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81.
Sabahat Inanir Mustafa Ünlü Berna Okudan Erdal Cila Sahap Atik 《European journal of nuclear medicine and molecular imaging》1996,23(8):987-990
Radiolabelled somatostatin analogues are of potential value in the imaging of somatostatin receptor-positive tumours. Recently, somatostatin receptors have been demonstrated in the osteoblast precursor cells. In this preliminary study, we evaluated the uptake characteristics of indium-111 octreotide in two benign and two malignant bone tumours. Tracer accumulation was observed in all four cases, and overall lesion to background ratio (mean±SD) was 2.74±0.84 and 2.98±1.49 at 4 h and 24 h, respectively. There was no clear relationship between I111In-octreotide accumulation and the benign or malignant nature of the tumour. In one patient, tracer uptake was inhibited by unlabelled octreotide administration. These results suggest that111In-octreotide can be taken up by benign and malignant bone tumours. The inhibition of tumour uptake by treatment with cold octreotide supports the concept that specific uptake mechanisms are responsible for111In-octreotide deposition by bone tumours. 相似文献
82.
BACKGROUND: There is increasing evidence to suggest that toxic oxygen radicals play a role in the pathogenesis of ischemia/reperfusion (I/R) injury in the kidney. The aim of this study was to evaluate whether quercetin, an oxygen free radical scavenger, protects kidney tissue. METHODS: A renal I/R injury was induced by a left renal pedicle occlusion by ischemia for 45 min, followed by 60 mins of reperfusion with contralateral nephrectomy in rats. The rats were pretreated intraperitoneally with a quercetin suspension (50 mg/kg) 60 min before the ischemia induction. Thiobarbituric acid reactive substances (TBARS), protein carbonyl content, tumor necrosis factor alpha (TNF-alpha), reduced glutathione (GSH) levels, myeloperoxidase (MPO) catalase (CAT) and superoxide dismutase (SOD) activities were determined in renal tissue. RESULTS: There were 3 groups of rats, the control group, the I/R group and the I/R+Q group. Our results indicate that TBARS, TNF-alpha levels, MPO activity and protein carbonyl content were significantly higher in the I/R group than those in the control group (p<0.05, p<0.01, p<0.01 and p<0.01, respectively). Quercetin administration significantly decreased these parameters (p<0.05, p<0.01, p<0.05 and p<0.01, respectively). GSH levels, SOD, and CAT activities significantly decreased after I/R injury when compared to the control group (p<0.01, p<0.05 and p<0.01, respectively). Quercetin treatment significantly increased GSH levels and activities of these enzymes when compared to the I/R group (p<0.05, p<0.01, p<0.05, respectively). CONCLUSIONS: These results suggest that quercetin reduces renal oxidative injury and facilitates repair. Quercetin can have a role in a renoprotective therapeutic regimen. 相似文献
83.
OBJECTIVE: Bone metastasis is a major cause of morbidity in prostatic cancer. Therefore, detecting and monitoring bone lesions are crucial for treatment of prostatic carcinoma. We aimed to evaluate total body bone mineral density and regional bone mineral density in patients with prostate cancer with and without metastases, and to compare them with bone scintigraphy. METHODS: Fifty-four patients with prostatic carcinoma and 20 healthy subjects were investigated with bone scintigraphy and dual-energy X-ray absorptiometry. The bone scintigraphic findings were classified as normal (score 0: n = 22), abnormal but not typical for metastases (score 1: n = 18), and typical pattern of metastases (score 2: n = 14). RESULTS: The patients with bone metastases prostate cancer had significantly higher total bone mineral density and regional bone mineral density of trunk and pelvis than healthy controls and prostate cancer patients without bone metastases. There was a significant positive correlation between bone scan score and total bone mineral density and regional bone mineral density of trunk and pelvis (r = 0.328, P < 0.05, r = 0.60, P < 0.001, r = 0.480, P < 0.001, respectively). CONCLUSION: Our results show that patients of prostate cancer with bone metastases have increased bone mineral density (BMD) in the pelvis and trunk, possibly because of a predominance of osteoblastic over osteolytic metastases demonstrated by Tc-99m MDP bone scan. 相似文献
84.
