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21.
We report the anaesthetic management of an eight-year-old asthmatic boy with Bartter’s syndrome who had bilateral orchidopexy with caudal epidural analgesia. Bartter’s syndrome is a rare congenital disorder characterized by hypokalaemic hypochloraemic metabolic alkalosis, hyperaldosteronism, hyperreninaemia and hyperplasia of the juxtaglomerular apparatus of the kidneys. Characteristically, although these patients are normotensive they may be hypovolaemic. They may have unstable baroreceptor responses and show marked resistance to vasopressors. Hence, fluid, acid-base and electrolyte imbalances along with haemodynamic instability pose particular problems in their anaesthetic management. Previous case reports have described the management of these patients with general anaesthesia, our patient had his orchidopexy with caudal epidural analgesia using plain bupivacaine 0.5%. The patient was haemodynamically stable throughout surgery and was comfortable with caudal analgesia as the sole anaesthetic. Hypovalaemia, acid-base status and electrolyte imbalance were treated before instituting caudal epidural analgesia. We present this case report which describes the anaesthetic considerations in the light of the pathophysiology of Bartter’s syndrome.  相似文献   
22.
Giant cell reparative granuloma of the orbit   总被引:1,自引:0,他引:1  
PURPOSE: To report a case of giant cell reparative granuloma occurring in the orbit and to discuss its clinical, radiologic, and histopathologic characteristics in contrast with other similar lesions. METHODS: A 38-year-old man developed pain and mild proptosis of the left eye. Computed tomography and magnetic resonance imaging demonstrated an intraosseous cystic orbital mass. Excisional biopsy disclosed giant cell reparative granuloma of the orbit. RESULT: At 11 months' follow-up, the patient had normal vision, with no tumor recurrence. CONCLUSION: Giant cell reparative granuloma of the orbit is a rare benign fibro-osseous proliferation that is generally seen in young adulthood. It should be considered in the differential diagnosis of orbital fibro-osseous proliferation. Surgical excision and curettage is the therapeutic method of choice.  相似文献   
23.
A 7-year-old child presented with a severe form of Takayasu's arteritis, with two consecutive episodes involving the right testis and then the left kidney 6 months later. The renal artery obstruction was accompanied by severe hypertension. An aortography showed a complete obstruction of the left renal artery and a narrowing of the right subclavian artery. Plasma renin activity was high. Serum immunoglobulins were within the normal range, except for an increase in IgE (880 /l). Despite 4 months', treatment with antihypertensive drugs, prednisone, cyclophosphamide, and anticoagulant, the blood pressure never returned to normal and the left renal function remained completely absent. A nephrectomy was performed which immediately normalized plasma renin activity and blood pressure. The child was subsequently treated with alternateday prednisone for 3 months, alternating with 3 months of cyclophosphamide or, later, azathioprine. Persantine (dipyridamole) and acetylsalicylic acid were administered continuously. The right radial pulse returned to normal within 2 years. An 8-year follow-up failed to detect any new episode of arteritis. The right kidney showed signs of compensatory hypertrophy. Finally, a recent arteriography demonstrated not only a normal right renal artery blood flow but almost total disappearance of the right subclavian artery obstruction. However, the IgE remained abnormally high (2,023 g/l).  相似文献   
24.
PURPOSE: In dose-escalation studies of radiotherapy (RT) for non-small-cell lung cancer (NSCLC), radiation pneumonitis (RP) is the most important dose-limiting complication. Transforming growth factor-beta1 (TGF-beta1) has been reported to be associated with the incidence of RP. It has been proposed that serial measurements of plasma TGF-beta1 can be valuable to estimate the risk of RP and to decide whether additional dose-escalation can be safely applied. The aim of this study was to evaluate prospectively the time course of TGF-beta1 levels in patients irradiated for NSCLC in relation to the development of RP and dose-volume parameters. METHODS AND MATERIALS: Plasma samples were obtained in 68 patients irradiated for medically inoperable or locally advanced NSCLC (dose range, 60.8-94.5 Gy) before and 4, 6, and 18 weeks after the start of RT. Plasma TGF-beta1 levels were determined using a bioassay on the basis of TGF-beta1-induced plasminogen activator inhibitor-1 expression in mink lung cells. All patients underwent chest computed tomography scans before RT that were repeated at 18 weeks after RT. The computed tomography data were used to calculate the mean lung dose (MLD) and to score the radiation-induced radiologic changes. RP was defined on the basis of the presence of either radiographic changes or clinical symptoms. Symptomatic RP was scored according to the Common Toxicity Criteria (Grade 1 or worse) and the Southwestern Oncology Group criteria (Grade 2 or worse). Multivariate analyses were performed to investigate which factors (pre- or posttreatment TGF-beta1 level, MLD) were associated with the incidence of RP. To improve our understanding of the time course of TGF-beta1 levels, we performed a multivariate analysis to investigate which factors (pre-RT TGF-beta1 level, MLD, RP) were independently associated with the posttreatment TGF-beta1 levels. RESULTS: The pre-RT TGF-beta1 levels were increased in patients with NSCLC (median 21 ng/mL, range, 5-103 ng/mL) compared with healthy individuals (range, 4-12 ng/mL). On average, the TGF-beta1 levels normalized toward the end of treatment and remained stable until 18 weeks after RT. In 29 patients, however, TGF-beta1 was increased at the end of RT with respect to the pre-RT value. The multivariate analyses revealed that the MLD was the only variable that correlated significantly with the risk of both radiographic RP (p = 0.05) and symptomatic RP, independent of the scoring system used (p = 0.05 and 0.03 for Southwestern Oncology Group and Common Toxicity Criteria systems, respectively). The TGF-beta1 level at the end of RT was significantly associated with the MLD (p <0.001) and pre-RT TGF-beta1 level (p = 0.001). CONCLUSION: The MLD correlated significantly with the incidence of both radiographic and symptomatic RP. The results of our study did not confirm the reports that increased levels of TGF-beta1 at the end of RT are an independent additional risk factor for developing symptomatic RP. However, the TGF-beta1 level at the end of a RT was significantly associated with the MLD and the pre-RT level.  相似文献   
25.
