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61.
The effects of cryopreservation on human hepatocytes obtained from different sources of liver tissue
Terry C Mitry RR Lehec SC Muiesan P Rela M Heaton ND Hughes RD Dhawan A 《Cell transplantation》2005,14(8):585-594
Successful cryopreservation of human hepatocytes is important to establish hepatocyte banks for clinical use or in vitro research. The availability of donor tissue from unused liver segments/lobes and non-heart-beating donors (NHBD) has provided newer sources of hepatocytes. The quality of hepatocytes at the time of cryopreservation is important as cells isolated from liver tissue of borderline quality may not withstand the stresses associated with cryopreservation and subsequent thawing. Human hepatocytes were cryopreserved after isolation from mainly donor tissues (n = 40). In vitro assessment of the viability and function of the fresh and thawed cryopreserved hepatocytes was performed. Viability, attachment efficiency, enzyme activity, and albumin production of hepatocytes were all significantly decreased, and LDH leakage significantly increased, on thawing after cryopreservation. The viability of cryopreserved hepatocytes isolated from tissue rejected for orthotopic liver transplantation (36 +/- 15%) was significantly lower than those isolated from tissue where part was used for liver transplantation (47 +/- 14%, p = 0.002), but there were no significant differences in functional parameters. The viability of cryopreserved hepatocytes isolated from NHBD tissue (29 +/- 9%, p = 0.001) and from steatotic donor tissue (35 +/- 11%, p = 0.019) was significantly lower than those isolated from normal donor tissue (49 +/- 14%). There was no difference in functional parameters, except for albumin production of hepatocytes from NHBD tissue (2.9 +/- 1.0 microg/h/mg protein) being significantly lower than those from normal donor tissue (4.8 +/- 2.8 microg/h/mg protein, p = 0.03). The viability and attachment efficiency of cryopreserved hepatocytes isolated from liver tissue from resections for tumors was significantly higher, and the LDH leakage significantly lower, than those isolated from all donor tissue. Hepatocytes isolated from NHBD and steatotic tissue were more vulnerable to the effects of cryopreservation. Further research is required to improve hepatocyte isolation and cryopreservation protocols for different types of liver tissue. 相似文献
62.
Robert Sabbagh Suman Chatterjee Arun Chawla Anil Kapoor Edward D. Matsumoto 《Canadian Urological Association journal》2009,3(1):22-30
Background
Performing a laparoscopic urethrovesical anastomosis (LUA) after a radical prostatectomy is technically challenging for the novice laparoscopic surgeon. We developed a low-fidelity urethrovesical model (UVM) to allow a urologist to practise this critical step. The aim of our study was to compare the effect of task-specific bench model training (anastomotic suturing on the UVM) with that of basic laparoscopic suturing on intracorporeal urethrovesical anastomosis performance.Methods
We recruited 28 senior surgical residents, fellows or staff surgeons for this prospective, single-blinded, randomized controlled study. We randomly assigned participants to an intervention group practising LUA on the UVM or to a control group practising basic laparoscopic suturing and knot-tying on a foam pad. After practising, we videotaped participants performing 5 intra-corporeal interrupted sutures on a foam pad and a LUA on the UVM. A blinded expert scored the videotaped performance using a laparoscopic suturing checklist (CL) and a global rating scale (GRS), and timed the performance.Results
On the foam pad suturing task, the group that trained on the UVM had significantly higher CL scores (10.9 v. 8.1, p = 0.017). On the LUA task, the group that trained on the UVM had significantly higher CL scores (10.9 v. 8.1, p = 0.017), GRS (29.6 v. 22.8, p = 0.005) and shorter times (27.6 v. 38.3 min, p = 0.004) than the control group.Conclusion
Our task-specific bench model was shown to be superior to basic laparoscopic suturing drills on a foam pad. 相似文献63.
