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11.
An investigation was conducted to clarify the relationship between orthodontic treatment and caries incidence. DMF indices from 308 orthodontically treated and 305 untreated naval recruits were compared. Contrary to expectations, there was no evidence that orthodontic treatment increases caries experience. Orthodontically treated subjects had significantly fewer diseased surfaces--a difference averaging one less diseased surface per patient. Treatment status did not generally affect the number of filled surfaces. Treated subjects had more missing teeth if first premolars were considered, but untreated subjects had more missing teeth if first premolars were not considered. No significant correlation was found between caries incidence and duration of orthodontic treatment. The epidemiologic basis and significance of these findings are discussed.  相似文献   
12.
A comatose patient on a ventilator suffered circulatory collapse while undergoing abdominal computed tomography. The computed tomography findings are presented, and the means for prompt recognition of this catastrophe are discussed.  相似文献   
13.
Color Doppler sonography in acute epididymitis and orchitis   总被引:2,自引:0,他引:2  
Clinical diagnosis of patients with acute scrotal pain is frequently imperfect. Imaging, using nuclear medicine scintigraphy and hand-held continuous-wave Doppler ultrasound devices, has been used in these patients. We retrospectively analyzed 28 consecutive patients referred for scrotal sonography, all of whom had been imaged using color Doppler sonography. Of 22 patients with confirmed diagnoses, 11 had acute epididymitis/orchitis and 11 had another diagnosis. Ten of 11 patients with acute epididymitis/orchitis had increased epididymal flow. Eight also had increased testicular flow. None of the 11 patients without acute epididymitis/orchitis had increased flow. Our data suggest that color Doppler sonography may be useful in establishing the diagnosis of acute epididymitis/orchitis. This might decrease the need for scrotal exploration. No distinction could be made among scrotal lesions in the nonacute epididymitis/orchitis group. Sensitivity was inadequate to reliably detect flow in normal testicles, a prerequisite to accurately diagnose torsion. Newly improved sensitivity may enhance the utility of color Doppler sonography in assessing patients with acute scrotal pathology.  相似文献   
14.
Although amebic liver abscess can virtually always be successfully treated medically, percutaneous drainage has been advocated recently. In 96 recently treated patients, therapeutic aspiration and percutaneous drainage were rarely needed. Most cases were correctly diagnosed by means of clinical, laboratory, and sonographic findings. Abscesses in only 13 (13.5%) patients were diagnostically aspirated. An abscess in one patient was therapeutically aspirated because the patient was responding slowly to medical therapy. No patient required catheter drainage. The key to successful amebic abscess management is medical therapy. Therapeutic drainage is rarely needed. Successfully treated patients occasionally respond slowly to medical therapy, and successfully treated amebic abscesses may enlarge or become bizarre-appearing on sonograms. This should not prompt therapeutic drainage. Diagnostic aspiration is appropriate when amebic and pyogenic abscesses are indistinguishable using clinical and imaging findings. Rare indications for therapeutic aspiration or drainage include pyogenic superinfection and large, juxtacardiac abscesses (potential intrapericardial rupture).  相似文献   
15.
OBJECTIVE: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma. SUBJECTS AND METHODS: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted. We obtained clinical follow-up data, including surgical or angiographic findings. RESULTS: In our series, 104 (18.4%) of 565 patients had arterial extravasation. Of the 104 patients, 81 (77.9%) underwent surgery, embolization, or both. The combined rate of surgery or embolization in patients with arterial extravasation was statistically higher than expected at all four institutions (p <0.001). The spleen was the most common organ injured, occurring in 277 (49.0%) of 565 patients, and arterial extravasation occurred in 49 (17.7%) of 277 patients with splenic injury. Several other visceral injuries were associated with arterial extravasation, including hepatic, renal, adrenal, and mesenteric injuries. CONCLUSION: Based on the limited reports of arterial extravasation in the nonhelical CT literature, the percentage (18%) of clinically stable patients in our study with CT scans showing arterial extravasation was higher than anticipated. This finding likely reflects the improved diagnostic capability of helical CT. Although the spleen and liver were the organs most commonly associated with arterial extravasation, radiologists should be aware that arterial extravasation may be associated with several other visceral injuries.  相似文献   
16.
