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991.

Background  

The purpose of this study was to evaluate the pattern of disc herniation and to investigate the associated symptoms in cases of isthmic spondylolisthesis. It is well known that the pathogenesis of degenerative spondylolisthesis associates with disc degeneration, followed by facet laxity and ligamentum flavum hypertrophy, which result in severe spinal canal stenosis. But isthmic spondylolisthesis is known to have a different pathogenesis. In isthmic spondylolisthesis, pseudodisc bulging is easily identified, and canal stenosis is comparatively rare. Therefore, we propose that isthmic spondylolisthesis has a different pattern of disc herniation from degenerative spondylolisthesis. We studied the type, incidence of disc herniation and clinical symptoms related to isthmic spondylolisthesis.  相似文献   
992.
Background  Acute appendicitis (AA) in elderly patients (60 years of age and older) is a challenging problem associated with significant morbidity and mortality when perforation is present. We hypothesized that laparoscopic appendectomy (LA) would enable an earlier correct diagnosis and have advantages in elderly patients. Methods  We performed a retrospective review of patients who underwent laparoscopic appendectomy for suspected AA. Data of elderly patients were compared to data of younger patients (18 to <60 years of age). Results  Fifty-four LA were performed in elderly patients and 423 in younger patients. Patients over the age of 60 years had more co-morbidities and required more frequent use of anticoagulants. Preoperative imaging (ultrasound or computerized tomography) was significantly more frequent in elderly patients (36% versus 15%), and was associated with a higher rate of confirmation of acute appendicitis (78% versus 55%), which allowed a decrease in the rate of negative surgical explorations to 4.1% in elderly patients compared to 10.2% in younger patients. Complicated appendicitis and conversions were more frequent in the elderly patients. This resulted in prolonged operative time and longer hospital stay for this group. The overall complication rate was equivalent in the two groups, without differences in the occurrence either of infectious complications or of complications related to surgical site. There were no deaths following appendectomy in our series. Conclusions  Laparoscopic appendectomy is safe in the elderly population and is not associated with any increase in morbidity. The high incidence of complicated appendicitis in elderly patients affects operative time and length of hospital stay following laparoscopic appendectomy, and it can also lead to an increased rate of conversion to an open procedure. Use of preoperative abdominal computerized tomography scan is mandatory in elderly patients to provide an early diagnosis and to decrease unnecessary surgical exploration when acute appendicitis is suspected.  相似文献   
993.
Premature neonates are frequently administered indomethacin, ibuprofen and gentamicin during the period of active glomerulogenesis. These drugs are known to have nephrotoxic effects, but the morphological effect of these drugs is unknown. The purpose of this study was to determine whether administration of these drugs during the late stages of glomerulogenesis in the rat has an effect on glomerular endowment. Rat pups were given, intraperitoneally, indomethacin, ibuprofen or indomethacin and gentamicin for the first 5 days of their postnatal life. The pups were killed at 14 days of age at completion of glomerulogenesis. The total number of glomeruli in the left kidney was determined by the physical disector/fractionator stereological technique. There was no difference between treatment groups in total number of glomeruli per kidney (P = 0.45). There were significantly fewer glomeruli per gram of kidney in those rat pups that had received indomethacin or ibuprofen (P < 0.0001). The reduction in the number of glomeruli per gram of kidney may indicate augmented growth of nephron tubules and/or collecting ducts, and/or be a consequence of oedema secondary to drug exposure. Further study is required to determine whether reduced glomerular number is seen in older animals or following exposure to these drugs at different time-points in kidney development.  相似文献   
994.
