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PURPOSE: The high-powered holmium:YAG laser can be used for incision, ablation and resection of the prostate. The technique of holmium laser resection of the prostate is compared to transurethral prostatic resection for surgical management of benign prostatic hyperplasia in this prospective randomized study. MATERIALS AND METHODS: A total of 120 urodynamically obstructed cases were randomized to holmium laser or transurethral prostatic resection. All eligible patients were assessed preoperatively and at 3 weeks, and 3, 6 and 12 months postoperatively with an American Urological Association symptom score, peak urinary flow rate, and questionnaires concerning sexual function and continence. Preoperative pressure flow study, ultrasound prostate volume assessment and post-void residual volume measurement were repeated at the 6-month visit. All complications were noted. RESULTS: Holmium laser and transurethral resections resulted in significant improvements in symptom score, quality of life score, peak urinary flow rate and post-void residual urine measurements. Operating time was significantly longer in the holmium group but nursing contact time, catheter time and hospital stay were significantly less compared to the transurethral prostatic resection group. Urodynamic results were equivalent at 6 months. There were fewer side effects in the holmium group. Effects on continence, potency and symptoms were similar with 1-year followup. CONCLUSIONS: Holmium and transurethral resections of the prostate appear to be equivalent in surgical management of bladder outflow obstruction due to benign prostate hyperplasia. Perioperative morbidity was less in the holmium group.  相似文献   
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Background : Total thyroidectomy is widely practised in Australasia for papillary and follicular thyroid carcinoma. Data from large overseas series have demonstrated that patients with these cancers may be separated into risk groups based on clinicopathological prognostic factors. Furthermore, evidence suggests that low-risk patients may be safely treated with less than total thyroidectomy. The aim of the present paper was to determine what proportion of our patients with papillary and follicular thyroid cancer were in the low-risk group in order to select candidates for less aggressive treatment. Methods : A prospectively documented series of 175 previously untreated patients with papillary and follicular thyroid carcinoma, treated principally by total thyroidectomy over a 10-year period, was divided into risk groups using the Mayo Clinic, Lahey Clinic and Memorial Hospital prognostic scoring systems. Complication rates for 103 patients treated by total thyroidectomy were also studied and reported. Results : Women outnumbered men by 2.3:1. There were 128 papillary carcinomas (73%) and 47 follicular cancers (27%). These tumours were < 4 cm in diameter in 81% of patients, and 41% of patients were 40 years of age or younger. Low-risk patients accounted for 75, 81 and 45% of the study group, respectively, when the three prognostic scoring systems were applied to our patient population. The rates for recurrent laryngeal nerve palsy and permanent hypoparathyroidism for patients having total thyroidectomy were 1 and 1.9%, respectively. In the low-risk group there were no permanent complications. Conclusion : Most patients treated at Royal Prince Alfred Hospital during the past 10 years were low-risk patients who may have been eligible for less aggressive surgical treatment.  相似文献   
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Purpose

We assessed the location of urethral arteries in patients with urethral stricture using color Doppler ultrasound.

Materials and Methods

We performed 41 color ultrasound studies of the urethra in 33 patients 17 to 76 years old. The linear array transducer was placed on the ventral surface of the penis and perineum to image the urethra and periurethral structures. In addition of evaluating the extent of stricture disease, color Doppler ultrasound determined the location of the urethral arteries at the segment with stricture.

Results

The number and site of the urethral arteries vary among individuals. Contrary to the common belief that these arteries are located at the 3 and 9 o'clock positions, we have found that in the bulbous urethra the arteries are at the 1 to 2 o'clock positions in 14% of cases, 3 to 4 in 22%, 5 to 6 in 17%, 7 to 8 in 18%, 9 to 10 in 18% and 11 to 12 in 11%. The arteries may be close to the surface of the urethral lumen, especially in patients who have undergone previous urethral procedures. Preoperative evaluation of urethral artery location may be helpful for preventing arterial bleeding at visual internal urethrotomy.