Usoh F Hingorani A Ascher E Shiferson A Tran V Marks N Jacob T 《Annals of vascular surgery》2009,23(3):350-354
The short-term effectiveness and safety placement of superior vena cava (SVC) filter in the treatment of upper extremity deep venous thrombosis in patients with contraindication to anticoagulation have been well documented. However, as opposed to the numerous reported experiences with inferior vena cava filter placement and its complications, there has been no documented long-term follow-up on SVC filter placement. We, therefore, reviewed our experience with SVC filter placement. A retrospective review was performed of the 154 cases of patients who underwent SVC filter placement between January 1994 and August 2005 at our institution. Seven additional patients had unsuccessful SVC filter placement due to widespread deep venous thrombosis. The data were evaluated for both insertion complications (pneumothorax, hemorrhage, filter misplacement) and long-term complications (pulmonary embolism, migration, caval occlusion). The follow-up included review of serial chest radiographs to evaluate for filter migration in patients who lived at least 60 days after filter insertion and had chest radiography performed (n = 40), patients' charts, clinic visits, and telephone contacts, hospital databases, city death records, and national databases. There were 69 males and 85 females with a mean age of 73.6 years (range, 16-96 years; +/-15.3 [SD] years). Follow-up ranged from 1 day to 3750 days (256.3 +/- 576 days [mean +/- SD]) and 5 patients were lost to follow-up. Of the 154 patients, 58 survived longer than 60 days with mean follow-up of 628.4 days. All SVC filters (TrapEase, n = 38; Greenfield, n = 116) were successfully deployed in the 154 patients. During the follow-up, 114 (74.0% mortality) of the patients died of chronic illness or from cancer complications. There were three cases of pericardial tamponade (1.9%), and one case of misplaced filter in innominate vein. There were no known cases of symptomatic pulmonary embolism, caval occlusion, pneumothorax, or filter migration. SVC filter placement is associated with a low incidence of complications with long-term follow-up. These data help to reaffirm the safety and effectiveness of SVC filter placement. However, SVC perforation in young males remains a significant issue. 相似文献
64.
Lumbar spinal fusion is advancing with minimally invasive techniques, bone graft alternatives, and new implants. This has
resulted in significant reductions of operative time, duration of hospitalization, and higher success in fusion rates. However,
costs have increased as many new technologies are expensive. This study was carried out to investigate the clinical outcomes
and fusion rates of a low implant load construct of unilateral pedicle screws and a translaminar screw in transforaminal lumbar
interbody fusion (TLIF) which reduced the cost of the posterior implants by almost 50%. Nineteen consecutive patients who
underwent single level TLIF with this construct were included in the study. Sixteen patients had a TLIF allograft interbody
spacer placed, while in three a polyetheretherketone (PEEK) cage was used. Follow-up ranged from 15 to 54 months with a mean
of 32 months. A clinical and radiographic evaluation was carried out preoperatively and at multiple time points following
surgery. An overall improvement in Oswestry scores and visual analogue scales for leg and back pain (VAS) was observed. Three
patients underwent revision surgery due to recurrence of back pain. All patients showed radiographic evidence of fusion from
9 to 26 months (mean 19) following surgery. This study suggests that unilateral pedicle screws and a contralateral translaminar
screw are a cheaper and viable option for single level lumbar fusion. 相似文献
65.
Bal Krishna Ojha Mazhar Husain Manu Rastogi Anil Chandra Ashish Chugh Nuzahat Husain 《Acta neurochirurgica》2009,151(7):843-847
Objective This is the first report of the simultaneous combined use of trans-sphenoidal and trans-ventricular-endoscopic route for decompression
of a giant pituitary adenoma.
Method A 38 year old man presented to us with symptoms of raised intracranial pressure along with visual and hypothalamic disturbances.
