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51.
Resistance to thyroid hormone (RTH) is caused mainly by mutations of the thyroid hormone receptor (TR) beta gene. Although, in vitro, TRalpha1 and TRbeta1 mutants exhibit similar dominant negative effects against wild-type TR, no TRalpha mutants have ever been identified in RTH patients. It has been postulated that mutations in TRalpha gene may be lethal, compensated completely by intact TRbeta or associated with phenotypic manifestations different from RTH. To investigate the consequences of mutant TRalpha1 expression in vivo, we tried to generate two different lines of transgenic mice which express a strong or a weak dominant negative mutant TR alpha1, respectively. First, we expressed betaF451X identified in a patient with severe RTH and alphaF397X, which has an identical C-terminal truncation and a similarly strong dominant negative potency to betaF451X, under the control of human polypeptide chain elongation factor 1alpha promoter. Six betaF451X-transgenic mice were born from 223 transferred embryos, giving a transgenic frequency of 2.7%. By contrast, expression of alphaF397X resulted in quite a low transgenic frequency with 0.39% of the transferred embryos bearing the transgene. Only three transgenic mice were born with no apparently overt abnormalities, of which one male produced F1 offspring. The transgenic progeny expressed alphaF397X in the testis but we did not succeed in generating transgenic mice expressing alphaF397X in multiple organs. To avoid toxic effects mediated by a strong dominant negative activity of mutant TRalpha1, we exchanged alphaF397X for alphaK389E, which has an identical missense mutation and a relatively weak transdominant potency as betaK443E identified in a patient with mild RTH. When expressed by cytomegalovirus immediate early enhancer-chicken beta-actin promoter, we did not succeed in creating alphaK389E-transgenic mice despite three independent transgene-injections. These findings define crucial in vivo functions of mutant TRalpha1s during mouse fetal development and suggest the possibility that the expression of a dominant negative mutant TRalpha1 in extensive tissues from the early embryonal stages might be lethal.  相似文献   
52.
OBJECTIVE: To evaluate the postoperative cytology of drained fluid from the pancreatic bed as a predictive indicator of local recurrence after curative (R0) resection of pancreatic cancer. SUMMARY BACKGROUND DATA: The pancreatic bed offers a common site of cancer recurrence (local recurrence), even after curative (R0) resection is performed for pancreatic cancer. If local recurrence is thereby predicted precisely, soon after surgery, we have a chance to treat it by adding radiation or some other locoregional therapy before it can grow or spread beyond the pancreatic bed. However, there have been no previous reports of cytology performed on the drained fluid after pancreatectomy. METHODS: This study includes 94 patients who had shown negative results in the peritoneal washing cytology before resection and subsequently received pancreatectomies for pancreatic tumors. They consisted of 12 benign tumors, 17 noninvasive or minimally invasive carcinomas and 65 invasive ductal carcinomas (R0 = 58; R1/2 = 7). Postoperatively, the drained fluid from the pancreatic bed was collected for 24 hours and used for cytologic examination. The cytologic results were examined in association with the histopathology of the resected tumor, patient's survival, and mode of cancer recurrence, including local recurrence. RESULTS: Patients with benign tumors or noninvasive/minimally invasive carcinomas had negative result in cytology, and none of them have died of local recurrence (limited to the pancreatic bed) to date. However, patients with invasive ductal carcinoma revealed higher cytology-positive rates: 28% (16/58) in curative (R0) resection; and 71% (5/7) in noncurative (R1/2) resection. Among 58 patients with R0 resection, the 3-year survival rate was 14% in 16 cytology-positive patients and 55% in 42 cytology-negative patients (P < 0.05). The 3-year cumulative rate of local recurrence was 85% and 23%, respectively (P < 0.05). Compared with other histopathologic parameters obtained from the resected specimens, the drain cytology was more specific in predicting the subsequent development of local recurrence. CONCLUSIONS: Drain-cytology was a quick examination that enabled us to specifically indicate both minute residual cancer and subsequent development of local recurrence even after R0 resection of pancreatic cancer.  相似文献   
53.