Conclusions

Color Doppler ultrasound can effectively assess the extent of stricture disease and urethral artery sites. Because the location of the urethral arteries varies among patients, individual preoperative assessment is advisable. Color Doppler ultrasound is currently our imaging method of choice for evaluating strictures of the pendulous and bulbous urethra.  相似文献   
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The ideal preoxygenation period prior to laryngoscopy in children is unclear. This study was performed to determine an appropriate duration of preoxygenation for infants and children prior to laryngoscopy using endtidal oxygen (Fe ′O2) criteria. Healthy paediatric patients for elective day surgery procedures were studied. An inflatable mask connected to an oxygen-primed paediatric anaesthesia semiclosed circuit was placed on the face while patients breathed spontaneously during 6.min?1 oxygen flow. An Fe ′O2 of 0.9 was considered the endpoint, and if not achieved in two min the protocol was ended. Fifty-eight children were studied. Six patients never achieved an Fe ′O2 of 0.9 and were not considered in the analysis. The times (in seconds with mean±sd and range) to achieve a minimum endtidal (Fe ′O2) of 0.9 for under six months were 36±11.4(20–50), 7–12 months were 35.5±13.3(20–60),13–36 months were 42.6±18.7(20–90), 37–60 months were 50.8±18.5(30–90), >60 months were 68.4±24.1(30–100). Logistic regression curves were determined for each age group describing the probability of achieving an Fe ′O2 of 0.9 against time of preoxygenation. All children with satisfactory mask fit were able to preoxygenate to an Fe ′O2 of 0.9 within 100 s.  相似文献   
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Introduction: Total intravenous anesthesia with propofol and a synthetic opioid is a frequently chosen anesthetic technique for posterior spinal fusion. Despite its utility, adverse effects may occur with high or prolonged propofol dosing regimens including delayed awakening. The current study investigated the propofol‐sparing effects of the concomitant administration of the α2‐adrenergic agonist, dexmedetomidine, during spinal fusion surgery in adolescents. Methods: The surgical database of the department of orthopedic surgery was searched and patients (12–21 years of age) were identified who had undergone spinal fusion for either idiopathic or neuromuscular scoliosis during the past 24 months. Patients were assigned to two groups. Group 1 included patients anesthetized with propofol and remifentanil and group 2 included patients anesthetized with dexmedetomidine, propofol, and remifentanil. In the latter group, dexmedetomidine was administered as a continuous infusion of 0.5 μg·kg?1·h?1 started after the induction of anesthesia without a loading dose. Propofol was adjusted to maintain the bispectral index (BIS) number at 40–50 and remifentanil was adjusted to maintain the mean arterial pressure (MAP) at 50–65 mmHg. Labetolol or hydralazine was used if the MAP could not be maintained at 50–65 mmHg with remifentanil up to a maximum dose of 0.6 μg/kg/min. Statistical analysis included a nonpaired t‐test for parametric data (age, weight, remifentanil/propofol infusion requirements, and heart rate/blood pressure values). A nonparametric statistical analysis (Dunn) was used to compare BIS numbers. Parametric data are presented as the mean ± sd while nonparametric data are presented as the median and the 95th percentile confidence intervals. Results: Twelve patients received propofol–remifentanil–dexmedetomidine and 24 received propofol–remifentanil. There were no differences in the demographic data, BIS numbers or hemodynamic parameters between the two groups. There was a reduction in the propofol infusion requirements in patients who also received dexmedetomidine (71 ± 11 μg·kg?1·min?1) compared with those receiving only propofol–remifentanil (101 ± 33 μg·kg?1·min?1, P = 0.0045). No difference was noted in the remifentanil infusion requirements or the use of supplemental agents (hydralazine and labetolol) to maintain controlled hypotension. Conclusion: The concomitant use of dexmedetomidine in patients undergoing spinal fusion reduces propofol infusion requirements when compared with those patients receiving only propofol and remifentanil.  相似文献   
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