The CT scan revealed destruction of the sella by a large (5 × 3.5 × 2.5 cm) well defined enhancing mass in the sella and suprasellar
region extending laterally up to the cavernous sinuses and both carotid arteries and superiorly into the lumen of the 3rd
ventricle producing obstructive hydrocephalus. On T2WI of the non-contrast MRI scan the mass was iso-intense to grey matter
suggesting the possibility of a firm nature of the adenoma. The tumour was first approached by the standard trans-sphenoidal
route and as predicted from the pre-operative MRI, the tumour was found to be firm and not amenable to suction. After decompression
of the intra-sellar part of the tumour, the intracranial pressure was raised in an attempt to make the remainder of the tumour
descend into the sella but without success. The suprasellar part of the tumour was then simultaneously addressed via a trans-ventricular-endoscopic
route but the firm tumour did not yield to endoscopic instruments viz. biopsy forceps, angiographic catheter and electrosurgical
probes. It was then gently pushed down towards the sella and decompressed piecemeal by using trans-sphenoidal instruments.
The sellar cavity was reconstructed using fat, fascia lata graft and a piece of septal bone.
Results Post-operatively, the patient showed a remarkable improvement of his symptoms of raised intracranial pressure, hypothalamic
dysfunction and visual disturbances. Follow-up imaging at 2 months and 1 year, did not show any residual or recurrent tumour.
Conclusions This novel technique of the combined trans-sphenoidal and simultaneous trans-ventricular-endoscopic approach is a viable option
for patients with giant fibrous pituitary adenoma when the tumour is not yielding to the trans-sphenoidal route alone. 相似文献
66.
OBJECTIVE: To describe a case of left vagal nerve stimulation (VNS) resulting in immediate cessation of status epilepticus (SE) with good neurological outcome. CASE DESCRIPTION: A 30-year-old man with medically intractable seizures including episodes of SE was successfully treated using left VNS. After requiring discontinuation of phenytoin, valproic acid, carbamazepine, and topiramate because of severe allergic reactions resembling Stevens-Johnson syndrome, the patient required pentobarbital coma along with phenobarbital, tiagabine, and levetiracetam for seizure frequency reduction. He underwent left vagal nerve stimulator placement after nearly 9 days of barbiturate-induced coma, with stimulation initiated in the operating room. On the following day, electroencephalography revealed resolution of previously observed periodic lateral epileptiform discharges and the patient was free of seizures. Prestimulation seizure frequency was recorded at 59 times a day, with some seizures enduring 45 minutes despite barbiturate coma. Poststimulation, the patient has been free of seizures for 19 days and is presently taking only levetiracetam and phenobarbital, from which he continues to be successfully weaned without seizures. He is awake, alert, and can recall events leading up to his seizures, with good long-term memory and residual left upper extremity and lower extremity weakness. CONCLUSION: This case illustrates the role of left vagal stimulation in the treatment of SE and otherwise medically intractable seizures caused by allergic reactions. To our knowledge, this is the first case in the world literature for adults reporting cessation of SE after VNS. Another case with a similar improvement has been reported in the pediatric population. 相似文献
67.
The incidence of traumatic hip dislocation has increased in recent years as a result of high-energy trauma. Anterior hip dislocation forms less than 10-15% of all traumatic hip dislocations. Only a few case reports describe anterior dislocation along with acetabular fractures. The acetabular fracture involved the anterior wall or column in all such cases. We describe a rare case in which anterior superior dislocation of the hip was associated with a large fracture fragment of theposterior acetabular rim and adjacent wall. 相似文献
68.