The current study focused on a sample of adults (N = 67) experiencing bereavement following the loss of a child. The Post Traumatic Growth Inventory (PTGI) was used to assess whether bereaved parents were able to perceive benefit from their trauma, and whether there were gender differences in perception of benefit. The impact of the following variables on the PTGI was also assessed: the nature and length of time since the loss, and the age and marital status of the bereaved. The results indicated that bereaved parents do perceive benefit from their loss. However, there was poor evidence to suggest perception of benefit along gender lines. Results also indicated a potential relation between greater perception of benefit and those bereaved through illness, and more perception of benefit for the longer the time elapsed since the bereavement. Lastly, there was a tendency for younger individuals and married respondents to obtain higher scores on the PTGI.  相似文献   
26.
BACKGROUND AND PURPOSE: The low density of lung tissue causes a reduced attenuation of photons and an increased range of secondary electrons, which is inaccurately predicted by the algorithms incorporated in some commonly available treatment planning systems (TPSs). This study evaluates the differences in dose in normal lung tissue computed using a simple and a more correct algorithm. We also studied the consequences of these differences on the dose-effect relations for radiation-induced lung injury. MATERIALS AND METHODS: The treatment plans of 68 lung cancer patients initially produced in a TPS using a calculation model that incorporates the equivalent-path length (EPL) inhomogeneity-correction algorithm, were recalculated in a TPS with the convolution-superposition (CS) algorithm. The higher accuracy of the CS algorithm is well-established. Dose distributions in lung were compared using isodoses, dose-volume histograms (DVHs), the mean lung dose (MLD) and the percentage of lung receiving >20 Gy (V20). Published dose-effect relations for local perfusion changes and radiation pneumonitis were re-evaluated. RESULTS: Evaluation of isodoses showed a consistent overestimation of the dose at the lung/tumor boundary by the EPL algorithm of about 10%. This overprediction of dose was also reflected in a consistent shift of the EPL DVHs for the lungs towards higher doses. The MLD, as determined by the EPL and CS algorithm, differed on average by 17+/-4.5% (+/-1SD). For V20, the average difference was 12+/-5.7% (+/-1SD). For both parameters, a strong correlation was found between the EPL and CS algorithms yielding a straightforward conversion procedure. Re-evaluation of the dose-effect relations showed that lung complications occur at a 12-14% lower dose. The values of the TD(50) parameter for local perfusion reduction and radiation pneumonitis changed from 60.5 and 34.1 Gy to 51.1 and 29.2 Gy, respectively. CONCLUSIONS: A simple tissue inhomogeneity-correction algorithm like the EPL overestimates the dose to normal lung tissue. Dosimetric parameters for lung injury (e.g. MLD, V20) computed using both algorithms are strongly correlated making an easy conversion feasible. Dose-effect relations should be refitted when more accurate dose data is available.  相似文献   
27.
PURPOSE: To evaluate the feasibility of dose escalation in non-small cell lung cancer (NSCLC) using three-dimensional conformal radiation therapy. PATIENTS AND METHODS: The main eligibility criteria of the trial were: pathologically proven inoperable NSCLC, ECOG performance status or=grade 3 (SWOG), grade 3 early and grade 2 late esophageal toxicity or any other (RTOG) grade 3 or 4 complications). RESULTS: Fifty-five patients were included. Tumor stage was I/II in 47%, IIIA in 33% and IIIB in 20%. The majority of the patients received a dose of 74.3 Gy (n=17) or 81.0 Gy (n=23). Radiation pneumonitis occurred in seven patients: four patients developed a grade 2, two patients grade 3 and one patient a grade 4. Esophageal toxicity was mild. In 50 patients tumor response at 3 months follow-up was evaluable. In six patients a complete response was recorded, in 38 a partial response, five patients had stable disease and one patient experienced progressive disease. Only one patient developed an isolated failure in an uninvolved nodal area. So far the radiation dose was safely escalated to 87.8 Gy in group 1 (lowest rMLD), 81.0 Gy in groups 2 and 3 and 74.3 Gy in group 4. CONCLUSION: Three-dimensional conformal radiotherapy enables significant dose escalation in NSCLC. The maximum tolerable dose has not yet been reached in any risk group.  相似文献   
28.