The objective of this study was to explore the influence of ureteral stent on renal pelvic pressure by urodynamic study. 41 patients (with unilateral renal and/or ureteral calculi) after minimally invasive percutaneous nephrolithotomy (MPCNL) were placed a 4.7-Fr ureteral stent and 16-Fr nephrostomy tube. Renal pelvic pressure of these patients was measured by urodynamic study at the 5–7 days after MPCNL. Renal pelvic pressure (RPP), intraabdominal pressure (IAP), and vesical pressure (VP) during the filling and voiding phases were detected by urodynamic study with intravesical perfusion. At the baseline, intraabdominal pressure (IAP0) was 27.52 ± 7.03 cmH2O, renal pelvic pressure (RPP0) was 33.07 ± 7.04 cmH2O; at the maximum cystometric bladder capacity (MCBC) during the filling phase, vesical pressure (VPvol) was 41.61 ± 10.34 cmH2O, renal pelvic pressure (RPPvol) was 39.44 ± 7.33 cmH2O; at the maximum vesical pressure during the voiding phase, vesical pressure (VPmax) was 74.95 ± 12.79 cmH2O, renal pelvic pressure (RPPmax) was 65.68 ± 17.03 cmH2O. (1) There was a strong relationship between RPP0 and IAP0 (P = 0.0001); (2) There was statistical significance among RPP0, RPPvol and RPPmax (P = 0.0001); (3) RPP was higher than 40 cmH2O during the voiding phase, and it was obviously relevant to the VP (P = 0.0001) but not to the MCBC (P = 0.2696). RPP increased mildly during the filling phase and dramatically during the voiding phase after stenting. RPP increased higher than the level required for a backflow (40 cmH2O) during the voiding phase. So it was encouraged to remove the stent at earlier stage or decrease using the ureteral stent if possible.  相似文献   
995.
Purpose  The overall incidence of postoperative alveolar air leakage (AAL) remains high; however, the mechanism regarding how to adequately heal such postoperative AAL remains to be elucidated. The aim of this study was to determine any correlations between the activity of the fibrinolytic and coagulation system in the postoperative pleural effusion and appearance or disappearance of postoperative AAL. Methods  This study prospectively investigated 25 patients who underwent a pulmonary lobectomy from July 2005 to March 2006. Pleural effusion was collected through the chest tube. Alpha 2 plasmin inhibitor-plasmin complex (PIC), as a fibrinolytic marker, and thrombin-antithrombin complex (TAT), as a coagulation marker, were measured. Results  The activity of the coagulation system was higher than that of the fibrinolytic system. The concentration of TAT tended to increase (3rd vs 4th postoperative day [POD], P = 0.0907). The mean time of appearance and disappearance of postoperative AAL was 1.4 days and 3.2 days, respectively. The patients with postoperative AAL had a TAT level significantly below the average on the 3rd POD in comparison to the patients without postoperative AAL (P = 0.0163). Moreover, the concentration of TAT in patients with postoperative AAL was significantly lower than that in patients without postoperative AAL (1824.0 ± 137.3 ng/ml vs 3444.0 ± 287.6 ng/ml, P = 0.0113) on the 3rd POD. On the 4th POD, the concentration of TAT was almost same and there was no significance (P = 0.6759). Conclusions  This study demonstrated for the first time the course of the fibrinolytic and coagulation activity in the pleural effusion after a pulmonary lobectomy, and showed that the delayed activity of the coagulation system is associated with the appearance of the postoperative AAL.  相似文献   
996.
This Classic article is a reprint of the original work by William Arbuthnot Lane, The Operative Treatment of Fractures. An accompanying biographical sketch on William Arbuthnot Lane, M.S., F.R.C.S., is available at DOI  10.1007/s11999-009-0861-3. The Classic Article is ©1909 by Wolters Kluwer Health-Lippincott Williams &; Wilkins and is reprinted with permission from Lane WA. The operative treatment of fractures. Ann Surg. 1909;50:1106.  相似文献   
997.