Abstract We investigated the incidence of recurrence after resection of small hepatocellular carcinomas (HCC) in patients infected with hepatitis C virus (HCV) to determine the appropriate surgical management of these patients. Sixty-one patients with anti-HCV antibody who underwent curative liver resection for small HCC (≦ 2.0 cm in greatest diameter) were categorized into two groups. Group 1 consisted of 27 patients with serum concentrations of type IV collagen 7S domain (7S collagen), a marker for hepatic fibrosis, < 8 ng/ml. Group 2 consisted of 34 patients with serum concentrations of 7S collagen ≧ 8 ng/ml. Serum concentration of 7S collagen correlated with the severity of active hepatitis and the degree of fibrosis in the noncancerous hepatic tissue, both of which are related to risk potential of hepatocarcinogenesis. Serum concentration of total bilirubin, aspartate aminotransferase activity, indocyanine green retention rate at 15 minutes, the proportion of patients who were Child-Pugh class B, and the proportion of patients with severe active hepatitis or cirrhosis (determined by histologic examination) were significantly higher in group 2 than in group 1. Platelet count was significantly lower in group 2. Tumor-free survival rates were not different between the groups. In group 1, nonanatomic resection was a risk factor for recurrence by univariate and multivariate analyses (odds ratio = 3.45, p = 0.040). In group 2, nonanatomic resection was not a risk factor for recurrence. In patients with small HCV-related HCC, anatomic resection is recommended when the serum concentration of 7S collagen is low (< 8 ng/ml) because the potential of hepatocarcinogenesis may be low even after the operation.  相似文献   
54.
PURPOSE: The purpose of this study was to clarify whether or not preoperative serum levels of interleukin-6 (IL-6) correlate with well-established prognostic variables (serum level of carcinoembryonic antigen (CEA), stage, histological grade, lymphatic and venous invasion) in colorectal cancer patients. PATIENTS AND METHODS: Serum levels of IL-6 and CEA were determined in 62 patients who underwent resection of colorectal cancer. The patients were divided into two groups based on a selected cut-off value: high and low IL-6 and CEA groups. RESULTS: The median serum level of IL-6 in colorectal cancer patients was significantly higher than the median level in normal controls (p = 0.0014). Multivariate logistic regression analysis showed that a high serum level of CEA is an independent predictor for a high serum level of IL-6 (odds ratio, 4.10; p = 0.046). CONCLUSION: A high serum level of IL-6 is significantly associated with a high serum level of CEA in preoperative colorectal cancer patients.  相似文献   
55.
Leigh syndrome associated with West syndrome   总被引:2,自引:0,他引:2  
Leigh syndrome (LS) (sub-acute necrotizing encephalomyelopathy) is characterized by symmetric brain lesions occurring mainly in the basal ganglia and associated with variable clinical manifestations such as hypotonia, psychomotor retardation, and feeding difficulties. Patients with LS may develop seizures. Only three patients with LS have been identified in the literature as having West syndrome (WS). We have seen 12 children with LS in the past 20 years, and noticed that as many as five of them developed WS. This report discusses five LS children with WS, comparing them with seven LS children without WS. In all five patients, infantile spasms developed after LS had become evident, in addition to other type(s) of seizures. The onset of LS in all the patients with WS was before 10 months of age. Although not statistically proven, early onset of LS, spasticity, nystagmus, apnea, poor feeding, and cardiac problems seemed to be associated with the development of WS. We were not able to conclude that certain types of symptoms or examination results of patients with LS indicated the development of WS. The association of LS with WS did not markedly influence the prognoses of the children. WS may not be a rare complication of LS, especially in infants under 12 months of age. This report is the first review of LS associated with WS.  相似文献   
56.
Endoscopic sphincterotomy for stenosis of the sphincter of Oddi   总被引:4,自引:0,他引:4  
BACKGROUND: Sphincter of Oddi dysfunction (SOD) is one of the causes of postcholecytectomy syndrome and biliary pain. Endoscopic sphincterotomy (EST) is recommended in some cases for patients refractory to conservative treatment. By the Milwaukee classification, patients with biliary pain can be divided into three groups. Group I patients show all the objective signs suggestive of a disturbed bile outflow-i.e., elevated liver function tests, dilated common bile duct (CBD), and delayed contrast drainage during endoscopic retrograde cholangio pancreatography (ERCP). Group II patients have biliary-type pain along with one or two of the criteria from group I. Group III patients have only biliary pain, with no other abnormalities. This study confirms the effectiveness of EST for the relief of symptoms in group I patients (papillary stenosis). METHODS: Between 1989 and 1999, we treated eight patients clinically diagnosed as having group I papillary stenosis by EST. Their ages ranged from 52 to 73 years. In addition to biliary pain, all patients were found to have dilated CBD, elevated enzyme levels, and delayed contrast drainage at ERCP. None of the patients had CBD stones or other causes of obstruction. Sphincter of Oddi manometry was not performed. RESULTS: EST was successfully performed in eight patients. Each patient had a very large papilla. A false orifice was found in one patient. In five patients, endoscopic cannulation of the bile duct was very difficult. The use of a long, tapered catheter and guidewire papillotomy was necessary in four patients. A precut papillotomy was performed in one patient. All patients achieved resolution of their symptoms after EST. There were no complications. The average length of the follow-up period was 26 months. CONCLUSIONS: SOD is a real entity that continues to pose a diagnostic dilemma. EST is an effective and safe modality for the treatment of papillary stenosis (group I patients). SOD manometry is not necessary before EST in group I patients.  相似文献   
57.