Nephron tubular epithelium possesses the capacity of adaptation to any salt ingestion condition. The mechanism of adaptation is due in part to an increase in the activity of Na(+):K(+):ATPase at the basolateral membrane. The goal of the present study was to analyze the long-term regulation of the Na(+):K(+):ATPase alpha(1)-subunit mRNA expression during changes in NaCl metabolism.Male Wistar rats given a normal, high, or low NaCl diet, and intraperitoneal administration of the loop diuretic furosemide from 12 h to 7 days were studied. Rats were kept in metabolic cages 4 days before and throughout the study to determine daily urinary electrolyte excretion and osmolarity. At the end of each experimental period, creatinine clearance and serum electrolytes were also measured. Total RNA was extracted from each individual cortex or outer medulla and from pooled inner medullas using the guanidine/cesium chloride method. Na(+):K(+):ATPase alpha(1)-subunit mRNA expression was assessed by nonradioactive dot-blot analysis.Experimental maneuvers were well tolerated and all groups developed the appropriate renal response to each experimental condition. Urinary sodium excretion was significantly higher in rats administered a high sodium diet or furosemide and lower in rats treated with a low sodium diet after 7 days of treatment. Glomerular filtration rate was similar among all groups. However, the level of expression of the Na(+):K(+):ATPase alpha(1)-subunit did not change in any model.Nephron adaptation to the modification in NaCl intake or furosemide administration over 7 days did not include changes in Na(+):K(+):ATPase alpha(1)-subunit mRNA levels.  相似文献   
29.
BACKGROUND: The present study was carried out to investigate the functional significance of the reduced dopaminergic tone in subjects affected with polycystic ovary syndrome (PCOS). METHODS: Our group evaluated the response of pituitary PRL, LH, FSH, and TSH to the administration of a single 10-mg oral dose of the dopamine (DA) receptor antagonist metoclopramide in lean (n = 7) and obese (n = 8) PCOS women and in 11 regularly cycling age- and weight-matched controls (six lean and five obese). In addition, circulating PRL bioactivity was evaluated by its mitogenic activity on a lymphoma cell bioassay. RESULTS: Oral administration of metoclopramide resulted in a significant increase in serum PRL in all subjects; however, the highest increments, regardless of body mass index (BMI), were observed in control women (p <0.005). Measurements of PRL mitogenic activity on the Nb2 lymphoma cell bioassay revealed a significant increase in the bioactive/immunoreactive (B/I) ratio of PRL under basal and stimulated conditions in obese PCOS subjects (p <0.05). Mean fasting glucose/insulin and glucose/insulin-AUC ratios were significantly lower (p <0.001) in obese PCOS when compared with all other groups. CONCLUSIONS: These data support the existence of low DA hypothalamic tone in PCOS women that is likely involved in the inappropriate LH and PRL secretion frequently seen in this syndrome. In addition, our results suggest changes in PRL bioactivity in obese PCOS that may play a role in the development of hyperinsulinemia; however, whether PRL has a functional significance in the development of the metabolic disturbances frequently seen in PCOS remains to be elucidated.  相似文献   
30.
This study was conducted to evaluate the dermal absorption of arsenic from residues present on the surface of wood preserved with chromated copper arsenate (CCA). The research reported herein used methods parallel to those of earlier research on the dermal absorption of radiolabeled arsenic (R. C. Wester et al., 1993, Fund. Appl. Toxicol. 20, 336-340), with modifications to allow use of environmental matrices that are not radiolabeled. These modifications include the surface area of application and dietary intake of arsenic, thus maximizing the potential for detection of dermally absorbed arsenic in exposed animals above diet-associated background levels of exposure. Two forms of arsenic were administered in this work. The first, arsenic in solution, was applied to the skin of monkeys to calibrate the model against prior absorption research and to serve as the basis of comparison for absorption of arsenic from CCA-treated wood residues. The second substrate was residue that resides on the surface of CCA-treated wood. Results from this research indicate that this study methodology can be used to evaluate dermally absorbed arsenic without the use of a radiolabel. Urinary excretion of arsenic above background levels can be measured following application of soluble arsenic, and absorption rates (0.6-4.4% absorption) are consistent with prior research using the more sensitive, radiolabeled technique. Additionally, the results show that arsenic is poorly absorbed from CCA-treated wood residues (i.e., does not result in urinary arsenic excretion above background levels).  相似文献   
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