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991.
Gut motility is modulated by adrenergic mechanisms. The aim of our study was to examine mechanisms of selective adrenergic receptors in rat jejunum. Spontaneous contractile activity of longitudinal muscle strips from rat jejunum was measured in 5-ml tissue chambers. Dose–responses (six doses, 10−7–3 × 10−5M) to norepinephrine (NE, nonspecific), phenylephrine (PH, α1), clonidine (C, α2), prenalterol (PR, β1), ritodrine (RI, β2), and ZD7714 (ZD, β3) were evaluated with and without tetrodotoxin (TTX, nerve blocker). NE(3 × 10−5M) inhibited 74 ± 5% (mean ± SEM) of spontaneous activity. This was the maximum effect. The same dose of RI(β2), PH(α1), or ZD(β3) resulted in an inhibition of only 56 ± 5, 43 ± 4, 33 ± 6, respectively. The calculated concentration to induce 50% inhibition (EC50) of ZD(β3) was similar to NE, whereas higher concentrations of PH(α1) or RI(β2) were required. C(α2) and PR(β1) had no effect. TTX changed exclusively the EC50 of RI from 4.4 ± 0.2 to 2.7 ± 0.8% (p < 0.04). Contractility was inhibited by NE (nonspecific). PH(α1), RI(β2), and ZD(β3) mimic the effect of NE. TTX reduced the inhibition by RI. Our results suggest that muscular α1, β2, and β3 receptor mechanisms mediate adrenergic inhibition of contractility in rat jejunum. β2 mechanisms seem to involve also neural pathways. Part of this work was presented as a poster at the annual meeting of the Society for Surgery of the Alimentary Tract, Orlando, FL, May 17–22, 2003, and published as an abstract in Gastroenterology 2003, 124(4):M1342.  相似文献   
992.
The indications for early endoscopic retrograde cholangiopancreatography (ERCP) in gallstone pancreatitis are unclear, and the examination is often requested or performed without substantial supporting evidence. Several trials have been performed to determine the benefit of early ERCP in pancreatitis, yet the results of these studies are inconsistent. To more closely analyze these studies, we performed an evidence-based review of the outcomes of early ERCP in gallstone pancreatitis. To obtain the best available evidence, a PubMed search using the MeSH terms “gallstones” and “pancreatitis” was performed and further refined to identify appropriate studies. We included five randomized trials, a meta-analysis, and a Cochrane Database Systematic Review in our detailed examination of the pertinent literature. Collectively, these studies suggest that early ERCP does not alter mortality in gallstone pancreatitis. In addition, few patients with mild pancreatitis benefit from the procedure, whereas some studies indicate that patients with severe pancreatitis or documented biliary obstruction may experience fewer complications if ERCP is performed. The data in the studies are confounding because of heterogeneity of the patient population and the inability to confirm gallstones in up to one third of patients. In conclusion, ERCP is not indicated for patients with mild pancreatitis. In select patients with severe disease or biliary obstruction, ERCP may be indicated. A multicenter trial designed to study the effect of early ERCP in severe pancreatitis only may provide additional useful information in patients with documented gallstones. Presented at the Postgraduate Course of the 48th Annual Meeting of The Society for Surgery of the Alimentary Tract (Digestive Disease Week 2007), Washington DC, USA, May 20, 2007.  相似文献   
993.
