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71.
Peripheral T cells from patients with chronic active hepatitis (CAH) showed a significantly decreased suppressor effect (or increased helper effect) on allogeneic B cell differentiation into Ig-producing cells (Ig-PC) (p less than 0.05). After irradiation of T cells to eliminate suppressor influences, mean spontaneous helper activity of CAH was not different from that of healthy subjects, indicating that spontaneous helper activity of CAH was normal. Concanavalin A (Con A)-induced suppressor cell activity was significantly decreased in CAH (p less than 0.01, 9 defective cases out of 18 patients). Minor defect of Con A-induced suppressor activity was also found in some patients with chronic persistent hepatitis (CPH) (2 defective cases out of 14 patients). Autologous mixed lymphocyte reaction (AMLR) was significantly decreased in patients with CAH (p less than 0.005). Spontaneous suppressor or Con A-induced suppressor activity was not different statistically between HBsAg-positive and HBsAg-negative cases. Finally, we demonstrated a presence of a serum factor(s) that can decrease Con A-induced suppressor cell function of healthy subjects in 7 of 21 patients with CAH and 2 of 14 CPH. Our results suggest that defective suppressor cell function likely attributable to serum factor(s) may reflect altered immune responses of CAH.  相似文献   
72.
We examined whether retrograde intrabiliary adenoviral administration could induce safe and efficient transgene expression in hepatocytes. We administered recombinant adenovirus carrying a reporter lacZ gene retrogradely into the common bile duct of rats and evaluated the transduction efficiency of the lacZ gene in the liver histochemically by X-gal staining, and also quantitatively by a chemiluminescent reporter gene assay. Retrograde administration of adenovirus into the common bile duct was shown to successfully induce transgene expression in the liver. Although transgene expression induced by intrabiliary adenoviral administration was observed predominantly at periportal areas, a considerable number of cells expressing the transgene were detectable even in lobular and centrilobular areas. Furthermore, histochemical analysis revealed that intrabiliary adenoviral administration resulted in gene transfer into hepatocytes, but not into biliary epithelial cells. Transgene expression in the liver was transient, and pathological and biochemical analyses revealed that hepatic damage caused by intrabiliary adenoviral administration was not substantial. The results demonstrated in the present study suggest that retrograde administration of adenovirus into the common bile duct can induce safe and efficient transgene expression in hepatocytes without causing considerable adverse effects, supporting the feasibility of adenovirus-mediated gene transfer into hepatocytes in clinical settings by means of endoscopic retrograde cholangiography.  相似文献   
73.
To examine the feasibility of liver-directed in vivo gene therapy, we administered recombinant adenoviruses carrying a reporter lacZ gene retrogradely into the common bile duct of rats, as well as antegradely into the portal vein. Transduction efficiency of the lacZ gene in the liver was estimated not only histochemically by X-gal staining, but also quantitatively by a chemiluminescent reporter gene assay. Retrograde infusion of adenoviruses into the common bile duct was shown to successfully induce transgene expression in the liver. Transduction efficiency induced by intrabiliary adenoviral administration was not significantly different from that induced by intraportal adenoviral administration. Although transgene expression induced not only by intraportal, but also by intrabiliary adenoviral administration was observed predominantly at periportal areas, a considerable number of cells expressing the transgene were detectable even in lobular and centrilobular areas. Mild infiltration of inflammatory cells into the liver and mild hyperplastic changes of hepatocytes were observed after intrabiliary and intraportal adenoviral administration. However, hepatic damage estimated pathologically was not substantial. Furthermore, although intrabiliary and intraportal adenoviral administration resulted in very mild elevation of liver-related serum biochemical parameters, apparent complications were not observed in any rats. Our results demonstrated in the present study suggest that retrograde administration of adenoviruses into the common bile duct can induce efficient transgene expression in the liver without causing severe adverse effects, supporting the feasibility of adenovirus-mediated gene transfer into the liver in clinical settings by means of endoscopic retrograde cholangiography.  相似文献   
74.
