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31.
Background Although extrahepatic metastasis occurs rarely after hepatic resection for hepatocellular carcinoma (HCC), the prognosis of these patients is extremely poor. Predictors of extrahepatic metastasis have not been fully investigated. Methods To identify predictors of extrahepatic metastasis after resection, we retrospectively investigated 77 patients with HCC tumors >50 mm in diameter who underwent hepatic resection. We investigated correlations between postoperative extrahepatic metastasis and clinicopathologic factors as well as extrahepatic metastasis-free survival rate by log rank test and predictors of extrahepatic metastasis by univariate and multivariate logistic regression models. Results Hepatitis B surface antigen (HBs-Ag) was found in 25 (32.5%) of 77 patients, and extrahepatic metastasis occurred in 26 (33.8%). Patients with extrahepatic metastasis showed better liver function and a high occurrence of HBs-Ag positivity than those without. The 5-year extrahepatic metastasis-free survival rate was worse in patients with HBs-Ag positivity, larger tumors (≥70 mm), higher alfa-fetoprotein level (≥300 ng/mL), and lower indocyanine green retention rate at 15 minutes (ICGR15) (<15%) than in those without. By univariate logistic regression analysis, HBs-Ag positivity, larger HCC tumor (≥70 mm), lower ICGR15 (<15%), and lower preoperative lymphocyte count (<1000/mm3) were predictors of extrahepatic metastasis (P < .1). By multivariate analysis, HBs-Ag positivity was an independent predictor of postoperative extrahepatic metastasis (P = .04). Conclusions In patients positive for HBs-Ag, radiologic examination of extrahepatic organs should be performed as a part of the postoperative surveillance. Hepatitis B virus infection may promote establishment of extrahepatic metastasis.  相似文献   
32.
BACKGROUND: New diagnostic criteria for dynamic magnetic resonance (MR) imaging in prostate cancer are presented. The diagnostic usefulness of endorectal MR imaging with dynamic contrast-enhancement in localized prostate cancer and the validity of these criteria were evaluated. METHODS: Eighteen untreated patients who were suspected of localized prostate cancer were included in the study. They received endorectal dynamic MR imaging before systematic sextant needle biopsy. First. a mapping study with the findings of MR images and histopathology of biopsy specimens was performed in eight patients out of 18 to compare the difference in T2-weighted images with the endorectal coil and the body coil in the same individuals. Second, another mapping study was performed in all 18 patients by analyzing the findings of endorectal dynamic MR images. For the diagnosis of prostate cancer in MR imaging, we offered diagnostic criteria from our experience in addition to those in plain T2-weighted images from the literature. RESULTS: The overall diagnostic rates of endorectal dynamic MR imaging were 88.9% in accuracy, 100% in sensitivity, and 81.8% in specificity. In the comparison of the endorectal and body coils in T2-weighted images in eight patients, there was no difference in the diagnostic rates except for one more histopathologic false positive portion in endorectal MR imaging. In the second mapping study in 18 patients, the diagnostic rates were 92.6% in accuracy, 88.9% in sensitivity and 93.3% in specificity. Endorectal dynamic imaging raised the diagnostic sensitivity from 77.8 to 88.9%. CONCLUSION: The data demonstrated the validity of this diagnostic criteria and the diagnostic usefulness of endorectal dynamic MR imaging in localized prostate cancer.  相似文献   
33.
Intrahepatic shunt ratio was calculated from the fraction of the uptake constant and the blood background, analyzing the data of 99mTc-(Sn)-N-pyridoxyl-5-methyltryptophan (99mTc-PMT) hepatobiliary imaging by Rutland method. Shunt flow and total hepatic blood flow (THBF) were also calculated from the values for the effective hepatic blood flow (EHBF) estimated from the blood clearance technique. In 15 cases of normal volunteer, the average of the shunt ratio, shunt flow, and THBF were 18.4 +/- 5.4 (S.D.)%, 137.8 +/- 49 ml/min, and 753 +/- 83.2 ml/min, respectively. In 8 cases of chronic hepatitis, the values were 35.2 +/- 2.6%, 276 +/- 55.4 ml/min, and 794.1 +/- 119.4 ml/min, respectively. In 12 cases of liver cirrhosis, the values were 51.4 +/- 12.6%, 353.9 +/- 141.3 ml/min, and 685.6 +/- 174.8 ml/min, respectively. In cases of chronic hepatitis and liver cirrhosis, in comparison with normal cases, the values for the shunt ratio and shunt flow were significantly increased (p less than 0.001) and those for EHBF were significantly decreased (p less than 0.001), but those for THBF were not significantly altered. There was a significant inverse correlation between the shunt ratio and EHBF (r = -0.842) in all 35 cases. This method is considered to be useful for differential diagnosis, estimation of the grade of the diseases, and evaluation of pathophysiology of various diffuse liver diseases.  相似文献   
34.
