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1.
Objective: Trans-sphenoidal surgery is often combined with other approaches for the treatment of middle cranial base tumors. By combining a maxillotomy with trans-sphenoidal approach, significantly wider exposure to these regions is gained. However, endoscope-assisted techniques have also been used for sellar and parasellar and upper clival regions. Methods: An extended trans-sphenoidal approach was performed on 10 cadaver heads using the operating microscope and was repeated with a 0-degree endoscope. The mean horizontal and vertical distances were measured and pictured for each technique, and both distances were compared using a parametric paired Student's t-test. Results: The mean horizontal distances in the 10 specimens were 19.5 ± 1.8 mm by microscope and 27.5 ± 2.2 mm by endoscope, and the mean vertical distances were 25.8 ± 1.9 mm by the microscope and 34.5 ± 3.5 mm by the endoscope. Conclusion: The aim of this study was to quantify the amount of exposure obtained with an extended trans-sphenoidal approach and to compare both endoscopic and microscopic techniques. Using the endoscope in conjunction with the operating microscope may provide additional exposure and better access in skull base surgery.  相似文献   
2.
Summary The effects of pineal gland, an endocrine organ known to affect the physiology of various organs and systems including the hypothalamo-hypophyseal axis, on the morphological characteristics of target organs were investigated in rats after pinealectomy and foetal pineal gland transplantation to a subpial cortical area close to the pinealectomized region.It was demonstrated that weight gain was significantly slower in pinealectomized male rats (p<0.01); pituitary gland weight was lower in the pinealectomized group (p<0.01) and transplantation had no effect on the weight of this organ; weight of adrenal gland and testis were lower after pinealectomy (p<0.01) but restored back to control levels after transplantation; the mitotic activity in seminiferous tubules increased with pinealectomy and returned back to control indexes after transplantation.Research on hypothalamic catecholaminergic content revealed a diminished histofluorescence in pinealectomized rats which showed a potentiated restoration after transplantation.The innervation of the pineal gland was studied by anterograde and retrograde injections of Wheat Germ Agglutinin Horse Radish Peroxidase from superior cervical ganglion and pineal gland, respectively. It was demonstrated that cell bodies were traced both at the transplanted tissue and hypothalamus.In view of these data, the multifunctional and a probable high level homeostatic harmony regulator essence of pineal gland is discussed.The paper has been awarded the 1993 Upjohn prize for Neurosurgical Research of the European Association of Neurosurgical Societies.  相似文献   
3.
A 4-year-old girl presented with an intramedullary epidermoid cyst of the cervical spinal cord. The clinical, radiological, and surgical features and a brief critical review of the literature are included in this report. The cyst contents were removed totally in two operations. The child had a coexisting neuroenteric cyst in the posterior mediastinum. To our knowledge, this coexistence has not been previously reported. Contemporary imaging modes and prospects of the surgical treatment are discussed.  相似文献   
4.
The effects of n-3 fatty-acid supplementation on serum lipids, platelet aggregation, and the development of atherosclerotic lesions were studied in the cholesterol-fed rabbit. Serum total cholesterol and LDL cholesterol values were significantly reduced in comparison with those of the nonsupplemented cholesterol-fed group (p less than 0.005, p less than 0.0025, respectively), though still higher than those of the control group (p less than 0.0025, p less than 0.0125 respectively). Platelet aggregation was reduced below that of the cholesterol-fed and the control levels (p less than 0.0005, p less than 0.0025, respectively). The endothelial injury encountered in cholesterol-fed rabbits was inhibited in the supplemented group. It is concluded that n-3 fatty acids suppress atherogenesis in this animal model by interfering with platelet aggregation and lipid metabolism.  相似文献   
5.
The Harmonized Alert Sensing Technology (HASTE) device was developed to overcome the primary shortcomings of interval based noninvasive blood pressure (BP) monitoring. This study was conducted to assess the reliability of the HASTE system compared with standard cuff BP values in patients on hemodialysis. A total of 1,370 HASTE measurements were compared with oscillometric standard cuff systolic BP values in 42 sessions of 15 patients on hemodialysis. The average discrepancy between the HASTE and cuff systolic BP was 1.41 +/- 16.90 mm Hg. Compared with cuff measurements, 31% of systolic BP fell within a range of 5 mm Hg difference, 57% of systolic BP fell within 10 mm Hg, and 73% of systolic BP fell within a 15 mm Hg band. According to British Hypertension Society standards or Association for the Advancement of Medical Instrumentation criteria, the current HASTE method did not perform well. Technology to provide noninvasive hemodynamic monitoring is, however, in its developmental stage. The effort at continuous systolic pressure monitoring using existing, readily available, and frequently used techniques is exciting. Although the HASTE system as currently configured and calibrated did not adequately perform, variations in site analysis and conversion factors may increase pressure sensitivity and tracking over the course of a standard dialysis treatment.  相似文献   
6.
