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41.
OBJECTIVE: Former studies have pointed out that hemodynamic stress imposed by associated valvular disease is the primary factor in the development of ascending aorta dilatation. At present, intrinsic wall pathology is blamed for dilatation and aneurysm formation in bicuspid aortic valve (BAV). MATERIALS AND METHODS: Aortic valve replacement (AVR) was performed on 78 adult patients with BAV. Patients were divided into two groups. Group I (n = 27) underwent only AVR. Group II (n = 51) underwent AVR and additional ascending aorta procedures such as Shawl-Lapel aortoplasty (n = 12) and tailoring aortoplasty (n = 9). Dacron wrapping was performed after both techniques were done. Ascending aorta replacement was done on 11 patients by using composite graft. Supracoronary graft replacement was performed in 3 patients after AVR. RESULTS: Ascending aorta diameter increment was 1.25 mm/year in normotensive and 2.80 mm/ year in hypertensive patients. Ascending aorta aneurysm (diameter > 55 mm) developed in eight patients in the postoperative period in group I. Ascending aorta dilatation did not develop in group II patients. Mean survival time +/- standard error (SE) was 128 +/- 11 and 99 +/- 4 months and survival possibility was 77.78% and 92.16%. Freedom from reoperation was 65.4% and 95.9% in 8 years in group I and group II, respectively. CONCLUSION: Aortic wrapping with or without aortoplasty has a beneficial effect not only in dilated ascending aorta but also in all nondilated BAV patients with normal-sized aortic diameter. Ascending aorta wrapping in BAV patients preserves the endothelial lining and prevents further dilatation, aneurysm formation, and dissection.  相似文献   
42.
BACKGROUND: Pseudoaneurysms (PsAns) of the popliteal and tibioperoneal arteries are very rare and occur as a late complication after arterial injury. This study was undertaken to describe the management of PsAns of the popliteal and tibioperoneal arteries after gunshot injuries in a civilian vascular surgical unit with a large trauma workload. METHODS: A retrospective review of the records of nine patients treated between January 1998 and November 2001 at the Thoracic and Cardiovascular Surgery Department of Numune Education and Research Hospital was undertaken. RESULTS: Nine PsAns of the popliteal and tibioperoneal arteries after gunshot injuries were treated. The delay in diagnosis from the time of injury ranged from 15 days to 14 months, with a median delay of 75 days. One case with graft occlusion was noticed in a patient with a popliteal artery PsAn. In these cases, the early and late patency rate and limb salvage were 100%. CONCLUSION: Early diagnosis of popliteal and tibioperoneal PsAns is an important factor in successful surgical reconstruction. The operative procedures will be simple if the interval between injury and operation is short, and surgical treatment for PsAns includes reconstruction of both arterial and venous arteries.  相似文献   
43.
Adductor paralysis or the pathologies occurring after laryngeal surgery such as scarring or atrophy of the vocal cords cause glottic insufficiency during phonation. Injection laryngoplasty has been a widely accepted technique due to lower morbidity of the procedure and the applicability via endoscope in the treatment of these pathologies. Various materials have been used in injection laryngoplasty. The primary expectations in these techniques are the persistence of injected material long enough, without resorbtion or any cause of serious tissue response and having beneficial effects in reinforcing the glottic tissue. In the present study, we used large molecular-sized calcium hydroxyl-apatite (CaHA) particles in injection laryngoplasty to observe the effects of the material in the laryngeal tissues under the light microscopic examination. The study was performed on 12 rabbits in four groups. After injecting Ca10 (PO4)6(OH)2 (Coaptite®) into their vocal folds, the rabbits were killed at certain intervals, in the 1st week (group 1) in the 1st month (group 2) in the 3rd month (group 3) and in the 6th month (group 4). Larynges were removed and processed for light microscopic observations. Our observations revealed that this material induced the new cartilage formation without a serious tissue response in the larynges. Formation of a new cartilage tissue was the most significant, but an unexpected outcome of the study. The injected material inducing a neocartilage formation without any tissue reaction persisted long enough in the laryngeal tissues. Although neocartilage formation may interfere the vocal fold vibrations, providing glottic closure in the phonation with a durable material will be an important gain.  相似文献   
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45.
OBJECTIVE: The aim of this study is to evaluate the efficacy of intraperitoneal cisplatin as consolidation treatment in epithelian ovarian cancer patients with complete pathologic response following front-line platin-based chemotherapy. PATIENTS AND METHODS: Thirty patients who had no evidence of disease as assessed by second-look laparotomy following chemotherapy for stage III epithelial ovarian cancer were given three courses of intraperitoneal cisplatin (100 mg/m(2)) with three weekly intervals as consolidation therapy. RESULTS: Median age was 50 years. After a median follow-up period of 37 months, 16 patients are being followed with no evidence of disease. Eleven patients developed recurrent disease. Median disease-free survival was 50 months. Median overall survival is not reached. WHO grades 3-4 toxicity criteria were emesis in 19 patients (63.3%), abdominal pain in 5 (16.7%) and nephrotoxicity in 2 (6.7%) patients. Catheter-related complications were infection/peritonitis in one and catheter malfunction in one patient. There were no serious hematologic side effects that required transfusions or caused treatment delays. None of the patients developed serious neurologic toxicity. Treatment had to be stopped early in four patients who refused further treatment due to abdominal pain, nausea ::and vomiting. Dose reductions were required in five patients.CONCLUSION: Our results suggest that intraperitoneal cisplatin is a feasible regimen that may provide a favorable outcome in terms of progression-free survival in patients with a complete pathologic response following front-line treatment for ovarian cancer. Further randomized trials are required to evaluate the role of consolidation treatment in this setting.  相似文献   
46.