Background Application of linear stapling devices for extrahepatic vascular control in liver surgery has been well-established. However, the technique for use of stapling devices in hepatic parenchymal transection is not well defined. Purpose To describe the safety and efficacy of our technique for use of vascular stapling devices in hepatic parenchymal transection during open right hepatic lobectomy is the purpose of this study. Methodology We reviewed our experience with 101 consecutive open right hepatic lobectomies performed by a single surgeon between January 2003 and July 2006, in which vascular staplers were utilized for the parenchymal transection phase. Results Of the 101 patients who underwent resection, 53 (52%) were female. The mean age was 58 years. Malignant disease was the indication for resection in the majority of patients (88%). Of those with cancer, 78% (69 of 89) had metastatic colorectal cancer, 6% (5 of 89) had metastatic neuroendocrine tumor, 4% (4 of 89) had hepatocellular carcinoma, 4% (4 of 89) had cholangiocarcinoma, and the remaining 8% were other metastatic cancers. Twelve patients (12%) underwent resection for hepatic adenoma or symptomatic benign disease (FNH or hemangioma). Forty-eight patients (48%) underwent a major ancillary procedure at the time of hepatic resection. Thirty-nine patients (39%) had a nonanatomic wedge resection of a left lobe lesion, 27 patients (27%) had one or more lesions treated with radiofrequency ablation (RFA), and 6 patients (6%) were treated with a synchronous bowel resection. The median total operative time was 336 min (range 155–620 min). A Pringle maneuver for temporary vascular inflow occlusion was utilized in all cases, with a median time of 9 min (range 4–17 min). Ten patients (10%) required blood transfusion during surgery or in the postoperative period. The maximum transfusion was 2 U of packed red blood cells (PRBC) in seven patients and 1 U of PRBC in three patients. The mean nadir postoperative hematocrit was 28.2. All patients with malignant disease had tumor-free margins at the completion of the procedure. The average hospital length of stay was 6.0 days. One patient (1%) developed a clinically significant bile leak requiring a postoperative endoscopic retrograde cholangiography (ERCP). No patient required reoperation. The 30 and 60-day postoperative survival was 100%. Conclusion These findings indicate that application of vascular stapling devices for parenchymal transection in major hepatic resection is a safe technique, with low transfusion requirements and minimal postoperative bile leak. The technique allows for rapid transection of the entire right hepatic lobe in under 10 min. Short video clips of the technique will be demonstrated. Presented at the 2007 American Hepato–Pancreato–Biliary Association, Las Vegas, Nevada, April 19–22, 2007 (oral presentation/video presentation).  相似文献   
994.
The aim of this study was to evaluate the impact of enuresis nocturna on quality of life of the mothers. Mothers who have a child with monosymptomatic nocturnal enuresis (n = 28) and mothers who have a child without any health problems (n = 38) were enrolled in the study. Groups were in balance for background variables (child’s age, gender, and number of siblings; mother’s age, marital status, highest year of education completed, and occupation; presence of health insurance; and type of residence). Short-Form Health Survey (SF-36) Questionnaire, the Beck Depression Inventory (BDI), and Spielberg’s State-Trait Anxiety Inventory (STAI) were applied to all mothers. The mothers of children with enuresis had significantly lower quality-of-life scores in the SF-36 for the bodily pain (p = 0.015) and role emotional (p = 0.014) subscales. We observed significant difference between groups according to BDI; mean score was higher in mothers who have a child with enuresis nocturna (p = 0.017). There was no significant difference between groups according to the STAI. Significant differences according to bodily pain and role emotional subscales of SF-36, and the BDI scores, show that the mothers were negatively affected by having a child with monosymptomatic nocturnal enuresis.  相似文献   
995.
The aim of this study was to compare the operative results in regard to reducing anastomotic leakage and stricture formation using a newly designed layered manual esophagogastric anastomosis versus a stapler esophagogastrostomy versus the conventional hand-sewn whole-layer anastomosis after resection for esophageal or gastric cardiac carcinoma. From January 2004 to September 2006, a total of 1024 patients with esophageal or gastric cardia carcinoma underwent a layered esophagogastric anastomosis with the assistance of a three-leaf clipper in a single university medical center. The mucosal layers of the esophagus and stomach were sutured continuously with 4/0 Vicryl plus antibacterial suture (polyglyconate). From May 2002 to December 2003, there were also 170 patients and 69 patients who underwent stapler and conventional whole-layer anastomosis, respectively; they served as control groups. The results were analyzed retrospectively. The operative mortality rate was 0.7% in the layered group compared to 5.9% and 7.2% for the stapler group and the whole-layer group (p < 0.01), The anastomotic leakage rates were 0%, 3.5%, and 5.8% for the layered group, stapler group, and whole-layer group, respectively (p < 0.01). All patients were followed postoperatively. Six patients in the layered group (0.6%) developed mild stricture formation compared to 16 patients in stapled group (9.9%) and 5 patients in the conventional whole-layer group (7.8%) (p < 0.01). The application of layered esophagogastric anastomosis could reduce the incidence of anastomotic leakage and stricture after esophagectomy compared with the stapler and whole-layer manual anastomoses. It is easy to apply and could be used as an alternative for esophagogastric anastomosis after resection for esophageal or cardiac carcinoma. This abstract was accepted as a free paper and oral presentation at International Surgical Week 2007, Abstract 320, Montreal, Canada, August 2007  相似文献   
996.
