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61.
62.
Tailgut cysts are unusual cystic tumors of the retrorectal space. We describe the findings of three cases. Constipation, intrapelvic fullness and low abdominal pain were the most prominent clinical manifestations. One patient developed an abscess. Ultrasound, computed tomography and MR imaging demonstrated the presacral lesions. Transabdominal excision of the tumors in two patients resulted in good outcome whereas in the patient with the abscess there was recurrence with a fistula formation.  相似文献   
63.
The incidence and prevalence of end-stage renal disease (ESRD) continues to increase, especially in the elderly population. The role of renovascular disease in contributing to ESRD is still not well defined. The objective of this study was to determine the utility of gadolinium (Gd)-enhanced magnetic resonance angiography (MRA) in evaluating elderly patients with renal insufficiency for renal artery stenosis (RAS). A 7-month prospective study conducted in a tertiary referral center evaluated 40 consecutive patients with progressive renal insufficiency (18 men and 22 women; mean age, 70 +/- 5.6 [standard deviation] years) and high clinical suspicion for renovascular disease with Gd-enhanced MRA. Digital subtraction angiography (DSA) was obtained in only those patients with significant RAS detected by MRA. Twelve patients had significant RAS. Six of these patients had percutaneous transluminal renal angioplasty (PTRA), five patients had renal artery bypass surgery, and one patient had a stent placed after PTRA. Seventy-eight renal arteries were satisfactorily evaluated by MRA. Twenty-two renal arteries were evaluated by both MRA and DSA. Of the 12 significant stenoses detected by the MRA, 11 were confirmed by DSA and 1 was confirmed at the time of surgical revascularization. It is concluded that Gd-enhanced MRA is a useful test for the evaluation of RAS in patients with compromised renal function.  相似文献   
64.
Ischemic preconditioning (IPC) and intermittent vascular control (IVC) have been shown to reduce the number of ischemia/reperfusion injuries during liver resections with the Pringle maneuver. Our study aimed to compare the beneficial effect of these two modalities in relation to the duration of normothermic liver ischemia. A group of 24 Landrace pigs with a mean body weight of 25 to 30 kg were subjected to extended liver resection of more than 65%. Although, 12 animals underwent IPC (10 minutes of ischemia and 10 minutes of reperfusion), and subsequently the Pringle maneuver was applied for 90 minutes (n= 6) or 120 minutes (n= 6). Another 12 animals underwent liver resection by IVC (20 minutes of ischemia alternated with 5 minutes of reperfusion) for 60 minutes (n = 6) or 120 minutes (n = 6) of inflow vascular control. At 90 minutes of liver ischemia, the IPC group demonstrated lower levels of asportate aminotransferase (AST) (173 ± 53 vs. 265 ± 106 IU; p =0.089) and malondialdehyde (MDA) (2.60 ± 1.03 vs. 5.33 ± 2.25 μmol/L; p =0.022) and higher liver tissue cAMP (200 ± 42 vs. 146 ± 40 pmol/g wet wt, p = 0.04) compared to the IVC group. However, no pathologic differences were observed between the two groups. By contrast, at 120 minutes of liver ischemia, IVC proved to be more beneficial, reflected by lower levels of AST (448 ± 135 vs. 857 ± 268 IU; p = 0.006) and MDA (8.33 ± 1.75 vs. 12.7 ± 4.31 μmol/L; (p = 0.045), a higher cAMP level (127 ± 10 vs. 97 ± 31 pmol/g wet wt p = 0.045), and eventually less cellular necrosis (necrosis score 1.66 ± 0.51 vs. 2.85 ± 1.16; p = 0.04) compared to the IPC group. It appears that IPC should be employed when liver ischemia is anticipated to last less than 90 minutes, followed by IVC when the liver ischemia is expected to last 120 minutes.  相似文献   
65.
