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81.
丝光绿蝇饲养初步研究 总被引:6,自引:1,他引:5
目的通过对丝光绿蝇的室内饲养,观察其驯化以及饲养的生物学。方法采用煮熟的鲢鱼引诱丝光绿蝇产卵,收集其卵块,置于室内采用人工配制饲料进行驯化饲养。结果丝光绿蝇第1代从卵发育至成蝇需14天,其中三龄期约5天,蛹期约6天。成蝇产卵前期约7天,卵散产。第2代从卵发育至成蝇约需13天,其中三龄期约4天,蛹期约6天。结论丝光绿蝇室内驯养在温度26℃~31℃,相对湿度75%条件下,从卵到蝇历期为13~14天,驯养初期,其生物学与自然条件下相比有所改变。 相似文献
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Since the introduction of anterior approaches to the cervical spine for the surgical treatment of degenerative disc disease, controversies have developed regarding the necessity of fusion following anterior cervical discectomy, the use of allografts instead of autologous bone for fusion, and, recently, the employment of anterior cervical plating systems in addition to fusion for uncomplicated disc disease. We reviewed seven clinical papers dealing with these issues; these articles surveyed a total of 1153 patients. Several observations can be made from these reviews. First, there is little or no difference in clinical outcome following single-level anterior discectomy, whether a fusion is performed or not, regardless of whether the operation was for soft discs or osteophytes. Second, most patients who underwent two-level discectomies had outcomes comparable to patients who underwent surgery at one level, regardless of whether they were fused or not. Data from four prospective randomized clinical studies in addition to multiple non-randomized or retrospective studies support these conclusions. Although the incidence of complications such as persistent postoperative posterior cervical and shoulder pain and kyphotic deformities is higher in unfused patients (and is quite significant in some series), the advantages conferred by interbody fusion such as biomechanical stability, decreased incidence of kyphotic deformity, and decreased pain are offset by graft and donor-site morbidity. Specific indications for fusion include multi-level discectomies, significant straightening of the cervical spine, failed prior fusions, and trauma. It has been demonstrated that comparable fusion rates can be achieved with allografts rather than harvested autologous bone. The advantages of autografts over allografts are relatively slight in most patients who undergo anterior fusion for one- or two-level disc disease, although patients with impaired healing, significant osteopenia, or concomitant microvascular disease, such as chronic smokers, may benefit from autologous bone. The use of allografts avoids donor-site morbidity in patients without these problems. Anterior cervical plates are useful for cases of instability requiring fusion (such as trauma); these implants may decrease reoperation rates and the incidence of delayed instability in select cases. However, the cost-effectiveness of their generalized use for uncomplicated cervical disc disease has not been demonstrated. In conclusion, a general statement regarding the optimal surgical treatment for cervical disc herniations using anterior approaches is difficult to make with this limited review. Surgeons' experience and familiarity with a particular approach are probably the most important factors in ensuring successful outcomes. 相似文献
84.
Alvarez L Peris P Bedini JL Parés A Monegal A Guañabens N Mas E Aibar C Ballesta AM 《Calcified tissue international》1999,64(4):301-303
Serum tartrate-resistant acid phosphatase (TRAcP) activity is considered to be a biochemical marker of bone resorption. Recently,
a lack of specificity of collagen-related markers for assessing bone turnover has been observed in patients with chronic liver
disease. Thus, it could be of great interest to determine serum TRAcP activity in such patients. However, nonspecificity of
the analytical reaction could occur when hemolyzed, lipemic, or icteric specimens are analyzed. Therefore, we have studied
the interference caused by bilirubin in the measurement of serum TRAcP activity using the Hillmann method. The interference
was assessed in two pools of serum containing different bilirubin concentrations but with similar total AcP levels. Mixing
proportional parts of the two pools, 10 samples were also obtained. Serum activities of total AcP and TRAcP, and the concentration
of bilirubin were measured in the 10 samples. Both the actual and the expected values obtained by theoretical calculations
were compared. Serum bilirubin values of 2.4 mg/dl showed a negative interference of 15% in the determination of serum TRAcP
activity, whereas values of bilirubin higher than 10 mg/dl interfered totally with the measurement of serum TRAcP. Bilirubin
did not interfere with the total AcP determination. This study clearly shows the interference of bilirubin in the determination
of serum TRAcP. This finding should be considered when bone metabolism disorders are evaluated in jaundiced patients.