Kurukahvecioglu O Sare M Karamercan A Gunaydin B Anadol Z Tezel E 《Surgical endoscopy》2008,22(4):907-911
Background Pneumoperitoneum causes intracranial pressure elevation and blood stasis at lower extremities. This study investigates cerebral
oxygen saturation changes during laparoscopy and the effects of intermittent sequential compression (ISC) of the lower extremities
in patients during elective laparoscopic cholecystectomy.
Patients and method Sixty patients were randomly divided into two groups according to the application of ISC to the lower extremities. Group I
served as control group whereas ISC was applied to group II. Cerebral oxygen saturation, peripheral blood oxygen saturation,
heart rate, mean blood pressure, and associated changes have been recorded during the operation.
Results Peripheral blood oxygen saturation and mean blood pressure values did not change significantly after pneumoperitoneum. Cerebral
oxygen saturation levels of the group II patients were higher in than the group I patients and the difference between the
groups was statistically significant (p = 0.0001). The difference became more prominent following the 35th minute of the operation. Mean heart rate of the patients in group II was lower than the patients in group I and the difference
was also statistically significant (p = 0.0001).
Conclusion In this study, it was found that the decrease in cerebral oxygen saturation was recovered with ISC application. This simple
and reliable technique helps to restore cerebral oxygen saturation levels while increasing blood return from the lower extremities. 相似文献
85.
Erdem AF Yoruk O Alici HA Cesur M Atalay C Altas E Kursad H Yuksek MS 《Paediatric anaesthesia》2008,18(9):878-883
Background: Postoperative vomiting (POV) is a common complication after tonsillectomy. Dexamethasone is known to decrease postsurgical vomiting. In this study, we compared the effects of dexamethasone alone to dexamethasone plus propofol on postoperative vomiting in children undergoing tonsillectomy. Methods: In a randomized double‐blinded study, we evaluated 80 healthy children, aged 4–12 years, who underwent tonsillectomy with or without adenoidectomy. After anesthesia was induced by inhalation of sevoflurane, 0.15 mg·kg?1 dexamethasone and 2 μg·kg?1 fentanyl was administered i.v. to all patients. The patients in the dexamethasone plus propofol group received 1 mg·kg?1 propofol before intubation and continuously after intubation at a rate of 20 μg·kg?1·min?1 until the surgery was completed. Data for postoperative vomiting were grouped into the following time periods: 0–4 and 4–24 h. Data were analyzed using a Student’s t‐test and chi‐squared analysis. Results: The percentage of patients exhibiting a complete response (defined as no retching or vomiting for 24 h) increased from 37.5% in the dexamethasone‐alone group to 75% in the dexamethasone plus propofol group (P = 0.001). Twenty‐two patients (55%) in the dexamethasone‐alone and nine patients (22.5%) in the dexamethasone plus propofol groups experienced vomited during 0–4 h (P = 0.003). Eight patients in the dexamethasone‐alone group and three patients in the dexamethasone plus propofol group received ondansetron as a rescue antiemetic during the postoperative period. Conclusion: For children undergoing tonsillectomy, intraoperative subhypnotic propofol infusion combined with dexamethasone treatment provides a better prophylaxis against postoperative vomiting than does dexamethasone alone. 相似文献
86.
Purpose
This study aimed to determine the effect of melatonin in preventing ischemia-reperfusion (I-R) injury-induced tissue damage and on spermatogenesis after experimental testicular torsion (TT).Methods
Forty peripubertal rats were divided into 4 groups each containing 10 rats: control (C), sham (S), torsion plus detorsion (TD), and torsion plus melatonin (M). The left testes were rotated 720° for 6 hours and detorsed for 6 hours thereafter. Serum inhibin B (IB) levels were measured in blood samples taken from all groups. Left orchiectomies were performed to determine the tissue levels of Johnsen's scores (JS) and malondialdehyde (MDA).Results
Serum IB levels in the S and TD groups were significantly lower compared with that in the C group, whereas they were higher in the M group compared with the TD group. The MDA levels were significantly lower in the C, S, and, M groups compared with the TD group. Johnsen's scores were significantly higher in the C, S, and M groups compared with the TD group.Conclusions
Our results suggested that melatonin is a potent antioxidant agent in preventing testicular I-R injury, as shown by increased IB levels and JS. 相似文献87.