Free-radical generation and nitric oxide (NO) generation were detected in the rat bladder following acute bladder outlet obstruction (BOO), and the results were compared with those for vascular ischemia and reperfusion (I-R). Forty male Sprague Dawley rats were used. In the acute BOO plus I-R group (group 1), rats were catheterized with a 3-Fr catheter and an inflated balloon was positioned at the bladder neck. The bladder was overdistended after administration of Ringer solution and furosemide (12 mg/kg, each) for 60 min, and was then drained to allow reperfusion for 30 min. In the acute BOO plus nerve stimulation group (group 2), the pelvic nerve was stimulated in the distended bladder for 60 min (5 s every 5 min, 10 V/0.1 ms, 20 Hz). Pelvic nerve stimulation was performed in nonobstructed animals in group 3. In the I-R group (group 4), the distal aorta was occluded for 60 min followed by reperfusion for 30 min. Sham-operated animals served as the control group (group 5). At the end of the protocols, the levels of hydroxyl and superoxide radicals and NO levels were measured in the bladder tissues with luminol- and lucigenin-enhanced chemiluminescence methods. The results were compared by a one-way analysis of variance test. The levels of hydroxyl radicals were not significantly different between the study groups. In contrast, superoxide radicals and NO levels were significantly increased in both group 1 and group 4 compared with those in control animals (P < 0.05 for all comparisons). Superoxide radical generation in group 2 was comparable to the levels in group 1 (P > 0.05), whereas NO levels were substantially lower than in group 1 (P = 0.06). In summary, vascular I-R causes significant oxidative damage to the bladder. Acute BOO with overdistension of the bladder mimics the effects of true vascular I-R injury. The NO pathway has possibly a major role in I-R-induced bladder damage. Prolonged BOO may therefore significantly enhance the oxidative damage to the bladder and further accentuate the effects of generalized atherosclerotic processes in the elderly adult.  相似文献   
997.
The short bowel syndrome (SBS) can result from a variety of conditions, including postoperative complications and malignancy. Continence-preserving operations are generally performed for either ulcerative colitis (UC) or familial polyposis (FAP). These procedures can be associated with high morbidity and the potential for future malignancy. Our aim was to determine the causes and consequences of SBS in patients undergoing these procedures. Twenty-four patients (12 men and 12 women) 18 to 64 years of age were identified with SBS after continence-preserving procedures. Eighteen had pelvic procedures, and six had continent ileostomies. All SBS patients had a proximal ostomy. Remnant length measured <60 cm in five patients, 60–120 cm in ten patients, and >120 cm in nine patients. Overall 13 patients required long-term PN. Four FAP patients with desmoid tumors died. One patient with UC underwent intestinal transplant and expired. Follow-up ranges from 6 to 192 months. Overall 14 patients had UC, nine had FAP, and one had functional disease. Eight patients with an initial diagnosis of UC had subsequent Crohn’s disease necessitating further resection and pouch excision. Eight patients (five with UC, two FAP, and one with functional disease) had postoperative complications, including obstruction or mesenteric ischemia requiring resections. One UC patient developed adenocarcinoma in a continent ileostomy. Seven of the nine FAP patients required resection for desmoid tumors. Six of these underwent resection alone. Three died at 10, 11, and 13 months after SBS from liver failure and sepsis while awaiting transplant. One patient has recurrent desmoid at 30 months, another is alive and well at 48 months, and the other patient, who was not a transplant candidate, died from an unrelated cardiac operation at 23 months. A single patient underwent resection with simultaneous multivisceral transplantation. SBS can develop after continence-preserving procedures. This occurs with inflammatory bowel disease when unsuspected Crohn’s disease is present or complications occur. SBS related to desmoid tumors has a poor prognosis in patients undergoing resection alone. A more aggressive approach to intestinal transplantation in these patients may be warranted.  相似文献   
998.
