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1.
Management of hepatitis B in China   总被引:45,自引:1,他引:44       下载免费PDF全文
Hepatitis B virus (HBV) infection is a global public health problem. According to the data of WorldHealth Organization (WHO), 2 billion people worldwide have been infected with HBV, and among them 350400 million are chronic HBV carriers. Hepatitis B causes about 1 million deaths of HBV related liver failure, cirrhosis, and hepatocellular carcinoma annually.  相似文献
2.
Background Because patients with scar contracture of the neck are at a high risk of loss of the airway control after anesthesia induction, awake intubation is usually recommended. This retrospective clinical study was designed to evaluate the possibility, safety and efficacy of airway management and tracheal intubation under general anesthesia in such patients.
Methods This retrospective study included 1683 patients from January 1994 to December 2006 with scar contracture of the neck, aged 1.5--67.0 years, who were scheduled for elective plastic surgery under general anesthesia in Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Based on the results of the preoperative airway assessment, the patients were classified into group 1 (including 1375 patients with the atlanto-occipital extension of 〉20° and the Mallampatti's grade I or II) and group 2 (containing 308 patients with the atlanto-occipital extension of 〈20° and the Mallampatti's grade III or IV. In group 1, the intravenous induction and maintenance of anesthesia and succinylcholine for muscle relaxation were used. The intubation was done using a modified Macintosh technique. In group 2, the total intravenous anesthesia (TIVA) or the sevoflurane inhalation anesthesia was chosen and the spontaneous breathing was reserved during anesthesia. The intubation was performed by a fiberoptic stylet laryngoscope (FOSL). The number of intubation attempts, intubation time and relative complications were observed and recorded in all patients.
Results In group 1, the intubation was accomplished during the first attempt in 1279 cases (93%) and the intubation time was 〈3 minutes in 1304 cases (95%). In group 2, the intubation was completed by the first attempt in 114 patients (37%) and 123 patients had an intubation time of 〈3 minutes (40%). Tracheal intubation was successful by the second or third attempt in 96 patients in group 1 and 156 patients in group 2. Thirty-eight patien  相似文献
3.
Objective To review the recent studies about human umbilical cord mesenchymal stem cells (hUCMSCs) and advances in the treatment of spinal cord injury. Data sources Published articles (1983-2007) about hUCMSCs and spinal cord injury were selected using Medline. Study selection Articles selected were relevant to development of mesenchymal stem cells (MSCs) for transplantation in spinal cord injury therapy. Of 258 originally identified articles 51 were selected that specifically addressed the stated purpose. Results Recent work has revealed that hUCMSCs share most of the characteristics with MSCs derived from bone marrow and are more appropriate to transplantation for cell based therapies. Conclusions Human umbilical cord could be regarded as a source of MSCs for experimental and clinical needs. In addition, as a peculiar source of stem cells, hUCMSCs may play an important role in the treatment of spinal cord injury. Chin Med J 2009;122(2):225-231  相似文献
4.
Background Human epidermal growth factor 2 (HER2) is one of the most important prediction factors, but only 25%-30% of breast cancer patients HER2 are positive. It is unknown whether there are other molecular markers that could be used to predict prognosis and recurrence in HER2 negative patients.This study investigated correlations of cyclin A2 and HER2 levels with clinical outcomes in 281 patients with invasive breast cancer in order to identify whether cyclin A2 can serve as a prognostic factor in HER2 negative patients. Methods Immunohistochemical staining was used to detect cyclin A2 and HER2 expression in 281 patients. Cyclin A2 and HER2 gene amplifications were analyzed using gene analysis and RT-PCR in 12 patients. Risk and survival estimates were analyzed using Log-rank, Kaplan-Meier, and Cox regression analysis; cyclin A2 and HER2 consistency with survival were analyzed using Kappa analysis. Results Patients with higher cyclin A2 and HER2 expressions had significantly shorter disease-free survival periods (P=0.047 and P=-0.05, respectively). Kappa analysis performed that cyclin A2 and HER2 showed a low Kappa index (kappa=0.37), allowing us to conclude that cyclin A2 and HER2 detect different pathologies. Gene analysis and RT-PCR showed that cyclin A2 was upregulated in patients with early relapse; the average increase was 3.69-2.74 fold. Conclusions Cyclin A2 and HER2 are associated with proliferation and high recurrence, particularly when combined. Cyclin A2 is easily detected by nuclear staining and might be a useful biomarker for recurrence risk in HER2 negative patients.  相似文献
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Calcifying tendinopathy is a tendon disorder with calcium deposits in the mid-substance presented with chronic activity-related pain, tenderness, local edema and various degrees of incapacitation. Most of current treatments are neither effective nor evidence-based because its underlying pathogenesis is poorly understood and treatment is usually symptomatic. Understanding the pathogenesis of calcifying tendinopathy is essential for its effective evidence-based management. One of the key histopathological features of calcifying tendinopathy is the presence of chondrocyte phenotype which surrounds the calcific deposits, suggesting that the formation of calcific deposits was cell-mediated. Although the origin of cells participating in the formation of chondrocyte phenotype and ossification is still unknown, many evidences have suggested that erroneous tendon cell differentiation is involved in the process. Recent studies have shown the presence of stem cells with self-renewal and multi-differentiation potential in human, horse, mouse and rat tendon tissues. We hypothesized that the erroneous differentiation of tendon-derived stem cells (TDSCs) to chondrocytes or osteoblasts leads to chondrometaplasia and ossification and hence weaker tendon, failed healing and pain, in calcifying tendinopathy. We present a hypothetical model on the pathogenesis and evidences to support this hypothesis. Understanding the key role of TDSCs in the pathogenesis of calcifying tendinopathy and the mechanisms contributing to their erroneous differentiation would provide new opportunities for the management of calcifying tendinopathy. The re-direction of the differentiation of resident TDSCs to tenogenic or supplementation of MSCs programmed for tenogenic differentiation may be enticing targets for the management of calcifying tendinopathy in the future.