BACKGROUND: The published results of carotid endarterectomy (CEA) in chronic renal insufficiency (CRI) patients are contradictory, mostly because of the relatively small number of patients in these studies. To better assess the neurologic complications and mortality, we reviewed a recent and substantially larger series of CRI patients who underwent CEAs. METHODS: From March 2000 to March 2003, 675 consecutive primary CEAs were performed in 609 patients (346 men, 57%) under general anesthesia. Asymptomatic carotid artery stenosis accounted for 71% of cases. CRI (serum creatinine level > or = 1.5 mg/dL) was detected in 166 patients (27%) who underwent 184 CEAs. The remaining 443 patients (73%) had 491 CEAs. RESULTS: Patients with CRI were different in age (76 +/- 8 years vs 72 +/- 9 years, P < .001), male gender (73% vs 51%, P < .001), coronary artery disease (50% vs 28%, P < .001), and diabetes mellitus incidence (38% vs 27%, P < .02). No significant difference in stroke rates was observed between the CRI patients and the control group (1.2% vs 0.5%). The mortality rate for CRI patients was 3%, whereas it was 0% for the control group ( P < .002). The 143 CRI patients with serum creatinine levels from 1.5 to 2.9 mg/dL had a 0.7% mortality rate, whereas it was 17% for 23 patients with serum creatinine levels of 3 mg/dL or more ( P < .001). The stroke rate for the former group was 0.7% and 4.3% for the latter group (NS). Asymptomatic (16) and symptomatic (7) patients with serum creatinine levels of 3 mg/dL or more had mortality rates of 13% and 28%, respectively, with P = .6. CONCLUSION: The high mortality rate observed in patients with serum creatinine levels of 3 mg/dL or more after CEA calls for a nonoperative approach in the management of asymptomatic patients. 相似文献
69.
OBJECTIVE: To present our experience with buccal mucosa urethroplasty for substitution of all segments of the anterior urethra, as the buccal mucosal graft (BMG) has emerged as the tissue of choice for single-stage reconstruction of bulbar urethral strictures, but its use for reconstructing meatal, pendulous and pan-urethral strictures has not been widely reported. PATIENTS AND METHODS: Between January 1998 and October 2003, 92 patients had a BMG substitution urethroplasty at our institution; 75 had a single-stage dorsal onlay BMG urethroplasty (bulbar 41, pendulous 16 and pan-urethral 18; six combined penile skin flap and BMG) and 17 (pendulous five, pan-urethral 10, bulbar two) a two-stage urethroplasty. Recurrence rates, complications and cosmetic outcomes were analysed retrospectively. RESULTS: Over a median (range) follow-up of 34 (8-72) months, 66 (88%) patients with a one-stage reconstruction (14/16 pendulous; 37/41, 90%, bulbar; 15/16 pan-urethral) remained stricture-free. The mean (range) time to recurrence was 9.4 (3-17) months. Of the nine recurrent strictures, six were managed by one-stage optical urethrotomy and three required a repeat urethroplasty. In patients who had a staged procedure, after a mean follow-up of 24.2 (9-56) months, one had complete graft loss, requiring re-grafting, five required stomal revision after stage 1, and only two (12%) developed a recurrent stricture after the two-stage urethroplasty. CONCLUSION: A one-stage dorsal onlay BMG urethroplasty provides excellent results for strictures involving any segment of the anterior urethra. The BMG appears to be the most versatile urethral substitute, as it can be successfully used for both one- and two-stage reconstruction of the entire anterior urethra. 相似文献
70.
PURPOSE: We evaluated the effectiveness of terminal loop cutaneous ureterostomy as a means of urinary drainage in kidney transplant recipients during a 20-year period. MATERIALS AND METHODS: Five cadaveric and 2 living related patients underwent kidney transplantation with terminal loop cutaneous ureterostomy between 1984 and 2004. These patients had no usable bladder or they were not suitable candidates for intermittent catheterization. RESULTS: Followup was 20 months to 17 years. One patient underwent stomal revision 5 months after renal transplantation. Current serum creatinine 4 years later was 166 mumol/l. The remaining 6 patients had no evidence of ureteral obstruction and rarely had bacteriuria or urinary tract infections. Four patients had a functioning allograft with normal serum creatinine. One patient died with a normally functioning allograft and the remaining patient lost his graft due to chronic rejection. No patient in this series lost the graft due to a urological cause. Overall outcomes included excellent allograft function with minimal infection or stomal stenotic complications. CONCLUSIONS: Terminal loop cutaneous ureterostomy is a simple, safe and alternative means of urinary diversion in patients with renal transplant and a defunctionalized lower urinary tract. 相似文献