Background Cytoreduction with hyperthermic intraperitoneal chemoperfusion (HIPEC) has an established role in selected patients with peritoneal carcinomatosis (PC). We analyzed the safety and efficacy of HIPEC using high-dose oxaliplatin, a cytotoxic agent commonly used in metastatic colorectal cancer and showing promising activity in ovarian cancer and mesothelioma. Methods Following complete cytoreduction, HIPEC was performed using 460 mg/m2 oxaliplatin in 5% dextrose for 30 min at a temperature of 41–42°C. Open perfusion (coliseum technique) was performed in all patients. Metabolic, electrolyte, and hemodynamic changes were recorded during chemoperfusion as well as postoperative morbidity, mortality, late toxicity, and survival. Results From July 2005 to January 2007, 52 patients were treated. Chemoperfusion with 5% dextrose resulted in temporary significant hyperglycemia, hyponatremia, and metabolic acidosis. Major morbidity developed in 24% of patients, while 30-day mortality did not occur. One patient developed unexplained repeated episodes of hemoperitoneum. Chemoperfusion with oxaliplatin resulted in mild hepatic toxicity evidenced by persistent elevation of glutamyl transferase and alkaline phosphatase 1 month after surgery. After a mean follow-up time of 14.5 months, nine patients died from disease progression. In colorectal cancer patients, actuarial overall survival was 80% at 1 year. Conclusion Cytoreduction with HIPEC using high-dose oxaliplatin leads to manageable metabolic and electrolyte disturbances and frequent mild hepatic toxicity without discernible impact on postoperative morbidity. Longer follow-up in a larger patient cohort will be required to assess the real risk of unexplained hemoperitoneum observed in one patient, and to establish the long-term effect on local relapse and survival.  相似文献   
999.
Henoch-Schönlein purpura (HSP)-associated stenosing ureteritis represents a rare complication of the disease, typically presenting with severe manifestations. This article reports on a 3.5-year-old boy with HSP and severe nephritis who developed a unilateral stenosing ureteritis with atypical manifestations, resulting in a nonfunctional kidney and consequent nephrectomy. The urinary tract ultrasound was normal in the first week of illness, and the diagnosis was made during follow-up 8 months after onset. The predominance of nephritic manifestations may have masked any signs of ureteritis, leading to the delay in diagnosis. To clarify the clinical spectrum of this complication, an extensive review of the literature was performed. We emphasize the necessity of repeated urinary tract ultrasound both early and later in the course of HSP, especially in cases with renal involvement, so that an early diagnosis of this complication can prevent a potentially serious renal outcome.  相似文献   
1000.
The gold standard procedure for the evaluation of vesicoureteral reflux (VUR) is the radiographic voiding cystourethrography (VCUG); direct radionuclide voiding cystography (DRVC) is an alternative method for detecting VUR. A new imaging procedure, voiding urosonography (VUS) with contrast medium, has recently been introduced. We have carried out a comparative study of these three techniques in 157 patients (aged 6 weeks–4.7 years). VUS showed the presence of VUR in 91 of 311 renal units; VCUG detected reflux in 64 of 233 renal units, and the DRVC in 23 of 78 renal units. VCUG and VUS were compared in 118 patients, and both procedures showed the same grade of reflux in 56 refluxing units (kappa value 0.92); in six cases the reflux grade was greater at VUS than at VCUG. Seven cases of reflux detected by VUS were not identified on VCUG. VCUG did not show a grade of VUR that was higher than in VUS in any patient. In the identification of 4°–5° grade reflux, the sensitivity of VUS reached 100%. VUS and DRVC were found to be equally effective in the detection of VUR (kappa value 0.85). In conclusion, we found that VUS is a useful method for the diagnosis and grading of patients with VUR.  相似文献   
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