Mitsuhide K  Junichi S  Atsushi N  Masakazu D  Shinobu H  Tomohisa E  Hiroshi Y 《The Journal of trauma》2005,58(4):696-701; discussion 701-3
BACKGROUND: We prospectively evaluated whether computed tomographic (CT) scanning and selective laparoscopy (LP) for the diagnosis of blunt bowel injury (BBI) could prevent nontherapeutic laparotomy and delayed diagnosis. METHODS: Between April 1994 and May 2002, hemodynamically stable patients suspected of having BBI were enrolled in this study. Patients with hemodynamic instability or solid organ injuries with hemoperitoneum were excluded. All patients underwent a physical examination and contrast CT scanning at admission and once again approximately 12 hours (range, 6-24 hours) after admission. LP was performed under general anesthesia in patients who had local peritoneal signs and indirect CT signs (bowel thickening or isolated intraperitoneal fluid) or in whom abdominal pain or tenderness increased or intraperitoneal fluid increased on the repeat CT scan. The indications for a celiotomy were diffuse peritonitis, pneumoperitoneum on the abdominal CT scan, or bowel perforation visible on LP. RESULTS: During the study period, 399 of 1,074 patients admitted for blunt torso injuries were enrolled in this study. Eleven patients underwent emergency celiotomy and 11 underwent LP immediately after admission to the emergency department. One nontherapeutic laparotomy was performed among the patients who underwent celiotomy. The LPs revealed seven bowel perforations and one mesenteric laceration. After a repeat CT scan, three and seven of the patients underwent laparotomy and LP, respectively. Four bowel perforations were found by LP. The remaining 198 patients were treated conservatively, and no complications related to a delayed BBI diagnosis occurred. CONCLUSION: CT scanning and selective LP can prevent nontherapeutic laparotomy and delayed diagnosis in patients with suspected BBI.  相似文献   
35.
BACKGROUND: An extended transsphenoidal approach allowed for direct midline exposure of the parasellar structures such as the hypothalamic-pituitary axis and the third ventricle. To evaluate the capability of this approach for removal of suprasellar craniopharyngiomas, surgical outcomes were retrospectively analyzed. METHODS: During a 9-year period, 20 consecutive patients with suprasellar craniopharyngioma underwent transsphenoidal tumor resection. The average follow-up period was 55 months. No patient had a purely intrasellar tumor, 9 had prechiasmatic tumors, 9 had retrochiasmatic tumors, and 2 had purely intraventricular tumors. RESULTS: Total resection was achieved in 86% of operations. Even in mostly intraventricular cases, a transsphenoidal trans-lamina terminalis approach afforded complete resection. Visual improvement and preservation of the pituitary stalk were achieved in 84% and 95% of cases, respectively. New postoperative deterioration of pituitary function occurred in about 65% of cases, and no patient resolved their preoperative hormonal disturbance after surgery. The overall percentage of patients with diabetes insipidus increased to 61% postoperatively from 11% preoperatively. Nonendocrinologic surgical complications were observed: worsening of vision in 3 patients, hyperphagia in 3 patients, short-term memory loss in 2 patients, and cerebrospinal fluid leakage in 3 patients. Recurrence after total resection occurred in 2 (11%) patients with retrochiasmatic tumors. CONCLUSIONS: Reasonable surgical results in this study suggest that the extended transsphenoidal approach is safe and effective for removal of craniopharyngiomas. Although preservation of the pituitary stalk can be achieved in a high percentage of patients, postoperative endocrinopathy still remains as a significant problem after radical removal of the craniopharyngioma.  相似文献   
36.
BACKGROUND: Propofol-anesthesia administerd using target-controlled infusion (TCI) has been proposed for cardiac surgery. But, moderate target concentration of propofol during induction using TCI has not been studied in detail. METHODS: Thirty patients scheduled for cardiac surgery under cardiopulmonary bypass (CPB) and TCI propofol anesthesia were randomly divided into two groups to receive a computer-controlled infusion of propofol with target concentrations of 1.5 or 2.0 micro/g x ml(-1) [1.5 microg x ml(-1) group (n=15) and 2.0 microg x ml(-1) group (n=15)]. Mean arterial pressure (MAP), heart rate (HR) and bispectral index scale (BIS) values were recorded at 5 time points during induction of anesthesia. RESULTS: MAP was significantly lower in 2.0 microg x ml(-1) group compared with 1.5 microg x ml(-1) group. In both groups, a rise of BIS value did not occur during tracheal intubation. CONCLUSIONS: We have demonstrated that propofol TCI at a target concentration of 1.5 microg x ml(-1) is effective for hemodynamic stability during induction of anesthesia in patients for cardiac surgery under CPB.  相似文献   
37.