Spontaneous rupture of the Achilles tendons in hemodialysis patients is a rare complication. The majority of these patients
have additional predisposing factors, such as previous use of fluoroquinolone antibiotics or corticosteroids. Spontaneous
rupture of bilateral Achilles tendons without any of those predisposing factors is exceptional. In this paper, we report a
43-year-old woman who had been undergoing regular hemodialysis for 16 years. She developed bilateral spontaneous and simultaneous
rupture of the Achilles tendons. She also developed pathological fracture of right femur neck 3 years later. Based on previous
cases of tendon ruptures in uremic patients and the lack of history for the use of corticosteroids or fluoroquinolones, we
believe that secondary hyperparathyroidism is the predisposing factor in this patient. 相似文献
88.
J. Lewis M. Hossain A. Mustafa A. Sinha 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2008,18(5):357-360
We present the results of prospective evaluation of digital compared to plain radiographic preoperative templating for primary
total knee replacement. All consecutive patients undergoing primary knee replacement were eligible. Patients with previous
knee replacement or without calibrated digital or plain radiographs were excluded. Plain radiographs were templated against
acetate templates. Digital images were templated with the help of commercial software TraumaCad. A 25-mm spherical metal ball
placed nearest to the affected knee joint acted as calibration object. The ICC value for intra-rater reliability was 0.846
for tibial templating and 0.840 for femoral templating. PFC sigma cruciate substituting components were implanted in all patients.
Twenty-eight consecutive patients between April 2006 and June 2007 were included. Accurate digital templating score was 80%
for tibial implant and 40% for femur. Accuracy of analog templating was 55% for tibial implant and 50% for femur. There was
no mismatch of over one size. The differences between templated and implanted sizes were plotted against their mean in Bland–Altman
plot. The 95% confidence interval of the differences between digital and actual sizes were: 0.78 to −0.75 sizes for tibial
implant and 1.15 to −0.93 sizes for femoral implant. The 95% confidence interval of the differences between plain and actual
sizes were: 0.38 to −0.99 size for tibial implant and 0.93 to −1.32 size for femoral implant. The two tailed P value for difference between digital and analog templating from a Wilcoxon matched pair signed rank test was 0.021 for tibia
and 0.006 for femur. We found preoperative templating by the operating surgeon reliable and accurate but digital templating
did not offer any additional advantage. 相似文献
89.
Aim In recent years significant progress has been made in identifying and quantitating physico-chemical processes involved in
urinary stone formation. The ability of urine to inhibit calcium oxalate crystallization is an important mechanism against
stone formation. Dietary factors appear to affect the ability of urine to inhibit calcium oxalate crystallization. These factors
encouraged us to study the effects of lemon and orange juices on calcium oxalate crystallization in vitro.
Material and methods The nucleation and aggregation of calcium oxalate monohydrate crystals were studied using turbidimetric 30-min time course
measurements of optic density at 620 nm after mixing solutions containing calcium chloride and sodium oxalate at 37°C, pH 5.7.
The formation of crystals is induced by the addition of the oxalate and calcium solution. The effects on calcium oxalate crystal
growth of trisodium citrate, lemon and orange juices were examined. The effects of lemon and orange juices were evaluated
by the addition of 50 ml of juices. The optical density is measured at physiological conditions. The maximum increase of optic
density with time, termed SN, reflects maximum rate of formation of new particles. After an equilibrium has been reached, a progressive decrease of optic
density with time is observed. Rate of aggregation, SA, is derived from the maximum decrease in optic density.
Results Among the modifiers studied, citrate decreased both SN and SA (P < 0.001). Lemon juice was also found to inhibit the rate of crystal nucleation and aggregation. But orange juice did not
have any effect on the calcium oxalate crystallization (P > 0.05).
Conclusion These results show that effective prevention of urinary stone formation should aim at restoring the urine’s ability to inhibit
calcium oxalate crystallization and more emphasis should be given to dietary measures. 相似文献
90.
Güneren E Keskin M Uysal OA Aritürk E Kalayci AG 《Journal of pediatric surgery》2002,37(11):1632-1633
An inguinal and perianal localization of Fournier's gangrene (FG) in a 15-month-old boy as a complication of the varicella infection is discussed. This is the first presentation of the disease as a complication of the varicella rashes. There were already 57 pediatric FG cases resulting from other causes that had been presented in the medical literature. 相似文献