Obtaining symmetric and balanced gaps under equilateral loads is a common goal in posterior cruciate ligament (PCL)-retaining and -sacrificing TKAs. Owing to limitations in existing surgical tensors, however, tensing knee ligaments with standardized and symmetric loads has been possible only with the patella subluxated or everted. We therefore determined the influences of (1) patellar eversion versus complete reduction, (2) PCL resection, and (3) load magnitude on gap symmetry and balance in the anterior cruciate ligament (ACL)-deficient knee. We used a novel computer-controlled tensioner to measure gaps in 10 cadavers with an applied force of 50 N, 75 N, and 100 N per side. Gap data were acquired at 0o, 30o, 60o, 90o, and 120o flexion with the patella reduced and everted and with the PCL intact and resected. Everting the patella tightened the medial and lateral flexion gaps between 90o and 120o by 0.7 mm to 2.7 mm. PCL resection increased gaps from 30° to 120° by 1 mm to 3 mm. Increasing the force from 50 N to 100 N increased the mean gap by 0.5 mm. Everting the patella and resecting the PCL influenced gap balance and symmetry. Surgeons should be aware of how these conditions affect gaps during assessment and balancing. Richard Laskin—Deceased. One of the authors (CP) is employed by Praxim Inc, Walpole, MA. Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was obtained.  相似文献   
998.
Chemoradiotherapy has become a popular definitive therapy among many patients and oncologists for potentially resectable esophageal carcinoma. Although the complete response rates are high and short-term survival is favorable after chemoradiotherapy, persistent or recurrent locoregional disease is quite frequent. Salvage surgery is the sole curative intent treatment option for this course. As experience with definitive chemoradiotherapy grows, the number of salvage surgeries may increase. Selected articles about salvage esophagectomy after definitive chemoradiotherapy for esophageal carcinoma are reviewed. The number of salvage surgeries was significantly lower than the number of expected candidates. To identify candidates for salvage surgery, patients undergoing definitive chemoradiotherapy should be followed up carefully. Salvage esophagectomy is difficult when dissecting fibrotic masses from irradiated tissues. Patients who underwent salvage esophagectomy had increased morbidity and mortality. Pulmonary complications such as pneumonia and acute respiratory distress syndrome were common. The anastomotic leak rate was significantly increased because of the effects of the radiation administered to the tissues used as conduits. The most significant factor associated with long-term survival appeared to be complete resection. However, precise evaluation of resectability before operation was difficult. Nevertheless, increased morbidity and mortality will be acceptable in exchange for potential long-term survival after salvage esophagectomy. Such treatment should be considered for carefully selected patients at specialized centers. This review was submitted at the invitation of the editorial committee.  相似文献   
999.
An 89-year-old woman with dyspnea and disturbed consciousness due to hypoventilation was admitted to our hospital. Chest radiography showed no abnormal shadow, but she was intubated for deteriorated hypoventilation. Bronchoscopy demonstrated obstruction of the left main bronchus at the carina. Computed tomography (CT) showed neither a mass lesion in the mediastinum nor an aortic aneurysm, but compression of the airway by the ascending aorta was observed. It was thought that the patient’s thin thoracic cage was unable to support the weight of the ascending aorta, which consequently compressed the left main bronchus. After inserting stents into both main bronchi, the patient’s consciousness improved, and respirator support was withdrawn. In aged, bedridden, thin patients with hypopnea or recurrent airway infection, CT and bronchoscopy should be performed to investigate airway patency.  相似文献   
1000.
We report a rare case of biphasic pulmonary blastoma (BPB) with rapid progression in a 75-year-old man. Computed tomography (CT) of the chest revealed a well-defined tumor shadow measuring 8 × 6 cm in the right upper lobe. CT-guided lung biopsy revealed malignant cells with sarcomatous elements. Right upper lobectomy and systemic lymph node dissection with chest wall resection were performed. Histopathologically, the tumor was composed of immature embryoniclike mesenchymal and epithelial components that resembled embryonic lung tissue. The final diagnosis was BPB classified as pathological stage IIB (T3N0M0). Two months later, the tumor recurred in the right supraclavicular lymph nodes. The patient died of respiratory failure due to tumor progression 7 months after surgery.  相似文献   
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