Laboratory research on ovarian cryopreservation and transplantation began in the 1950s leading to clinical studies in the 2000s. The research that was performed during this half century indicated that cryopreserved ovarian tissue has the potential to restore fertility in women who face premature ovarian failure due to chemotherapy, radiotherapy or surgery. To date, ovarian function has been restored in at least four women. Even though no pregnancies have been reported so far from these clinical studies, animal studies indicate that this is a valid prospect for humans. Future clinical trials will determine on a larger number of patients the longevity of ovarian grafts, normality of hormone production and ovarian follicle development, possibility and safety of pregnancy, and the safety of auto-transplantation in cancer patients. However, the major improvement in the efficiency of ovarian transplantation is anticipated to come from research exploring the revascularization process.  相似文献   
47.
OBJECTIVE: To examine the use of a radial artery graft for bypass of the maxillary artery (MA) to proximal posterior cerebral artery (PCA) as an alternative to the external carotid artery (ECA) to PCA anastomosis used in posterior circulation bypass surgery. MATERIALS AND METHODS: The method was applied to five adult cadaver sides bilaterally. The MA was easily found 1-2 cm beneath the infratemporal crest after a frontotemporal craniotomy and a zygomatic arch osteotomy. Extradurally, 2-3 cm posterolateral to the foramen rotundum, a hole was drilled in the sphenoid bone with a 4-mm tipped drill. After sylvian fissure, the interpedincular and ambient cisternae were opened and the P2 segment of the PCA appeared. The graft was passed through the hole and dura to reach the P2 segment. Proximal to the infraorbital artery branch, the MA was freed from the surrounding tissue and transected. The proximal side of the radial artery graft was anastomosed end-to-end with the MA and the distal side was anastomosed end-to-side with the P2 segment of the PCA. RESULTS: The average diameter of the MA proximal to the infraorbital artery branch was 2.6+/-0.3 mm. The average diameter of the P2 was 2.2+/-0.2 mm. The average length of the graft was 47+/-5.2 mm. CONCLUSION: As MA to proximal PCA bypass uses a short radial graft and as the calibers of the MA and PCA are >2 mm such a bypass may provide sufficient blood flow and represents a reasonable alternative to "ECA to PCA" bypass.  相似文献   
48.
BACKGROUND: We aimed to investigate effects of low dose ketamine before induction on propofol anesthesia for children undergoing magnetic resonance imaging (MRI). METHODS: Forty-three children aged 9 days to 7 years, undergoing elective MRI were randomly assigned to receive intravenously either a 2.5 mg x kg(-1) bolus of propofol followed by an infusion of 100 microg x g(-1) x min(-1) or a 1.5 mg x kg(-1) bolus of propofol immediately after a 0.5 mg x kg(-1) bolus of ketamine followed by an infusion of 75 microg x kg(-1) x min(-1). If a child moved during the imaging sequence, a 0.5-1 mg x kg(-1) bolus of propofol was given. Systolic and diastolic blood pressures, heart rate, peripheral oxygen saturation and respiratory rates were monitored. Apnea, the requirement for airway opening maneuvers, secretions, nausea, vomiting and movement during the imaging sequence were noted. Recovery times were also recorded. RESULTS: Systolic blood pressure and heart rate decreased significantly in the propofol group, while blood pressure did not change and heart rate decreased less in the propofol-ketamine group. Apnea associated with desaturation was observed in three patients of the propofol group. The two groups were similar with respect to requirements for airway opening maneuvers, secretions, nausea-vomiting, movement during the imaging sequence and recovery time. CONCLUSIONS: Intravenous administration of low dose ketamine before induction and maintenance with propofol preserves hemodynamic stability without changing the duration and the quality of recovery compared with propofol alone.  相似文献   
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50.
BACKGROUND: Smear-negative pulmonary tuberculosis (SNPTB) constitutes a major problem in countries with a moderate or high TB prevalence. The value of high-resolution computed tomography (HRCT), chest x-ray and other clinical findings in determining activity of SNPTB were investigated. METHODS: The study population consisted of 85 patients with suspected SNPTB, of whom 52 were confirmed as active pulmonary TB according to either culture positivity for Mycobacteriun tuberculosis or demonstration of caseous granulomatous inflammation. The remaining 33 patients accepted inactive TB sequel. RESULTS: Cough and expectoration were significantly frequent in inactive group whereas chest pain was detected higher in active patients. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of HRCT in detecting disease activity were 88, 88, 92, 83 and 88%, respectively. Centrilobular nodules, other non-calcified nodules, consolidation and cavity were significantly higher on HRCT in active group. Chest x-ray scores that were graded 1 to 3 showed a linear trend for the disease activity. CONCLUSIONS: HRCT has good diagnostic value in detecting activity of SNPTB, and some clinical findings may help in predicting the activity.  相似文献   
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