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991.
Different patterns of technetium-99m sestamibi uptake in multiple myeloma   总被引:2,自引:0,他引:2  
Technetium-99m 2-methoxyisobutylisonitrile (99mTc-MIBI) has been proposed as a potential tracer in patients with multiple myeloma (MM). The aims of this study were to evaluate the incidence of various patterns of diffuse 99mTc-MIBI uptake in patients with MM, to assess their relationship with clinical status and stage of disease, and to try to clarify the meaning of the diffuse bone marrow uptake of 99mTc-MIBI. Thirty-nine consecutive patients with MM were studied. Twenty-nine of these patients had active disease (13 in stage I, ten in stage II, and six in stage III) and ten were in remission after chemotherapy. Anterior and posterior whole-body scans were obtained 10 min after i.v. injection of 555 MBq of 99mTc-MIBI. The scans were classified as showing: pattern N, when only physiological uptake was present; pattern D, when diffuse bone marrow uptake was observed; pattern F, when areas of focal uptake of the radiotracer were evident; or pattern D+F, when both D and F patterns were observed. Diffuse bone marrow uptake was scored according to extension and intensity. Seven of the 39 patients (18%) showed pattern N, 18 (46%) pattern D, 2 (5%) pattern F, and 12 (31%) pattern D+F. Of the 32 patients with a positive 99mTc-MIBI scan (i.e. showing pattern D, F or D+F), 29 (91%) had active disease. Only three patients in remission showed pattern D, but with a very low bone marrow uptake score. Both extension and intensity of diffuse bone marrow uptake correlated with the amount of the monoclonal component and the percentage of bone marrow plasma cells. The distribution of the 99mTc-MIBI uptake patterns differed among patients in different stages of disease. Using as criteria for advanced stage the presence of either focal uptake (pattern F or D+F) or pattern D with a high score, high (90%) diagnostic accuracy was obtained. In conclusion, the patterns of 99mTc-MIBI uptake in patients with MM are related to both the clinical status and the stage of disease. The presence of focal uptake or of intense diffuse bone marrow uptake suggests that the patient has active and advanced stage disease, while a negative scan in a patient with MM clearly indicates remission. Received 12 February and in revised form 16 April 1998  相似文献   
992.
PurposeTo investigate an examiner-independent catheter venography protocol that could be used to reliably diagnose venous outflow abnormalities in patients with multiple sclerosis (MS) and chronic cerebrospinal venous insufficiency and to determine whether venous angioplasty is effective in the treatment of these abnormalities.Materials and MethodsA total of 313 patients with MS and 12 patients with end-stage renal disease underwent echo-color Doppler sonography and catheter venography of the internal jugular veins (IJVs) to evaluate contrast medium clearance time. In patients with venous outflow anomalies, balloon angioplasty of the IJVs was performed.ResultsA contrast medium clearance time cutoff value of 4 seconds or less provided the maximal combination of sensitivity and specificity for the right IJV (sensitivity, 73.4%; specificity, 100%) and left IJV (sensitivity, 91.4%; specificity, 100%). IJVs with a clearance time between 4.1 and 6 seconds had moderate delayed flow (MDF), and IJVs with a clearance time longer than 6 seconds had severe delayed flow (SDF); 89% of patients showed MDF/SDF through at least one IJV, 79% showed MDF/SDF through both IJVs, and only 5% showed normal flow in both IJVs. Balloon angioplasty was immediately able to improve flow in at least one IJV in 69% of patients, but venous flow was normalized in both veins in only 37% of patients; SDF persisted after angioplasty in 32% of patients.ConclusionsThere is a high prevalence of abnormal delayed flow through IJVs in patients with MS. Venous angioplasty was effective in only a minority of patients with SDF.  相似文献   
993.
ObjectivesThe purpose of this observational study was to examine differences in preschoolers’ sedentary time and physical activity (PA) participation between preschool-attending weekdays with and without a teacher-led structured PA session.DesignA sample of 200 preschoolers (5.3 ± 0.4 y; 113 boys) from 26 preschools in Flanders, Belgium were included in data analysis.MethodsParticipants wore a GT1M ActiGraph accelerometer on one preschool-attending weekday with and on one preschool-attending weekday without the provision of a teacher-led structured PA session. Preschoolers’ sedentary time, light PA, and moderate-to-vigorous physical activity (MVPA) during the time in preschool (08:00–16:00 h) and after preschool (16:00–20:00 h) were estimated. To assess differences in the outcome measures between both days, multi-level linear regression models were conducted.ResultsDuring the time at preschool, lower sedentary levels (β = 13.0 min; SE = 1.6; p < 0.001) and higher light PA (β = 2.9 min; SE = 0.7 p < 0.001) and MVPA levels (β = 10.1 min; SE = 1.1; p < 0.001) were prevalent on days with a structured PA session compared to days without a structured PA session in both boys and girls. After preschool, no differences were found between both days in sedentary time (β = 0.7; SE = 1.4; p > 0.05), light PA (β = 0.3; SE = 0.5; p > 0.05), and MVPA (β = 0.3; SE = 0.9; p > 0.05).ConclusionsThe results demonstrate that no compensatory changes were found after preschool for the structured PA session during the preschool hours. Therefore, a teacher-led structured PA session integrated in the preschool curriculum is a promising mean to decrease sedentary time and to increase PA in preschool-aged boys and girls.  相似文献   