Life-threatening hypophosphatemia has been reported after major liver resections with a significant impact on postoperative outcome. Regeneration of the liver may play a crucial role, but the underlying mechanism has not yet been elucidated. This study aims at assessing the effect of vascular control and resected volume of the liver on postoperative phosphorus levels. The study included 30 patients that underwent liver resection. Sixteen patients were operated on without any vascular control and 14 with selective vascular exclusion. Correlation between serum kinetics of phosphorus to resected liver volume and warm ischemia was carried out. All patients experienced low postoperative phosphorus levels. The lowest levels were observed on the second postoperative day, when 40% developed life-threatening hypophosphatemia (< or = 1.1 mg/dl). Warm ischemia and major resections aggravated hypophosphatemia compared with patients operated on without vascular occlusion and with those with minor resections. Vascular exclusion and major resections aggravate hypophosphatemia. Patients who developed hypophosphatemia < or = 1.5 mg/dl were more prone to complications and longer hospital stays compared with counterparts who had serum phosphorus levels > or = 1.6 mg/dl.  相似文献   
66.
BACKGROUND/AIMS: To study the demographics, signs and symptoms, causes, risk factors, imaging findings, bacteriologic profile, treatment and outcome of patients with splenic abscess. METHOD: The medical records of 17 patients with splenic abscess at two tertiary-care hospitals between 1989 and 1997 were retrospectively reviewed. The demographic data, physical and radiological findings, treatment, bacteriology reports and outcome of treatment were reviewed. RESULTS: The mean age of patients was 43 years (range 7-79 years). Fever and abdominal pain were the most prominent signs. Seven patients were immunocompromised, three had abscessed hydatic cysts, two were drug users and three suffered from splenic trauma, infarction, and endocarditis, respectively. No predisposing factor was identified in 2 patients. In all cases, CT demonstrated the splenic lesion(s). Staphylococcus species and Bacteriodes were the most common microbes, identified in the blood and abscess cultures. Thirteen patients underwent splenectomy, two medical therapy and two no therapy with respective survival rates of 92, 100 and 0%. CONCLUSION: Splenic abscess is a rare surgical entity encountered mostly in immunocompromised patients. CT scan is the gold standard for the definite diagnosis. Splenectomy is the treatment of choice, while medical therapy should be reserved for unusual pathogens provided that an effective antimicrobial agent is available.  相似文献   
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68.
The development of stromal sarcomas on the foci of endometriosis is extremely rare and the differential diagnosis from other tumors of myogenic, vascular, hemopoietic or epithelial origin may present great diagnostic difficulties. We investigated the clinicopathological and immunohistochemical characteristics of 4 cases of endometrial stromal sarcoma that developed on endometriotic foci of the uterus, vagina and omentum. Thye were classed as high grade (1/4) or low grade (3/4) malignant potential tumors, according to their mitotic activity. Immunohistochemically these tumors gave a positive reaction to vimentin, but were negative to desmin, smooth muscle actin, factor VIII, EMA and LCA. These characteristics permit their identification and a proper therapeutic approach.  相似文献   
69.
70.
BACKGROUND: Experimental findings have demonstrated a beneficial role of retrograde blood flow from hepatic veins that takes place during the Pringle maneuver in liver resections. The cytoprotective effect of hepatovenous back-perfusion has not been evaluated in humans. A randomized prospective study was designed to compare the response of liver cells to ischemic-reperfusion injury during the application of two different ischemic procedures: inflow versus inflow plus outflow vascular occlusion of the liver. STUDY DESIGN: Forty patients were randomly allocated to undergo liver resection using the continuous Pringle maneuver (n = 20) or inflow plus outflow vascular occlusion of the liver by selective hepatic vascular exclusion (n = 20). Liver function was assessed on postoperative days 1 to 6. Response of liver cells to I/R injury was evaluated by measuring interleukins IL-6 and IL-8 at 3, 12, 24, and 48 hours after reperfusion. Oxidative stress was assessed by measuring malondialdehyde levels. RESULTS: Both groups were comparable regarding ischemic time, operative time, and extent of liver resection. Patients in whom retrograde blood flow to the liver took place during the Pringle maneuver showed better liver function postoperatively and less severe hepatic I/R injuries compared with those undergoing liver resection using both inflow and outflow vascular occlusion. Oxidative stress was significantly lower in the Pringle maneuver group compared with the inflow plus outflow vascular occlusion group (mean [+/- SD] malondialdehyde 8 +/- 2.1 micromol/L in the Pringle group versus 14.7 +/- 1.8 micromol/L in the selective hepatic vascular exclusion group 30 min after reperfusion, p < 0.01). CONCLUSIONS: Back perfusion via hepatic veins contributes to attenuation of I/R damage during the Pringle maneuver and should be preferred if possible during liver resection.  相似文献   
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