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7.
Ropivacaine and levobupivacaine have been introduced into obstetric analgesic practice with the proposed advantages of causing less motor block and toxicity compared with bupivacaine. However, it is still controversial whether both anesthetics are associated with any clinical benefit relative to bupivacaine for labor analgesia. This study aimed to compare the analgesic efficacy, motor block and side effects of bupivacaine, ropivacaine and levobupivacaine at lower concentrations for patient-controlled epidural labor analgesia. Methods Four hundred and fifty nulliparous parturients were enrolled in this randomized clinical trial. A concentration of 0.05%, 0.075%, 0.1%, 0.125% or 0.15% of either bupivacaine (Group B), ropivacaine (Group R) or levobupivacaine (Group L) with sufentanil 0.5 ug/ml was epidurally administered by patient-controlled analgesia mode. Effective analgesia was defined as a visual analogue scale score was 〈30 mm. The relative median potency for each local anesthetic was calculated using a probit regression model. Parturients demographics, sensory and motor blockade, obstetric data, maternal side effects, hourly volumes of local anesthetic used, and others were also noted. Results There were no significant differences among groups in the numbers of effective analgesia, pain scores, hourly local anesthetic amount used, sensory and motor blockade, labor duration and mode of delivery, side effects and maternal satisfaction (P 〉0.05). The relative median potency was bupivacaine/ropivacaine: 0.828 (0.602-1.091), bupivacaine/levobupivacaine: 0.845 (0.617-1.12), ropivacaine/levobupivacaine: 1.021 (0.774-1.354), respectively. However, a significantly less number of effective analgesia and higher hourly local anesthetic use were observed in the concentration of 0.05% than those of 〉0.1% within each group (P 〈0.05). Conclusions Using patient-controlled epidural analgesia, lower concentrations of bupivacaine, ropivacaine and levobupivacaine with s'ufentanil produce similar analgesia and motor block and safety for labor analgesia. The analgesic efficacy mainly depends on the concentration rather than the type of anesthetics.  相似文献
8.
PolymorphismsofvitaminDreceptorgeneanditsasociationwithbonemineraldensityandosteocalcininChineseZhaoJinxiu赵金秀,ZhouXueying周学瀛,...  相似文献
9.
Background Although neurologic manifestations often complicate the course of patients with multiple myeloma, direct central nervous system invasion is rare. This study explored the neurologic symptoms, signs, clinical features, therapy and prognosis of Chinese patients with central nervous system myeloma invasion. Methods The diagnosis, therapy and prognosis were analyzed retrospectively in 11 Chinese multiple myeloma patients with central nervous system infiltration from a total of 625 patients who have been treated at Changzheng Hospital (Shanghai, China) between January 1993 and May 2009. Survival curve was constructed with the use of Kaplan-Meier estimates. Results There were 11 patients with central nervous system involvement from 625 multiple myeloma patients. The occurrence rate was 1.8%. Ten of the 11 patients had other extramedullary diseases. Symptoms included cerebral symptoms, cranial nerve palsies, and spinal cord or spinal nerve roots symptoms. Cerebrospinal fluid was abnormal in 7 patients, usually exhibiting pleocytosis and elevated protein content, plus positive cytologic findings. Specific magnetic resonance imaging findings suggestive of central nervous system invasion were found in 9 patients. After a median follow-up of 19 months, 3 patients were alive. The median overall survival for all patients was 23 months, while the median overall survival for patients after central nervous system invasion was merely 6 months. Conclusions It is exceedingly rare for there to be central nervous system infiltration in multiple myeloma patients. When it occurs, the prognosis is extremely poor despite the use of aggressive local and systemic treatment including stem cell transplantation.  相似文献
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