital stay of patients with hospital-acquired infection was threefold compared to that of patients without infection (P<0.001), and these patients utilized almost three times more nursing resources than those without any infection (P<0.001). Patients with infections consumed 65.5% of the intensive care unit nursing resources of status epilepticus patients. In conclusion, the infection rate of status epilepticus patients was high and nosocomial infections were associated with more severe illness, treatment escalation, prolonged hospital stay and enhanced resource utilization.  相似文献   
90.
OBJECTIVE: To compare the biocompatibility properties of a new braided biodegradable self-reinforced poly-L-lactic acid (SR-PLLA) urethral stent to the former spiral biodegradable SR-PLLA stent and the stainless steel stent in a rabbit model. MATERIALS AND METHODS: In all, 54 male New Zealand White rabbits were anaesthetized and stents inserted into the prostatic urethra, three of each kind for each sample time. The rabbits were killed after 1, 3, 6, 9, 12 or 15 months and light microscopy and scanning electron microscopy used to analyse the effects. RESULTS: The disintegration of the braided SR-PLLA stent was more closely controlled than that of the spiral SR-PLLA stent. The metallic stent induced epithelial hyperplasia and polyposis earlier than the biodegradable stents, and in these rabbits the polyposis disappeared after the disintegration process. There were no differences in the histological analyses between the biodegradable stents, whereas the metallic stents caused the strongest inflammatory reactions. CONCLUSIONS: The braided SR-PLLA urethral stent functioned well in the rabbit urethra and clinical studies are already planned.  相似文献   
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