To further elucidate the mechanism of impaired gallbladder emptying in diabetics with and without neuropathy, gallbladder function was assessed by ultrasonography following a medium-chain triglyceride (lipomul, 1.5 mg/kg) infusion into the duodenum and compared to that during intravenous infusion of cholecystokinin in diabetic women. Results were compared with five healthy control women. Mean (±sd) maximal percent gallbladder volume in diabetics following lipomul was reduced to 49±8% and after intravenous cholecystokinin to 47±9%, which was less than those in controls, 21±9% and 24±6%, respectively, but not significantly different. Further analysis of gallbladder emptying to lipomul differentiated two subgroups of diabetics: one subgroup (N=5) had emptying comparable to controls (responders), while the other (N=5) had very modest emptying (nonresponders). Two of the patients in the latter group had normal gallbladder emptying during exogenous cholecystokinin and their response would be compatible with visceral neuropathy. Blood levels of cholecystokinin, measured by bioassay, following lipomul and exogenous cholecystokinin were similar in controls and diabetics. Presence of diabetic neuropathy did not correlate with impaired gallbladder emptying. Follow up at 6 and 12 months of the three nonresponder diabetics revealed that no gallstones had developed and that two of them became responders to exogenous cholecystokinin. We conclude that: (1) following lipomul, about 50% of diabetics in this study have impaired gallbladder emptying, which is not strictly correlated with diabetic neuropathy; (2) this was not due to abnormal cholecystokinin release; (3) in diabetic patients with impaired gallbladder emptying another abnormality may be present in the gallbladder; and (4) impaired gallbladder contraction may not lead to gallstone formation in one-year follow-up.  相似文献   
17.
A case of spontaneous rupture of a nonparasitic liver cyst, documented by serial computed tomography scans, is reported. The patient was closely followed clinically after the rupture of the cyst and was treated conservatively, without surgical intervention. No peritonitis developed. This unusual complication of nonparasitic simple liver cysts may not always require surgery.  相似文献   
18.
J Korula  P Ralls 《Gastroenterology》1991,101(3):800-805
The effect of obliterating esophageal varices by endoscopic sclerotherapy on portal pressure was prospectively studied in 11 cirrhotic patients with variceal hemorrhage. Portal venous pressure gradient, determined as the difference between transhepatic portal and hepatic vein pressure, increased by a mean of 31.1% +/- 14.5% in 8 (73%) and decreased by a mean of 30.1% +/- 11.7% in 3 (27%) patients, with no statistically significant change overall (P = 0.1). These changes in portal venous pressure gradient occurred despite an improvement in the laboratory and clinical parameters of hepatic function. Deep abdominal sonography with color flow imaging at variceal obliteration showed patent paraumbilical veins in 6 (55%) patients, 3 of whom had decreases in portal venous pressure gradient (29%, 19%, 42.5%) at variceal obliteration. In 5 (45%) patients without patent paraumbilical veins, a statistically significant increase in portal venous pressure gradient between initial endoscopic variceal sclerotherapy and variceal obliteration was noted (P = 0.008). Rebleeding (single episode in all 4 patients, before obliteration in 3 patients) occurred in those with an increase in portal venous pressure gradient; all patients with portal venous pressure gradient decreases were nonbleeders. No correlation between changes in portal venous pressure gradient and time to variceal obliteration, number of sclerotherapy treatments, or rebleeding episodes was observed. Thus, an increase in portal venous pressure gradient was noted in the majority of patients at variceal obliteration. Although the portal venous pressure gradient decrease may be explained by a patent paraumbilical vein, the mechanism of portal venous pressure gradient increase is not clear. It is speculated that this portal venous pressure gradient increase may be caused by an increase in collateral resistance or flow or a combination of both, resulting from obliteration of esophageal varices by endoscopic sclerotherapy.  相似文献   
19.
20.
Over the past several years, we have developed a technique to assess the resectability of periampullary and pancreatic tumors using color flow sonography. This is a feasibility study to determine if sonography with color flow imaging can play a role in evaluating patients with periampullary and pancreatic tumors. This study comprises a retrospective analysis of 51 patients referred for color flow sonographic evaluation of resectability of periampullary and pancreatic neoplasm. Scanning was performed with state-of-the-art color flow sonographic systems. Vessels that were touched or occluded by tumor were categorized according to a Pancreatic Color Doppler Score. Other factors affecting resectability (metastasis, enlarged nodes) were recorded. Sonographic findings were correlated with surgical resectability and pathologic findings regarding tumor margins. The color flow study was complete technically (all index vessels visualized) in 49 of 51 patients (96%). In all, 643 of 647 vessels (99.4%) were imaged. Forty-five patients had sufficient surgical, pathologic, or clinical proof to be included in the resectability analysis. All 18 patients with circumferential tumor or vascular occlusion (Pancreatic Color Doppler Score 4 and 5) were found to have unresectable disease. All 10 patients in whom tumor did not touch (Pancreatic Color Doppler Score 0) had negative margins. All 30 patients considered to have unresectable tumors sonographically could not be resected. Patients in this category had one or more of the following: positive pathologic margins, positive nodes, liver metastasis, or not clinically resectable. Six of 15 considered resectable sonographically (40%) were unresectable for cure. Surgeons believed that color flow sonography influenced management in 10 of 45 patients (22% overall). Color flow sonography, a painless, noninvasive, and relatively inexpensive examination, may be an effective screening tool to evaluate periampullary and pancreatic neoplasms for resectability. Our data show that color flow sonography can correctly predict unresectability of periampullary and pancreatic neoplasms. Any future evaluation of imaging and management of periampullary and pancreatic tumors should include color flow sonography.  相似文献   
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