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101.
BACKGROUND/AIMS: Radiofrequency ablation has become a new therapeutic method for treating malignant liver tumors. We reviewed our experience to identify the factors involved in successful radiofrequency ablation therapy. METHODOLOGY: Patients who underwent this therapy between 1999 July and 2002 July were reviewed for the characteristics of their tumors, clinical data and operative techniques used. RESULTS: Sixty-one patients (hepatocellular carcinoma 50 and metastatic tumors 11) were ablated. Forty-six cases (75.4%) were ablated effectively. Survival of patients with hepatocellular carcinoma was superior to those with metastases. The effective factor was the number of nodules while the survival factors were the number of nodules and the maximum tumor diameter. Recurrence factors in patients with hepatocellular carcinoma ablated effectively were poor hepatic function due to cirrhosis and higher protein induced by vitamin K absence or antagonist-II (PIVKA-II). CONCLUSIONS: The survival of patients with hepatocellular carcinoma was significantly better than those with metastases. We recommend radiofrequency ablation therapy for cases having a single hepatic tumor less than 3.5 cm in diameter (4 cm for hepatocellular carcinoma requiring much care). In patients with hepatocellular carcinoma, hepatic function with cirrhosis and PIVKA-II showed a significant correlation with recurrence.  相似文献   
102.
BACKGROUND/AIMS: The aim of this study was to investigate whether exogenous dehydrocholic acid (DHCA) was useful to enhance the delineation of the biliary tree. METHODOLOGY: Our study population comprised 14 patients. Magnetic resonance cholangiopancreatography was acquired before and after the administration of DHCA. Two different MRCP snap shot techniques were applied: thick-slab two-dimensional (2D) (coronal) single shot turbo spin echo T2-weighted sequences and multisection thin-slab, 2D (coronal) single shot turbo spin echo T2-weighted sequences with three-dimensional (3D) maximum intensity projection (MIP) post processing. Volume rendering was prepared based on the source images, and the pixel size was visually adjusted to the biliary area of MRCP to measure the biliary tree volume. RESULTS: DHCA increased the bile duct volume in 13 of the 14 patients. It provided a better visualization of the biliary tree in 11 patients. The three patients without improvement in visualization included 1 patient with liver cirrhosis secondary to portoenterostomy for congenital biliary dilatation and 2 patients with cholecystectomy who had the bile ducts filled with bile by the time of the administration. CONCLUSIONS: It was suggested that administration of DHCA could enhance the delineation of the biliary tree on MRCP images.  相似文献   
103.
Background and Aim: We investigated the usefulness of magnetic resonance cholangiopancreatography (MRCP) and the need for endoscopic retrograde cholangiopancreatography (ERCP) in patients with clinically suspicious spontaneous passage of bile duct stones. Methods: The study population consisted of 113 patients suspected of having common duct bile stones. Of them, 50 patients were clinically suspected of spontaneous passage of bile duct stones based on the presence of gallbladder stones on ultrasound examination or a history of common bile duct stones after cholecystectomy, clinical symptoms including abdominal pain and fever associated with inflammatory reaction and marked rise of hepatobiliary enzymes which resolved or normalized after conservative treatment without evidence of stones in the common bile duct on MRCP. These 50 patients were prospectively followed up for a median of 10.2 months. Results: All patients except for one had had no symptoms related to cholangitis. Only one patient received ERCP due to recurrence of symptoms after 6 months. Conclusion: When clinical symptoms improve, hematological parameters normalize, and MRCP indicates that there are no stones in the common bile duct, it can be considered that the stones have passed naturally.  相似文献   
104.
To study injury and subsequent changes in skeletal muscles, the rat sciatic nerve was electrically stimulated at 50 Hz and muscle contraction was induced for 30 min. Muscle damage was classified into five types (hypercontraction, hyperstretching, Z band disorders, misalignment of myofilament and regions of scarce myofilaments) by electron microscopy and quantified by ultrastructural assessment. After electrical nerve stimulation, the percentages of the injured areas of the soleus muscle were 18.8 +/- 15.8% (mean +/- SD) at 0 h, 9.7 +/- 1.0% at 6 h, 22.0 +/- 23.6% at 12 h, 13.1 +/- 3.2% at 24 h, 4.9 +/- 6.0% at 3 days and 0.5 +/- 0.4% at 7 days. At 0 h, the vast majority of ultrastructural alterations were sarcomere hypercontraction. At 6 h, hypercontraction was not recognizable and sarcomere hyperstretching and Z band disarrangement constituted the major findings. At 12 h, when the injury reached its maximum, myofilament disorganization and hyperstretching were predominant. At 24 h or afterwards, the injury began to decrease and recovered to almost normal conditions by 7 days. There were very few necrotic muscle fibers in all specimens. It is considered that the muscle lesions in the present study were reversible, and recovered through changes in various types of sarcomere alterations. Z band streaming and free ribosomes were frequently found at 12 and 24 h, which may indicate repair processes rather than newly formed lesions.  相似文献   
105.
106.
The node of Ranvier in myelinated fibers is known to have an affinity to bind cations. Demyelination and remyelination due to abnormal expression of a myelin protein may affect cation binding or vice versa under pathological conditions. To study the cation binding at the node of Ranvier in inherited demyelinating neuropathies associated with over- and under-expression of the peripheral myelin protein 22 (PMP-22), the reaction with ferric ion and ferrocyanide was used to visualize the cation binding sites in biopsied nerves of four patiens with Charcot-Marie-Tooth disease type 1A (CMT1A) and two patients with hereditary neuropathy with liability to pressure palsies (HNPP), and the results were compared with those of four patients having acquired neuropathies with normal PMP-22 expression. In CMT1A, nodal widening or paranodal demyelination was associated with dense precipitates focally on both sides of the widened node. Although fainter precipitates were present at the node between remyelinated internodes, the percentage of nodes exhibiting the reaction product between normal and remyelinated internodes was not statistically different from that between normal internodes in CMT1A. In acquired neuropathies, on the other hand, the difference was significant between the two (P < 0.05), with reduction between normal and remyelinated internodes. At the nodes neighboring demylinated internodes, the percentage of nodes exhibiting the reaction product was reduced significantly in both CMT1A and acquired neuropathies, but to a lesser degree in CMT1A. Precipitates were clearly seen at the nodes neighboring a tomaculum in HNPP. The results suggest that preserved cation binding at the node may allow nerves to keep the electrical excitability in CMT1A and HNPP where myelin remodeling takes place at high frequency. Received: 6 June 1995 / Revised: 28 September 1995 / Revised, accepted: 29 November 1995  相似文献   
107.
We report on a boy with ring chromosome 7 who had severe mental retardation, growth failure, microcephaly, cleft lip and palate, café-au-lait sports, nevus flammeus, and genital abnormalities, and died of pneumonia at age 20 months. On autopsy he had fusion of the anterior cerebral hemispheres, accompanied by agenesis of olfactory bulbs and tracts, closely resembling those found in semi-lobar holoprosencephaly. In addition, heterotopic Purkinje cell cluster in the cerebellar white matter, absence of pigmentation within the brainstem pigmented neurons, and severe hypomyelination in the whole brain were noted. The patient may represent the most severe manifestation of ring chromosome 7, and this is the first detailed neuropathological report on this subject. © 1993 Wiley-Liss, Inc.  相似文献   
108.
Intussusception is quite uncommon in adults. We report a rare case of a 76-year-old man with small bowel intussusception induced by two indwelling bowel tubes, the first a jejunal feeding tube and the second an ileus tube. After complete reduction of the first intussusception caused by the jejunal feeding tube and adhesion, re-intussusception occurred due to the postoperative adhesion and ileus tube inserted into the bowel after the previous operation for intussusception. Finally, the part of the jejunum with re-intussusception and adhesion, including the place where the previous reduced intussusception had occurred, was resected. This case is a reminder that when there is no mucosal lesion other than an indwelling bowel tube or a hard adhesion/inflammation around intussusception, the patient should be operated on without delay for resection of the intussusception to prevent re-intussusception, even if the resected bowel is predicted to be long.  相似文献   
109.
The 5'-AMP-activated protein kinase (AMPK) is a key enzyme in the protection of cells during energy crisis. AMPK is a heterotrimer consisting of a catalytic α (α1, 2) subunit and two regulatory subunits, β (β1, 2) and γ (γ1-3). To elucidate the role of AMPK in thymocytes with starvation, we investigated the expression of AMPK in murine thymocytes. The main isoforms expressed were α2, β1, and γ1, of which expression increased time-dependently with starvation, together with an increase in the amount of the active form of AMPK, phospho-AMPKα. In cultured thymocytes, expression of AMPK was induced by dexamethasone, but not by a low glucose concentration in medium. Increased expression was inhibited by glucocorticoid receptor antagonist RU486. Phosphorylation of AMPKα showed an increase with low glucose concentration, but not with dexamethasone. These results suggest that increased expression of AMPK in starved mouse thymocytes is induced by an increase in glucocorticoids and that activation is induced by hypoglycemia.  相似文献   
110.

