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951.
1993年7月~1998年1月为103例(106只眼)难治性青光眼患者施行国产房水引流物(HAD)置入术。术后平均随访328月。术后1年时平均眼压22±1.4kPa。术后1~5年的手术成功率分别为838%,804%,771%,710%及643%。术中联合应用丝裂霉素C的病例,其术后1年时的成功率为895%。术后常见的并发症有持续性浅前房,局限性脉络膜脱离及眼压升高等。认为HAD可用于治疗难治性青光眼。  相似文献   
952.
BACKGROUND: The pharmacokinetics of the steroid anesthetic eltanolone have been studied in male volunteers. However, steroids may exhibit gender-related differences in pharmacokinetics and surgery may alter drug disposition. METHODS: Male (n = 12) and female (n = 9) ASA 1-2 patients (age 26-45 yrs) undergoing discectomy with microsurgical technique were included. Anesthesia was induced with eltanolone 0.75 mg/kg and maintained with nitrous oxide, fentanyl and atracurium. Venous blood was sampled for up to 12 h and analyzed for eltanolone and its major metabolites. RESULTS: Induction was smooth and anesthesia uneventful, except that five cases developed a mild transient erythema. Loss of verbal contact occurred within 20-60 s. Pharmacokinetics in one person deviated significantly from the rest of the subjects. No difference between groups with respect to the primary outcome variable noncompartmental clearance (Cl, 1/min) 1.7 vs 1.6, was found. However, the volume of distribution at steady state (Vss, 1/kg) was larger in women (3.1) compared to men (1.3). The pharmacokinetics followed a three-compartment model. The half-lives (min) of the alpha, beta and gamma phases (men vs women, medians) were 1.5 vs 2.2, 42 vs 40 and 222 vs 360, respectively. Area under the curve (AUC, min microgram/l) was 39,810 vs 34,905. Context-sensitive modelling indicated that it may take 10 min more for women than men to recover from an eltanolone infusion of 2 h duration. CONCLUSION: The gender-related differences in the pharmacokinetics of eltanolone were small, and of little clinical significance for induction of anesthesia with eltanolone.  相似文献   
953.
BACKGROUND: Proteolytic enzymes and oxygen free radicals released from activated leucocytes contribute significantly to the organ dysfunction associated with cardiopulmonary bypass. Leucocyte depletion during extracorporeal circulation should reduce the release of these toxic compounds and thereby improve postbypass myocardial and pulmonary function. Recently, a leucocyte-specific arterial line filter to achieve leucocyte depletion during clinical perfusion has become commercially available. The aim of this study, therefore, was to evaluate the influence of the leucocyte depleting arterial line filter on proteolytic enzyme release, oxygen free radical release and postbypass pulmonary and myocardial function in patients undergoing bypass surgery. METHODS: Forty patients undergoing elective aortocoronary bypass surgery were included into this prospective, randomized clinical study, 20 in the leucocyte depletion (LG-6 group, leucocyte-specific arterial line filter) and 20 in the control group (AV-6 group, standard arterial line filter). White cell count, differential white cell count, plasma elastase concentration, plasma malondialdehyde concentration and C-reactive protein were determined before, twice during and immediately after cardiopulmonary bypass, at the end of surgery and 6 and 20 h thereafter. RESULTS: White cell count, differential white cell count, malondialdehyde and C-reactive protein were not significantly different between LG-6 and control patients. Plasma elastase concentrations were significantly (P < or = 0.03) higher during and immediately after extracorporeal circulation in LG-6 group patients. Need for inotropic support, arterial pO2 after extracorporeal circulation and perioperative CK MB mass and troponin I release were not different between the two groups of patients. CONCLUSION: The use of a leucocyte depleting arterial line filter is associated with an increased release of the proteolytic enzyme elastase, but does not reliably and consistently achieve effective leucocyte depletion during clinical perfusion. In contrast to previous studies, we could not demonstrate any significant difference in postbypass pulmonary or myocardial function between patients perfused with the leucocyte-specific arterial line filter and control patients. Our data do not support the routine use of a leucocyte depleting arterial line filter during clinical perfusion in patients undergoing elective aortocoronary bypass surgery.  相似文献   
954.