To compare retrospectively the recurrence rates of TUR alone versus different intravesical chemotherapy modalities in superficial bladder cancer cases, 187 patients with stage Ta and T1 bladder tumours were treated with transurethral resection followed by adjuvant intravesical chemotherapy with mitomycin, BCG or epirubicin or by transurethral resection alone. All patients in this study had historically proven transurethrally resectable primary, category Ta and T1 transitional cell carcinoma (TCC) of the bladder. Group I included transurethral resection alone, and the other groups included intravesical mitomycin-C(Group II), BCG (Group III) and epirubicin (Group IV) therapies after transurethral resection. 146 male and 41 female patients (78% male and 22% female patients) in this study were diagnosed as primary TCC bladder tumours. Only 52 of them were stage Ta and 135 of them were stage T1 bladder tumours. Examining the histological grade of the bladder tumours, 88 (47%) of the patients had grade I, 53 (28%) had grade IIa, 30 (16%) had grade IIb and remaining 16 (9%) had grade III bladder cancers. The recurrence rates were 25% for Group I, 23.8% for Group II, 26.2% for Group III and 22.7% for Group IV. These values were given with disregarding the grade and volume of the bladder tumours. For solitary, less than 3 cm low grade tumours (grade I, IIa) recurrence rates were 16% for Group I, 15.4% for Group II, 17.8% for Group III, 17.2% for Group IV (p> 0.05). As a result of this retrospective study, for patients with low grade, stage Ta and T1 tumours TUR alone may be the best treatment modality. Although intravesical chemotherapy is effective in decreasing short-term incidences of tumour recurrence, it has not decreased long-term incidences of tumour recurrence. The high cost and adverse side effects of intravesical chemotherapy should also be taken into consideration in superficial, single, low grade tumours of bladder. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
7.
Summary ? Background. Cerebral vasospasm after subarachnoid hemorrhage (SAH) has remained a major cause of morbidity and mortality in patients with SAH. Excitatory neurotransmitters are gathered in the extracellular space during ischemia due to cerebral vasospasm and initiate or stimulate a series of pathophysiological biochemical processes which consequently lead to neuronal death. Tizanidine (Sandoz compound DS 103–282, 5-chloro-4,2 (2-imidazolin-2-yl-amino)-2,1,3-benzothiazol hydrochloride) is a centrally-acting muscle relaxant and a selective α 2 adrenoreceptor agonist which shows its effect by stimulating presynaptic α 2 adrenoreceptors in central ASPergic and GLUergic system by inhibiting aspartic acid and glutamic acid release. In this study, the effect of Tizanidine on vasospasm was evaluated.  Methods. We used a femoral artery vasospasm model in rats which has been described by Okada et al. 60 rats were examined in three groups. The first group was used as control group (Control) (n=20), in the second group subarachnoid hemorrhage was performed (SAH) (n=20), in the third group Tizanidine was administered in addition to SAH (SAH+Tizanidine administration) (n=20). Animals in SAH+Tizanidine administration group received 0,3 mg/kg/day intraperitoneally for 7 days. Seven days after the experiment, after perfusion-fixation, 10 mm segments of both femoral arteries were removed and the femoral artery was prepared for light microscope examination, scanning and transmission electron microscopy and for morphometric analysis.  Results. There was a statistically significant difference between the electron, scanning and light microscopic observations and morphometric analysis of SAH+Tizanidine administration group and SAH group, and no statistically significant difference between SAH+Tizanidine administration group and control group.  Conclusion. This study has disclosed that Tizanidine administration before the vasospasm reduces ultrastructural and morphometric vasospastic insult significantly. However, the clinical application of Tizanidine as a protective and therapeutic agent in cerebral vasospasm needs further studies including the employment of clinically more relevant SAH models.  相似文献   
8.
9.
The fact thatH. pylori gastritis results in an increased secretion of basal and meal-stimulated gastrin, which is also a physiologic amplifier of insulin release directed us to investigate whetherH. pylori gastritis may lead to an enhancement of nutrient-stimulated insulin secretion. For this purpose, we have investigated the insulin responses to both oral glucose and a mixed meal in 15 patients withH. pylori gastritis before and one month after the eradication therapy and also in 15H. pylori-negative control subjects. The areas under the curve (AUC) for serum insulin following both oral glucose and a mixed meal in the patients withH. pylori gastritis before the eradication were significantly (P<0.05) higher than those in theH. pylori-negative controls. After the eradication ofH. pylori, the AUC for serum insulin following oral glucose and mixed meal decreased by 9.4% and 13.1%, respectively (P<0.001 in both), and serum basal and meal-stimulated gastrin levels decreased significantly (P<0.001). These results suggest thatH. pylori gastritis enhances glucose and meal-stimulated insulin release probably by increasing gastrin secretion.Presented in part as an abstract at the 8th Balkan Congress of Endocrinology, Bursa, Turkey, May 3–5, 1995.  相似文献   
10.

Purpose

The aim of our study is to research the role and efficacy of cerebral oximetry in predicting neurologic prognosis when applied during TTM to patients experiencing coma after CA.

Methods

This study was performed on surviving adult comatose patients after CA treated with TTM. The average scores of rSO2 was measured at 6 h intervals for the first 2 days and once a day for the following 3 days with a NIRS device during TTM. The CPC scale was used to define the neurologic outcomes of patients. We compared the correlations of rSO2 values between good (CPC 1–2) and poor (CPC 3–5) neurologic outcomes in CA patients.

Results

There was no statistically significant difference identified between the prognosis groups in terms of rSO2, CPR durations, hemoglobin values and admission body temperature (p > 0.05). When the variation in rSO2 values over time is investigated, though there was no significant difference between the good and poor prognosis groups, it appeared to fall in the first 6 h in both prognosis groups. The median NT-proBNP and lactate values were observed to be higher in the poor prognosis group.

Conclusion

There is no significant correlation between rSO2 values and neurologic outcomes. Multimodal monitoring methods may be useful and further studies with a larger patient population are necessary in this area.  相似文献   
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