Background/Purpose

Intraductal papillary mucinous neoplasm of the bile duct (IPMN-B) is considered an uncommon tumor. The purpose of this study was to evaluate the diagnostic utility of endoscopic cholangiography (ERC) with subsequent peroral cholangioscopy (POCS) and/or intraductal ultrasonography (IDUS) for this tumor.

Methods

From December 1991 to November 2006, a retrospective analysis was made of eight patients with IPMN-B. Their clinical features and the endoscopic diagnostic strategy for POCS and IDUS were reviewed.

Results

In all the patients, ERC failed to show papillary tumors, due to coexisting mucin or biliary sludge. POCS was carried out after ERC and it showed the presence and locations of papillary tumors in all patients, except for one with a tumor in the peripheral intrahepatic bile duct (B3). IDUS was performed in seven of the eight patients; in five of these patients, intraductal protruding tumors were clearly visualized, whereas flat tumors were not identified in the remaining two patients. In one of the eight patients, endoscopic nasobiliary drainage did not remove the huge amount of mucin. Hence, this patient required subsequent percutaneous biliary drainage. Six of the eight patients underwent surgical treatment; five patients underwent a hepatic resection with or without extrahepatic bile duct resection and one underwent a pancreaticoduodenectomy. Five of the six operated patients are still alive; one patient died of gastric cancer 90 months after the operation (mean follow-up period, 45.3 months). The two remaining patients, who were considered inoperable due to major medical comorbidities, died of liver failure and cholangitis 3 and 6 months, respectively, after stent placement.

Conclusion

ERC failed to delineate intraductal papillary tumors, due to coexisting mucin. The presence and location of papillary tumors were correctly diagnosed by both POCS and IDUS, but POCS may be better than IDUS to diagnose the extent of the tumor.  相似文献   
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