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81.
Taiji Yamazaki Kenji Hibi Tsunenobu Takase Ekmel Tezel Hiroshi Nakayama Yasushi Kasai Katsuki Ito Seiji Akiyama Tetsuro Nagasaka Akimasa Nakao 《Clinical cancer research》2002,8(1):192-195
PURPOSE AND EXPERIMENTAL DESIGN: We proved recently that PGP9.5-negative pancreatic cancer patients had significantly better survival rates compared with those who were PGP9.5 positive, and PGP9.5 may be a novel marker for indicating the prognosis of pancreatic cancer patients. In this study, we examined the expression of PGP9.5 in primary colorectal cancers using immunohistochemistry and correlated the result with the clinicopathological features. RESULTS: Of 74 colorectal cancer specimens examined, 33 cases (46%) showed positive staining with PGP9.5 in most tumor cells, whereas no PGP9.5 expression was detected in adjacent normal epithelium. Subsequently, we correlated PGP9.5 expression in tumors with the clinicopathological features of affected patients and found two significant differences in maximal tumor size and the extent of tumor (P = 0.035 and 0.019, respectively). CONCLUSION: This result suggests that PGP9.5 expression is related to tumor progression and may be useful as a marker for invasive colorectal cancer. 相似文献
82.
Nakashima I Fujihara K Kimpara T Okita N Takase S Itoyama Y 《Archives of neurology》2001,58(1):101-104
BACKGROUND: Magnetic resonance imaging (MRI) is useful for demonstrating demyelinating lesions in patients with multiple sclerosis (MS). Magnetic resonance imaging studies show that MS lesions are generally not uniform in shape, size, or distribution. Linearly shaped lesions at the trigeminal root entry zone have been occasionally reported in single cases of MS, but, to our knowlege, the frequency and the clinical features of such patients have not been comprehensively characterized. OBJECTIVE: To describe the frequency and the clinical and laboratory features of patients with MS who had linearly shaped lesions at the trigeminal root as seen on MRI. DESIGN AND SETTING: A retrospective review of medical records and MRI films of Japanese patients with MS admitted to a university hospital and its affiliated hospital in Sendai, Japan. PATIENTS AND METHODS: Brain MRI films of 74 consecutive Japanese patients with MS (51 females and 23 males) were studied retrospectively and the clinical and laboratory features of the patients with linearly shaped lesions at the trigeminal root were also investigated retrospectively. RESULTS: Five patients (6.8%) were shown to have T1-weighted-hypointense, T2-weighted-hyperintense, nonenhanced linear lesions in the pons on MRI, and these were uniformly localized in the intramedullary portion of the trigeminal root. All of these patients had clinically definite MS and had various types of facial sensory disturbances, such as neuralgia (1 patient), hypesthesia (2 patients), or paresthesia (3 patients). No other clinical or laboratory feature was characteristic in these 5 patients. CONCLUSIONS: Linear pontine trigeminal root lesions were common in our patients with MS. They were associated with various facial sensory symptoms. Since similar lesions are formed in animal models of herpes simplex virus infection, further study is needed to clarify whether these MS lesions are virally induced. 相似文献
83.
BACKGROUND: Kienb?ck disease is caused by aseptic necrosis of the lunate. In the advanced stages of the disease, carpal collapse, joint incongruity, and osteoarthritis develop. We performed lunate excision, capitate osteotomy, and intercarpal arthrodesis (the modified procedure of Graner et al.) on fifteen patients with stage-IIIB or IV Kienb?ck disease. This report is a review of the findings in these patients. METHODS: The subjects ranged in age from twenty-six to fifty-four years (mean, 39.2 years) at the time of surgery. We evaluated the results more than five years postoperatively (range, sixty-two to 145 months postoperatively; mean, 79.3 months postoperatively). Therapeutic results were evaluated according to the scoring system of Evans et al. RESULTS: Pain disappeared after surgery in most patients. Others had a reduction in the intensity of the pain to a mild level. The grip strength on the affected side had recovered to about 80% of that on the unaffected side twelve months after surgery. The long-term results were graded as good in eleven of the patients, as fair in two, and as poor in two. Postoperative radiographs showed that the carpal bone parameters (carpal height index and radioscaphoid angle) had improved. Radiographic osteoarthritic changes occurred in all of the patients; however, except for moderate limitation of the range of motion at the wrist joint, these findings did not affect the level of pain, grip strength, or activities of daily living. CONCLUSIONS: Lunate excision followed by capitate osteotomy and intercarpal arthrodesis (the modified procedure of Graner et al.) is a reliable form of treatment for advanced Kienb?ck disease, with favorable results for at least five years postoperatively. 相似文献
84.