994.
OBJECTIVES: To evaluate the dose-response relationship and safety/tolerability of solifenacin succinate (YM905) in the treatment of overactive bladder (OAB), and to compare its efficacy and safety/tolerability with tolterodine 2 mg twice daily. PATIENTS AND METHODS: This multicentre study included a 2-week single-blind placebo run-in, a 4-week double-blind placebo-controlled active treatment phase, and a 2-week follow-up. Men and women with an OAB and urodynamic evidence of detrusor overactivity were randomized to placebo or solifenacin 2.5, 5, 10 or 20 mg once daily, or tolterodine 2 mg twice daily. RESULTS: Of 265 patients enrolled, 225 were randomized and 192 completed the study. Solifenacin 5, 10 and 20 mg produced statistically significant (P < 0.05) improvements in voids/24 h vs placebo, whereas tolterodine did not; the mean change with tolterodine was between those with solifenacin 2.5 and 5 mg. The outcome was similar for the mean change from baseline to endpoint in mean volume voided/void. For incontinence and urgency episodes/24 h the solifenacin dose groups showed numerically superior changes vs placebo; the mean effects with tolterodine were generally smaller than with solifenacin. Most of the efficacy effect of solifenacin was evident at 2 weeks. Quality-of-life outcomes supported the efficacy results. Solifenacin 5 and 10 mg were well tolerated; there were no serious treatment-related adverse events. The incidence of dry mouth was 14% for solifenacin 5 and 10 mg, 2.6% for placebo and 24% for tolterodine. CONCLUSION: In this study, the 5- and 10-mg doses of solifenacin appeared to be the most clinically effective for treating OAB, considering the balance between efficacy, quality of life and tolerability. From the results of this study solifenacin 5 and 10 mg were selected for further evaluation in large-scale phase 3 studies.  相似文献   
995.
Background: Laparoscopic adjustable gastric banding (LAGB) has usually been performed as an inpatient procedure with an average hospital stay of 2-4 days. The aim of this study was to assess the feasibility of LAGB as an ambulatory procedure in selected patients. Methods: Potential candidates for ambulatory LAGB were recruited from patients consulting for obesity surgery. The main inclusion criteria were BMI >35 kg/m2 with co-morbid conditions, living within a reasonable distance from the hospital, and adult company at home. The patients were admitted at 0700 hours on the day of surgery, underwent laparoscopic placement of a Lap-Band? system and were discharged home that evening. Results: 9 women and 1 man underwent outpatient LAGB. Mean age was 36 (range 18-52) years and mean BMI was 38.4 kg/m2 (range 35.1-43.3). Co-morbidities included functional dyspnea (6), osteoarthritis (4), arterial hypertension (4), type 2 diabetes (2) and dyslipidemia (1). 7 patients had undergone previous abdominal surgery: cesarian section (4), appendectomy (3), cholecystectomy (1) and hysterectomy (1). All patients had an American Society of Anesthesiologists (ASA) classification of II. The average operating time was 87 minutes (range 65-115). The mean time lapse between the end of the operation and discharge from hospital was 9.6 hours. There were no readmissions, and no complications were noticed at 1 month postoperatively. The patients' satisfaction with the ambulatory LAGB procedure was high. Conclusion: The present study demonstrates that LAGB for obesity may be performed on an ambulatory basis without complications.  相似文献   
996.
Background: Revision of failed gastric restrictive procedures to proximal Roux-en-Y gastric bypass (RYGBP) is the standard for many bariatric surgeons. Where the patient is not a suitable candidate or simply refuses gastric bypass, an alternative is herewith proposed. Methods: 3 patients had undergone a gastric banding as the original operation and 1 patient had had a vertical banded gastroplasty (VBG). 1 patient presented with insufficient weight loss, 1 with regain of weight and 2 with complaints of food intolerance and vomiting. The gastric bands were removed by hand-assisted laparoscopy (HALS), with conversion to a VBG. In the patient with stomal stenosis after a VBG, HALS interposition of PTFE was performed to enlarge the collar. Results: In 2 patients, further weight reduction was achieved. In the other 2 patients, relief of symptoms was achieved.There were no complications during or after the revisional surgery. Conclusion: HALS conversion of a gastric banding to a VBG, or PTFE interposition in the case of stomal stenosis after a VBG, can be a valuable alternative for patients unsuitable for or refusing proximal RYGBP.  相似文献   
997.