Received: 6 April 1998 / Accepted: 1 October 1998 相似文献
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C L Strickland P C Weber W T Windsor Z Wu H V Le M M Albanese C S Alvarez D Cesarz J del Rosario J Deskus A K Mallams F G Njoroge J J Piwinski S Remiszewski R R Rossman A G Taveras B Vibulbhan R J Doll V M Girijavallabhan A K Ganguly 《Journal of medicinal chemistry》1999,42(12):2125-2135
Crystallographic and thermodynamic studies of farnesyl protein transferase (FPT) complexed with novel tricyclic inhibitors provide insights into the observed SAR for this unique class of nonpeptidic FPT inhibitors. The crystallographic structures reveal a binding pattern conserved across the mono-, di-, and trihalogen series. In the complexes, the tricycle spans the FPT active site cavity and interacts with both protein atoms and the isoprenoid portion of bound farnesyl diphosphate. An amide carbonyl, common to the tricyclic compounds described here, participates in a water-mediated hydrogen bond to the protein backbone. Ten high-resolution crystal structures of inhibitors complexed with FPT are reported. Included are crystallographic data for FPT complexed with SCH 66336, a compound currently undergoing clinical trials as an anticancer agent (SCH 66336, 4-[2-[4-(3,10-dibromo-8-chloro-6,11-dihydro-5H-benzo[5, 6]cyclohepta[1, 2-b]pyridin-11-yl)-1-piperidinyl]-2-oxoethyl]-1-piperidinecarbo xamide ). Thermodynamic binding parameters show favorable enthalpies of complex formation and small net entropic contributions as observed for 4-[2-[4-(3,10-dibromo-8-chloro-6,11-dihydro-11H-benzo[5, 6]cyclohepta[1, 2-b]pyridin-11-ylidene)-1-piperidinyl]-2-oxoethyl]pyridine N-oxide where DeltaH degrees bind = -12.5 kcal/mol and TDeltaS degrees bind = -1.5 kcal/mol. 相似文献
89.
A. Isla F. Alvarez M. Gutiérrez C. Gamallo M. García-Blázquez A. Vega 《Neuroradiology》1996,38(3):211-213
Primary lymphomas of the cranial vault are rare; only six patients have been described in the literature. We report a 75-year-old woman who was admitted to our hospital after a focal seizure. CT showed a homogeneous mass which, on contrast enhancement, was similar to a meningioma. The tumour was excised and found to be a centroblastic, centrocytic non-Hodgkin's lymphoma. Treatment was completed with radiotherapy and chemotherapy. 相似文献
90.
Voluntary rapid elbow flexion movements were studied in 14 patients with athetosis on the basis of cerebral palsy. When the movement was attempted with one arm, other muscles inappropriate for the task, such as muscles in the opposite limb, were also activated. EMG activity of the biceps and triceps was analysed in detail, and the patterns seen in the different patients were divided into six groups: (1) The normal "ballistic" triphasic pattern, with bursts of normal duration, alternating in biceps and triceps, but the triceps might be activated first, causing the limb to extend rather than flex, (2) The triphasic pattern, with bursts of long duration, (3) Repetitive cycles of the triphasic pattern with particularly long antagonist bursts, apparently limiting the movement in each cycle, (4) Long bursts synchronous in agonist and antagonist muscles, (5) Continuous activity of the agonist, with reduction in activity of the antagonist, (6) Failure to be able to do the task. The pathophysiology of athetosis is that voluntary movement is characterised by excessive muscular activity, most prominently in inappropriate muscles, both extraneous to the task and directly antagonistic. 相似文献