Abstract: Cryofiltration, which has developed from double filtration plasmapheresis (DFPP) with a cooling unit, is an on-line technique to remove cryoglobulin. We report on a patient who suffered from progressive edema and renal insufficiency caused by cryoglobulinemic membranoproliferative glomerulonephritis (MPGN), probably due to chronic hepatitis C virus (HCV) infection. To remove cryoglobulins and terminate the HCV infection, we utilized combination therapy with cryofiltration and interferon-α injection with corticosteroids. Interferon-α was capable of decreasing proteinuria but not diminishing cryoglobulin. Additional cryofiltration could remove cryoglobulin to an undetectable level. This combination therapy was partially successful to reduce proteinuria and prevent the progressive deterioration of renal function. The major adverse effects of this therapy were bleeding and myelosuppression. We conclude that this combination therapy may be effective and should be considered as treatment for cryoglobulinemic MPGN.  相似文献   
58.
Idiopathic dilated cardiomyopathy (IDC) is a myocardial disease characterised by ventricular dilatation, impaired contractility, and the symptoms of congestive heart failure. Although the causes of IDC remain uncertain, much interest has been focused on the enteroviral infection in the myocardium in the pathogenesis of this disease. Enteroviral RNA has been demonstrated in the myocardium at all stages of IDC. Recent studies using sequence analysis of enteroviral polymerase chain reaction (PCR) products have shown that the viruses detected in hearts of patients with IDC are coxsackie B. In addition, active coxsackieviral RNA replication in the myocardium has been demonstrated by strand-specific detection of viral RNA. Viral antigen has also been found in hearts with IDC by immunohistochemical techniques. In tissue culture experiments and transgenic mice, it has been shown that restricted coxsackieviral RNA replication, and not infectious virus progeny, in the myocardium can impair cardiac contractile function and lead to dilated cardiomyopathy. Coxsackieviral RNA in the myocardium can be a marker of a poor clinical outcome after partial left ventriculectomy, and might influence prognosis after heart transplantation. Therefore, there is a therapeutic need to detect replicating coxsackieviral RNA in the myocardium, and a specific therapy for coxsackie B viruses is indicated in the management of patients with virus-positive IDC.  相似文献   
59.
High-age patients have higher rates of comorbidity that are associated with a poor prognosis. It is important to correctly evaluate their preoperative status to avoid mortality. The aim of this study was to clarify whether the Charlson comorbidity index (CCI) was useful for predicting postoperative outcomes. This retrospective study collected data from 250 consecutive patients over 75 years of age. The CCI takes into account 19 comorbid conditions. Inflammation-based scores, including the Glasgow prognostic score (GPS) and the platelet to lymphocyte ratio (PLR), are other preoperative scoring systems. The relationships among these scores and postoperative outcomes were evaluated. The patients were classified according to their vital status (dead, n = 30 or alive, n = 220). Comorbidities, the presence of double cancer, and lymph node metastases were significantly different between the groups (p < 0.01, p = 0.01, and p < 0.01). In regard to the scoring systems, the CCI, GPS, and PLR were significantly different (p = 0.02, p = 0.03, and p = 0.05). Multivariate analysis identified CCI ≥ 2 (hazard ratio (HR) = 5.24, 95 % confidence interval (CI) = 1.30–12.1, p = 0.01) as a significant determinant of postoperative outcome (p < 0.01). The overall survival tended to be lower in patients with high CCI scores group (p = 0.03). The CCI was useful to predict postoperative outcomes in high-age colorectal cancer patients.  相似文献   
60.
Insulin-dependent diabetes mellitus (IDDM) is assumed to be a T cell–mediated autoimmune disease. To investigate the role of Fas-mediated cytotoxicity in pancreatic β cell destruction, we established nonobese diabetic (NOD)-lymphoproliferation (lpr)/lpr mice lacking Fas. Out of three genotypes, female NOD-+/+ and NOD-+/lpr developed spontaneous diabetes by the age of 10 mo with the incidence of 68 and 62%, respectively. In contrast, NOD-lpr/lpr did not develop diabetes or insulitis. To further explore the role of Fas, adoptive transfer experiments were performed. When splenocytes were transferred from diabetic NOD, male NOD-+/+ and NOD-+/lpr developed diabetes with the incidence of 89 and 83%, respectively, whereas NOD-lpr/lpr did not show glycosuria by 12 wk after transfer. Severe mononuclear cell infiltration was revealed in islets of NOD-+/+ and NOD-+/lpr, whereas islet morphology remained intact in NOD-lpr/lpr. These results suggest that Fas-mediated cytotoxicity is required to initiate β cell autoimmunity in NOD mice. Fas–Fas ligand system might be critical for autoimmune β cell destruction leading to IDDM.  相似文献   
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