Background

Intestinal anastomosis is a complex procedure during laparoscopy, mainly due to the difficulties knotting the sutures. Unidirectional barbed sutures have been proposed to simplify wall and mesentery closure, but the results for intestinal anastomosis are not clear. This study aimed to establish the feasibility and the safety of laparoscopic intestinal anastomosis using barbed suture.

Methods

Between June 2011 and May 2012, 15-cm-long unidirectional absorbable barbed sutures (V-Loc; Covidien, Mansfield, MA, USA) were used for all laparoscopic intestinal anastomoses: one suture for closure of intestinal openings after mechanical anastomoses and two sutures for hand-sewn anastomoses.

Results

Over a 1-year period, 201 consecutive patients required 220 laparoscopic anastomoses for gastrojejunostomy (n = 177; 172 during Roux-en-Y gastric bypass and 5 after gastrectomy), ileocolostomy (n = 15), colocolostomy (n = 1), esophagojejunostomy (n = 5), and jejunojejunostomy (n = 22; 4 after small bowel resection and 18 during gastric bypass or gastrectomy). Senior and training surgeons performed 209 closures of intestinal openings and 11 hand-sewn anastomoses. There was no conversion to usual sutures. One fistula occurred in an esophagojejunostomy and was managed conservatively. One self-limited anastomotic bleeding occurred, and no anastomotic stenosis occurred during 6 months of follow-up evaluation.

Conclusions

The use of knotless barbed suture for laparoscopic intestinal anastomosis is safe and reproducible.  相似文献   
998.
PURPOSE: To evaluate whether the time-intensity curve can improve characterisation of solitary thyroid nodules. MATERIAL AND METHODS: From June to December 2000 we studied 61 patients (16 men and 45 women, mean age 46 years) with solitary thyroid nodules that were not associated with any important hormonal alteration and that showed poor tracer uptake at scintigraphy. We evaluated the Power Doppler vascular pattern before and after a 60" intravenous injection of 2.5 g of Levovist (diluted in 7 ml). The study lasted 5 minutes from the beginning of the infusion. Finally, the time-intensity curves were processed. All the nodules underwent fine needle aspiration biopsy (FNAB) and excision biopsy. RESULTS: Histology revealed 43 benign lesions and 18 malignant lesions. At contrast-enhanced Power Doppler 83.4% (15/18) of the malignant nodules were found to be hypervascularized, while 16.6% (3/18) were hypovascularized. Of the benign lesions, 90.7% (39/43) were hypervascularized, 9.3% (4/43) were hypovascularized. All the nodules, both hyper- and hypovascularized, displayed rapid and intense wash-in curves. By contrast, the wash-out curves were regular and monophasic in 40/43 (93%) benign lesions (36 hypervascularized and 4 hypovascularized lesions) and irregular and polyphasic in 16/18 (89%) malignant lesions (13 hypervascularized and 3 hypovascularized lesions); 3/43 (7%) benign nodules showed polyphasic wash-out and 2/18 malignant lesions (11%) showed monophasic wash-out. DISCUSSION AND CONCLUSIONS: Time-intensity curves, and particularly wash-out curves, provide useful information for the characterisation of solitary thyroid nodules. 93% of benign nodules (with regular vascularization) showed a monophasic pattern of the wash-out curve, while 89% of malignant nodules ("anarchical" vascularization) had polyphasic wash-out curves. This behaviour was observed in both hypervascularized and hypovascularized lesions. Our method proved to have a sensitivity of 88% and a specificity of 93%. The study of time-intensity curves could therefore enable us to differentiate between benign and malignant lesions and characterise hypovascularized malignant nodules which would not be observed without contrast agent.  相似文献   
999.
Sertoli细胞诱导大鼠肝内胰岛移植物免疫豁免的实验研究   总被引:2,自引:3,他引:2  
目的 探究睾丸Sertoli细胞能否对肝内共移植的胰岛移植物提供免疫豁免作用以及共移植的睾丸Sertoli细胞最佳数量。方法将同种大鼠胰岛及不同数量的睾丸Sertoli细胞同时移植于糖尿病受体的肝内,观察移植物存活情况、胰岛功能、并检测移植物内胰岛素和Fas配体(FasL)表达以及浸润淋巴细胞凋亡情况。结果单纯胰岛移植组平均存活期为(5.6±0.8)d,同时与胰岛细胞在肝内共移植的睾丸细胞数增加至1×107个时,平均存活期为(41.4±4.61)d,明显延长(P<0.05),胰岛移植物中有大量表达FasL的睾丸细胞和表达胰岛素的胰岛细胞.在移植物周围有大量浸润的淋巴细胞凋亡。结论睾丸Sertoli细胞与胰岛细胞同时在肝内共移植,通过诱导局部豁免而延长胰岛移植物的存活时间,且同时共移植1×107个Sertoli细胞时效果最好。  相似文献   
1000.
目的探讨直肠癌患者根治性前切除术后复发转移的相关临床病理因素。方法应用单因素和多因素分析方法,回顾性分析1990年至1999年262例直肠癌根治性前切除术患者的临床病理因素。结果单因素分析显示,Dukes分期、淋巴结转移、肿瘤部位、分化程度、远切缘长度与直肠癌前切除术后复发转移有关,肿瘤部位、远切缘长度与局部复发有关。多因素分析显示,分化程度和远切缘长度是影响术后复发转移的预后因素,远切缘长度是影响术后局部复发的预后因素。结论肿瘤分化程度和远切缘长度是影响直肠癌患者根治性前切除术后复发转移的重要预后因素,肿瘤远切缘短的患者术后局部复发的风险增大。  相似文献   
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