OBJECTIVE: To characterize serial long-term histological changes in mesenchymal cells infiltrating a collagen-based matrix, as in a hollow organ with differentiated urothelial lining created intraperitoneally by grafting cultured urothelial cells, mesenchymal cells with smooth-muscle immunohistochemical characteristics infiltrated into the scaffold, despite no mesenchymal cells being seeded into the scaffold before grafting. MATERIALS AND METHODS: To regenerate a urothelial lining tissue intraperitoneally, rat urothelial cells were cultured and seeded with the feeder-layer technique onto bladder acellular matrix (BAM). After 7 days of cultivation to attach urothelial cells on the BAM, the matrix was folded with the urothelial cells inside and grafted onto the mesentery of the previously partially cystectomized rat. RESULTS: The grafted urothelial cells on the BAM, which formed a monolayer before grafting, stratified into three to four layers as early as 4 days after grafting. Although the regenerated urothelium became thinner with time, there was urothelial stratification and a peculiar angular appearance on the apical surface of the regenerated urothelium even after 56 days. The mesenchymal cells infiltrating the BAM showed positive immunohistochemical staining to alpha-smooth muscle actin or desmin at 7 days. Subsequently, the number of actin- or desmin-positive cells gradually decreased with time. On transmission electron microscopy, the infiltrating mesenchymal cells were characterized as myofibroblasts at 7 days. Smooth muscle-like cells were identified at 14 and 28 days, and fibrocytes were the main population at 56 days. CONCLUSIONS: Although epithelial-mesenchymal interactions have been assumed to be one of the most critical factors in smooth-muscle development, mesenchymal cells infiltrating the scaffold in this intraperitoneal regeneration model gradually lost smooth muscle characteristics with time. These results suggest that interactions between cultured urothelial cells and infiltrating mesenchymal cells alone could not maintain the smooth muscle character of infiltrating mesenchymal cells.  相似文献   
75.
Adrenal ganglioneuroma: a case report   总被引:1,自引:0,他引:1  
A patient with an incidentally diagnosed adrenal ganglioneuroma is reported. A 37-year-old man who underwent abdominal computed tomography (CT) in the course of evaluating liver dysfunction was found to have a right adrenal tumor. Laboratory data including results of endocrinologic tests were normal except for a slight elevation of plasma aldosterone. With a preoperative diagnosis of non-functioning right adrenal tumor, resection was performed. The tumor specimen was noncystic weighing 150 g and measuring 10 x 8 x 3 cm. The histopathologic diagnosis was ganglioneuroma originating from the adrenal gland. Adrenal ganglioneuroma is relatively rare, 147 cases including ours have been reported in Japan. Increasing numbers of these tumors are being found incidentally by ultrasonography or CT. Ganglioneuroma is a benign tumor, and disagreement exists concerning diagnosis and indications for surgery.  相似文献   
76.
77.
From March, 1984 to April, 1985, 70 cases of upper urinary tract calculi (73 renal units) were treated by percutaneous nephrolithotripsy or transurethro-ureteral lithotripsy, mainly utilizing ultrasonic lithotrite. While in the early period of treatment, two stage procedure of creation of nephrostomy tract and percutaneous nephrolithotripsy was performed for renal and upper or middle part of the ureteral calculi, one stage procedure, nephrostomy tract formation followed by ultrasonic nephrolithotripsy is commonly used in recent cases. During this period, conventional stone surgery was seen in 6 cases of pyelolithotomy and 2 of ureterolithotomy, while 52 cases of stone surgery were performed during the earlier period (from January, 1983 to February, 1984). Renal and upper or middle part of ureteral calculi were successfully removed in 49 out of 58 cases (84.5%). Most of the patients required 1 or 2 trials of percutaneous nephrolithotripsy. Middle or lower part of ureteral calculi were removed in transurethro-ureteral approach in 11 of the 12 cases. Hematuria and fever were most common complications after treatment and 3 patients required blood transfusion after 3 or 4 sessions of nephrolithotripsy. Percutaneous nephrolithotripsy and transurethro-ureteral lithotripsy are now widely used for treatment of upper urinary tract calculi, replacing the conventional surgical treatment. Moreover, very recently, extracorporeal shock wave lithotripsy is available in Japan. To the patients with renal calculi indicative of this treatment, both percutaneous nephrolithotripsy and extracorporeal shock wave lithotripsy are introduced and either way of treatment can be chosen by the patient himself.  相似文献   
78.
79.
We encountered a patient with Philadelphia-negative chronic myeloid leukaemia, with t(7;11)(p15;p15), in whom acute leukaemia phase (acute myeloid leukaemia-M2 morphology) developed within a short period. We detected a novel gene fusion between NUP98 and HOXA11 both in the chronic phase and in the acute leukaemia phase in this case. Although it is well known that a fusion of NUP98-HOXA9 in myeloid malignancies is created by the t(7;11)(p15;p15), this case suggests the possibility that HOXA11 might be another partner gene for NUP98 in t(7;11)(p15;p15) leukaemia.  相似文献   
80.
A 32-year-old man with a 1.7-cm tumor in the left kidney underwent laparoscopy-assisted partial nephrectomy. Although his postoperative course was uneventful, a 6-month postoperative CT scan showed hydronephrosis secondary to a severe stricture at the ureteropelvic junction. Heat injury to the urinary tract was strongly suspected. The use of microwave tissue coagulator for the tumor close to the renal sinus and excessive coagulation should be avoided to prevent heat-related complications.  相似文献   
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