An epidermoid cyst is a common occurrence in the skin. Such a cyst occurring in the retrorectal space, however, is extremely rare. We herein present a case of retrorectal epidermal cyst in a 67-year-old Japanese woman. She reported no symptoms and a perirectal mass behind the lower rectum was accidentally detected by computed tomography (CT). Contrast CT and magnetic resonance imaging revealed a cystic mass (76 x 70 x 63 mm) with a slightly enhanced thin wall which was attached to the lower rectum. The patient underwent surgery via a posterior approach. The mass was exposed after an excision of subcutaneous fat and was firmly adhered to the anal sphincter muscle. The cystic mass was completely removed without a proctectomy. Histologically, the cyst was diagnosed to be an epidermoid cyst. The postoperative course was uneventful, and the patient was discharged on postoperative day 9. A diagnosis of retrorectal cystic tumor is difficult, and a complete resection is necessary for the treatment of such tumors.  相似文献   
38.
To evaluate laparoscopy-assisted Billroth-I gastrectomy (LADG), we examined the outcome of its use over the last 10 years. From December 1991 to December 2001, 116 patients with early gastric cancer underwent LADG in the surgical department of Oita Medical University and Koga hospital by the same surgical staffs. An operation record and clinical sheets were reviewed to obtain the operative findings, clinical course, and pathologic findings of resected specimens to evaluate the usefulness of LADG in the management of early gastric cancer. In all LADG procedures, regional lymph nodes dissection (D1+alpha) was successfully performed using laparoscopy. The mean operative duration and blood loss were 234 minutes and 139 mL, respectively. There were only four major complications, including pneumonia, leakage of anastomosis, pancreatic injury, and anastomotic stenosis, but all these cases were successfully treated conservatively. The mean length of postoperative stay was 16.3 +/- 2.5 days. All patients except one, who died not of cancer but of cerebral bleeding, were alive without recurrence or port-site metastasis during mean follow-up period of 45 months. We successfully performed 116 LADG procedures over 10 years. This procedure is recommended for the treatment of patients with early gastric cancer because of the associated good prognosis and several benefits, including less invasiveness and early recovery.  相似文献   
39.
Development of port-site metastasis after pneumoperitoneum   总被引:7,自引:0,他引:7  
Background: Port-site metastasis is a critical problem in laparoscopic cancer surgery; the pathogenesis and means of prevention are still unclear. The aim of this study was to clarify by scanning electron microscopy the initial morphologic changes in the development of port-site metastasis. Methods: Fifteen nude mice were injected with human gastric cancer (MKN 45) cells. Mice were killed on days 0, 3, and 8 (n = 5 each day) after intraperitoneal injection of 5 × 105 cancer cells and carbon dioxide (CO2) pneumoperitoneum at 4–6 mmHg for 20 min. The abdominal wall with the port sites was harvested and examined under both light and scanning electron microscopy. Results: Immediately after CO2 pneumoperitoneum (day 0), the abdominal peritoneum was peeled away and the muscular layer was destroyed at the port site in all mice. Several cancer cells were attached to the injured port sites. On day 3, the subperitoneal tissue and muscular layer defects were replaced by granulation tissue, and several cancer cells were observed in the subperitoneal tissue. On day 8, a small nodule was macroscopically visible at the port site; it was completely covered by mesothelial cells and consisted of numerous cancer cells. Conclusions: Free cancer cells appear to attach to the injured port sites immediately after CO2 pneumoperitoneum, and these are associated with the development of port-site metastasis after laparoscopic cancer surgery.  相似文献   
40.
Introduction The effect of laparoscopic surgery under CO2 pneumoperitoneum on liver function is not clear. The aim of this study was to clarify whether laparoscopy-assisted distal gastrectomy (LADG) is associated with changes in liver function compared with open distal gastrectomy (ODG). Methods A total of 205 patients who underwent LADG (n = 147) or ODG (n = 58) between January 1994 and April 2004 were included in this study. Liver function tests—aspartate aminotransferase (AST), alanine aminotransferase (ALT), albumin, total bilirubin—were examined before surgery and at 1, 3, and 7 days after surgery. The postoperative clinical course was compared between the two groups. Results AST levels on day 1 and ALT levels on days 1 and 3 were significantly higher in the LADG group. Albumin levels showed a marked decrease after operation in both groups, but the level recovered more rapidly in the LADG group than in the ODG group, showing significant differences on days 3 and 7. The total bilirubin levels remained unchanged from baseline. The postoperative complication rate was similar in the two groups, although 3 LADG patients among the 27 patients with liver disease suffered severe enteritis. Conclusions Transient liver dysfunction was documented in patients after laparoscopic gastrectomy under CO2 pneumoperitoneum.  相似文献   
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