Wight E Küng CF Moreau P Takase H Bersinger NA Lüscher TF 《Journal of the Society for Gynecologic Investigation》2000,7(2):106-113
OBJECTIVES: To investigate the effects of aging, ovarian ablation, and pregnancy on vascular reactivity of the rat uterine artery. METHODS: Segments of uterine artery from 3-month-old pregnant and nonpregnant Wistar rats and from aged and ovariectomized animals, both 9 months of age, were exposed in vitro to vasoactive mediators. Absolute contractile force as well as endothelium-dependent and -independent vascular reactivity were determined. Isometric tension was recorded using a modified Mulvany myograph system. Results were compared with analysis of variance and Bonferroni-Dunn post hoc analysis and correlated with serum estradiol levels. RESULTS: Aging up to 9 months decreased absolute tension of uterine arteries in vitro elicited by KCl (P < .0001), while not affecting receptor-operated responses to norepinephrine, endothelin-1, and angiotensin II. After ovarian ablation maximal contraction to norepinephrine was selectively reduced in the aged animal (P = .0053). Pregnancy increased absolute tension to KCl (P < .0001), norepinephrine (P < .008), and endothelin-1 (P = .0003), whereas relative contractile force (percentage of KCl) induced by norepinephrine and endothelin-1 remained unchanged and that induced by angiotension II decreased (P = .0001) in pregnant animals. In addition, pregnancy increased sensitivity to the endothelium-dependent vasodilator acetylcholine (P = .0022) but decreased that to the endothelium-independent vasodilator sodium nitroprusside (P = .0062). Endothelium-dependent relaxation correlated with serum estrogen levels remained unchanged in 9-month-old Wistar rats, which physiologically exhibited high serum estrogen concentrations but was impaired with regard to both maximum relaxation (P < .0001) and sensitivity in aged rats (P = .0007) after ovariectomy. CONCLUSIONS: Vascular contractility is impaired in the uterine artery of the aged rat as evidenced by reduced responses to KCl, whereas responses to receptor-operated agonists remain unchanged. Functional ovaries are essential to preserve endothelium-dependent relaxation in aging animals. During pregnancy, contractile machinery and endothelium-dependent relaxation are enhanced. In contrast, contractions to angiotensin II and endothelium-independent relaxation to sodium nitroprusside are reduced in late pregnancy. These changes in reactivity of the uterine artery may be important for the regulation of blood flow in the uterus according to physiologic needs. 相似文献
85.
Play fighting of homosexual and heterosexual dyads in golden hamsters was studied. The behaviors of male-male (MM), female-female (FF), and female-male (FM) dyads were recorded from the 25th to the 31st day of age. Play fighting activity of heterosexual dyads was depressed since MF and FM dyads exhibited a significantly high physical contact time and engaged in less play fighting, with a significantly lower time spent on such activity. Alternation ratio in the pinning posture was very high and subjects did not differ in the mean number of active (top) and passive pinning (under) in each dyad, showing an inexistence of sex dominance. In most cases, differences in the performances of MM and FF dyads were not significant. We have concluded that play fighting in golden hamsters may be predominantly modulated by environmental stimuli (sex of the partner) rather than by endogenous stimuli (androgen level). 相似文献
86.
Electrophysiological investigation of hemifacial spasm: F-waves of the facial muscles 总被引:1,自引:0,他引:1
Summary In patients with hemifacial spasm (HFS), the spasm is due to cross-compression of the facial nerve by a blood vessel. There are currently two hypotheses for the mechanism of HFS: 1) the spasm is caused by ephaptic transmission and an increase in excitability at the site of compression; and 2) the spasm is caused by hyperexcitability in the facial nerve nucleus. In peripheral nerves, F-waves, which result from the backfiring of antidromically activated anterior horn cells, have been proposed as indices of proximal motoneuron conduction and anterior horn cell excitability. Enhancement of the F-waves indicates increased anterior horn cell excitability. We have therefore measured F-waves in the facial muscle of HFS patients in order to investigate the exitability of the facial nerve nucleus.The authors obtained facial nerve evoked responses from 20 HFS patients before microvascular decompression (MVD), 10 HFS patients after MVD and 10 healthy controls. The F-waves, obtained with surface electrodes from the mentalis muscle, were the second response after the M-wave. On the patient's spasm side, the F-wave duration, F/M amplitude ratio and frequency of F-wave appearance significantly increased compared with those of the normal side or healthy controls; minimum latency and chronodispersion did not significantly differ between these groups. In patients whose spasm disappeared completely following MVD, the abnormal muslce response (lateral spread), which is a characteristic sign of HFS, and the enhancement of the F-wave eventually also disappeared. Because of the correlation between HFS and F-waves, the authors' study supports the hypothesis that the cause of HFS is hyperexcitability of the facial motonucleus. 相似文献
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