Summary  The authors report a series of 13 patients with osteoporotic vertebral fractures treated by transpedicular vertebroplasty. Because of a neurological complication due to posterior leakage of acrylic cement the classical percutaneous approach was converted to an open surgical procedure. The latter allows direct visual control of neural structures and immediate removal of spilled cement, thus eliminating the danger of compressive, chemical and thermal effects of methyl methacrylate on neural elements.  By use of this elegant technique primary stability of fractured vertebras is obtained leading to prompt pain relief in all patients. Surgically controlled vertebroplasty can be used in conjunction with internal fixation. By having studied the different ways of cement escape in their patients, the authors are convinced that surgically controlled vertebroplasty is safer than percutaneous vertebroplasty.  相似文献   
955.
 The data of 48 studies (published between 1903 and 1996), presenting information of all together 107 patients (108 lesions) regarding pre-treatment clinical and radiological factors, treatment strategies, and the outcome, plus our own experience of nine patients were retrospectively re-analyzed. The prognostic influence of pre-treatment factors was estimated with the chi-square statistics. Clinical evaluation before/after treatment was performed using the Frankel scale. The average bleeding rate was obtained from the ratio of percentage of first bleeding events in the population to the mean age of the population.  There were 47 males and 69 females (aged from twelve to 88 years). Thirty nine percent of the lesions were found in the cervical, 54% in the thoracic (30% upper, 24% lower) and 7% in the lumbar cord. The peak age of presentation was in the fourth decade, the median duration of symptoms was 32 months. Clinical symptoms before treatment were progressive in all cases. Three patterns of clinical presentation could be identified: a) episodes of stepwise clinical deterioration (30%), b) slow progression of neurological decline (41%), c) acute onset with rapid or gradual decline over weeks or months (26%). 58% of the lesions showed clinical or radiological signs of haemorrhage. In 66% of surgical patients (91 efficiently documented cases), clinical improvement was achieved, 28% remained unchanged and 6% deteriorated. Whereas age, sex and lesion location had no influence on the results, duration of symptoms (<three years) correlated significantly to a better outcome (p<0.02).  Surgical management in symptomatic patients is recommended. Once clinical signs caused by the malformation have appeared, the patients tend to experience progressive neurological deterioration.  相似文献   
956.
957.
To assess the potential for atmospheric nitrogen to enter the nonventilated lung following the initiation of single-lung ventilation, the nonventilated lung of 10 patients undergoing video-assisted thoracoscopy was connected to the air in a water-filled spirometer, and gas movement out of and back into the lung was measured. Airway pressure from both lungs and pleural pressure from the nonventilated side were also measured. With each breath of positive-pressure ventilation to the ventilated lung prior to the thoracic cavity being opened to the atmosphere, the pressure transmitted to the opposite hemithorax generated a mean (range) tidal movement of gas in the nonventilated lung of 134 (65-265) ml. In addition, ongoing gas exchange resulted in a progressive influx of gas from the spirometer over the 110-120 s measurement period of a mean (range) volume of 155 (70-320) ml. This easily preventable influx of atmospheric nitrogen could, in theory, predispose to arterial desaturation and to delayed lung collapse after the parietal pleura is opened.  相似文献   
958.
RATIONALE AND OBJECTIVES: The purpose of the study was to evaluate a method of producing obstruction of the common bile duct and concomitant biliary duct dilatation in an animal model. MATERIALS AND METHODS: Laparoscopic placement of a double-balloon occlusion device was used to produce common bile duct obstruction and bile duct dilatation in pigs. RESULTS: One week after the procedure, common bile duct obstruction and dilatation of the biliary tree were demonstrated with either percutaneous transhepatic cholangiography or percutaneous cholecystography. CONCLUSION: The use of this method is technically feasible and provides a useful subacute and chronic animal model of common bile duct obstruction and dilatation of the biliary tree for percutaneous interventional training and research purposes.  相似文献   
959.
Safe creation of pneumoperitoneum using an optical trocar   总被引:3,自引:3,他引:0  
The blind insertion of the Veress needle and the first trocar may cause serious complications. Therefore, many surgeons perform a minilaparotomy to safely position the first trocar. However, especially in obese patients, the dissection may be difficult and time consuming. As an alternative, optical trocars can be safely positioned under direct visualization. We report on our experience with the Optiview trocar in 200 patients and describe our preferred insertion technique. In our opinion, optical trocars are safe and easy to handle, offering several advantages over the use of the Veress needle and the minilaparotomy. Received: 19 February 1998/Accepted: 28 May 1998  相似文献   
960.
An intraabdominal abscess developed from a retained fecalith following laparoscopic appendectomy. We discuss the prevention and management of retained fecaliths in light of the numerous reports of retained gallstones. Received: 24 January 1997/Accepted: 17 November 1997  相似文献   
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